Local grand unification in the heterotic landscape

International Nuclear Information System (INIS)

Schmidt, Jonas

2009-06-01

We consider the possibility that the unification of the electroweak interactions and the strong force arises from string theory, at energies significantly lower than the string scale. As a tool, an effective grand unified field theory in six dimensions is derived from an anisotropic orbifold compactification of the heterotic string. It is explicitly shown that all anomalies cancel in the model, though anomalous Abelian gauge symmetries are present locally at the boundary singularities. In the supersymmetric vacuum additional interactions arise from higher-dimensional operators. We develop methods that relate the couplings of the effective theory to the location of the vacuum, and find that unbroken discrete symmetries play an important role for the phenomenology of orbifold models. An efficient algorithm for the calculation of the superpotential to arbitrary order is developed, based on symmetry arguments. We furthermore present a correspondence between bulk fields of the orbifold model in six dimensions, and the moduli fields that arise from compactifying four internal dimensions on a manifold with non-trivial gauge background. (orig.)

Local grand unification in the heterotic landscape

Energy Technology Data Exchange (ETDEWEB)

Schmidt, Jonas

2009-07-15

We consider the possibility that the unification of the electroweak interactions and the strong force arises from string theory, at energies significantly lower than the string scale. As a tool, an effective grand unified field theory in six dimensions is derived from an anisotropic orbifold compactification of the heterotic string. It is explicitly shown that all anomalies cancel in the model, though anomalous Abelian gauge symmetries are present locally at the boundary singularities. In the supersymmetric vacuum additional interactions arise from higher-dimensional operators. We develop methods that relate the couplings of the effective theory to the location of the vacuum, and find that unbroken discrete symmetries play an important role for the phenomenology of orbifold models. An efficient algorithm for the calculation of the superpotential to arbitrary order is developed, based on symmetry arguments. We furthermore present a correspondence between bulk fields of the orbifold model in six dimensions, and the moduli fields that arise from compactifying four internal dimensions on a manifold with non-trivial gauge background. (orig.)

Gauge hierarchy in an SO(10) supersymmetric grand unified model

International Nuclear Information System (INIS)

Zhiyong, Z.

1982-01-01

An SO(10) supersymmetric grand unified model is constructed in which the gauge hierarchy problem may be solved. Using Higgs superfields belonging to the SO(10) representations 16, 10 and 54, it is found that if SO(10) is broken down to SU(3)sub(c)xSU(2)sub(L)xU(1) via SO(6)xSO(4)approximately equal to SU(4)sub(c)xSU(2)sub(L)xSU(2)sub(R) at unification mass scales without supersymmetry breaking, the gauge hierarchy puzzle might be carried away. It is also shown that the colour-triplet Higgs, which mediates proton decay, is superheavy by an incredibly accurate, but 'natural' adjustment of parameters in the potential. (author)

Selected topics in grand unification

International Nuclear Information System (INIS)

Seckel, D.

1983-01-01

This dissertation is a collection of four pieces of research dealing with grand unification. The topics are neutron oscillation, CP violation, magnetic monopole abundance and distribution in neutron stars, and a proposal for an inflationary cosmology driven by stress-energy in domain walls

Revisiting top-bottom-tau Yukawa unification in supersymmetric grand unified theories

International Nuclear Information System (INIS)

Tobe, Kazuhiro; Wells, James D.

2003-01-01

Third family Yukawa unification, as suggested by minimal SO(10) unification, is revisited in light of recent experimental measurements and theoretical progress. We characterize unification in a semi-model-independent fashion, and conclude that finite b quark mass corrections from superpartners must be non-zero, but much smaller than naively would be expected. We show that a solution that does not require cancellations of dangerously large tanβ effects in observables implies that scalar superpartner masses should be substantially heavier than the Z scale, and perhaps inaccessible to all currently approved colliders. On the other hand, gauginos must be significantly lighter than the scalars. We demonstrate that a spectrum of anomaly-mediated gaugino masses and heavy scalars works well as a theory compatible with third family Yukawa unification and dark matter observations

Classification of three-family grand unification in string theory. II. The SU(5) and SU(6) models

International Nuclear Information System (INIS)

Kakushadze, Z.; Tye, S.H.

1997-01-01

Requiring that supersymmetric SU(5) and SU(6) grand unifications in the heterotic string theory must have three chiral families, adjoint (or higher representation) Higgs fields in the grand unified gauge group, and a non-Abelian hidden sector, we construct such string models within the framework of free conformal field theory and asymmetric orbifolds. Within this framework, we construct all such string models via Z 6 asymmetric orbifolds that include a Z 3 outerautomorphism, the latter yielding a level-three current algebra for the grand unification gauge group SU(5) or SU(6). We then classify all such Z 6 asymmetric orbifolds that result in models with a non-Abelian hidden sector. All models classified in this paper have only one adjoint (but no other higher representation) Higgs field in the grand unified gauge group. This Higgs field is neutral under all other gauge symmetries. The list of hidden sectors for three-family SU(6) string models are SU(2), SU(3), and SU(2)circle-times SU(2). In addition to these, three-family SU(5) string models can also have an SU(4) hidden sector. Some of the models have an apparent anomalous U(1) gauge symmetry. copyright 1997 The American Physical Society

New aspects of flavour model building in supersymmetric grand unification

Energy Technology Data Exchange (ETDEWEB)

Spinrath, Martin

2010-05-19

We derive predictions for Yukawa coupling ratios within Grand Unified Theories generated from operators with mass dimension four and five. These relations are a characteristic property of unified flavour models and can reduce the large number of free parameters related to the flavour sector of the Standard Model. The Yukawa couplings of the down-type quarks and charged leptons are affected within supersymmetric models by tan {beta}-enhanced threshold corrections which can be sizeable if tan {beta} is large. In this case their careful inclusion in the renormalisation group evolution is mandatory. We analyse these corrections and give simple analytic expressions and numerical estimates for them. The threshold corrections sensitively depend on the soft supersymmetry breaking parameters. Especially, they determine the overall sign of the corrections and therefore if the affected Yukawa couplings are enhanced or suppressed. In the minimal supersymmetric extension of the Standard Model many free parameters are introduced by supersymmetry breaking about which we make some plausible assumptions in our first simplified approach. In a second, more sophisticated approach we use three common breaking schemes in which all the soft breaking parameters at the electroweak scale can be calculated from only a handful of parameters. Within the second approach, we apply various phenomenological constraints on the supersymmetric parameters and find in this way new viable Yukawa coupling relations, for example y{sub {mu}}/y{sub s}=9/2 or 6 or y{sub {tau}}/y{sub b}=3/2 in SU(5). Furthermore, we study a special class of quark mass matrix textures for small tan {beta} where {theta}{sup u}{sub 13}={theta}{sup d}{sub 13}=0. We derive sum rules for the quark mixing parameters and find a simple relation between the two phases {delta}{sup u}{sub 12} and {delta}{sup d}{sub 12} and the right unitarity triangle angle {alpha} which suggests a simple phase structure for the quark mass matrices where

Leptoquark mechanism of neutrino masses within the grand unification framework

Science.gov (United States)

Doršner, Ilja; Fajfer, Svjetlana; Košnik, Nejc

2017-06-01

We demonstrate the viability of the one-loop neutrino mass mechanism within the framework of grand unification when the loop particles comprise scalar leptoquarks (LQs) and quarks of the matching electric charge. This mechanism can be implemented in both supersymmetric and non-supersymmetric models and requires the presence of at least one LQ pair. The appropriate pairs for the neutrino mass generation via the up-type and down-type quark loops are S_3-R_2 and S_{1, 3}-\\tilde{R}_2, respectively. We consider two distinct regimes for the LQ masses in our analysis. The first regime calls for very heavy LQs in the loop. It can be naturally realized with the S_{1, 3}-\\tilde{R}_2 scenarios when the LQ masses are roughly between 10^{12} and 5 × 10^{13} GeV. These lower and upper bounds originate from experimental limits on partial proton decay lifetimes and perturbativity constraints, respectively. Second regime corresponds to the collider accessible LQs in the neutrino mass loop. That option is viable for the S_3-\\tilde{R}_2 scenario in the models of unification that we discuss. If one furthermore assumes the presence of the type II see-saw mechanism there is an additional contribution from the S_3-R_2 scenario that needs to be taken into account beside the type II see-saw contribution itself. We provide a complete list of renormalizable operators that yield necessary mixing of all aforementioned LQ pairs using the language of SU(5). We furthermore discuss several possible embeddings of this mechanism in SU(5) and SO(10) gauge groups.

Leptoquark mechanism of neutrino masses within the grand unification framework

Energy Technology Data Exchange (ETDEWEB)

Dorsner, Ilja [University of Split, Faculty of Electrical Engineering, Mechanical Engineering and Naval Architecture in Split (FESB), Split (Croatia); Fajfer, Svjetlana; Kosnik, Nejc [University of Ljubljana, Department of Physics, Ljubljana (Slovenia); Jozef Stefan Institute, Jamova 39, P. O. Box 3000, Ljubljana (Slovenia)

2017-06-15

We demonstrate the viability of the one-loop neutrino mass mechanism within the framework of grand unification when the loop particles comprise scalar leptoquarks (LQs) and quarks of the matching electric charge. This mechanism can be implemented in both supersymmetric and non-supersymmetric models and requires the presence of at least one LQ pair. The appropriate pairs for the neutrino mass generation via the up-type and down-type quark loops are S{sub 3}-R{sub 2} and S{sub 1,3}-R{sub 2}, respectively. We consider two distinct regimes for the LQ masses in our analysis. The first regime calls for very heavy LQs in the loop. It can be naturally realized with the S{sub 1,3}-R{sub 2} scenarios when the LQ masses are roughly between 10{sup 12} and 5 x 10{sup 13} GeV. These lower and upper bounds originate from experimental limits on partial proton decay lifetimes and perturbativity constraints, respectively. Second regime corresponds to the collider accessible LQs in the neutrino mass loop. That option is viable for the S{sub 3}-R{sub 2} scenario in the models of unification that we discuss. If one furthermore assumes the presence of the type II see-saw mechanism there is an additional contribution from the S{sub 3}-R{sub 2} scenario that needs to be taken into account beside the type II see-saw contribution itself. We provide a complete list of renormalizable operators that yield necessary mixing of all aforementioned LQ pairs using the language of SU(5). We furthermore discuss several possible embeddings of this mechanism in SU(5) and SO(10) gauge groups. (orig.)

A review of supersymmetric GUT and its implication to proton decay

International Nuclear Information System (INIS)

Sakai, N.

1983-01-01

Supersymmetric grand unification and its implication to proton decay are reviewed. The author discusses prototype models and reviews recent studies of model building, in particular models with an intermediate scale (10/sup 10/ -- 10/sup 12/ Gev) supersymmetry breaking. Finally proton decay in supersymmetric models is reviewed

Introduction to grand unification theories

International Nuclear Information System (INIS)

Kang, Kyungsik

1980-01-01

We introduce the Georgi-Glashow model based on the minimal gauge group SU(5) as a prototype grand unification theory of the electroweak and strong interactions. Simple estimation of sin 2 thetasub(W) in the symmetry limit and the renormalization corrections at the energy scale of Msub(W) are given along wich other successes of the SU(5) model

Third-generation effects on fermion mass predictions in supersymmetric grand unified theories

International Nuclear Information System (INIS)

Naculich, S.G.

1993-01-01

Relations among fermion masses and mixing angles at the scale of grand unification are modified at lower energies by renormalization group running induced by gauge and Yukawa couplings. In supersymmetric theories, the b quark and τ lepton Yukawa couplings, as well as the t quark coupling, may cause significant running if tanβ, the ratio of Higgs field expectation values, is large. We present approximate analytic expressions for the scaling factors for fermion masses and CKM matrix elements induced by all three third generation Yukawa couplings. We then determine how running caused by the third generation of fermions affects the predictions arising from three possible forms for the Yukawa coupling matrices at the GUT scale: the Georgi-Jarlskog, Giudice, and Fritzsch textures

A non Supersymmetric SO(10) Grand Unified Model for All the Physics below $M_{GUT}$

CERN Document Server

Altarelli, Guido

2013-01-01

We present a renormalizable non supersymmetric Grand Unified SO(10) model which, at the price of a large fine tuning, is compatible with all compelling phenomenological requirements below the unification scale and thus realizes a minimal extension of the SM, unified in SO(10) and describing all known physics below $M_{GUT}$. These requirements include coupling unification at a large enough scale to be compatible with the bounds on proton decay; a Yukawa sector in agreement with all the data on quark and lepton masses and mixings and with leptogenesis as the origin of the baryon asymmetry of the Universe; an axion arising from the Higgs sector of the model, suitable to solve the strong CP problem and to account for the observed amount of Dark Matter. The above constraints imposed by the data are very stringent and single out a particular breaking chain with the Pati-Salam group at an intermediate scale $M_I\\sim10^{11}$ GeV.

Dark Matter after LHC Run I: Clues to Unification

Directory of Open Access Journals (Sweden)

Olive Keith A.

2017-01-01

Full Text Available After the results of Run I, can we still ‘guarantee’ the discovery of supersymmetry at the LHC? It is shown that viable dark matter models in CMSSM-like models tend to lie in strips (co-annihilation, funnel, focus point. The role of grand unification in constructing supersymmetric models is discussed and it is argued that non-supersymmetric GUTs such as SO(10 may provide solutions to many of the standard problems addressed by supersymmetry.

Dynkin weights and global supersymmetry in grand unification

International Nuclear Information System (INIS)

Frampton, P.H.; Kephart, T.W.

1982-01-01

The requirement that supersymmetry be unbroken in a supersymmetrized gauge theory is shown to imply vanishing Dynkin weight of the components of the Higgs field representation receiving vacuum expectation values. As a corollary a compact expression is obtained for the Dynkin weights of general SU(N) representations. Examples are given for supersymmetrized grand unified theories

Gauge coupling unification from unified theories in higher dimensions

International Nuclear Information System (INIS)

Hall, Lawrence J.; Nomura, Yasunori

2002-01-01

Higher dimensional grand unified theories, with gauge symmetry breaking by orbifold compactification, possess SU(5) breaking at fixed points, and do not automatically lead to tree-level gauge coupling unification. A new framework is introduced that guarantees precise unification--even the leading loop threshold corrections are predicted, although they are model dependent. Precise agreement with the experimental result, α s exp =0.117±0.002, occurs only for a unique theory, and gives α s KK =0.118±0.004±0.003. Remarkably, this unique theory is also the simplest, with SU(5) gauge interactions and two Higgs hypermultiplets propagating in a single extra dimension. This result is more successful and precise than that obtained from conventional supersymmetric grand unification, α s SGUT =0.130±0.004±Δ SGUT . There is a simultaneous solution to the three outstanding problems of 4D supersymmetric grand unified theories: a large mass splitting between Higgs doublets and their color triplet partners is forced, proton decay via dimension five operators is automatically forbidden, and the absence of fermion mass relations amongst light quarks and leptons is guaranteed, while preserving the successful m b /m τ relation. The theory necessarily has a strongly coupled top quark located on a fixed point and part of the lightest generation propagating in the bulk. The string and compactification scales are determined to be around 10 17 GeV and 10 15 GeV, respectively

Neutrino masses and b - τ unification in the supersymmetric standard model

International Nuclear Information System (INIS)

Vissani, F.; Smirnov, A.Yu.

1994-05-01

There are several indications that the Majorana masses of the right-handed neutrino components, M R , are at the intermediate scale: M R ∼ (10 10 - 10 12 ) GeV or even lighter. The renormalization effects due to large Yukawa couplings of neutrinos from region of momenta M R G are studied in the supersymmetric standard model. It is shown that neutrino renormalization effect can increase the m b /m τ ratio up to (10/15)%. This strongly disfavors m b - m τ unification for low values of tan β s . Lower bound on M R and tan β from the b - τ unification condition were found. The implications of the results to the see-saw mechanism of the neutrino mass generation are discussed. (author). 17 refs, 4 figs

Unification and supersymmetry

International Nuclear Information System (INIS)

Mohapatra, R.N.

1991-01-01

This book deals with some of the latest developments in our attempts to construct a unified theory of the fundamental interactions of nature. Among the topics covered are spontaneous symmetry breaking, grand unified theories, supersymmetry, and supergravity. The book starts with a quick review of elementary particle theory and continues with a discussion of composite quarks, leptons, Higgs bosons, and CP violation; it concludes with consideration of supersymmetric unification schemes, in which bosons and leptons are considered in some sense equivalent. The second edition is updated and corrected and contains new chapters on recent developments

Squark and slepton masses as probes of supersymmetric SO(10) unification

Energy Technology Data Exchange (ETDEWEB)

Balasubramanian Ananthanarayan; P. N. Pandita

2003-09-01

We carry out a detailed analysis of the non-universal supersymmetry breaking scalar masses arising in SO(10) supersymmetric unification. By considering patterns of squark and slepton masses, we show that a set of sum rules for the sfermion masses is independent of the manner in which SO(10) breaks. We discuss the reasons for this remarkable result. The phenomenology arising from such non-universality is shown to be practically unaffected by the symmetry breaking pattern.

Electric dipole moments as a test of supersymmetric unification

CERN Document Server

Dimopoulos, Savas K; Dimopoulos, S; Hall, L J

1995-01-01

In a class of supersymmetric grand unified theories, including those based on the gauge group SO(10), there are new contributions to the electric dipole moments of the neutron and electron, which arise as a heavy top quark effect. These contributions arise from CKM-like phases, not from phases of the supersymmetry breaking operators, and can be reliably computed in terms of the parameters of the weak scale supersymmetric theory. For the expected ranges of these parameters, the electric dipole moments of the neutron and the electron are predicted to be close to present experimental limits.

Supersymmetric grand unified theories from quarks to strings via SUSY GUTs

CERN Document Server

Raby, Stuart

2017-01-01

These course-tested lectures provide a technical introduction to Supersymmetric Grand Unified Theories (SUSY GUTs), as well as a personal view on the topic by one of the pioneers in the field. While the Standard Model of Particle Physics is incredibly successful in describing the known universe it is, nevertheless, an incomplete theory with many free parameters and open issues. An elegant solution to all of these quandaries is the proposed theory of SUSY GUTs. In a GUT, quarks and leptons are related in a simple way by the unifying symmetry and their electric charges are quantized, further the relative strength of the strong, weak and electromagnetic forces are predicted. SUSY GUTs additionally provide a framework for understanding particle masses and offer candidates for dark matter. Finally, with the extension of SUSY GUTs to string theory, a quantum-mechanically consistent unification of the four known forces (including gravity) is obtained. The book is organized in three sections: the first section contai...

Gravity-assisted exact unification in minimal supersymmetric SU(5) and its gaugino mass spectrum

International Nuclear Information System (INIS)

Tobe, Kazuhiro; Wells, James D.

2004-01-01

Minimal supersymmetric SU(5) with exact unification is naively inconsistent with proton decay constraints. However, it can be made viable by a gravity-induced non-renormalizable operator connecting the adjoint Higgs boson and adjoint vector boson representations. We compute the allowed coupling space for this theory and find natural compatibility with proton decay constraints even for relatively light superpartner masses. The modifications away from the naive SU(5) theory have an impact on the gaugino mass spectrum, which we calculate. A combination of precision linear collider and large hadron collider measurements of superpartner masses would enable interesting tests of the high-scale form of minimal supersymmetric SU(5)

Electroweak symmetry breaking in supersymmetric gauge-Higgs unification models

International Nuclear Information System (INIS)

Choi, Kiwoon; Jeong, Kwang-Sik; Okumura, Ken-ichi; Haba, Naoyuki; Shimizu, Yasuhiro; Yamaguchi, Masahiro

2004-01-01

We examine the Higgs mass parameters and electroweak symmetry breaking in supersymmetric orbifold field theories in which the 4-dimensional Higgs fields originate from higher-dimensional gauge supermultiplets. It is noted that such gauge-Higgs unification leads to a specific boundary condition on the Higgs mass parameters at the compactification scale, which is independent of the details of supersymmetry breaking mechanism. With this boundary condition, phenomenologically viable parameter space of the model is severely constrained by the condition of electroweak symmetry breaking for supersymmetry breaking scenarios which can be realized naturally in orbifold field theories. For instance, if it is assumed that the 4-dimensional effective theory is the minimal supersymmetric standard model with supersymmetry breaking parameters induced by the Scherk-Schwarz mechanism, a correct electroweak symmetry breaking can not be achieved for reasonable range of parameters of the model, even when one includes additional contributions to the Higgs mass parameters from the auxiliary component of 4-dimensional conformal compensator. However if there exists a supersymmetry breaking mediated by brane superfields, sizable portion of the parameter space can give a correct electroweak symmetry breaking. (author)

Gauge coupling unification in heterotic string models with gauge mediated supersymmetry breaking

International Nuclear Information System (INIS)

Anandakrishnan, Archana; Raby, Stuart

2011-01-01

We calculate the weak scale minimal supersymmetric standard model spectrum starting from a heterotic string theory compactified on an anisotropic orbifold. Supersymmetry breaking is mediated by vectorlike exotics that arise naturally in heterotic string theories. The messengers that mediate supersymmetry breaking come in incomplete grand unified theory (GUT) multiplets and give rise to nonuniversal gaugino masses at the GUT scale. Models with nonuniversal gaugino masses at the GUT scale have the attractive feature of allowing for precision gauge coupling unification at the GUT scale with negligible contributions from threshold corrections near the unification scale. The unique features of this minimally supersymmetric standard model spectrum are light gluinos and also large mass differences between the lightest and the next-to-lightest neutralinos and charginos which could lead to interesting signatures at the colliders.

Interplay between grand unification and supersymmetry in SU(5 ...

Indian Academy of Sciences (India)

energy MSSM. break the rank, Aulakh and his collaborators [10–12] have showed that R-parity is exact all the way down to low energies. In this case, grand unification tells us something about supersymmetry and even dark matter. In this article ...

From Minimal to Realistic Supersymmetric SU(5) Grand Unification

CERN Document Server

Altarelli, Guido; Masina, I; Altarelli, Guido; Feruglio, Ferruccio; Masina, Isabella

2000-01-01

We construct and discuss a "realistic" example of SUSY SU(5) GUT model, with an additional U(1) flavour symmetry, that is not plagued by the need of large fine tunings, like those associated with doublet-triplet splitting in the minimal model, and that leads to an acceptable phenomenology. This includes coupling unification with a value of alpha_s(m_Z) in much better agreement with the data than in the minimal version, an acceptable hierarchical pattern for fermion masses and mixing angles, also including neutrino masses and mixings, and a proton decay rate compatible with present limits (but the discovery of proton decay should be within reach of the next generation of experiments). In the neutrino sector the preferred solution is one with nearly maximal mixing both for atmospheric and solar neutrinos.

Particle physics models of inflation in supergravity and grand unification

International Nuclear Information System (INIS)

Kostka, Philipp Manuel

2010-01-01

magnetic monopoles at the end of the stage of inflation can be avoided. Finally, we sketch how in tribrid inflation models the concepts discussed in the two parts can be combined to realize inflation via Heisenberg symmetry in local supersymmetric SO(10) grand unification. (orig.)

Particle physics models of inflation in supergravity and grand unification

Energy Technology Data Exchange (ETDEWEB)

Kostka, Philipp Manuel

2010-12-03

production of stable magnetic monopoles at the end of the stage of inflation can be avoided. Finally, we sketch how in tribrid inflation models the concepts discussed in the two parts can be combined to realize inflation via Heisenberg symmetry in local supersymmetric SO(10) grand unification. (orig.)

Aspects of extra dimensional supersymmetric unified theories

International Nuclear Information System (INIS)

Fichet, S.

2011-09-01

The purpose of this work is to investigate Grand Unified Theories (GUTs) and to make the link with passed and upcoming experiments. The structure of this thesis is as follows. In the first chapter, we will briefly review the sequence of arguments leading to the Higgs mechanism, then to the different concepts underlying physics beyond the Standard Model, and to the paradigm of extra dimensional supersymmetric grand unified theories. At each level of the argumentation, we will mention the different solutions available. The second chapter introduces more formally supersymmetry and extra dimensions, focusing in particular on the aspects of symmetry breaking. Then, in the third chapter, we present in details the two frameworks of extra dimensional theories in which we worked, called supersymmetric gauge-Higgs unification (GHU) and holographic grand unification (HGU) as well as the developments and modifications we brought to them. The fourth chapter is devoted to the low energy viability of the GHU framework, as well as its phenomenological implications. The fifth chapter presents a more generic study of the property of GUT-scale degenerate Higgs mass matrix, common to both frameworks. Finally, the sixth chapter is devoted to the viability and phenomenological implications of the HGU framework, with special emphasis on lepton flavour violation. This quantitative study takes properly into account effects of matrix anarchy, as well as exact flavour observables. The results obtained should generalize, at least qualitatively, to any other model with similar localization and supersymmetry breaking features

SU(5) unification revisited

International Nuclear Information System (INIS)

Giveon, A.; Sarid, U.; Hall, L.J.; California Univ., Berkeley, CA

1991-01-01

Model-independent criteria for unification in the SU(5) framework are studied. These are applied to the minimal supersymmetric standard model and to the standard model with a split 45 Higgs representation. Although the former is consistent with SU(5) unification, the superpartner masses can vary over a wide range, and may even all lie well beyond the reach of planned colliders. Adding a split 45 to the standard model can also satisfy the unification criteria, so supersymmetric SU(5) is far from unique. Furthermore, we learn that separate Higgs doublets must couple to the top and bottom quarks in order to give a correct m b /m τ prediction. (orig.)

Low energy implications of minimal superstring unification

International Nuclear Information System (INIS)

Khalil, S.; Vissani, F.; Masiero, A.

1995-11-01

We study the phenomenological implications of effective supergravities based on string vacua with spontaneously broken N =1 supersymmetry by dilation and moduli F-terms. We further require Minimal String Unification, namely that large string threshold corrections ensure the correct unification of the gauge couplings at the grand unification scale. The whole supersymmetric mass spectrum turns out to be determined in terms of only two independent parameters, the dilaton-moduli mixing angle and the gravitino mass. In particular we discuss the region of the parameter space where at least one superpartner is ''visible'' at LEPII. We find that the most likely candidates are the scalar partner of the right-handed electron and the lightest chargino, with interesting correlations between their masses and with the mass of the lightest higgs. We show how discovering SUSY particles at LEPII might rather sharply discriminate between scenarios with pure dilaton SUSY breaking and mixed dilaton-moduli breaking. (author). 10 refs, 7 figs

Supersymmetric models and their phenomenology

International Nuclear Information System (INIS)

Ross, G.G.

1995-01-01

The prospects for unification of the Standard Model are considered and the need for supersymmetry discussed. The prediction of the gauge couplings, the electroweak breaking scale, the fermion masses and the dark matter abundance are all consistent with simple unification if there is a stage of supersymmetric unification below the TeV scale. The prospects for discovery of the new SUSY states is considered, both in the minimal supersymmetric standard model and in non-minimal extensions. (author)

Grand unification: status report

International Nuclear Information System (INIS)

Georgi, H.

1983-01-01

Grand unification is reviewed with regard to the flavor puzzle and the hierarchy puzzle. Progress in CP and the PQWWKDFS axion is reviewed. The neutrino mass and B-L research, the understanding and assimilation of the language of effective theories (which divide the momentum scale up into regions), with focus on the models, are surveyed. Various unified models are organized according to whether they address the hierarchy puzzle or the flavor puzzle. SU(5), SO(10), E6, and Higgs are considered simple and explicit models. Global symmetry addresses hierarchy puzzle, but the rules are unclear. In SO (18), with regard to hierarchy, perturbation theory breaks down. SO (14) fails for hierarchy because of GIM, b and t problems. Supersymmetry and technicolor with regard to flavor puzzle are questioned. The CP solution of ETC and Composite C models (addressing both flavor and hierarchy) is a minus. Composite A model has no evident virtues, and the basic idea of ETC model needs checking

Grand unification and supergravity

International Nuclear Information System (INIS)

Nanopoulos, D.V.

Grand Unified Theories (GUTs) are very successful, but they suffer from fine-tuning or hierarchy problems. It seems that more symmetry beyond the gauge symmetry is needed and indeed supersymmetric GUTs may provide the correct framework in solving the hierarchy problems. These are reviewed. From the results discussed, it is seen that for the first time in particle physics, gravity seems to play a dominant role. It may be responsible for GUT breaking, SU(2) x U(1) breaking, fermion masses, proton decay and a consistent cosmological picture. Supergravity seems to offer a consistent, effective theory for energies below the Planck scale to N=1 local SUSY but also, in the context of N=8 extended supergravity with a dynamically realized SU(8), there may be a consistent fundamental unified theory of all interactions. (U.K.)

Infrared fixed point solution for the top quark mass and unification of couplings in the MSSM

International Nuclear Information System (INIS)

Bardeen, W.A.; Carena, M.; Pokorski, S.; Wagner, C.E.M.

1993-08-01

We analyze the implications of the infrared quasi fixed point solution for the top quark mass in the Minimal Supersymmetric Standard Model. This solution could explain in a natural way the relatively large value of the top quark mass and, if confirmed experimentally, may be suggestive of the onset of nonperturbative physics at very high energy scales. In the framework of grand unification, the expected bottom quark -- tau lepton Yukawa coupling unification is very sensitive to the fixed point structure of the top quark mass. For the presently allowed values of the electroweak parameters and the bottom quark mass, the Yukawa coupling unification implies that the top quark mass must be within ten percent of its fixed point values

Reconciling grand unification with strings by anisotropic compactifications

International Nuclear Information System (INIS)

Dundee, Ben; Raby, Stuart; Wingerter, Akin

2008-01-01

We analyze gauge coupling unification in the context of heterotic strings on anisotropic orbifolds. This construction is very much analogous to effective five-dimensional orbifold grand unified theory field theories. Our analysis assumes three fundamental scales: the string scale M S , a compactification scale M C , and a mass scale for some of the vectorlike exotics M EX ; the other exotics are assumed to get mass at M S . In the particular models analyzed, we show that gauge coupling unification is not possible with M EX =M C , and in fact we require M EX C ∼3x10 16 GeV. We find that about 10% of the parameter space has a proton lifetime (from dimension six gauge exchange) 10 33 yr 0 e + ) 36 yr. The other 80% of the parameter space gives proton lifetimes below Super-Kamiokande bounds. The next generation of proton decay experiments should be sensitive to the remaining parameter space.

Grand unification and subcritical hybrid inflation

International Nuclear Information System (INIS)

Buchmueller, Wilfried; Ishiwata, Koji

2014-12-01

We consider hybrid inflation for small couplings of the inflaton to matter such that the critical value of the inflaton field exceeds the Planck mass. It has recently been shown that inflation then continues at subcritical inflaton field values where quantum fluctuations generate an effective inflaton mass. The effective inflaton potential interpolates between a quadratic potential at small field values and a plateau at large field values. An analysis of the allowed parameter space leads to predictions for the scalar spectral index n s and the tensor-to-scalar ratio r similar to those of natural inflation. Using the range for n s and r favoured by the Planck data, we find that the energy scale of the plateau is constrained to the interval (1.6-2.4) x 10 16 GeV which includes the energy scale of gauge coupling unification in the supersymmetric standard model. The tensor-to-scalar ratio is predicted to have the lower bound r>0.049 for 60 e-folds before the end of inflation.

Study of theory and phenomenology of some classes of family symmetry and unification models

International Nuclear Information System (INIS)

Kane, Gordon L.; King, Steve F.; Peddie, Iain N.R.; Velasco-Sevilla, Liliana

2005-01-01

We review and compare theoretically and phenomenologically a number of possible family symmetries, which when combined with unification, could be important in explaining quark, lepton and neutrino masses and mixings, providing new results in several cases. Theoretical possibilities include abelian or non-abelian, symmetric or non symmetric Yukawa matrices, Grand Unification or not. Our main focus is on anomaly-free U(1) family symmetry combined with SU(5) unification, although we also discuss other possibilities. We provide a detailed phenomenological fit of the fermion masses and mixings for several examples, and discuss the supersymmetric flavour issues in such theories, including a detailed analysis of lepton flavour violation. We show that it is not possible to quantitatively and decisively discriminate between these different theoretical possibilities at the present time

Confronting the conventional ideas of grand unification with fermion masses, neutrino oscillations and proton decay

Energy Technology Data Exchange (ETDEWEB)

Pati, J C [Department of Physics, University of Maryland, College Park (United States) and Stanford Linear Accelerator Center, Menlo Park (United States)

2002-09-15

It is noted that one is now in possession of a set of facts, which may be viewed as the matching pieces of a puzzle; in that all of them can be resolved by just one idea - that is grand unification. These include: (i) the observed family-structure, (ii) quantization of electric charge, (iii) meeting of the three gauge couplings, (iv) neutrino oscillations; in particular the mass squared-difference {delta}m{sup 2}({nu}{sub {mu}} - {nu}{sub {tau}}) (suggested by SuperK), (v) the intricate pattern of the masses and mixings of the fermions, including the smallness of V{sub cb} and the largeness of {theta}{sub {nu}{sub {mu}{nu}}{sub {tau}}}{sup osc}, and (vi) the need for B-L as a generator to implement baryogenesis (via leptogenesis). All these pieces fit beautifully together within a single puzzle board framed by supersymmetric unification, based on SO(10) or a string-unified G(224)-symmetry. The two notable pieces of the puzzle still missing, however, are proton decay and supersymmetry. A concrete proposal is presented, within a predictive SO(10)/G(224)- framework, that successfully describes the masses and mixings of all fermions, including the neutrinos - with eight predictions, all in agreement with observation. Within this framework, a systematic study of proton decay is carried out, which (a) pays special attention to its dependence on the fermion masses, including the superheavy Majorana masses of the right-handed neutrinos, and (b) limits the threshold corrections so as to preserve natural coupling unification. The study updates prior work by Babu, Pati and Wilczek, in the context of both MSSM and its (interesting) variant, the so-called ESSM, by allowing for improved values of the matrix elements and of the short and long-distance renormalization effects. It shows that a conservative upper limit on the proton lifetime is about (1/3 - 2) x 10{sup 34} years, with {nu}-barK{sup +} being the dominant decay mode, and quite possibly {mu}{sup p}+K{sup 0} and e

Confronting the conventional ideas of grand unification with fermion masses, neutrino oscillations and proton decay

International Nuclear Information System (INIS)

Pati, J.C.

2002-01-01

It is noted that one is now in possession of a set of facts, which may be viewed as the matching pieces of a puzzle; in that all of them can be resolved by just one idea - that is grand unification. These include: (i) the observed family-structure, (ii) quantization of electric charge, (iii) meeting of the three gauge couplings, (iv) neutrino oscillations; in particular the mass squared-difference Δm 2 (ν μ - ν τ ) (suggested by SuperK), (v) the intricate pattern of the masses and mixings of the fermions, including the smallness of V cb and the largeness of θ ν μ ν τ osc , and (vi) the need for B-L as a generator to implement baryogenesis (via leptogenesis). All these pieces fit beautifully together within a single puzzle board framed by supersymmetric unification, based on SO(10) or a string-unified G(224)-symmetry. The two notable pieces of the puzzle still missing, however, are proton decay and supersymmetry. A concrete proposal is presented, within a predictive SO(10)/G(224)- framework, that successfully describes the masses and mixings of all fermions, including the neutrinos - with eight predictions, all in agreement with observation. Within this framework, a systematic study of proton decay is carried out, which (a) pays special attention to its dependence on the fermion masses, including the superheavy Majorana masses of the right-handed neutrinos, and (b) limits the threshold corrections so as to preserve natural coupling unification. The study updates prior work by Babu, Pati and Wilczek, in the context of both MSSM and its (interesting) variant, the so-called ESSM, by allowing for improved values of the matrix elements and of the short and long-distance renormalization effects. It shows that a conservative upper limit on the proton lifetime is about (1/3 - 2) x 10 34 years, with ν-barK + being the dominant decay mode, and quite possibly μ p +K 0 and e + π 0 being prominent. This in turn strongly suggests that an improvement in the current

Searching for beyond the minimal supersymmetric standard model at the laboratory and in the sky

Energy Technology Data Exchange (ETDEWEB)

Kim, Ju Min

2010-09-15

We study the collider signals as well as Dark Matter candidates in supersymmetric models. We show that the collider signatures from a supersymmetric Grand Unification model based on the SO(10) gauge group can be distinguishable from those from the (constrained) minimal supersymmetric Standard Model, even though they share some common features. The N=2 supersymmetry has the characteristically distinct phenomenology, due to the Dirac nature of gauginos, as well as the extra adjoint scalars. We compute the cold Dark Matter relic density including a class of one-loop corrections. Finally, we discuss the detectability of neutralino Dark Matter candidate of the SO(10) model by the direct and indirect Dark Matter search experiments. (orig.)

Searching for beyond the minimal supersymmetric standard model at the laboratory and in the sky

International Nuclear Information System (INIS)

Kim, Ju Min

2010-09-01

We study the collider signals as well as Dark Matter candidates in supersymmetric models. We show that the collider signatures from a supersymmetric Grand Unification model based on the SO(10) gauge group can be distinguishable from those from the (constrained) minimal supersymmetric Standard Model, even though they share some common features. The N=2 supersymmetry has the characteristically distinct phenomenology, due to the Dirac nature of gauginos, as well as the extra adjoint scalars. We compute the cold Dark Matter relic density including a class of one-loop corrections. Finally, we discuss the detectability of neutralino Dark Matter candidate of the SO(10) model by the direct and indirect Dark Matter search experiments. (orig.)

Bounds on the number of possible Higgs particles using grand unification and exceptional Lie groups

International Nuclear Information System (INIS)

El Naschie, M.S.

2008-01-01

The total sum of dimensions of a magnum exceptional Lie symmetry groups hierarchy is 4α-bar o =(4)(137+k o )≅548. Dividing this value among the various quantum fields leads to the possibility of an eight degrees of freedom Higgs field. However analyzing the same situation using sub groups of the largest exceptional Lie group leads to the conclusion that we are likely to find three Higgs particles only at the energy scale of the standard model. Consequently five of the eight degrees of freedom are unlikely to materialize as particles at this particular energy scale. This conclusion is reinforced by an entirely different approach based on grand unification analysis which excludes any grand unification using 4HD, i.e. four Higgs doublets. This leaves us with one, two and three Higgs doublets. Noting that a super symmetric standard model with two Higgs doublets gives almost perfect grand unification and that the result agrees with our exceptional Lie symmetry groups analysis, we exclude everything else. The final result is that we expect to find at least three more Higgs particles leading to a total of 66 elementary particles while at a somewhat higher energy, the expected number of 69 particles found using E-infinity theory is obtained

Gauge coupling unification in superstring derived standard-like models

International Nuclear Information System (INIS)

Faraggi, A.E.

1992-11-01

I discuss gauge coupling unification in a class of superstring standard-like models, which are derived in the free fermionic formulation. Recent calculations indicate that the superstring unification scale is at O(10 18 GeV) while the minimal supersymmetric standard model is consistent with LEP data if the unification scale is at O(10 16 )GeV. A generic feature of the superstring standard-like models is the appearance of extra color triplets (D,D), and electroweak doublets (l,l), in vector-like representations, beyond the supersymmetric standard model. I show that the gauge coupling unification at O(10 18 GeV) in the superstring standard-like models can be consistent with LEP data. I present an explicit standard-like model that can realize superstring gauge coupling unification. (author)

Minimal SUSY SO(10) and Yukawa unification

International Nuclear Information System (INIS)

Okada, Nobuchika

2013-01-01

The minimal supersymmetric (SUSY) SO(10) model, where only two Higgs multiplets {10⊕126-bar} are utilized for Yukawa couplings with matter fields, can nicely fit the neutrino oscillation parameters as well as charged fermion masses and mixing angles. In the fitting of the fermion mass matrix data, the largest element in the Yukawa coupling with the 126-bar -plet Higgs (Y 126 ) is found to be of order one, so that the right see-saw scale should be provided by Higgs vacuum expectation values (VEVs) of β(10 14 GeV). This fact causes a serious problem, namely, the gauge coupling unification is spoiled because of the presence of many exotic Higgs multiples emerging at the see-saw scale. In order to solve this problem, we consider a unification between bottom-quark and tau Yukawa couplings (b - τ Yukawa coupling unification) at the grand unified theory (GUT) scale, due to threshold corrections of superpartners to the Yukawa couplings at the 1 TeV scale. When the b - τ Yukawa coupling unification is very accurate, the largest element in Y 126 can become β(0.01), so that the right see-saw scale is realized by the GUT scale VEV and the usual gauge coupling unification is maintained. Since the b - τ Yukawa unification alters the Yukawa coupling data at the GUT scale, we re-analyze the fitting of the fermion mass matrix data by taking all the relevant free parameters into account. Unfortunately, we find that no parameter region shows up to give a nice fit for the current neutrino oscillation data and therefore, the usual picture of the gauge coupling unification cannot accommodate the fermion mass matrix data fitting in our procedure.

Decaying dark matter in supersymmetric SU(5) models

International Nuclear Information System (INIS)

Luo Mingxing; Wang Liucheng; Wu Wei; Zhu Guohuai

2010-01-01

Motivated by recent observations from PAMELA, Fermi and H.E.S.S., we consider dark matter decays in the framework of supersymmetric SU(5) grand unification theories. An SU(5) singlet S is assumed to be the main component of dark matters, which decays into visible particles through dimension six operators suppressed by the grand unification scale. Under certain conditions, S decays dominantly into a pair of sleptons with universal coupling for all generations. Subsequently, electrons and positrons are produced from cascade decays of these sleptons. These cascade decay chains smooth the e + +e - spectrum, which permit naturally a good fit to the Fermi-LAT data. The observed positron fraction upturn by PAMELA can be reproduced simultaneously. We have also calculated diffuse gamma-ray spectra due to the e ± excesses and compared them with the preliminary Fermi-LAT data from 0.1 GeV to 10 GeV in the region 0 deg. ≤l≤ 360 deg., 10 deg. ≤|b|≤20 deg. The photon spectrum of energy above 100 GeV, mainly from final state radiations, may be checked in the near future.

Grand unified supersymmetric Higgs bosons as pseudo-Goldstone particles

International Nuclear Information System (INIS)

Barbieri, R.; Dvali, G.; Strumia, A.

1993-01-01

We reconsider the possibility that the Higgs doublet responsible for the breaking of the electroweak gauge group be quasi-Goldstone bosons of a spontaneously broken approximate global symmetry of the theory. Supersymmetric SU(5) and SO(10) gauge models are discussed. The main phenomenological consequence of this viewpoint is the possible existence at the Fermi scale of a quasi-stable particle, most likely a Lorentz scalar, with the same colour and charge as a down quark. Its existence is a generic feature of models based on SO(10). The associated phenomoenological is illustrated. We also show how the phenomenology of the minimal SU(5) theory, already proposed, gets tightly constrained by the consideration of coupling constant unification without any assumption, otherwise crucial, on the superheavy threshold effects. (orig.)

Hierarchy of symmetry-breaking scales in SO(10) grand unification and particle masses

International Nuclear Information System (INIS)

Asatryan, G.M.; Ioannisyan, A.N.

1987-01-01

An SO(10) grand unification model is proposed in which the introduction of an additional discrete symmetry solves the problem of the quark mass spectrum arising in SO(10) breaking schemes with intermediate SU(4) x SU(2)/sub L/ x SU(2)/sub R/ or SU(3)/sub C/ x U(1)/sub B//sub -//sub L/ x SU(2)/sub L/ x SU(2)/sub R/ symmetry. When the breaking of this discrete symmetry is taken into account the condition that there exist only a single light Higgs boson leads to a relation between the b- and t-quark masses which makes it possible to fix the ratio of the grand unification scale M/sub X/ and the quark--lepton symmetry-breaking scale M/sub C/. The specific values of M/sub X/ and M/sub C/ and also the scale of the SU(2)/sub R/ symmetry breaking M/sub R/ depend on the experimental value of the Weinberg angle and are in agreement with the experimental data on proton decay

Relict gravitational waves in the expanding Universe model and the grand unification scale

International Nuclear Information System (INIS)

Veryskin, A.V.; Rubakov, V.A.; Sazhin, M.V.

1983-01-01

The amplification of the vacuum fluctuations of the metric in the model of the expanding Universe was considered. The spectrum of the relict gravitational waves was chosen to be independent from the details of an evolution of the Universe after the phase transition. It is shown that the expanding Universe scenario is compatible with the experimental data on the anisotropy of the microwave background only if the vacuum energy density of the symmetric phase is much less than the Planck one. The theories of grand unification with not large values of the unification scale (one and a half order less than the Planck mass) are preferable from the point of view of cosmology

Symmetry Breaking, Unification, and Theories Beyond the Standard Model

Energy Technology Data Exchange (ETDEWEB)

Nomura, Yasunori

2009-07-31

A model was constructed in which the supersymmetric fine-tuning problem is solved without extending the Higgs sector at the weak scale. We have demonstrated that the model can avoid all the phenomenological constraints, while avoiding excessive fine-tuning. We have also studied implications of the model on dark matter physics and collider physics. I have proposed in an extremely simple construction for models of gauge mediation. We found that the {mu} problem can be simply and elegantly solved in a class of models where the Higgs fields couple directly to the supersymmetry breaking sector. We proposed a new way of addressing the flavor problem of supersymmetric theories. We have proposed a new framework of constructing theories of grand unification. We constructed a simple and elegant model of dark matter which explains excess flux of electrons/positrons. We constructed a model of dark energy in which evolving quintessence-type dark energy is naturally obtained. We studied if we can find evidence of the multiverse.

Supersymmetric grand unified theories and cosmology

International Nuclear Information System (INIS)

Lazarides, G.; Shafi, Q.

1983-01-01

By examining the behavior of supersymmetric grand unified theories (GUT's) in the very early universe we find two classes of realistic models. In one of them supersymmetry is broken at or near superheavy GUT scale. The cosmological implications of such models are expected to be similar to those of nonsupersymmetric GUT's. In the second class of models, the superheavy GUT scale is related to the supersymmetry-breaking scale in the manner of Witten. Two types of cosmological scenarios appear possible in this case, either with or without an intermediate (new) inflationary phase. They can be experimentally distinguished, since the former predicts an absence and the latter an observable number density of superheavy monopoles. A mechanism for generating baryon asymmetry in such models is pointed out

Unification of SUSY breaking and GUT breaking

Energy Technology Data Exchange (ETDEWEB)

Kobayashi, Tatsuo [Department of Physics, Hokkaido University,Sapporo 060-0810 (Japan); Omura, Yuji [Department of Physics, Nagoya University,Nagoya 464-8602 (Japan)

2015-02-18

We build explicit supersymmetric unification models where grand unified gauge symmetry breaking and supersymmetry (SUSY) breaking are caused by the same sector. Besides, the SM-charged particles are also predicted by the symmetry breaking sector, and they give the soft SUSY breaking terms through the so-called gauge mediation. We investigate the mass spectrums in an explicit model with SU(5) and additional gauge groups, and discuss its phenomenological aspects. Especially, nonzero A-term and B-term are generated at one-loop level according to the mediation via the vector superfields, so that the electro-weak symmetry breaking and 125 GeV Higgs mass may be achieved by the large B-term and A-term even if the stop mass is around 1 TeV.

Supersymmetric models with tan β close to unity

International Nuclear Information System (INIS)

Ananthanarayan, B.; Babu, K.S.; Shafi, Q.

1994-01-01

Within the framework of supersymmetric grand unification, estimates of the b quark mass based on the asymptotic relation m b similar eqm τ single out the region with tan β close to unity, particularly if m t (m t ) < or ∼170 GeV. We explore the radiative breaking of the electroweak symmetry and the associated sparticle and higgs spectroscopy in models with 1 < tan β< or ∼1.6. The lightest scalar higgs is expected to have a mass below 100 GeV, while the remaining four higgs masses exceed 300 GeV. The lower bounds on some of the sparticle masses are within the range of LEP 200. ((orig.))

Small numbers in supersymmetric theories of nature

International Nuclear Information System (INIS)

Graesser, Michael L.

1999-01-01

The Standard Model of particle interactions is a successful theory for describing the interactions of quarks, leptons and gauge bosons at microscopic distance scales. Despite these successes, the theory contains many unsatisfactory features. The origin of particle masses is a central mystery that has eluded experimental elucidation. In the Standard Model the known particles obtain their mass from the condensate of the so-called Higgs particle. Quantum corrections to the Higgs mass require an unnatural fine tuning in the Higgs mass of one part in 10 -32 to obtain the correct mass scale of electroweak physics. In addition, the origin of the vast hierarchy between the mass scales of the electroweak and quantum gravity physics is not explained in the current theory. Supersymmetric extensions to the Standard Model are not plagued by this fine tuning issue and may therefore be relevant in Nature. In the minimal supersymmetric Standard Model there is also a natural explanation for electroweak symmetry breaking. Supersymmetric Grand Unified Theories also correctly predict a parameter of the Standard Model. This provides non-trivial indirect evidence for these theories. The most general supersymmetric extension to the Standard Model however, is excluded by many physical processes, such as rare flavor changing processes, and the non-observation of the instability of the proton. These processes provide important information about the possible structure such a theory. In particular, certain parameters in this theory must be rather small. A physics explanation for why this is the case would be desirable. It is striking that the gauge couplings of the Standard Model unify if there is supersymmetry close to the weak scale. This suggests that at high energies Nature is described by a supersymmetric Grand Unified Theory. But the mass scale of unification must be introduced into the theory since it does not coincide with the probable mass scale of strong quantum gravity. The subject

On two-particle N=1 supersymmetric composite grand unified models

International Nuclear Information System (INIS)

Pirogov, Yu.F.

1984-01-01

A class of two-particle N=1 supersymmetric composite grand unified models, satisfying the anomaly matching and cancellation conditions, n-independence and survival hypothesis is considered. A unique admissible set of the light states, containing spectator states on a par with the composite ones is found. At low mass scales this set contains exactly four families of ordinary fermions without any additional exotics. The interactions of the light states at distances greater than the compositeness radius are described by the N=1 sypersymmetric chiral grand unified model [SU(6)] 2 (or [SU(8)] 2 with a fixed set of four second-rank tensors as matter fields

An approach to gauge hierarchy in the minimal SU(5) model of grand unification

International Nuclear Information System (INIS)

Ghose, P.

1982-08-01

It is shown that if all mass generation through spontaneous symmetry breaking is predominantly caused by scalar loops in the minimal SU(5) model of grand unification, it is possible to have an arbitrarily large gauge hierarchy msub(x) >> msub(w) with all Higgs bosons superheavy. No fine tuning is necessary in every order. (author)

Scalar mass relations and flavor violations in supersymmetric theories

International Nuclear Information System (INIS)

Cheng, Hsin-Chia; California Univ., Berkeley, CA

1996-01-01

Supersymmetry provides the most promising solution to the gauge hierarchy problem. For supersymmetry to stablize the hierarchy, it must be broken at the weak scale. The combination of weak scale supersymmetry and grand unification leads to a successful prediction of the weak mixing angle to within 1% accuracy. If supersymmetry is a symmetry of nature, the mass spectrum and the flavor mixing pattern of the scalar superpartners of all the quarks and leptons will provide important information about a more fundamental theory at higher energies. We studied the scalar mass relations which follow from the assumption that at high energies there is a grand unified theory which leads to a significant prediction of the weak mixing angle; these will serve as important tests of grand unified theories. Two intragenerational mass relations for each of the light generations are derived. A third relation is also found which relates the Higgs masses and the masses of all three generation scalars. In a realistic supersymmetric grand unified theory, nontrivial flavor mixings are expected to exist at all gaugino vertices. This could lead to important contributions to the neutron electric dipole moment, the decay mode p → K 0 μ + , weak scale radiative corrections to the up-type quark masses, and lepton flavor violating signals such as μ → eγ. These also provide important probes of physics at high energy scales. Supersymmetric theories involving a spontaneously broken flavor symmetry can provide a solution to the supersymmetric flavor-changing problem and an understanding of the fermion masses and mixings. We studied the possibilities and the general conditions under which some fermion masses and mixings can be obtained radiatively. We also constructed theories of flavor in which the first generation fermion masses arise from radiative corrections while flavor-changing constraints are satisfied. 69 refs., 19 figs., 9 tabs

LEP constraints on grand unified theories

International Nuclear Information System (INIS)

Sarkar, Utpal

1993-01-01

Recent developments on grand unified theories (GUTs) in the context of the LEP measurements of the coupling constants are reviewed. The three coupling constants at the electroweak scale have been measured at LEP quite precisely. One can allow these couplings to evolve with energy following the renormalization group equations for the various groups and find out whether all the coupling constants meet at any energy. It was pointed out that the minimal SU(5) grand unified theory fails to satisfy this test. However, various extensions of the theory are still allowed. These extensions include (i) supersymmetric SU(5) GUT, with some arbitrariness in the susy breaking scale arising from the threshold corrections, (ii) non-susy SU(5) GUTs with additional fermions as well as Higgs multiplets, which has masses of the order of TeV, and (iii) non-renormalizable effect of gravity with a fine tuned relation among the coupling constants at the unification energy. The LEP results also constrain GUTs with an intermediate symmetry breaking scale. By adjusting the intermediate symmetry breaking scale, one usually can have unification, but these theories get constrained. For example, the left-right symmetric theories coming from GUTs can be broken only at energies higher than about ∼10 10 GeV. This implies that if right handed gauge bosons are found at energies lower than this scale, then that will rule out the possibility of grand unification. Another recent interesting development on the subject, namely, low energy unification, is discussed in this context. All the coupling constants are unified at energies of the order of ∼10 8 GeV when they are embedded in an SU(15)GUT, with some particular symmetry breaking pattern. But even in this case the results of the intermediate symmetry breaking scale remain unchanged. (author). 16 refs., 3 figs

Supersymmetric family unification

International Nuclear Information System (INIS)

Frampton, P.H.; Kephart, T.W.

1983-01-01

The superheavy symmetry breaking of the gauge group in supersymmetrized unified theories is studied. The requirement that supersymmetry be unbroken strongly constrains the possible gauge group breaking, and we systematize such constraints group theoretically. In model building, one issue is whether to permit an adjoint matter superfield with concomitant color exotic fermions. A second issue is that of naturalness which is complicated by the well-known supersymmetry non-renormalization theorems. Both with and without an adjoint matter superfield, the most promising group appears to be SU(9) where three families can be naturally accommodated, at least for low-energy gauge group SU(3) x SU(2) x U(1). With an extra U(1) factor, as advocated by Fayet, the non-renormalization theorem must be exploited. (orig.)

Implications of results from the CERN e+e- collider LEP for SO(10) grand unification with two intermediate stages

International Nuclear Information System (INIS)

Deshpande, N.G.; Keith, E.; Pal, P.B.

1993-01-01

We consider the breaking of the grand unification group SO(10) to the standard model gauge group through several chains containing two intermediate stages. Using the values of the gauge coupling constants at a scale M Z derived from recent data from the CERN e + e- collider LEP, we determine the range of their intermediate and unification scales. In particular, we identify those chains that permit new gauge structure at relatively low energy (∼1 TeV)

Loopholes in Z ' searches at the LHC: exploring supersymmetric and leptophobic scenarios

Science.gov (United States)

Araz, Jack Y.; Corcella, Gennaro; Frank, Mariana; Fuks, Benjamin

2018-02-01

Searching for heavy vector bosons Z ', predicted in models inspired by Grand Unification Theories, is among the challenging objectives of the LHC. The ATLAS and CMS collaborations have looked for Z ' bosons assuming that they can decay only into Standard Model channels, and have set exclusion limits by investigating dilepton, dijet and, to a smaller extent, top-antitop final states. In this work we explore possible loopholes in these Z ' searches, by studying supersymmetric as well as leptophobic scenarios. We demonstrate the existence of realizations in which the Z ' boson automatically evades the typical bounds derived from the analyses of the Drell-Yan invariant-mass spectrum. Dileptonic final states can in contrast only originate from supersymmetric Z ' decays and are thus accompanied by additional effects. This feature is analyzed in the context of judiciously chosen bench-mark configurations, for which visible signals could be expected in future LHC data with a 4 σ - 7 σ significance. Our results should hence motivate an extension of the current Z ' search program to account for supersymmetric and leptophobic models.

Grand unification and the fundamental problems of classical cosmology

International Nuclear Information System (INIS)

Turner, M.S.

1981-01-01

The accomplishments of classical cosmology are reviewed. In particular, the hot big bang model provides a reliable framework for understanding the evolution of the universe back to times at least as early as approx. 0.01 s after the big bang. At present there are (at least) six fundamental problems which have not yet been (completely) resolved. They are: (1) the origin of the baryon number-to-entropy ratio, (2) the origin of the isotropy, (3) the origin of the homogeneity and inhomogeneity, (4) the origin of the flatness, (5) the cosmological constant, and (6) the monopole problem. The role that grand unification has played, and may play in the resolution of these puzzles is discussed. Guth's inflationary universe, which addresses five of these six problems, is reviewed

Unification beyond GUT's: Gauge-Yukawa unification

International Nuclear Information System (INIS)

Kubo, J.; Mondragon, M.; Zoupanos, G.

1996-01-01

Gauge-Yukawa Unification (GYU) is a renormalization group invariant functional relation among gauge and Yukawa couplings which holds beyond the unification point in Grand Unified Theories (GUTs). We present here various models where GYU is obtained by requiring the principles of finiteness and reduction of couplings. We examine the consequences of these requirements for the low energy parameters, especially for the top quark mass. The predictions are such that they clearly distinguish already GYU from ordinary GUTs. It is expected that it will be possible to discriminate among the various GYUs when more accurate measurements of the top quark mass are available. (author)

Gauge coupling unification in realistic free-fermionic string models

International Nuclear Information System (INIS)

Dienes, K.R.; Faraggi, A.E.

1995-01-01

We discuss the unification of gauge couplings within the framework of a wide class of realistic free-fermionic string models which have appeared in the literature, including the flipped SU(5), SO(6)xSO(4), and various SU(3)xSU(2)xU(1) models. If the matter spectrum below the string scale is that of the Minimal Supersymmetric Standard Model (MSSM), then string unification is in disagreement with experiment. We therefore examine several effects that may modify the minimal string predictions. First, we develop a systematic procedure for evaluating the one-loop heavy string threshold corrections in free-fermionic string models, and we explicitly evaluate these corrections for each of the realistic models. We find that these string threshold corrections are small, and we provide general arguments explaining why such threshold corrections are suppressed in string theory. Thus heavy thresholds cannot resolve the disagreement with experiment. We also study the effect of non-standard hypercharge normalizations, light SUSY thresholds, and intermediate-scale gauge structure, and similarly conclude that these effects cannot resolve the disagreement with low-energy data. Finally, we examine the effects of additional color triplets and electroweak doublets beyond the MSSM. Although not required in ordinary grand unification scenarios, such states generically appear within the context of certain realistic free-fermionic string models. We show that if these states exist at the appropriate thresholds, then the gauge couplings will indeed unify at the string scale. Thus, within these string models, string unification can be in agreement with low-energy data. (orig.)

Two-loop renormalization group analysis of supersymmetric SO(10) models with an intermediate scale

International Nuclear Information System (INIS)

Bastero-Gil, M.; Brahmachari, B.

1996-03-01

Two-loop evolutions of the gauge couplings in a class of intermediate scale supersymmetric SO(10) models including the effect of third generation Yukawa couplings are studied. The unification scale, the intermediate scale and the value of the unification gauge coupling in these models are calculated and the gauge boson mediated proton decay rates are estimated. In some cases the predicted proton lifetime turns out to be in the border-line of experimental limit. The predictions of the top quark mass, the mass ratio m b (m b )/m τ (m τ ) from the two-loop evolution of Yukawa couplings and the mass of the left handed neutrino via see-saw mechanism are summarized. The lower bounds on the ratio of the VEVs of the two low energy doublets (tan β) from the requirement of the perturbative unitarity of the top quark Yukawa coupling up to the grand unification scale are also presented. All the predictions have been compared with those of the one-step unified theory. (author). 33 refs, 5 figs, 1 tab

Dark matter as the signal of grand unification

International Nuclear Information System (INIS)

Kadastik, Mario; Kannike, Kristjan; Raidal, Martti

2009-01-01

We argue that the existence of dark matter (DM) is a possible consequence of grand unification (GUT) symmetry breaking. In GUTs like SO(10), discrete Z 2 matter parity (-1) 3(B-L) survives despite broken B-L, and group theory uniquely determines that the only possible Z 2 -odd matter multiplets belong to representation 16. We construct the minimal nonsupersymmetric SO(10) model containing one scalar 16 for DM and study its predictions below M G . We find that electroweak symmetry breaking occurs radiatively due to DM couplings to the standard model Higgs boson. For thermal relic DM the mass range M DM ∼O(0.1-1) TeV is predicted by model perturbativity up to M G . For M DM ∼O(1) TeV to explain the observed cosmic ray anomalies with DM decays, there exists a lower bound on the spin-independent direct detection cross section within the reach of planned experiments.

Probing the design of grand unification through conservation laws

International Nuclear Information System (INIS)

Pati, J.C.

1981-01-01

The purpose of this talk is to note a few special consequences of gauging ''maximal'' quark-lepton symmetries such as SO(16), which is the maximal symmetry for a single family of fermions. Within these symmetries, violations for B, L and F are spontaneous rather than explicit. Furthermore these symmetries as a rule permit intermediate mass scales approx.(10 3 -10 6 GeV) and (10 8 -10 11 GeV) filling the so-called grand plateau between 10 2 and 10 15 GeV. It has been shown in earlier papers that within these symmetries proton may decay via four alternative models: i.e. proton→one or three leptons or antileptons plus mesons; some of which can coexist. It is now observed that even n-n-bar oscillations can coexist with (B-L) conserving proton-decays of the type p→e + π 0 etc. without posing any conflict with the cosmological generation of baryon-excess; both these processes can possess measurable strengths so as to be amenable to forthcoming searches. Search for alternative decay modes of proton and n-n-bar oscillations, even as processes in second and third generation experiments, would provide valuable information on the question of intermediate mass-scales and thereby on the design of grand unification

Finite Unification: Theory, Models and Predictions

CERN Document Server

Heinemeyer, S; Zoupanos, G

2011-01-01

All-loop Finite Unified Theories (FUTs) are very interesting N=1 supersymmetric Grand Unified Theories (GUTs) realising an old field theory dream, and moreover have a remarkable predictive power due to the required reduction of couplings. The reduction of the dimensionless couplings in N=1 GUTs is achieved by searching for renormalization group invariant (RGI) relations among them holding beyond the unification scale. Finiteness results from the fact that there exist RGI relations among dimensional couplings that guarantee the vanishing of all beta-functions in certain N=1 GUTs even to all orders. Furthermore developments in the soft supersymmetry breaking sector of N=1 GUTs and FUTs lead to exact RGI relations, i.e. reduction of couplings, in this dimensionful sector of the theory, too. Based on the above theoretical framework phenomenologically consistent FUTs have been constructed. Here we review FUT models based on the SU(5) and SU(3)^3 gauge groups and their predictions. Of particular interest is the Hig...

Asymptotically Safe Grand Unification

DEFF Research Database (Denmark)

Bajc, Borut; Sannino, Francesco

2016-01-01

the inclusion of gravity, by generating an interacting ultraviolet fixed point, similar to the one recently discovered in non-supersymmetric gauge-Yukawa theories. Employing a-maximization, a-theorem, unitarity bounds, as well as positivity of other central charges we nonperturbatively rule out this possibility...

Softening the supersymmetric flavor problem in orbifold grand unified theories

International Nuclear Information System (INIS)

Kajiyama, Yuji; Terao, Haruhiko; Kubo, Jisuke

2004-01-01

The infrared attractive force of the bulk gauge interactions is applied to soften the supersymmetric flavor problem in the orbifold SU(5) grand unified theory of Kawamura. Then this force aligns in the infrared regime the soft supersymmetry breaking terms out of their anarchical disorder at a fundamental scale, in such a way that flavor-changing neutral currents as well as dangerous CP-violating phases are suppressed at low energies. It is found that this dynamical alignment is sufficiently good compared with the current experimental bounds, as long as the diagonalization matrices of the Yukawa couplings are CKM-like

Gauge Coupling Unification with Partly Composite Matter

International Nuclear Information System (INIS)

Gherghetta, Tony

2005-01-01

It is shown how gauge coupling unification can occur in models with partly composite matter. The particle states which are composite only contribute small logarithmns to the running of gauge couplings, while the elementary states contribute the usual large logarithmns. This introduces a new differential running contribution to the gauge couplings from partly composite SU(5) matter multiplets. In particular, for partly supersymmetric models, the incomplete SU(5) elementary matter multiplets restore gauge coupling unification even though the usual elementary gaugino and Higgsino contributions need not be present

Restrictions on two Higgs doublet models and CP violation at the unification scale

International Nuclear Information System (INIS)

Athanasiu, G.G.

1987-04-01

Bounds on charged Higgs masses and couplings in models with two Higgs doublets are examined that came from CP violation in the neutral K system. Bounds on charged Higgs masses and couplings in two Higgs doublet models are also obtained from their effects on neutral-B-meson mixing. The bounds are found to be comparable to those obtained with additional assumptions from the neutral K system. The three generation phase invariant measure of CP violation is shown to satisfy a simple and solvable renormalization group equation. Its value is seen to fall by four to eight orders of magnitude between the weak and grand unification scales in the standard model, as well as in its two Higgs and supersymmetric extensions

Higgs Inflation, Reheating and Gravitino Production in No-Scale Supersymmetric GUTs

CERN Document Server

Ellis, John; Xianyu, Zhong-Zhi

2016-08-30

We extend our previous study of supersymmetric Higgs inflation in the context of no-scale supergravity and grand unification, to include models based on the flipped SU(5) and the Pati-Salam group. Like the previous SU(5) GUT model, these yield a class of inflation models whose inflation predictions interpolate between those of the quadratic chaotic inflation and Starobinsky-like inflation, while also avoiding tension with proton decay limits. We further analyse the reheating process in these models, and derive the number of $e$-folds, which is independent of the reheating temperature. We derive the corresponding predictions for the scalar tilt and the tensor-to-scalar ratio in cosmic microwave background perturbations, and also discuss gravitino production following inflation.

Higgs inflation, reheating and gravitino production in no-scale Supersymmetric GUTs

Energy Technology Data Exchange (ETDEWEB)

Ellis, John [Theoretical Particle Physics and Cosmology Group,Department of Physics, King’s College London,London WC2R 2LS (United Kingdom); Theoretical Physics Department, CERN,CH-1211 Geneva 23 (Switzerland); He, Hong-Jian [Institute of Modern Physics and Center for High Energy Physics, Tsinghua University,Beijing 100084 (China); Center for High Energy Physics, Peking University,Beijing 100871 (China); Xianyu, Zhong-Zhi [Center of Mathematical Sciences and Applications andDepartment of Physics, Harvard University,Massachusetts 02138 (United States)

2016-08-30

We extend our previous study of supersymmetric Higgs inflation in the context of no-scale supergravity and grand unification, to include models based on the flipped SU(5) and the Pati-Salam group. Like the previous SU(5) GUT model, these yield a class of inflation models whose inflation predictions interpolate between those of the quadratic chaotic inflation and Starobinsky-like inflation, while avoiding tension with proton decay limits. We further analyse the reheating process in these models, and derive the number of e-folds, which is independent of the reheating temperature. We derive the corresponding predictions for the scalar tilt and the tensor-to-scalar ratio in cosmic microwave background perturbations, as well as discussing the gravitino production following inflation.

Early universe cosmology. In supersymmetric extensions of the standard model

International Nuclear Information System (INIS)

Baumann, Jochen Peter

2012-01-01

In this thesis we investigate possible connections between cosmological inflation and leptogenesis on the one side and particle physics on the other side. We work in supersymmetric extensions of the Standard Model. A key role is played by the right-handed sneutrino, the superpartner of the right-handed neutrino involved in the type I seesaw mechanism. We study a combined model of inflation and non-thermal leptogenesis that is a simple extension of the Minimal Supersymmetric Standard Model (MSSM) with conserved R-parity, where we add three right-handed neutrino super fields. The inflaton direction is given by the imaginary components of the corresponding scalar component fields, which are protected from the supergravity (SUGRA) η-problem by a shift symmetry in the Kaehler potential. We discuss the model first in a globally supersymmetric (SUSY) and then in a supergravity context and compute the inflationary predictions of the model. We also study reheating and non-thermal leptogenesis in this model. A numerical simulation shows that shortly after the waterfall phase transition that ends inflation, the universe is dominated by right-handed sneutrinos and their out-of-equilibrium decay can produce the desired matter-antimatter asymmetry. Using a simplified time-averaged description, we derive analytical expressions for the model predictions. Combining the results from inflation and leptogenesis allows us to constrain the allowed parameter space from two different directions, with implications for low energy neutrino physics. As a second thread of investigation, we discuss a generalisation of the inflationary model discussed above to include gauge non-singlet fields as inflatons. This is motivated by the fact that in left-right symmetric, supersymmetric Grand Unified Theories (SUSY GUTs), like SUSY Pati-Salam unification or SUSY SO(10) GUTs, the righthanded (s)neutrino is an indispensable ingredient and does not have to be put in by hand as in the MSSM. We discuss the

Early universe cosmology. In supersymmetric extensions of the standard model

Energy Technology Data Exchange (ETDEWEB)

Baumann, Jochen Peter

2012-03-19

In this thesis we investigate possible connections between cosmological inflation and leptogenesis on the one side and particle physics on the other side. We work in supersymmetric extensions of the Standard Model. A key role is played by the right-handed sneutrino, the superpartner of the right-handed neutrino involved in the type I seesaw mechanism. We study a combined model of inflation and non-thermal leptogenesis that is a simple extension of the Minimal Supersymmetric Standard Model (MSSM) with conserved R-parity, where we add three right-handed neutrino super fields. The inflaton direction is given by the imaginary components of the corresponding scalar component fields, which are protected from the supergravity (SUGRA) {eta}-problem by a shift symmetry in the Kaehler potential. We discuss the model first in a globally supersymmetric (SUSY) and then in a supergravity context and compute the inflationary predictions of the model. We also study reheating and non-thermal leptogenesis in this model. A numerical simulation shows that shortly after the waterfall phase transition that ends inflation, the universe is dominated by right-handed sneutrinos and their out-of-equilibrium decay can produce the desired matter-antimatter asymmetry. Using a simplified time-averaged description, we derive analytical expressions for the model predictions. Combining the results from inflation and leptogenesis allows us to constrain the allowed parameter space from two different directions, with implications for low energy neutrino physics. As a second thread of investigation, we discuss a generalisation of the inflationary model discussed above to include gauge non-singlet fields as inflatons. This is motivated by the fact that in left-right symmetric, supersymmetric Grand Unified Theories (SUSY GUTs), like SUSY Pati-Salam unification or SUSY SO(10) GUTs, the righthanded (s)neutrino is an indispensable ingredient and does not have to be put in by hand as in the MSSM. We discuss

Minimal supersymmetric grand unified theory: Symmetry breaking and the particle spectrum

International Nuclear Information System (INIS)

Bajc, Borut; Melfo, Alejandra; Senjanovic, Goran; Vissani, Francesco

2004-01-01

We discuss in detail the symmetry breaking and related issues in the minimal renormalizable supersymmetric grand unified theory. We find all the possible patterns of symmetry breaking, compute the associated particle spectrum and study its impact on the physical scales of the theory. In particular, the complete mass matrices of the SU(2) doublets and the color triplets are computed in connection with the doublet-triplet splitting and the d=5 proton decay. We explicitly construct the two light Higgs doublets as a function of the Higgs superpotential parameters. This provides a framework for the analysis of phenomenological implications of the theory, to be carried out in a second paper

New fat Higgs: Increasing the MSSM Higgs mass with natural gauge unification

International Nuclear Information System (INIS)

Chang, Spencer; Kilic, Can; Mahbubani, Rakhi

2005-01-01

In this paper we increase the minimal supersymmetric standard model tree level Higgs mass bound to a value that is naturally larger than the LEP-II search constraint by adding to the superpotential a λSH u H d term, as in the next to minimal supersymmetric standard model, and UV completing with new strong dynamics before λ becomes nonperturbative. Unlike other models of this type, the Higgs fields remain elementary, alleviating the supersymmetric fine-tuning problem while maintaining unification in a natural way

Electroweak symmetry breaking and mass spectra in six-dimensional gauge-Higgs grand unification

Science.gov (United States)

Hosotani, Yutaka; Yamatsu, Naoki

2018-02-01

The mass spectra of the standard model particles are reproduced in the SO(11) gauge-Higgs grand unification in six-dimensional warped space without introducing exotic light fermions. Light neutrino masses are explained by the gauge-Higgs seesaw mechanism. We evaluate the effective potential of the four-dimensional Higgs boson appearing as a fluctuation mode of the Aharonov-Bohm phase θ_H in the extra-dimensional space, and show that the dynamical electroweak symmetry breaking takes place with the Higgs boson mass m_H ˜ 125 GeV and θ_H ˜ 0.1. The Kaluza-Klein mass scale in the fifth dimension is approximately given by m_KK ˜ 1.230 TeV/sin θ_H.

Logarithmic unification from symmetries enhanced in the sub-millimeter infrared

International Nuclear Information System (INIS)

Arkani-Hamed, Nima; Dimopoulos, Savas; March-Russell, John

1999-01-01

In theories with TeV string scale and sub-millimeter extra dimensions the attractive picture of logarithmic gauge coupling unification at 10 16 GeV is seemingly destroyed. In this paper we argue to the contrary that logarithmic unification can occur in such theories. The rationale for unification is no longer that a gauge symmetry is restored at short distances, but rather that a geometric symmetry is restored at large distances in the bulk away from our 3-brane. The apparent ''running'' of the gauge couplings to energies far above the string scale actually arises from the logarithmic variation of classical fields in (sets of) two large transverse dimensions. We present a number of N = 2 and N = 1 supersymmetric D-brane constructions illustrating this picture for unification

Grand unification and the double beta-decay

International Nuclear Information System (INIS)

Faessler, A.

1992-01-01

Models of the unification of the electroweak and the strong interaction predict that the neutrino is a Majorana particle and therefore essentially identical with its own antiparticle. In such grand unified models the neutrino has also a finite mass and a slight right-handed weak interaction, since the model is left-right symmetric. These models have also left handed and right-handed vector bosons to mediate the weak interactions. If these models are correct the neutrinoless double beta-decay is feasable. Thus if one finds the neutrinoless double beta-decay one knows that the standard model can not be correct in which the neutrino is a Dirac particle and therefore different from its antiparticle. Although the neutrinoless double beta-decay has not been seen it is possible to extract from the lower limits of the lifetime against the double neutrinoless beta-decay upper limits for the effective electron-neutrino mass and for the effective mixing angle of the right-handed and the left-handed vector bosons mediating the weak interaction. One also can obtain an effective upper limit for the mass ratio of the light and the heavy vector bosons. The extraction of this physical quantities from the data is made difficult due to the fact that the weak interaction must not be diagonal in the representation of the mass matrix of the six neutrinos requested by such left-right symmetric models. (author)

Flavour Democracy in Strong Unification

CERN Document Server

Abel, S A; Abel, Steven; King, Steven

1998-01-01

We show that the fermion mass spectrum may naturally be understood in terms of flavour democratic fixed points in supersymmetric theories which have a large domain of attraction in the presence of "strong unification". Our approach provides an alternative to the approximate Yukawa texture zeroes of the Froggatt-Nielsen mechanism. We discuss a particular model based on a broken gauged $SU(3)_L\\times SU(3)_R$ family symmetry which illustrates our approach.

Supersymmetric mechanics

International Nuclear Information System (INIS)

Stelle, Kellogg S

2007-01-01

With the development of the electronic archives in high-energy physics, there has been increasing questioning of the role of traditional publishing styles, particularly in the production of conference books. One aspect of traditional publishing that still receives wide appreciation, however, is in the production of well-focussed pedagogical material. The present two-volume edition, 'Supersymmetric Mechanics-Vol 1', edited by S Bellucci and 'Supersymmetric Mechanics-Vol 2', edited by S Bellucci, S Ferrara and A Marrani, is a good example of the kind of well-digested presentation that should still find its way into university libraries. This two-volume set presents the material of a set of pedagogical lectures presented at the INFN National Laboratory in Frascati over a two-year period on the subject of supersymmetric mechanics. The articles include the results of discussions with the attending students after the lectures. Overall, this makes for a useful compilation of material on a subject that underlies much of the current effort in supersymmetric approaches to cosmology and the unification programme. The first volume comprises articles on 'A journey through garden algebras' by S Bellucci, S J Gates Jr and E Orazi on linear supermultiplet realizations in supersymmetric mechanics,'Supersymmetric mechanics in superspace' by S Bellucci and S Krivonos, 'Noncommutative mechanics, Landau levels, twistors and Yang-Mills amplitudes' by V P Nair, 'Elements of (super) Hamiltonian formalism' by A Nersessian and 'Matrix mechanics' by C Sochichiu. The second volume consists entirely of a masterful presentation on 'The attractor mechanism and space time singularities' by S Ferrara. This presents a comprehensive and detailed overview of the structure of supersymmetric black hole solutions in supergravity, critical point structure in the scalar field moduli space and the thermodynamic consequences. This second volume alone makes the set a worthwhile addition to the research

Sfermion mass degeneracy, superconformal dynamics, and supersymmetric grand unified theories

International Nuclear Information System (INIS)

Kobayashi, Tatsuo; Noguchi, Tatsuya; Nakano, Hiroaki; Terao, Haruhiko

2002-01-01

We discuss issues in a scenario where hierarchical Yukawa couplings are generated through the strong dynamics of superconformal field theories (SCFTs). Independently of the mediation mechanism of supersymmetry breaking, the infrared convergence property of SCFTs can provide an interesting solution to the supersymmetric flavor problem; sfermion masses are suppressed around the decoupling scale of SCFTs and eventually become degenerate to some degree, thanks to family-independent radiative corrections governed by the gaugino masses of the minimal supersymmetric standard model (MSSM). We discuss under what conditions the degeneracy of the sfermion mass can be estimated in a simple manner. We also discuss the constraints from lepton flavor violations. We then explicitly study sfermion mass degeneracy within the framework of grand unified theories coupled to SCFTs. It is found that the degeneracy for right-handed sleptons becomes worse in the conventional SU(5) model than in the MSSM. On the other hand, in the flipped SU(5)xU(1) model, each right-handed lepton is still an SU(5) singlet, whereas the B-ino mass M 1 is determined by two independent gaugino masses of SU(5)xU(1). These two properties enable us to have an improved degeneracy for the right-handed sleptons. We also speculate on how further improvement can be obtained in the SCFT approach

Supersymmetric inflation, baryon asymmetry and the gravitino problem

International Nuclear Information System (INIS)

Ovrut, B.A.; Pennsylvania Univ., Philadelphia; Steinhardt, P.J.

1984-01-01

A special class of locally supersymmetric models has been found which can produce a phase transition that meets all the conditions necessary for the inflationary universe scenario and which sets, via spontaneous supersymmetry breaking, a mass hierarchy consistent with the electroweak unification scale. In this paper we show that the same models can produce a baryon asymmetry after inflation that is consistent with astrophysical observations and can avoid the cosmological problems caused by gravitinos that appear in almost all other locally supersymmetric models. (orig.)

Implications of a heavy top in supersymmetric theories

CERN Document Server

Leontaris, George K

1995-01-01

In the context of the radiative electroweak symmetry breaking scenario we investigate the implications of a heavy top quark mass, close to its infrared fixed point, on the low energy parameters of the minimal supersymmetric standard model. We use analytic expressions to calculate the Higgs masses as well as the supersymmetric masses of the third generation. We further assume bottom-tau unification at the GUT scale and examine the constraints put by this condition on the parameter space (\\tan\\beta,\\alpha_3), using the renormalization group procedure at the two-loop level. We find only a small fraction of the parameter space where the above conditions can be satisfied, namely 1\\le \\tan\\beta \\le 2, while 0.111\\le\\alpha_3(M_Z) \\le 0.118. We further analyse the case where all three Yukawa couplings reach the perturbative limit just after the unification scale. In this latter case, the situation turns out to be very strict demanding \\tan\\beta\\sim 63.

Neutron electric dipole moment in the minimal supersymmetric standard model

International Nuclear Information System (INIS)

Inui, T.; Mimura, Y.; Sakai, N.; Sasaki, T.

1995-01-01

The neutron electric dipole moment (EDM) due to the single quark EDM and to the transition EDM is calculated in the minimal supersymmetric standard model. Assuming that the Cabibbo-Kobayashi-Maskawa matrix at the grand unification scale is the only source of CP violation, complex phases are induced in the parameters of soft supersymmetry breaking at low energies. The chargino one-loop diagram is found to give the dominant contribution of the order of 10 -27 similar 10 -29 e.cm for the quark EDM, assuming the light chargino mass and the universal scalar mass to be 50 GeV and 100 GeV, respectively. Therefore the neutron EDM in this class of model is difficult to measure experimentally. The gluino one-loop diagram also contributes due to the flavor changing gluino coupling. The transition EDM is found to give dominant contributions for certain parameter regions. (orig.)

Family unification in five and six dimensions

International Nuclear Information System (INIS)

Babu, K.S.; Barr, S.M.; Kyae, Bumseok

2002-01-01

In family unification models, all three families of quarks and leptons are grouped together into an irreducible representation of a simple gauge group, thus unifying the standard model gauge symmetries and a gauged family symmetry. Large orthogonal groups, and the exceptional groups E 7 and E 8 , have been much studied for family unification. The main theoretical difficulty of family unification is the existence of mirror families at the weak scale. It is shown here that family unification without mirror families can be realized in simple five-dimensional and six-dimensional orbifold models similar to those recently proposed for SU(5) and SO(10) grand unification. It is noted that a family unification group that survived to near the weak scale and whose coupling extrapolated to high scales unified with those of the standard model would be evidence, accessible in principle at low energy, of the existence of small (Planckian or GUT-scale) extra dimensions

Low-energy lepton violation from supersymmetric flipped SU(5)

Energy Technology Data Exchange (ETDEWEB)

Brahm, D.E.; Hall, L.J. (Physics Department, University of California, Berkeley, California 94720 (US) Theoretical Physics Group, Lawrence Berkeley Laboratory, 1 Cyclotron Road, Berkeley, California 94720)

1989-10-01

We construct a supersymmetric flipped SU(5){direct product}U(1) model which violates {ital R} parity and electron number at low energies, through a superpotential term (1/2{ital C}{sup {ital ijk}}L{sub i}L{sub j}E{sub k}{sup c}). Rotation of the electron and Higgs superfields makes this term also responsible for charged-lepton masses. The model employs a missing-partners mechanism for the Higgs fields and a seesaw mechanism for the neutrinos. It correctly predicts the approximate electron mass and several mass relations, as well as numerical values for the grand unification scale and the {ital C}{sup {ital ijk}} coefficients. The electron-neutrino Majorana mass is close to experimental limits, and provides constraints. Interesting {ital Z}{sup 0} decays are predicted: e.g., {ital Z}{sup 0}{r arrow}e{sup {minus}}{mu}{sup +}e{sup +}{mu}{sup {minus}} with invariant-mass peaks in the ({ital e},{mu}) channels.

Direct mediation, duality and unification

International Nuclear Information System (INIS)

Abel, Steven; Khoze, Valentin V.

2008-01-01

It is well-known that in scenarios with direct gauge mediation of supersymmetry breaking the messenger fields significantly affect the running of Standard Model couplings and introduce Landau poles which are difficult to avoid. Among other things, this appears to remove any possibility of a meaningful unification prediction and is often viewed as a strong argument against direct mediation. We propose two ways that Seiberg duality can circumvent this problem. In the first, which we call 'deflected-unification', the SUSY-breaking hidden sector is a magnetic theory which undergoes a Seiberg duality to an electric phase. Importantly, the electric version has fewer fundamental degrees of freedom coupled to the MSSM compared to the magnetic formulation. This changes the β-functions of the MSSM gauge couplings so as to push their Landau poles above the unification scale. We show that this scenario is realised for recently suggested models of gauge mediation based on a metastable SCQD-type hidden sector directly coupled to MSSM. The second possibility for avoiding Landau poles, which we call 'dual-unification', begins with the observation that, if the mediating fields fall into complete SU(5) multiplets, then the MSSM+messengers exhibits a fake unification at unphysical values of the gauge couplings. We show that, in known examples of electric/magnetic duals, such a fake unification in the magnetic theory reflects a real unification in the electric theory. We therefore propose that the Standard Model could itself be a magnetic dual of some unknown electric theory in which the true unification takes place. This scenario maintains the unification prediction (and unification scale) even in the presence of Landau poles in the magnetic theory below the GUT scale. We further note that this dual realization of grand unification can explain why Nature appears to unify, but the proton does not decay.

Higgsless grand unified theory breaking and trinification

International Nuclear Information System (INIS)

Carone, Christopher D.; Conroy, Justin M.

2004-01-01

Boundary conditions on an extra dimensional interval can be chosen to break bulk gauge symmetries and to reduce the rank of the gauge group. We consider this mechanism in models with gauge trinification. We determine the boundary conditions necessary to break the trinified gauge group directly down to that of the standard model. Working in an effective theory for the gauge-symmetry-breaking parameters on a boundary, we examine the limit in which the grand-unified theory-breaking-sector is Higgsless and show how one may obtain the low-energy particle content of the minimal supersymmetric standard model. We find that gauge unification is preserved in this scenario, and that the differential gauge coupling running is logarithmic above the scale of compactification. We compare the phenomenology of our model to that of four dimensional 'trinified' theories

Restrictions on two Higgs doublet models and CP violation at the unification scale

International Nuclear Information System (INIS)

Athanasiu, G.G.

1987-01-01

In Part I we examine bounds from CP violation in the neutral K system on charged Higgs masses and couplings in models with two Higgs doublets. While CP violation is still due only to a non-zero phase in the Kobayashi-Maskawa matrix, there are additional short-distance contributions involving charged Higgs exchange rather than W boson exchange. By having CP violation in the mass matrix, but not in the kaon to two pions decay amplitude, largely due to Higgs exchange, it is possible to obtain a small value of ε'/ε. In Part II we obtain bounds on charged-Higgs-boson masses and couplings in two Higgs doublet models from their effects on neutral-B-meson mixing. The bounds are comparable to those obtained with additional assumptions from the neutral-K-system. Neutral-Higgs-boson effects on the spectrum and wave functions of tt bound states are examined in the same model. In the future they could lead to restrictions on, or discovery of, the corresponding neutral Higgs bosons if they have relatively low masses and enhanced couplings. Finally, in Part III, the three generation phase invariant measure of CP violation is shown to satisfy a simple and solvable renormalization group equation. Its value falls by four to eight orders of magnitude between the weak and grand unification scales in the standard model, as well as in its two Higgs and supersymmetric extensions. Such a small value of CP violation at the grand unification scale can pose a problem for baryogenesis; this avoided if there are heavy quarks with masses close to their fixed points

New Developments in Supersymmetry (1/5)

CERN Multimedia

CERN. Geneva

2001-01-01

Introduction to supersymmetric grand unified theories. An introduction to the MSSM and different mechanisms for supersymmetry breaking. Then the details of SU(5) and SO(10) unification, the new gauge sector beyond the standard model, representations of quarks and leptons. Gauge and Yukawa coupling unification and some predictions.

New Developments in Supersymmetry (2/5)

CERN Multimedia

CERN. Geneva

2001-01-01

Introduction to supersymmetric grand unified theories. An introduction to the MSSM and different mechanisms for supersymmetry breaking. Then the details of SU(5) and SO(10) unification, the new gauge sector beyond the standard model, representations of quarks and leptons. Gauge and Yukawa coupling unification and some predictions.

New Developments in Supersymmetry (5/5)

CERN Multimedia

CERN. Geneva

2001-01-01

Introduction to supersymmetric grand unified theories. An introduction to the MSSM and different mechanisms for supersymmetry breaking. Then the details of SU(5) and SO(10) unification, the new gauge sector beyond the standard model, representations of quarks and leptons. Gauge and Yukawa coupling unification and some predictions.

New Developments in Supersymmetry (3/5)

CERN Multimedia

CERN. Geneva

2001-01-01

Introduction to supersymmetric grand unified theories. An introduction to the MSSM and different mechanisms for supersymmetry breaking. Then the details of SU(5) and SO(10) unification, the new gauge sector beyond the standard model, representations of quarks and leptons. Gauge and Yukawa coupling unification and some predictions.

Squark and slepton mass relations in grand unified theories

International Nuclear Information System (INIS)

Cheng, H.; Hall, L.J.

1995-01-01

In the minimal supersymmetric standard model, assuming universal scalar masses at large energies, there are four intragenerational relations between the masses of the squarks and sleptons for each light generation. In this paper we study the scalar mass relations which follow only from the assumption that at large energies there is a grand unified theory which leads to a significant prediction of the weak mixing angle. Two new intragenerational mass relations for each of the light generations are derived. In addition, a third mass relation is found which relates the Higgs boson masses, the masses of the third generation scalars, and the masses of the scalars of the lighter generations. Verification of a fourth mass relation, involving only the charged slepton masses, provides a signal for SO(10) unification

Grand unification in higher dimensions with split supersymmetry

International Nuclear Information System (INIS)

Schuster, Philip C.

2006-01-01

We investigate gauge coupling unification in higher dimensional GUT models with split supersymmetry. We focus on 5d and 6d orbifold GUTs, which permit a simple solution to several problems of 4D GUTs as well as control over GUT scale threshold corrections. In orbifold GUTs, calculable threshold corrections can raise or lower the prediction for α s (M Z ) in a way that depends on the location of Higgs fields. On the other hand, split supersymmetry lowers the prediction for α s (M Z ). Consequently, split supersymmetry changes the preferred location of the Higgs fields in orbifold GUTs. In the simplest models, we find that gauge coupling unification favors higgs doublets that live on the orbifold fixed points instead of in the bulk. In addition, relatively high scales of supersymmetry breaking of 10 10±2 GeV are generically favored

N=2 extended supersymmetric GUTs

International Nuclear Information System (INIS)

Fayet, P.

1984-01-01

We construct N = 2 extended SUSY GUTs which provide a general association between massive spin-1 gauge bosons, spin-1/2 inos and spin-0 Higgs bosons. The corresponding gauge hypermultiplets are of four different types, while leptons and quarks are associated with mirror and spin-0 partners. The anticommutators of the two supersymmetry generators provide two spin-0 symmetry generators Zsub(s) and Zsub(p), which do not commute. Their field-independent parts and do commute, however, and appear as central charges in the symmetry algebra of the spontaneously broken gauge theory. These central charges and are linear combinations of global symmetry generators with grand unification generators such as the weak hypercharge (but not the electrical charge). They survive the electroweak symmetry breaking. They do not vanish for massive gauge hypermultiplets of types II and III, which verify M 2 = 2 + 2 > 0 and M 2 > 2 + 2 > 0, respectively. The formula M 2 approx.= 2 + 2 determines the mass spectrum on the grand unification scale, up to electroweak corrections. Finally, we indicate how our mass relations can be interpreted in a 5- or 6-dimensional formalism, the central charges appearing as the extra components of the covariant momentum along the compact fifth or sixth dimensions; and how to evaluate the grand unification mass msub(x) in terms of the lengths of the latter (msub(x)approx.=(h/2π)/Lsub(5(6))c). (orig./HSI)

A minimal supersymmetric model of particle physics and the early universe

International Nuclear Information System (INIS)

Buchmueller, W.; Domcke, V.; Kamada, K.; Schmitz, K.

2013-11-01

We consider a minimal supersymmetric extension of the Standard Model, with right-handed neutrinos and local B-L, the difference between baryon and lepton number, a symmetry which is spontaneously broken at the scale of grand unification. To a large extent, the parameters of the model are determined by gauge and Yukawa couplings of quarks and leptons. We show that this minimal model can successfully account for the earliest phases of the cosmological evolution: Inflation is driven by the energy density of a false vacuum of unbroken B-L symmetry, which ends in tachyonic preheating, i.e. the decay of the false vacuum, followed by a matter dominated phase with heavy B-L Higgs bosons. Nonthermal and thermal processes produce an abundance of heavy neutrinos whose decays generate primordial entropy, baryon asymmetry via leptogenesis and dark matter consisting of gravitinos or nonthermal WIMPs. The model predicts relations between neutrino and superparticle masses and a characteristic spectrum of gravitational waves.

A minimal supersymmetric model of particle physics and the early universe

Energy Technology Data Exchange (ETDEWEB)

Buchmueller, W.; Domcke, V.; Kamada, K. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Schmitz, K. [Tokyo Univ., Kashiwa (Japan). Kavli IPMU, TODIAS

2013-11-15

We consider a minimal supersymmetric extension of the Standard Model, with right-handed neutrinos and local B-L, the difference between baryon and lepton number, a symmetry which is spontaneously broken at the scale of grand unification. To a large extent, the parameters of the model are determined by gauge and Yukawa couplings of quarks and leptons. We show that this minimal model can successfully account for the earliest phases of the cosmological evolution: Inflation is driven by the energy density of a false vacuum of unbroken B-L symmetry, which ends in tachyonic preheating, i.e. the decay of the false vacuum, followed by a matter dominated phase with heavy B-L Higgs bosons. Nonthermal and thermal processes produce an abundance of heavy neutrinos whose decays generate primordial entropy, baryon asymmetry via leptogenesis and dark matter consisting of gravitinos or nonthermal WIMPs. The model predicts relations between neutrino and superparticle masses and a characteristic spectrum of gravitational waves.

A Minimal Supersymmetric Model of Particle Physics and the Early Universe

CERN Document Server

Buchmüller, W; Kamada, K; Schmitz, K

2014-01-01

We consider a minimal supersymmetric extension of the Standard Model, with right-handed neutrinos and local $B$$-$$L$, the difference between baryon and lepton number, a symmetry which is spontaneously broken at the scale of grand unification. To a large extent, the parameters of the model are determined by gauge and Yukawa couplings of quarks and leptons. We show that this minimal model can successfully account for the earliest phases of the cosmological evolution: Inflation is driven by the energy density of a false vacuum of unbroken $B$$-$$L$ symmetry, which ends in tachyonic preheating, i.e.\\ the decay of the false vacuum, followed by a matter dominated phase with heavy $B$$-$$L$ Higgs bosons. Nonthermal and thermal processes produce an abundance of heavy neutrinos whose decays generate primordial entropy, baryon asymmetry via leptogenesis and dark matter consisting of gravitinos or nonthermal WIMPs. The model predicts relations between neutrino and superparticle masses and a characteristic spectrum of g...

Phase transitions at finite chemical potential in grand unified theories

International Nuclear Information System (INIS)

Bailin, D.; Love, A.

1984-01-01

We discuss the circumstances in which non-zero chemical potentials might prevent symmetry restoration in phase transitions in the early universe at grand unification or partial unification scales. The general arguments are illustrated by consideration of SO(10) and SU(5) grand unified theories. (orig.)

SO(10) - Grand unification and fermion masses

International Nuclear Information System (INIS)

Oezer, A.D.

2005-01-01

In this work, we study SO(10) grand unification in its full extent by using different explicit matrix representations which exhibit the structure of SO(10) in a very transparent way. Our approach consists mainly of two stages: We derive the explicit expressions of the mass-eigenvalues and mass-eigenstates of the physical gauge bosons from a mass squared-matrix that contains all the information about the mixing parameters among the gauge fields and the phases which are sources for CP violation. In the light of this analysis, we derive the explicit expressions for the interaction Lagrangians of the charged currents, the neutral currents and the charged and colored currents in SO(10). We present explicit expressions of the vector and axial-vector couplings of the two neutral currents in SO(10). We show how the baryon, lepton and baryon minus lepton number violating processes and their explicit CP violating phases are accommodated in the SO(10) theory. The Higgs potential that we use to implement in the Higgs mechanism is constructed in a most general fashion through a careful study of the Higgs fields of SO(10), where we give special emphasis on illustrating the explicit matrix representation of these Higgs fields. The potential part of the Higgs Lagrangian will give us the properties of the minimum of the vacuum, and the kinetic part will give us the mass-squared matrix of the gauge bosons via spontaneous symmetry breakdown. The same Higgs multiplets will be coupled to fermions through a democratic Yukawa matrix. Thereby, we derive explicit expressions for the fermion masses of the third family including Majorana and Dirac masses for neutrinos. We introduce a flavor-eigenbasis for neutrinos and find the mass-eigenstates and mass-eigenvalues of the neutrinos. Explicit expressions for CP violation in the neutrino sector are obtained. In the second stage of our work, we evaluate all the above mentioned quantities. In addition, we present the values of the physical

Supersymmetric SU(11), the invisible axion, and proton decay

International Nuclear Information System (INIS)

Alwis, S.P. de; Kim, J.E.

1981-09-01

We supersymmetrize the very attractive flavour unification model SU(11). As with other supersymmetric GUTs the gauge hierarchy problem is simplified, but we may also have observable (tausub(p) is approximately 10 33 yrs) proton decay. The required split multiplets are obtained by making the adjoint take a particular direction. Supersymmetry is broken softly at the TeV scale. There is a unique U(1)sub(A) symmetry, and hence there are no true Nambu-Goldstone bosons. The U(1)sub(A) is broken at the GUT scale and there result an invisible axion and neutrino masses. (author)

Unification and new particles at the LHC

Energy Technology Data Exchange (ETDEWEB)

Arkani-Hamed, Nima; D’Agnolo, Raffaele Tito; Low, Matthew [School of Natural Sciences, Institute for Advanced Study,Einstein Drive, Princeton, NJ 08540 (United States); Pinner, David [Princeton Center for Theoretical Physics, Princeton University,Jadwin Hall, Princeton, NJ 08544 (United States)

2016-11-14

Precision gauge coupling unification is one of the primary quantitative successes of low energy or split supersymmetry. Preserving this success puts severe restrictions on possible matter and gauge sectors that might appear at collider-accessible energies. In this work we enumerate new gauge sectors which are compatible with unification, consisting of horizontal gauge groups acting on vector-like matter charged under the Standard Model. Interestingly, almost all of these theories are in the supersymmetric conformal window at high energies and confine quickly after the superpartners are decoupled. For a range of scalar masses compatible with both moderately tuned and minimally split supersymmetry, the confining dynamics happen at the multi-TeV scale, leading to a spectrum of multiple spin-0 and spin-1 resonances accessible to the LHC, with unusual quantum numbers and striking decay patterns.

Unification and new particles at the LHC

International Nuclear Information System (INIS)

Arkani-Hamed, Nima; D’Agnolo, Raffaele Tito; Low, Matthew; Pinner, David

2016-01-01

Precision gauge coupling unification is one of the primary quantitative successes of low energy or split supersymmetry. Preserving this success puts severe restrictions on possible matter and gauge sectors that might appear at collider-accessible energies. In this work we enumerate new gauge sectors which are compatible with unification, consisting of horizontal gauge groups acting on vector-like matter charged under the Standard Model. Interestingly, almost all of these theories are in the supersymmetric conformal window at high energies and confine quickly after the superpartners are decoupled. For a range of scalar masses compatible with both moderately tuned and minimally split supersymmetry, the confining dynamics happen at the multi-TeV scale, leading to a spectrum of multiple spin-0 and spin-1 resonances accessible to the LHC, with unusual quantum numbers and striking decay patterns.

Elementary particles and physics interaction unification

International Nuclear Information System (INIS)

Leite-Lopes, J.

1985-01-01

Quantum theory and relativity theory are fundamental of relativistic quantum mechanics, quantum field theory, which is the base of elementary particle physics, gauge field theory and basic force unification models. After a short introduction of relativistic equations of the main fields, the free scalar field, the free vector field, the free electromagnetic field and the free spinor field, and of elementary particles and basic interactions, gauge invariance and electromagnetic gauge field are detailed. Then the presentation of internal degrees of freedom, especially isospin, introduces gauge field theory of Yang-Mills. At last weak interactions and strong interactions are presented and lead to grand unification theory in conclusion [fr

Topics in supersymmetric theories

International Nuclear Information System (INIS)

Nemeschansky, D.D.

1984-01-01

This thesis discusses four different topics in supersymmetric theories. In the first part models in which supersymmetry is broken by the Fayet-Iliopoulos mechanism are considered. The possibility that scalar quark and lepton masses might arise radiatively in such theories is explored. In the second part supersymmetric grand unified models with a sliding singlet are considered. The author reviews the argument that the sliding singlet does not work in models with large supersymmetry breaking. Then he considers the possibility of using a sliding singlet with low energy supersymmetry breaking. The third part of the thesis deals with the entropy problem of supersymmetric theories. Most supersymmetric models possess a decoupled particle with mass of order 100 GeV which is copiously produced in the early universe and whose decay produces huge amounts of entropy. The author shows how this problem can be avoided in theories in which the hidden sector contains several light fields. In the fourth part effective Lagrangians for supersymmetric theories are studied. The anomalous pion interaction for supersymmetric theories is written down. General properties of this term are studied both on compact and non-compact manifolds

Localized fermions on domain walls and extended supersymmetric quantum mechanics

International Nuclear Information System (INIS)

Oikonomou, V K

2014-01-01

We study fermionic fields localized on topologically unstable domain walls bounded by strings in a grand unified theory theoretical framework. Particularly, we found that the localized fermionic degrees of freedom, which are up and down-quarks as well as charged leptons, are connected to three independent N = 2, d = 1 supersymmetric quantum mechanics algebras. As we demonstrate, these algebras can be combined to form higher order representations of N = 2, d = 1 supersymmetry. Due to the uniform coupling of the domain wall solutions to the down-quarks and leptons, we also show that a higher order N = 2, d = 1 representation of the down-quark–lepton system is invariant under a duality transformation between the couplings. In addition, the two N = 2, d = 1 supersymmetries of the down-quark–lepton system, combine at the coupling unification scale to form an N = 4, d = 1 supersymmetry. Furthermore, we present the various extra geometric and algebraic attributes that the fermionic systems acquire, owing to the underlying N = 2, d = 1 algebras. (paper)

Reduced modular symmetries of threshold corrections and gauge coupling unification

Energy Technology Data Exchange (ETDEWEB)

Bailin, David; Love, Alex [Department of Physics & Astronomy, University of Sussex,Brighton, BN1 9QH (United Kingdom)

2015-04-01

We revisit the question of gauge coupling unification at the string scale in orbifold compactifications of the heterotic string for the supersymmetric Standard Model. In the presence of discrete Wilson lines threshold corrections with modular symmetry that is a subgroup of the full modular group arise. We find that reduced modular symmetries not previously reported are possible. We conjecture that the effects of such threshold corrections can be simulated using sums of terms built from Dedekind eta functions to obtain the appropriate modular symmetry. For the cases of the ℤ{sub 8}-I orbifold and the ℤ{sub 3}×ℤ{sub 6} orbifold it is easily possible to obtain gauge coupling unification at the “observed” scale with Kähler moduli T of approximately one.

Introduction to quantum field theory

International Nuclear Information System (INIS)

Kazakov, D.I.

1988-01-01

The lectures appear to be a continuation to the introduction to elementary principles of the quantum field theory. The work is aimed at constructing the formalism of standard particle interaction model. Efforts are made to exceed the limits of the standard model in the quantum field theory context. Grand unification models including strong and electrical weak interactions, supersymmetric generalizations of the standard model and grand unification theories and, finally, supergravitation theories including gravitation interaction to the universal scheme, are considered. 3 refs.; 19 figs.; 2 tabs

Towards a new paradigm for quark-lepton unification

Energy Technology Data Exchange (ETDEWEB)

Smith, Christopher [Laboratoire de Physique Subatomique et de Cosmologie, Université Grenoble-Alpes, CNRS/IN2P3,53 avenue des Martyrs, 38026 Grenoble Cedex (France)

2017-05-03

The quark and charged lepton mass patterns upset their naïve unification. In this paper, a new approach to solve this problem is proposed. Model-independently, we find that a successful unification can be achieved. A mechanism is identified by which the large top quark mass renders its third-generation leptonic partner very light. This state is thus identified with the electron. We then construct a toy model to implement dynamically this mechanism, using tree-level exchanges of vector leptons to relate the quark and charged lepton flavor structures. In a supersymmetric context, this same mechanism splits the squark masses, and third generation squarks end up much lighter than the others. Finally, the implementation of this mechanism in SU(5) GUT permits to avoid introducing any flavor structure beyond the two minimal Yukawa couplings, ensuring the absence of unknown mixing matrices and their potentially large impact on FCNC.

A constrained supersymmetric left-right model

Energy Technology Data Exchange (ETDEWEB)

Hirsch, Martin [AHEP Group, Instituto de Física Corpuscular - C.S.I.C./Universitat de València, Edificio de Institutos de Paterna, Apartado 22085, E-46071 València (Spain); Krauss, Manuel E. [Bethe Center for Theoretical Physics & Physikalisches Institut der Universität Bonn, Nussallee 12, 53115 Bonn (Germany); Institut für Theoretische Physik und Astronomie, Universität Würzburg,Emil-Hilb-Weg 22, 97074 Wuerzburg (Germany); Opferkuch, Toby [Bethe Center for Theoretical Physics & Physikalisches Institut der Universität Bonn, Nussallee 12, 53115 Bonn (Germany); Porod, Werner [Institut für Theoretische Physik und Astronomie, Universität Würzburg,Emil-Hilb-Weg 22, 97074 Wuerzburg (Germany); Staub, Florian [Theory Division, CERN,1211 Geneva 23 (Switzerland)

2016-03-02

We present a supersymmetric left-right model which predicts gauge coupling unification close to the string scale and extra vector bosons at the TeV scale. The subtleties in constructing a model which is in agreement with the measured quark masses and mixing for such a low left-right breaking scale are discussed. It is shown that in the constrained version of this model radiative breaking of the gauge symmetries is possible and a SM-like Higgs is obtained. Additional CP-even scalars of a similar mass or even much lighter are possible. The expected mass hierarchies for the supersymmetric states differ clearly from those of the constrained MSSM. In particular, the lightest down-type squark, which is a mixture of the sbottom and extra vector-like states, is always lighter than the stop. We also comment on the model’s capability to explain current anomalies observed at the LHC.

Supersymmetry: Theory

International Nuclear Information System (INIS)

Peskin, M.E.

1996-03-01

If supersymmetric particles are discovered at high-energy colliders, what can one hope to learn about them? In principle, the properties of supersymmetric particles can give a window into the physics of grand unification, or of other aspects of interactions at very short distances. In this article, the author sketches out a systematic program for the experimental study of supersymmetric particles and point out the essential role that e + e - linear colliders will play in this investigation

A supersymmetric grand unified theory of flavour with PSL2(7)xSO(10)

International Nuclear Information System (INIS)

King, Stephen F.; Luhn, Christoph

2010-01-01

We construct a realistic Supersymmetric Grand Unified Theory of Flavour based on PSL 2 (7)xSO(10), where the quarks and leptons in the 16 of SO(10) are assigned to the complex triplet representation of PSL 2 (7), while the flavons are assigned to a combination of sextets and anti-triplets of PSL 2 (7). Using a D-term vacuum alignment mechanism, we require the flavon sextets of PSL 2 (7) to be aligned along the 3-3 direction leading to the third family Yukawa couplings, while the flavon anti-triplets describe the remaining Yukawa couplings. Other sextets are aligned along the neutrino flavour symmetry preserving directions leading to tri-bimaximal neutrino mixing via a type II see-saw mechanism, with predictions for neutrinoless double beta decay and cosmology.

Search for Higgs bosons and for Supersymmetric particles at particle collider experiments

CERN Document Server

Muanza, Steve

The corner stone of the Standard Model (SM) of Particle Physics is the Higgs mechanism. It explains how the bosons W, Z and H acquire a mass via weak interactions. In addition it explains how the charged fermions also acquire a mass through Yukawa interactions. And on top of this, it regularizes the scattering of longitudinal W and Z bosons at high energy. The discovery of a Higgs boson by the ATLAS and the CMS collaborations in 2012 marked the culminating success of the SM at explaining most of the known phenomena. However a few other phenomena such as the Dark Matter and the Dark energy cannot be explained by the SM particles. What's more, the SM leaves several open questions such as a quest for a quantum theory for gravity, the naturalness in the Higgs sector, a possible Grand Unification,... The common thread in topics presented in this habilitation thesis is the search for manifestations of a TeV scale supersymmetric (SUSY) extension of the Standard Model at particle collider experiments. Among the predi...

Superunification

International Nuclear Information System (INIS)

Ellis, J.; Zumino, B.; Gaillard, M.K.

1981-09-01

We explore scenarios for exploiting supersymmetry in unified field theories. Supersymmetry must be broken at some level, and we discuss theories with different supergaps. In particular we review the possibility that the hierarchy problem may be alleviated in simply supersymmetric grand unified theories, thanks to certain non-renormalization theorems. Supersymmetric grand unified theories are not truly unified since the supersymmetry generators do not carry internal quantum numbers and gravity is not included. We therefore favour unification in extended supergravity theories, and analize possible schemes of this type, including the possibility that one supersymmetry is retained down to low energies in the form of a supersymmetric GUT. A major problem of unification in extended supergravity theories is the disposal of unwanted helicity states, and we propose some new ideas for achieving this. Our favoured approach postulates the existence in the physical spectrum of infinite-dimensional unitary representations of the noncompact symmetry groups of extended supergravities. Such representations could enable the unwanted helicity states to be paired off, leaving a desirable spectrum of states with masses much less than the Planck mass

A low αs and its consequences for unified model building

International Nuclear Information System (INIS)

Brahmachari, B.; Mohapatra, R.N.

1995-08-01

We review various ways of obtaining consistency between the idea of supersymmetric grand unification and an apparent low value of α s ∼ 0.112 indicated by several low energy experiments. We argue that to reconcile the low value of α s with the predictions of supersymmetric GUTs, we need to go beyond the standard minimal supersymmetric GUT scenario and invoke new physics either at 10 11 - 10 12 GeV, or at the GUT scale. (author). 35 refs, 3 figs, 4 tabs

Physics beyond the standard model in the non-perturbative unification scheme

International Nuclear Information System (INIS)

Kapetanakis, D.; Zoupanos, G.

1990-01-01

The non-perturbative unification scenario predicts reasonably well the low energy gauge couplings of the standard model. Agreement with the measured low energy couplings is obtained by assuming certain kind of physics beyond the standard model. A number of possibilities for physics beyond the standard model is examined. The best candidates so far are the standard model with eight fermionic families and a similar number of Higgs doublets, and the supersymmetric standard model with five families. (author)

Supersymmetric standard model from the heterotic string (II)

International Nuclear Information System (INIS)

Buchmueller, W.; Hamaguchi, K.; Tokyo Univ.; Lebedev, O.; Ratz, M.

2006-06-01

We describe in detail a Z 6 orbifold compactification of the heterotic E 8 x E 8 string which leads to the (supersymmetric) standard model gauge group and matter content. The quarks and leptons appear as three 16-plets of SO(10), two of which are localized at fixed points with local SO(10) symmetry. The model has supersymmetric vacua without exotics at low energies and is consistent with gauge coupling unification. Supersymmetry can be broken via gaugino condensation in the hidden sector. The model has large vacuum degeneracy. Certain vacua with approximate B-L symmetry have attractive phenomenological features. The top quark Yukawa coupling arises from gauge interactions and is of the order of the gauge couplings. The other Yukawa couplings are suppressed by powers of standard model singlet fields, similarly to the Froggatt-Nielsen mechanism. (Orig.)

Impact of the muon anomalous magnetic moment on supersymmetric models

International Nuclear Information System (INIS)

Baer, Howard; Balazs, Csaba; Ferrandis, Javier; Tata, Xerxes

2001-01-01

The recent measurement of a μ =(g μ -2)/2 by the E821 Collaboration at Brookhaven deviates from the quoted standard model (SM) central value prediction by 2.6σ. The difference between SM theory and experiment may be easily accounted for in a variety of particle physics models employing weak scale supersymmetry (SUSY). Other supersymmetric models are distinctly disfavored. We evaluate a μ for various supersymmetric models, including minimal supergravity, Yukawa unified SO(10) SUSY GUT's, models with inverted mass hierarchies, models with nonuniversal gaugino masses, gauge mediated SUSY breaking models, anomaly-mediated SUSY breaking models and models with gaugino mediated SUSY breaking. Models with Yukawa coupling unification or multi-TeV first and second generation scalars are disfavored by the a μ measurement

ACADEMIC TRAINING LECTURE

CERN Multimedia

Academic Training; Tel. 73127

2001-01-01

2, 3, 4, 5 and 6 April REGULAR LECTURE PROGRAMME From 11:00 hrs - Main Auditorium bldg. 500 New Developments in Supersymmetry S. Raby / CERN-TH Introduction to supersymmetric grand unified theories. An introduction to the MSSM and different mechanisms for supersymmetry breaking. Then the details of SU(5) and SO(10) unification, the new gauge sector beyond the standard model, representations of quarks and leptons. Gauge and Yukawa coupling unification and some predictions.

All possible lightest supersymmetric particles in proton hexality violating minimal supergravity models and their signals at hadron colliders

International Nuclear Information System (INIS)

Grab, Sebastian

2009-08-01

The most widely studied supersymmetric scenario is the minimal supersymmetric standard model (MSSM) with more than a hundred free parameters. However for detailed phenomenological studies, the minimal supergravity (mSUGRA) model, a restricted and well-motivated framework for the MSSM, is more convenient. In this model, lepton- and baryon-number violating interactions are suppressed by a discrete symmetry, R-parity or proton-hexality, to keep the proton stable. However, it is sufficient to forbid only lepton- or baryon-number violation. We thus extend mSUGRA models by adding a proton-hexality violating operator at the grand unification scale. This can change the supersymmetric spectrum leading on the one hand to a sneutrino, smuon or squark as the lightest supersymmetric particle (LSP). On the other hand, a wide parameter region is reopened, where the scalar tau (stau) is the LSP. We investigate in detail the conditions leading to non-neutralino LSP scenarios. We take into account the restrictions from neutrino masses, the muon anomalous magnetic moment, b→sγ, and other precision measurements. We furthermore investigate existing restrictions from direct searches at LEP, the Tevatron, and the CERN p anti p collider. It is vital to know the nature of the LSP, since supersymmetric particles normally cascade decay down to the LSP at collider experiments. We present typical LHC signatures for sneutrino LSP scenarios. Promising signatures are high-p T muons and jets, like-sign muon events and detached vertices from long lived taus. We also classify the stau LSP decays and describe their dependence on the mSUGRA parameters. We then exploit our results for resonant single slepton production at the LHC. We find novel signatures with like-sign muon and three- and four-muon final states. Finally, we perform a detailed analysis for single slepton production in association with a single top quark. We show that the signal can be distinguished from the background at the LHC

All possible lightes supersymmetric particles in proton hexality violating minimal supergravity models and their signals at hadron colliders

Energy Technology Data Exchange (ETDEWEB)

Grab, Sebastian

2009-08-15

The most widely studied supersymmetric scenario is the minimal supersymmetric standard model (MSSM) with more than a hundred free parameters. However for detailed phenomenological studies, the minimal supergravity (mSUGRA) model, a restricted and well-motivated framework for the MSSM, is more convenient. In this model, lepton- and baryon-number violating interactions are suppressed by a discrete symmetry, R-parity or proton-hexality, to keep the proton stable. However, it is sufficient to forbid only lepton- or baryon-number violation. We thus extend mSUGRA models by adding a proton-hexality violating operator at the grand unification scale. This can change the supersymmetric spectrum leading on the one hand to a sneutrino, smuon or squark as the lightest supersymmetric particle (LSP). On the other hand, a wide parameter region is reopened, where the scalar tau (stau) is the LSP. We investigate in detail the conditions leading to non-neutralino LSP scenarios. We take into account the restrictions from neutrino masses, the muon anomalous magnetic moment, b{yields}s{gamma}, and other precision measurements. We furthermore investigate existing restrictions from direct searches at LEP, the Tevatron, and the CERN p anti p collider. It is vital to know the nature of the LSP, since supersymmetric particles normally cascade decay down to the LSP at collider experiments. We present typical LHC signatures for sneutrino LSP scenarios. Promising signatures are high-p{sub T} muons and jets, like-sign muon events and detached vertices from long lived taus. We also classify the stau LSP decays and describe their dependence on the mSUGRA parameters. We then exploit our results for resonant single slepton production at the LHC. We find novel signatures with like-sign muon and three- and four-muon final states. Finally, we perform a detailed analysis for single slepton production in association with a single top quark. We show that the signal can be distinguished from the background

Patterns of flavor signals in supersymmetric models

Energy Technology Data Exchange (ETDEWEB)

Goto, T. [KEK National High Energy Physics, Tsukuba (Japan)]|[Kyoto Univ. (Japan). YITP; Okada, Y. [KEK National High Energy Physics, Tsukuba (Japan)]|[Graduate Univ. for Advanced Studies, Tsukuba (Japan). Dept. of Particle and Nucelar Physics; Shindou, T. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)]|[International School for Advanced Studies, Trieste (Italy); Tanaka, M. [Osaka Univ., Toyonaka (Japan). Dept. of Physics

2007-11-15

Quark and lepton flavor signals are studied in four supersymmetric models, namely the minimal supergravity model, the minimal supersymmetric standard model with right-handed neutrinos, SU(5) supersymmetric grand unified theory with right-handed neutrinos and the minimal supersymmetric standard model with U(2) flavor symmetry. We calculate b{yields}s(d) transition observables in B{sub d} and B{sub s} decays, taking the constraint from the B{sub s}- anti B{sub s} mixing recently observed at Tevatron into account. We also calculate lepton flavor violating processes {mu} {yields} e{gamma}, {tau} {yields} {mu}{gamma} and {tau} {yields} e{gamma} for the models with right-handed neutrinos. We investigate possibilities to distinguish the flavor structure of the supersymmetry breaking sector with use of patterns of various flavor signals which are expected to be measured in experiments such as MEG, LHCb and a future Super B Factory. (orig.)

Patterns of flavor signals in supersymmetric models

International Nuclear Information System (INIS)

Goto, T.; Tanaka, M.

2007-11-01

Quark and lepton flavor signals are studied in four supersymmetric models, namely the minimal supergravity model, the minimal supersymmetric standard model with right-handed neutrinos, SU(5) supersymmetric grand unified theory with right-handed neutrinos and the minimal supersymmetric standard model with U(2) flavor symmetry. We calculate b→s(d) transition observables in B d and B s decays, taking the constraint from the B s - anti B s mixing recently observed at Tevatron into account. We also calculate lepton flavor violating processes μ → eγ, τ → μγ and τ → eγ for the models with right-handed neutrinos. We investigate possibilities to distinguish the flavor structure of the supersymmetry breaking sector with use of patterns of various flavor signals which are expected to be measured in experiments such as MEG, LHCb and a future Super B Factory. (orig.)

A new flavour imprint of SU(5-like grand unification and its LHC signatures

Directory of Open Access Journals (Sweden)

S. Fichet

2015-03-01

Full Text Available We point out that the hypothesis of an SU(5-like supersymmetric Grand Unified Theory (GUT implies a generic relation within the flavour structure of up-type squarks. Contrary to other well-known SU(5 relations between the down-quark and charged lepton sectors, this relation remains exact in the presence of any corrections and extra operators. Moreover it remains valid to a good precision at the electroweak scale, and opens thus new possibilities for testing SU(5-like GUTs. We derive the low-energy effective theory of observable light up-type squarks, that also constitutes a useful tool for squark phenomenology. We use this effective theory to determine how to test SU(5 relations at the LHC. Focusing on scenarios with light stops, compatible with Natural SUSY, it appears that simple tests involving ratios of event rates are sufficient to test the hypothesis of an SU(5-like GUT theory. The techniques of charm-tagging and top-polarimetry are a crucial ingredient of these tests.

Beyond the CMSSM without an Accelerator: Proton Decay and Direct Dark Matter Detection

CERN Document Server

Ellis, John; Luo, Feng; Nagata, Natsumi; Olive, Keith A; Sandick, Pearl

2016-01-01

We consider two potential non-accelerator signatures of generalizations of the well-studied constrained minimal supersymmetric standard model (CMSSM). In one generalization, the universality constraints on soft supersymmetry-breaking parameters are applied at some input scale $M_{in}$ below the grand unification (GUT) scale $M_{GUT}$, a scenario referred to as `sub-GUT'. The other generalization we consider is to retain GUT-scale universality for the squark and slepton masses, but to relax universality for the soft supersymmetry-breaking contributions to the masses of the Higgs doublets. As with other CMSSM-like models, the measured Higgs mass requires supersymmetric particle masses near or beyond the TeV scale. Because of these rather heavy sparticle masses, the embedding of these CMSSM-like models in a minimal SU(5) model of grand unification can yield a proton lifetime consistent with current experimental limits, and may be accessible in existing and future proton decay experiments. Another possible signat...

DESY: Theory Workshop 1994

International Nuclear Information System (INIS)

Anon.

1995-01-01

For 1994, the traditional annual DESY Theory Workshop was devoted to supersymmetry. This is a novel symmetry relating bosons (normally force-carrying particles) and fermions (which normally feel the forces). In supersymmetry, bosons could have fermion counterparts, and vice versa. Although this subject is still largely a theorist's playground, many of the particles and phenomena predicted by models of low energy supersymmetry now seem within reach of present and planned future accelerator experiments, and this was one of the main reasons for choosing a more speculative theme after more phenomenological orientations in recent DESY Theory Workshops. After the welcome by DESY Director General Bjorn Wiik, attention was immediately focused on experimental aspects. P. Steffen (DESY) presented the latest results from HERA. In the following talks, K. Honscheid (Ohio), S. Lammel (Fermilab) and S. Komamiya (CERN and Tokyo) reviewed the experimental situation at electron-proton, hadron and electron-positron colliders, respectively. They discussed the most recent limits for supersymmetric particles (still none in sight!), as well as precision experiments where deviations from the standard model might show up. The workshop was treated to a first rate introduction to the MSSM (''minimal supersymmetric standard model'') by F. Zwirner (CERN), who clearly explained the motivation for going supersymmetric and reviewed the basic structure of the MSSM, its particle content and couplings, as well as the soft breaking terms necessary to avoid immediate conflict with experiment. This was followed by a systematic discussion of the Higgs sector by H. Haber (Santa Cruz), where the first hints of new physics could appear. However, he also made clear that it may not be easy to distinguish standard and non-standard Higgs bosons. Symmetries beyond the standard model, and in particular supersymmetric grand unification were treated in detail by G. Ross (Oxford) and S

Pramana – Journal of Physics | Indian Academy of Sciences

Indian Academy of Sciences (India)

pp 223-229 Special: Supersymmetric Unified Theories and Higgs Physics. Prospects of experimentally reachable beyond Standard Model physics in inverse see-saw motivated SO(10) GUT · Ram Lal Awasthi · More Details Abstract Fulltext PDF. The grand unification theories based on SO(10) gauge group have been at the ...

Light grand unified theory triplets and Yukawa splitting

International Nuclear Information System (INIS)

Rakshit, Subhendu; Shadmi, Yael; Raz, Guy; Roy, Sourov

2004-01-01

Triplet-mediated proton decay in grand unified theories (GUTs) is usually suppressed by arranging a large triplet mass. Here we explore instead a mechanism for suppressing the couplings of the triplets to the first and second generations compared to the Yukawa couplings, so that the triplets can be light. This mechanism is based on a 'triplet symmetry' in the context of product-group GUTs. We study two possibilities. The first possibility, which requires the top Yukawa coupling to arise from a nonrenormalizable operator at the GUT scale, is that all triplet couplings to matter are negligible, so that the triplets can be at the weak scale, giving new evidence for grand unification. The second possibility is that some triplet couplings, and in particular Ttb and Tt-barl-bar, are equal to the corresponding Yukawa couplings. This would give a distinct signature of grand unification if the triplets were sufficiently light. However, we derive a model-independent bound on the triplet mass in this case, which is at least 10 6 GeV. Finally, we construct an explicit viable GUT model based on Yukawa splitting, with the triplets at 10 14 GeV, as required for coupling unification to work. This model requires no additional thresholds below the GUT scale

Unification

International Nuclear Information System (INIS)

Iliopoulos, J.

1983-01-01

This chapter describes the weak and electromagnetic interactions by a gauge theory based on the group U(1)xSU(2). Discusses SO(10), E 6 , beyond gauge theories, Grassmann algebras, graded superalgebras, Majorana and Weyl spinors; particle representations; all possible supersymmetries of the S-matrix; representations in terms of fields; a simple field theory model; supersymmetry and gauge invariance; the breaking of supersymmetry; the supersymmetric extension of the standard model; and supersymmetry and grand-unified theories. Finds that the rate of approach to the symmetric, which is logarithmic for dimensionless couplings, is too slow to account for the high accuracy with which symmetries are observed in nature. Shows that scalar Q.E.D. in perturbation theory is not an I.R. attractor when one attempts to approach it via a class of theories with negative metric

Supersymmetric SO(10) models inspired by deconstruction

International Nuclear Information System (INIS)

Huang Chaoshang; Jiang Jing; Li Tianjun

2004-01-01

We consider 4-dimensional N=1 supersymmetric SO(10) models inspired by deconstruction of 5-dimensional N=1 supersymmetric orbifold SO(10) models and high-dimensional non-supersymmetric SO(10) models with Wilson line gauge symmetry breaking. We discuss the SO(10)xSO(10) models with bi-fundamental link fields where the gauge symmetry can be broken down to the Pati-Salam, SU(5)xU(1), flipped SU(5)xU(1)' or the Standard Model like gauge symmetry. We also propose an SO(10)xSO(6)xSO(4) model with bi-fundamental link fields where the gauge symmetry is broken down to the Pati-Salam gauge symmetry, and an SO(10)xSO(10) model with bi-spinor link fields where the gauge symmetry is broken down to the flipped SU(5)xU(1)' gauge symmetry. In these two models, the Pati-Salam and flipped SU(5)xU(1)' gauge symmetry can be further broken down to the Standard Model gauge symmetry, the doublet-triplet splittings can be obtained by the missing partner mechanism, and the proton decay problem can be solved. We also study the gauge coupling unification. We briefly comment on the interesting variation models with gauge groups SO(10)xSO(6) and SO(10)xflippedSU(5)xU(1)' in which the proton decay problem can be solved

e+e- collisions at 500 GeV: The physics potential. Pt. C. Proceedings

International Nuclear Information System (INIS)

Zerwas, P.M.

1993-12-01

These proceedings contain the articles presented at the named workshop. These concern the production of Higgs bosons, electroweak gauge bosons, top particles, particles required by grand unification, supersymmetric particles in 500 Gev e + e - interactions together with γγ physics and some description of collider detectors. See hints under the relevant topics. (HSI)

The Supersymmetric Top-Ten Lists

OpenAIRE

Haber, Howard E.

1993-01-01

Ten reasons are given why supersymmetry is the leading candidate for physics beyond the Standard Model. Ultimately, the experimental discovery of supersymmetric particles at future colliders will determine whether supersymmetry is relevant for TeV scale physics. The grand hope of supersymmetry enthusiasts is to connect TeV scale supersymmetry with Planck scale physics. The ten most pressing theoretical problems standing in the way of this goal are briefly described.

Supersymmetry in Z' decays

International Nuclear Information System (INIS)

Corcella, G.

2014-01-01

I study the phenomenology of new heavy neutral gauge bosons Z', predicted by Grand Unification Theories-driven U(1)' gauge groups and by the sequential standard model. BSM (Beyond Standard Model) decays into supersymmetric final states are accounted for, besides the SM (Standard Model) modes usually investigated. I give an estimate of the number of supersymmetric events in Z' decays possibly expected at LHC, as well as of the product of the Z' cross section times the branching fraction into electron and muon pairs. (author)

Gauge coupling running in minimal SU(3) x SU(2) x U(1) superstring unification

CERN Document Server

Ibáñez, L E; Ross, Graham G

1991-01-01

We study the evolution of the gauge coupling constants in string unification schemes in which the light spectrum below the compactification scale is exactly that of the minimal supersymmetric standard model. In the absence of string threshold corrections the predicted values $\\sin^2\\theta _W=0.218$ and $\\alpha _s=0.20$ are in gross conflict with experiment, but these corrections are generically important. One can express the string threshold corrections to $\\sin^2\\theta _W$ and $\\alpha_s$ in terms of certain $modular$ $weights$ of quark, lepton and Higgs superfields as well as the $moduli$ of the string model. We find that in order to get agreement with the experimental measurements within the context of this $minimal$ scheme, certain constraints on the $modular$ $weights$ of the quark, lepton and Higgs superfields should be obeyed. Our analysis indicates that this $minimal$ $string$ $unification$

Preon Model and Family Replicated E_6 Unification

Directory of Open Access Journals (Sweden)

Larisa V. Laperashvili

2008-02-01

Full Text Available Previously we suggested a new preon model of composite quark-leptons and bosons with the 'flipped' $E_6imes widetilde{E_6}$ gauge symmetry group. We assumed that preons are dyons having both hyper-electric $g$ and hyper-magnetic $ilde g$ charges, and these preons-dyons are confined by hyper-magnetic strings which are an ${f N}=1$ supersymmetric non-Abelian flux tubes created by the condensation of spreons near the Planck scale. In the present paper we show that the existence of the three types of strings with tensions $T_k=k T_0$ $(k = 1,2,3$ producing three (and only three generations of composite quark-leptons, also provides three generations of composite gauge bosons ('hyper-gluons' and, as a consequence, predicts the family replicated $[E_6]^3$ unification at the scale $sim 10^{17}$ GeV. This group of unification has the possibility of breaking to the group of symmetry: $ [SU(3_C]^3imes [SU(2_L]^3imes [U(1_Y]^3 imes [U(1_{(B-L}]^3$ which undergoes the breakdown to the Standard Model at lower energies. Some predictive advantages of the family replicated gauge groups of symmetry are briefly discussed.

The vacuum of the minimal nonsupersymmetric SO(10) unification

International Nuclear Information System (INIS)

Bertolini, Stefano; Di Luzio, Luca; Malinsky, Michal

2010-01-01

We study a class of nonsupersymmetric SO(10) grand-unified scenarios where the first stage of the symmetry breaking is driven by the vacuum expectation values of the 45-dimensional adjoint representation. Three-decade-old results claim that such a Higgs setting may lead exclusively to the flipped SU(5) x U(1) intermediate stage. We show that this conclusion is actually an artifact of the tree-level potential. The study of the accidental global symmetries emerging in various limits of the scalar potential offers a simple understanding of the tree-level result and a rationale for the drastic impact of quantum corrections. We scrutinize in detail the simplest and paradigmatic case of the 45 H +16 H Higgs sector triggering the breaking of SO(10) to the standard electroweak model. We show that the minimization of the one-loop effective potential allows for intermediate SU(4) C x SU(2) L x U(1) R and SU(3) c x SU(2) L x SU(2) R x U(1) B-L symmetric stages as well. These are the options favored by gauge unification. Our results, that apply whenever the SO(10) breaking is triggered by H >, open the path for hunting the simplest realistic scenario of nonsupersymmetric SO(10) grand unification.

Supersymmetric Grand Unification and Lepton Universality in $K \\to l\

CERN Document Server

Ellis, Jonathan Richard; Raidal, Martti

2009-01-01

in the near future, one may nevertheless obtain significant constraints on the model parameters and unknown aspects of right-handed fermion and sfermion mixing. Motivated by the prospects for an improved test of lepton universality in K -> l \

Lepton flavor violation

International Nuclear Information System (INIS)

Cooper, M.D. Brooks, M.; Hogan, G.E.

1997-01-01

The connection of rare decays to supersymmetric grand unification is highlighted, and a review of the status of rare decay experiments is given. Plans for future investigations of processes that violate lepton flavor are discussed. A new result from the MEGA experiment, a search for μ + → e + γ, is reported to be B.R. -11 with 90% confidence

μ+ → e+γ and related rare decays

International Nuclear Information System (INIS)

Cooper, M.D.

1997-01-01

The connection of rare decays to supersymmetric grand unification is highlighted, and a brief review of the status of rare decay experiments is given. The status of the MEGA experiment, a search for μ + → e + γ, is reported. Some ideas for a new experimental arrangement that has the potential to reach a sensitivity of 10 -14 are presented

Aspects of the flipped unification of strong, weak and electromagnetic interactions

Energy Technology Data Exchange (ETDEWEB)

Ellis, J.; Hagelin, J.S.; Kelley, S.; Nanopoulos, D.V.

1988-12-19

We explore phenomenological aspects of a recently proposed flipped SU(5) x U(1) supersymmetric GUT which incorporates an economical and natural mechanism for splitting Higgs doublets and triplets, and can be derived from string theory. Using experimental values of sin/sup 2/theta/sub W/ and the strong QCD coupling, we estimate the grand unification scale M/sub G/, where the strong and weak coupling strengths are equal, and the superunification scale M/sub SU/, where all couplings are equal. We find typical values of M/sub G/ approx. = 10/sup 15/ to 10/sup 17/ GeV, with M/sub SU/ somewhat higher and close to the value suggested by string models. We discuss different mechanisms for baryon decay, finding that the dominant one is gauge-boson exchange giving rise to p -> e/sup +/ /sup 0/, anti /sup +/ and n -> e/sup +/ /sup -/, anti /sup 0/ with partial lifetimes approx. = 10/sup 35+-2/ y. We show that a large GUT symmetry-breaking scale M/sub G/ is naturally generated by radiative corrections to the effective potential if a small amount approx. = m/sub W/ of soft supersymmetry breaking is generated dynamically at a large scale. We analyze the low-energy effective theory obtained using the renormalization group equations, demonstrating that electroweak symmetry breaking is obtained if m/sub t/ approx. = 60 to 90 GeV. We analyze the spectrum of sparticles, with particular attention to neutralinos.

Gauge coupling unification and nonequilibrium thermal dark matter.

Science.gov (United States)

Mambrini, Yann; Olive, Keith A; Quevillon, Jérémie; Zaldívar, Bryan

2013-06-14

We study a new mechanism for the production of dark matter in the Universe which does not rely on thermal equilibrium. Dark matter is populated from the thermal bath subsequent to inflationary reheating via a massive mediator whose mass is above the reheating scale T(RH). To this end, we consider models with an extra U(1) gauge symmetry broken at some intermediate scale (M(int) ≃ 10(10)-10(12) GeV). We show that not only does the model allow for gauge coupling unification (at a higher scale associated with grand unification) but it can provide a dark matter candidate which is a standard model singlet but charged under the extra U(1). The intermediate scale gauge boson(s) which are predicted in several E6/SO(10) constructions can be a natural mediator between dark matter and the thermal bath. We show that the dark matter abundance, while never having achieved thermal equilibrium, is fixed shortly after the reheating epoch by the relation T(RH)(3)/M(int)(4). As a consequence, we show that the unification of gauge couplings which determines M(int) also fixes the reheating temperature, which can be as high as T(RH) ≃ 10(11) GeV.

Supersymmetric interpretations of the neutrino anomalies

CERN Document Server

Valle, José W F

2002-01-01

Solar and atmospheric neutrino data strongly indicate the need for physics beyond the standard model. The neutrino oscillation interpretation of the atmospheric data is rather unambiguous, with more options still open for the solar data. After a brief summary of the latest global fits of neutrino data, I discuss theoretical neutrino mass models. This is done first from a top-bottom approach inspired by unification ideas involving a see-saw mechanism or high dimension operators. Then I consider bottom-up approaches, with especial emphasis on the idea that the origin of neutrino mass and mixing is intrinsically supersymmetric. Models involve effective bilinear breaking of R-parity. This allows for the possibility of probing the neutrino mixing also in the context of high-energy collider experiments such as the LHC. (41 refs).

Inverted hierarchy and asymptotic freedom in grand unified supersymmetric theories

International Nuclear Information System (INIS)

Aratyn, H.

1983-01-01

The interrelation between an inverted hierarchy mechanism and asymptotic freedom in supersymmetric theories is analyzed in two models for which we performed a detailed analysis of the effective potentials and effective couplings. We find it difficult to accommodate an inverted hierarchy together with asymptotic freedom for the matter-Yukawa couplings. (orig.)

Gauge unification in highly anisotropic string compactifications

International Nuclear Information System (INIS)

Hebecker, A.; Trapletti, M.

2005-01-01

It is well known that heterotic string compactifications have, in spite of their conceptual simplicity and aesthetic appeal, a serious problem with precision gauge coupling unification in the perturbative regime of string theory. Using both a duality-based and a field-theoretic definition of the boundary of the perturbative regime, we reevaluate the situation in a quantitative manner. We conclude that the simplest and most promising situations are those where some of the compactification radii are exceptionally large, corresponding to highly anisotropic orbifold models. Thus, one is led to consider constructions which are known to the effective field-theorist as higher-dimensional or orbifold grand unified theories (orbifold GUTs). In particular, if the discrete symmetry used to break the GUT group acts freely, a non-local breaking in the larger compact dimensions can be realized, leading to a precise gauge coupling unification as expected on the basis of the MSSM particle spectrum. Furthermore, a somewhat more model dependent but nevertheless very promising scenario arises if the GUT breaking is restricted to certain singular points within the manifold spanned by the larger compactification radii

The subgroup structure of grand unified theories with application to the fermion mass matrix in 0(10)

International Nuclear Information System (INIS)

Feldman, G.; Fulton, T.

1982-01-01

A technique, using the orthonormal basis for roots and weights of compact Lie groups, introduced by Van der Waerden and developed by Dynkin (Am. Math. Soc. Transl.; 17: (1950) and Sec 2,6:111 (1957)) provides a convenient framework for discussing mass relations in grand unification theories. The structure constants Nsub(αβ) for SU(R + 1), O(2R + 1), Sp(2R), O(2R) and G(2) are obtained in an appendix, using an approach arising from this basis. The method for obtaining generators of non-regular subalgebras, in terms of generators of the original algebras, is discussed in terms of the basis. It is necessary to know this structure in order to trace the history of particles, originally in some grand unification group, through the various chains of decompositions into subgroups. As an illustration, the methods are applied to finding the minimal, non-trivial, mass relations for fermions in the O(10) grand unification scheme. (author)

Supersymmetric moduli stabilization and high-scale inflation

International Nuclear Information System (INIS)

Buchmueller, Wilfried; Wieck, Clemens; Winkler, Martin Wolfgang

2014-04-01

We study the back-reaction of moduli fields on the inflaton potential in generic models of F-term inflation. We derive the moduli corrections as a power series in the ratio of Hubble scale and modulus mass. The general result is illustrated with two examples, hybrid inflation and chaotic inflation. We find that in both cases the decoupling of moduli dynamics and inflation requires moduli masses close to the scale of grand unification. For smaller moduli masses the CMB observables are strongly affected.

The Super-GUT CMSSM Revisited

CERN Document Server

Ellis, John

2016-01-01

We revisit minimal supersymmetric SU(5) grand unification (GUT) models in which the soft supersymmetry-breaking parameters of the minimal supersymmetric Standard Model (MSSM) are universal at some input scale, $M_{in}$, above the supersymmetric gauge coupling unification scale, $M_{GUT}$. As in the constrained MSSM (CMSSM), we assume that the scalar masses and gaugino masses have common values, $m_0$ and $m_{1/2}$ respectively, at $M_{in}$, as do the trilinear soft supersymmetry-breaking parameters $A_0$. Going beyond previous studies of such a super-GUT CMSSM scenario, we explore the constraints imposed by the lower limit on the proton lifetime and the LHC measurement of the Higgs mass, $m_h$. We find regions of $m_0$, $m_{1/2}$, $A_0$ and the parameters of the SU(5) superpotential that are compatible with these and other phenomenological constraints such as the density of cold dark matter, which we assume to be provided by the lightest neutralino. Typically, these allowed regions appear for $m_0$ and $m_{1/...

Signals of doubly-charged Higgsinos at the CERN Large Hadron Collider

International Nuclear Information System (INIS)

Demir, Durmus A.; Frank, Mariana; Turan, Ismail; Huitu, Katri; Rai, Santosh Kumar

2008-01-01

Several supersymmetric models with extended gauge structures, motivated by either grand unification or by neutrino mass generation, predict light doubly-charged Higgsinos. In this work we study productions and decays of doubly-charged Higgsinos present in left-right supersymmetric models, and show that they invariably lead to novel collider signals not found in the minimal supersymmetric model or in any of its extensions motivated by the μ problem or even in extra dimensional theories. We investigate their distinctive signatures at the Large Hadron Collider in both pair- and single-production modes, and show that they are powerful tools in determining the underlying model via the measurements at the Large Hadron Collider experiments.

Grand unification in the heterotic brane world

International Nuclear Information System (INIS)

Vaudrevange, Patrick Karl Simon

2008-08-01

String theory is known to be one of the most promising candidates for a uni ed description of all elementary particles and their interactions. Starting from the ten-dimensional heterotic string, we study its compactification on six-dimensional orbifolds. We clarify some important technical aspects of their construction and introduce new parameters, called generalized discrete torsion. We identify intrinsic new relations between orbifolds with and without (generalized) discrete torsion. Furthermore, we perform a systematic search for MSSM-like models in the context of Z 6 -II orbifolds. Using local GUTs, which naturally appear in the heterotic brane world, we construct about 200 MSSM candidates. We find that intermediate SUSY breaking through hidden sector gaugino condensation is preferred in this set of models. A specific model, the so-called benchmark model, is analyzed in detail addressing questions like the identification of a supersymmetric vacuum with a naturally small μ-term and proton decay. Furthermore, as vevs of twisted fields correspond to a resolution of orbifold singularities, we analyze the resolution of Z 3 singularities in the local and in the compact case. Finally, we exemplify this procedure with the resolution of a Z 3 MSSM candidate. (orig.)

Grand unification in the heterotic brane world

Energy Technology Data Exchange (ETDEWEB)

Vaudrevange, Patrick Karl Simon

2008-08-15

String theory is known to be one of the most promising candidates for a uni ed description of all elementary particles and their interactions. Starting from the ten-dimensional heterotic string, we study its compactification on six-dimensional orbifolds. We clarify some important technical aspects of their construction and introduce new parameters, called generalized discrete torsion. We identify intrinsic new relations between orbifolds with and without (generalized) discrete torsion. Furthermore, we perform a systematic search for MSSM-like models in the context of Z{sub 6}-II orbifolds. Using local GUTs, which naturally appear in the heterotic brane world, we construct about 200 MSSM candidates. We find that intermediate SUSY breaking through hidden sector gaugino condensation is preferred in this set of models. A specific model, the so-called benchmark model, is analyzed in detail addressing questions like the identification of a supersymmetric vacuum with a naturally small {mu}-term and proton decay. Furthermore, as vevs of twisted fields correspond to a resolution of orbifold singularities, we analyze the resolution of Z{sub 3} singularities in the local and in the compact case. Finally, we exemplify this procedure with the resolution of a Z{sub 3} MSSM candidate. (orig.)

Report of the SUGRA Working Group for Run II of the Tevatron

CERN Document Server

Barger, V.; Flattum, E.; Falk, T.; Abel, S.; Accomando, E.; Anderson, G.; Arnowitt, R.; Azzi, P.; Baer, H.; Bagger, J.; Beenakker, W.; Belyaev, A.; Berger, E.; Berger, M.; Brhlik, M.; Blazek, T.; Blessing, S.; Bokhari, W.; Bruner, N.; Carena, M.; Chakraborty, D.; Chang, D.; Chankowski, P.; Chen, C.H.; Cheng, H.C.; Chertok, M.; Cho, G.C.; Claes, D.; Demina, R.; Done, J.; Duflot, L.; Dutta, Bhaskar; Eboli, O.J.P.; Eno, S.; Feng, J.; Ganis, G.; Gold, M.; Gregores, E.M.; Hagiwara, K.; Han, T.; Harris, B.; Hikasa, K.; Holck, C.; Kao, C.; Kato, Y.; Klasen, M.; Keung, W.Y.; Kramer, M.; Lammel, S.; Li, T.J.; Lykken, J.D.; Magro, M.; Mani, S.; Matchev, K.T.; Mangano, M.; Mercadante, P.; Mrenna, S.; Nachtman, J.; Nath, P.; Nojiri, M.M.; Nomerotski, A.; Norman, D.; Oishi, R.; Ono, K.; Paige, F.; Paterno, M.; Parke, S.; Pierce, D.; Pilaftsis, A.; Plehn, T.; Pompos, A.; Polonksy, N.; Pokorski, S.; Quintana, P.; Roco, M.; Saltzberg, D.; Savoy-Navarro, A.; Seiya, Y.; Smith, C.; Spira, M.; Spiropulu, M.; Sullivan, Z.; Szalapski, R.; Tannenbaum, B.; Tait, T.; Wackeroth, D.; Wang, Y.; White, J.; Williams, H.H.; Worcester, M.; Worm, S.; Zhang, R.J.; Zielinski, M.

2000-01-01

We present an analysis of the discovery reach for supersymmetric particles at the upgraded Tevatron collider, assuming that SUSY breaking results in universal soft breaking parameters at the grand unification scale, and that the lightest supersymmetric particle is stable and neutral. We first present a review of the literature, including the issues of unification, renormalization group evolution of the supersymmetry breaking parameters and the effect of radiative corrections on the effective low energy couplings and masses of the theory. We consider the experimental bounds coming from direct searches and those arising indirectly from precision data, cosmology and the requirement of vacuum stability. The issues of flavor and CP-violation are also addressed. The main subject of this study is to update sparticle production cross sections, make improved estimates of backgrounds, delineate the discovery reach in the supergravity framework, and examine how this might vary when assumptions about universality of soft...

Supersymmetry, supergravity, and unification

CERN Document Server

Nath, Pran

2017-01-01

This unique book gives a modern account of particle physics and gravity based on supersymmetry and supergravity, two of the most significant developments in theoretical physics since general relativity. The book begins with a brief overview of the history of unification and then goes into a detailed exposition of both fundamental and phenomenological topics. The topics in fundamental physics include Einstein gravity, Yang-Mills theory, anomalies, the standard model, supersymmetry and supergravity, and the construction of supergravity couplings with matter and gauge fields, as well as computational techniques for SO(10) couplings. The topics of phenomenological interest include implications of supergravity models at colliders, CP violation, and proton stability, as well as topics in cosmology such as inflation, leptogenesis, baryogenesis, and dark matter. The book is intended for graduate students and researchers seeking to master the techniques for building grand unified models.

Towards low energy physics from the heterotic string

Energy Technology Data Exchange (ETDEWEB)

Sanchez, S.N.R.

2008-06-15

We investigate orbifold compactifications of the heterotic string, addressing in detail their construction, classification and phenomenological potential. Based on the insight gained from grand unification theories, we develop a successful strategy to search for models resembling the minimal supersymmetric extension of the standard model (MSSM) in Z{sub 6}-II orbifold compactifications. We find about 200 MSSM candidates with the gauge group and the exact spectrum of the MSSM, and supersymmetric vacua below the compactification scale. Among them, there are several models with the following realistic features: R-parity, seesaw suppressed neutrino masses, and intermediate scale of supersymmetry breakdown. (orig.)

Functional Pearls : Polytypic Unification

NARCIS (Netherlands)

Jansson, P.; Jeuring, J.T.

1998-01-01

Unification, or two-way pattern matching, is the process of solving an equation involving two first-order terms with variables. Unification is used in type inference in many programming languages and in the execution of logic programs. This means that unification algorithms have to be written over

Supersymmetric SU(5) GUT with Stabilized Moduli

CERN Document Server

Antoniadis, Ignatios; Panda, Binata

2008-01-01

We construct a minimal example of a supersymmetric grand unified model in a toroidal compactification of type I string theory with magnetized D9-branes. All geometric moduli are stabilized in terms of the background internal magnetic fluxes which are of "oblique" type (mutually non-commuting). The gauge symmetry is just SU(5) and the gauge non-singlet chiral spectrum contains only three families of quarks and leptons transforming in the $10+{\\bar 5}$ representations.

Cosmological origin of the grand-unification mass scale

International Nuclear Information System (INIS)

Brout, R.; Englert, F.; Spindel, P.

1979-01-01

The origin of the universe as a quantum phenomenon leads to a self-consistently generated space-time structure in which the mass of the created particles is O (kappa/sup -1/2/). We interpret the origin of the universe as a phase transition in which the grand unified symmetry is spontaneously broken

Supersymmetric composite models on intersecting D-branes

International Nuclear Information System (INIS)

Kitazawa, Noriaki

2004-01-01

We construct supersymmetric composite models of quarks and leptons from type IIA T6/(Z2xZ2) orientifold with intersecting D6-branes. In case of T6=T2xT2xT2 with no tilted T2, a composite model of supersymmetric SU(5) grand unified theory with four generations is constructed. In case of that one T2 is tilted, a composite model with SU(3)cxSU(2)LxU(1)Y gauge symmetry with three generations of left-handed quarks and leptons is constructed. These models are not realistic, but contain relatively fewer additional exotic particles and U(1) gauge symmetries due to the introduction of the compositeness of quarks and leptons. The masses of some exotic particles are naturally generated through the Yukawa interactions among 'preons'

Lepton flavor violation from supersymmetric grand unified theories: Where do we stand for MEG, PRISM/PRIME, and a super flavor factory

International Nuclear Information System (INIS)

Calibbi, L.; Faccia, A.; Masiero, A.; Vempati, S. K.

2006-01-01

We analyze the complementarity between lepton flavor violation (LFV) and LHC experiments in probing the supersymmetric (SUSY) grand unified theories (GUT) when neutrinos get a mass via the seesaw mechanism. Our analysis is performed in an SO(10) framework, where at least one neutrino Yukawa coupling is necessarily as large as the top Yukawa coupling. Our study thoroughly takes into account the whole renormalization group running, including the GUT and the right-handed neutrino mass scales, as well as the running of the observable neutrino spectrum. We find that the upcoming (MEG, SuperKEKB) and future (PRISM/PRIME, super flavor factory) LFV experiments will be able to test such SUSY framework for SUSY masses to be explored at the LHC and, in some cases, even beyond the LHC sensitivity reach

Electric dipole moments from Yukawa phases in supersymmetric theories

International Nuclear Information System (INIS)

Romanino, A.; Strumia, A.

1997-01-01

We study quark and electron EDMs generated by Yukawa couplings in supersymmetric models with different gauge groups, using the EDM properties under flavour transformations. In the MSSM (or if soft terms are mediated below the unification scale) the one-loop contributions to the neutron EDM are smaller than in previous computations based on numerical methods, although increasing as tan 3 β. A neutron EDM close to the experimental limits can be generated in SU(5), if tan β is large, through the u-quark EDM d u , proportional to tan 4 β. This effect has to be taken into account also in SO(10) with large tan β, where d u is comparable to the d quark EDM, proportional to tan β. (orig.)

Beyond the CMSSM without an accelerator: proton decay and direct dark matter detection

International Nuclear Information System (INIS)

Ellis, John; Evans, Jason L.; Olive, Keith A.; Luo, Feng; Nagata, Natsumi; Sandick, Pearl

2016-01-01

We consider two potential non-accelerator signatures of generalizations of the well-studied constrained minimal supersymmetric standard model (CMSSM). In one generalization, the universality constraints on soft supersymmetry-breaking parameters are applied at some input scale M in below the grand unification (GUT) scale M GUT , a scenario referred to as 'sub-GUT'. The other generalization we consider is to retain GUT-scale universality for the squark and slepton masses, but to relax universality for the soft supersymmetry-breaking contributions to the masses of the Higgs doublets. As with other CMSSM-like models, the measured Higgs mass requires supersymmetric particle masses near or beyond the TeV scale. Because of these rather heavy sparticle masses, the embedding of these CMSSM-like models in a minimal SU(5) model of grand unification can yield a proton lifetime consistent with current experimental limits, and may be accessible in existing and future proton decay experiments. Another possible signature of these CMSSM-like models is direct detection of supersymmetric dark matter. The direct dark matter scattering rate is typically below the reach of the LUX-ZEPLIN (LZ) experiment if M in is close to M GUT , but it may lie within its reach if M in

Introduction to supersymmetry in particle and nuclear physics

International Nuclear Information System (INIS)

Castanos, O.; Frank, A.; Urrutia, L.

1981-01-01

This book constitutes the proceedings of an International School of Supersymmetry held in Mexico City in 1981. Lectures presented include an introduction to supersymmetry (symmetries in relativistic quantum field theory, supersymmetry in quantum field theory, Dirac matrices and Majorana spinors, supersymmetric Yang-Mills theory, scalar multiplet and auxiliary fields, supergravity, N=1 supersymmetric theories, extended supersymmetry algebras, representations of extended supersymmetry, N=4 supersymmetric Yang-Mills theory, extended supergravity), superfields (irreducible representations and chiral superfields, invariants and ''tensor calculus,'' gauge superfield, N=1 supergravity), grand unification with and without supersymmetry (supersymmetric models), Yang-Mills theories with global and local supersymmetry (Higgs and Superhiggs effect in unified field theories), and supergroups and their representations (fermion and Grassmann numbers, supertrace and superdeterminant, harmonic oscillator representation, the Tilde operator, eigenvalues of Casimir operators, branching rules, Kac-Dynkin diagrams and supertableaux)

Upper bounds of supersymmetric particle masses in a gaugino-originated radiative breaking scenario

International Nuclear Information System (INIS)

Goto, T.

1993-01-01

The mass spectrum of supersymmetric particles is studied in the radiative breaking scenario of the minimal supersymmetric standard model, with an assumption that all soft supersymmetry-breaking parameters other than the gaugino masses are vanishing at the Planck scale. The U(1) gaugino mass M 1X is taken to be an independent parameter, while the SU(2) and SU(3) gaugino masses are supposed to be unified. Within the ''natural'' range, the whole parameter space is scanned numerically and the consistent particle mass spectra with the experimental bounds are obtained. The supersymmetric particle masses are tightly bounded above as m eR approx-lt 100 GeV, etc., if the top quark is sufficiently heavy m top approx-gt 100 GeV and the minimal grand unified theory relation for three gaugino masses is satisfied. For a large |M 1X |, there is no restriction other than the naturalness for the upper bounds of supersymmetric particle masses

A supersymmetric flipped SU(5) intersecting brane world

Energy Technology Data Exchange (ETDEWEB)

Chen, C.-M. [George P. and Cynthia W. Mitchell Institute for Fundamental Physics, Texas A and M University, College Station, TX 77843 (United States)]. E-mail: cchen@physics.tamu.edu; Kraniotis, G.V. [George P. and Cynthia W. Mitchell Institute for Fundamental Physics, Texas A and M University, College Station, TX 77843 (United States)]. E-mail: kraniotis@physics.tamu.edu; Mayes, V.E. [George P. and Cynthia W. Mitchell Institute for Fundamental Physics, Texas A and M University, College Station, TX 77843 (United States)]. E-mail: eric@physics.tamu.edu (and others)

2005-03-31

We construct an N=1 supersymmetric three-family flipped SU(5) model from type IIA orientifolds on T{sup 6}/(Z{sub 2}xZ{sub 2}) with D6-branes intersecting at general angles. The spectrum contains a complete grand unified and electroweak Higgs sector. In addition, it contains extra exotic matter both in bi-fundamental and vector-like representations as well as two copies of matter in the symmetric representation of SU(5)

Indirect search for neutralino dark matter with high energy neutrinos

International Nuclear Information System (INIS)

Barger, V.; Halzen, Francis; Hooper, Dan; Kao, Chung

2002-01-01

We investigate the prospects of indirect searches for supersymmetric neutralino dark matter. Relic neutralinos gravitationally accumulate in the Sun and their annihilations produce high energy neutrinos. Muon neutrinos of this origin can be seen in large detectors such as AMANDA, IceCube, and ANTARES. We evaluate the relic density and the detection rate in several models--the minimal supersymmetric model, minimal supergravity, and supergravity with nonuniversal Higgs boson masses at the grand unification scale. We make realistic estimates for the indirect detection rates including effects of the muon detection threshold, quark hadronization, and solar absorption. We find good prospects for detection of neutralinos with mass above 200 GeV

Supersymmetric seesaw inflection

International Nuclear Information System (INIS)

Aulakh, Charanjit S.; Garg, Ila

2013-01-01

We showed that Supersymmetric Unified theories which explain small neutrino masses via renormalizable Type-I-see-saw mechanism can also support slow roll inflection point inflation. In such a scenario inflation occurs along a MSSM D-flat direction associated with gauge invariant combination of Higgs, slepton and right handed sneutrino. The scale of inflation is set by right handed neutrino mass M υc ∼10 6 10 12 GeV and inflation parameters are determined in terms of Dirac and Majorana couplings responsible for neutrino masses. The fine tuning conditions to have effective slow roll inflation are determined in terms of superpotential parameters (Dirac and Majorana couplings). This is in contrast to MSSM or Dirac neutrino inflection scenarios where fine tuning conditions are on soft Susy breaking parameters. In our case M υc ≫ M Susy , so soft Susy breaking parameters have hardly any role to play in fine tuning. The fine tuning conditions are thus radiatively stable due to nonrenormalization theorems. Reheating occurs via instant preheating which dumps all the inflation energy into MSSM degrees of freedom giving a high reheat temperature T rh ≅ M υc 10 6 GeV ∼ 10 1l 10 15 GeV. We also examined how this scenario can be embedded in realistic New Minimal Supersymmetric SO(10) Grand Unified Theory. (author)

Grand unification in the projective plane

International Nuclear Information System (INIS)

Hebecker, A.

2004-01-01

A 6-dimensional grand unified theory with the compact space having the topology of a real projective plane, i.e., a 2-sphere with opposite points identified, is considered. The space is locally flat except for two conical singularities where the curvature is concentrated. One supersymmetry is preserved in the effective 4d theory. The unified gauge symmetry, for example SU(5), is broken only by the non-trivial global topology. In contrast to the Hosotani mechanism, no adjoint Wilson-line modulus associated with this breaking appears. Since, locally, SU(5) remains a good symmetry everywhere, no UV-sensitive threshold corrections arise and SU(5)-violating local operators are forbidden. Doublet-triplet splitting can be addressed in the context of a 6d N=2 super Yang-Mills theory with gauge group SU(6). If this symmetry is first broken to SU(5) at a fixed point and then further reduced to the standard model group in the above non-local way, the two light Higgs doublets of the MSSM are predicted by the group-theoretical and geometrical structure of the model. (author)

Proceedings of the fourth workshop on grand unification

Energy Technology Data Exchange (ETDEWEB)

Weldon, H.A.; Langacker, P.; Steinhardt, P.J.

1983-01-01

This book compiles the papers presented at the fourth conference of grand unified theories of nuclear physics held in University of Pennsylvania April 1983. The topics covered were proton decay theory; angular distribution and flux of atmospheric neutrinos; atmospheric neutrinos and astrophysical neutrinos in proton decay experiments; review of future nucleon decay experiments; monopole experiments; searches for magnetic monopole; monopoles, gauge, fields and anomalies; darkmatter, galaxies and voids; adiabatic fluctuations; supersymmetry, supergravity, and Kaluza-Klein theories; superstring theory and superunification.

Finite-temperature behavior of mass hierarchies in supersymmetric theories

International Nuclear Information System (INIS)

Ginsparg, P.

1982-01-01

It is shown that Witten's mechanism for producing a large gauge hierarchy in supersymmetric theories leads to a novel symmetry behavior at finite temperature. The exponentially large expectation value in such models develops at a critical temperature of order of the small (supersymmetry-breaking) scale. The phase transition can proceed without need of vacuum tunnelling. Models based on Witten's mechanism thus require a reexamination of the standard cosmological treatment of grand unified theories. (orig.)

Low-energy parity restoration and unification mass scale within maximal symmetries

Directory of Open Access Journals (Sweden)

Ajaya K. Mohanty

1984-01-01

Full Text Available We investigate the hierarchy of gauge boson masses in the maximal grand unified theory by studying the renormalization group equations for the running coupling constants associated with the symmetry breaking of SU(16viaSU(12 q×SU(4 l×U(1 |B|−|L| chain. Particular attention is given to the contribution of Higgs scalars to these equations. It is found that the intermediate mass scale ML, associated with right-handed gauge bosons could be as low as 10 3 GeV only for sin 2θ w(M L as high as 0.265 with α s(M L=0.13. In this chain of symmetry breaking, we have also examined the lowest unification mass that is allowed by the low-energy data for sin 2θ w(M L and the assumed gauge hierarchy. This has been done in two cases; first for the case where SU(3 c is vectorial, second, for the case where SU(3 c is axial. In both cases the lowest unification mass scales were found to be 10 13, 10 11, 10 8 and 10 7 GeV for sin 2θ w(M L = 0.22, 0.24, 0.26,and0.265 respectively with α s(M L = 0.13. The implication of these low unification masses on baryon non-conserving processes is also discussed.

SAT Encoding of Unification in EL

Science.gov (United States)

Baader, Franz; Morawska, Barbara

Unification in Description Logics has been proposed as a novel inference service that can, for example, be used to detect redundancies in ontologies. In a recent paper, we have shown that unification in EL is NP-complete, and thus of a complexity that is considerably lower than in other Description Logics of comparably restricted expressive power. In this paper, we introduce a new NP-algorithm for solving unification problems in EL, which is based on a reduction to satisfiability in propositional logic (SAT). The advantage of this new algorithm is, on the one hand, that it allows us to employ highly optimized state-of-the-art SAT solvers when implementing an EL-unification algorithm. On the other hand, this reduction provides us with a proof of the fact that EL-unification is in NP that is much simpler than the one given in our previous paper on EL-unification.

Two new supersymmetric equations of Harry Dym type and their supersymmetric reciprocal transformations

International Nuclear Information System (INIS)

Tian, Kai; Liu, Q.P.

2012-01-01

A new N=1 supersymmetric Harry Dym equation is constructed by applying supersymmetric reciprocal transformation to a trivial supersymmetric Harry Dym equation, and its recursion operator and Lax formulation are also obtained. Within the framework of symmetry approach, a class of 3rd order supersymmetric equations of Harry Dym type are considered. In addition to five known integrable equations, a new supersymmetric equation, admitting 5th order generalized symmetry, is shown to be linearizable through supersymmetric reciprocal transformation. Furthermore, its Lax representation and recursion operator are given so that the integrability of this new equation is confirmed. -- Highlights: ► A new supersymmetric Harry Dym equation is constructed through supersymmetric reciprocal transformations. ► The recursion operator and Lax formulation are established for the new supersymmetric Harry Dym equation. ► A supersymmetric equation of Harry Dym type is shown to be linearized through supersymmetric reciprocal transformation.

A Singlet Extension of the Minimal Supersymmetric Standard Model: Towards a More Natural Solution to the Little Hierarchy Problem

Energy Technology Data Exchange (ETDEWEB)

de la Puente, Alejandro [Univ. of Notre Dame, IN (United States)

2012-05-01

In this work, I present a generalization of the Next-to-Minimal Supersymmetric Standard Model (NMSSM), with an explicit μ-term and a supersymmetric mass for the singlet superfield, as a route to alleviating the little hierarchy problem of the Minimal Supersymmetric Standard Model (MSSM). I analyze two limiting cases of the model, characterized by the size of the supersymmetric mass for the singlet superfield. The small and large limits of this mass parameter are studied, and I find that I can generate masses for the lightest neutral Higgs boson up to 140 GeV with top squarks below the TeV scale, all couplings perturbative up to the gauge unification scale, and with no need to fine tune parameters in the scalar potential. This model, which I call the S-MSSM is also embedded in a gauge-mediated supersymmetry breaking scheme. I find that even with a minimal embedding of the S-MSSM into a gauge mediated scheme, the mass for the lightest Higgs boson can easily be above 114 GeV, while keeping the top squarks below the TeV scale. Furthermore, I also study the forward-backward asymmetry in the t¯t system within the framework of the S-MSSM. For this purpose, non-renormalizable couplings between the first and third generation of quarks to scalars are introduced. The two limiting cases of the S-MSSM, characterized by the size of the supersymmetric mass for the singlet superfield is analyzed, and I find that in the region of small singlet supersymmetric mass a large asymmetry can be obtained while being consistent with constraints arising from flavor physics, quark masses and top quark decays.

Cosmological implications of grand unified theories

International Nuclear Information System (INIS)

Nanopoulos, D.V.

1982-01-01

These lectures, mainly devoted to the cosmological implications of GUTs, also include the essential ingredients of GUTs and some of their important applications to particle physics. Section 1 contains some basic points concerning the structure of the standard strong and electroweak interactions prior to grand unification. A detailed expose of GUTs is attempted in sect. 2, including their basci principles and their consequences for particle physics. The minimal, simplest GUT, SU 5 is analysed in some detail and it will be used throughout these lectures as the GUT prototype. Finally, sect. 3 contains the most important cosmological implications of GUTs, including baryon number generation in the early Universe (in rather lengthy detail), dissipative processes in the very early Universe, grand unified monopoles, etc. (orig./HSI)

Roadmap of left-right models based on GUTs

Science.gov (United States)

Chakrabortty, Joydeep; Maji, Rinku; Patra, Sunando Kumar; Srivastava, Tripurari; Mohanty, Subhendra

2018-05-01

We perform a detailed study of the grand unified theories S O (10 ) and E (6 ) with left-right intermediate gauge symmetries of the form S U (N )L⊗S U (N )R⊗G . Proton decay lifetime constrains the unification scale to be ≳1016 GeV and, as discussed in this paper, unwanted cosmological relics can be evaded if the intermediate symmetry scale is ≳1012 GeV . With these conditions, we study the renormalization group evolution of the gauge couplings and do a comparative analysis of all possible left-right models where unification can occur. Both the D-parity conserved and broken scenarios as well as the supersymmetric (SUSY) and nonsupersymmetric (non-SUSY) versions are considered. In addition to the fermion and scalar representations at each stage of the symmetry breaking, contributing to the β functions, we list the intermediate left-right groups that successfully meet these requirements. We make use of the dimension-5 kinetic mixing effective operators for achieving unification and large intermediate scale. A significant result in the supersymmetric case is that to achieve successful unification for some breaking patterns, the scale of SUSY breaking needs to be at least a few TeV. In some of these cases, the intermediate scale can be as low as ˜1012 GeV , for the SUSY scale to be ˜30 TeV . This has important consequences in the collider searches for SUSY particles and phenomenology of the lightest neutralino as dark matter.

Low-scale gaugino mass unification

International Nuclear Information System (INIS)

Endo, M.; Yoshioka, K.

2008-04-01

We present a new class of scenarios with the gaugino mass unification at the weak scale. The unification conditions are generally classified and then, the mirage gauge mediation is explored where gaugino masses are naturally unified and scalar partners of quarks and leptons have no mass hierarchy. The low-energy mass spectrum is governed by the mirage of unified gauge coupling which is seen by low-energy observers. We also study several explicit models for dynamically realizing the TeV-scale unification. (orig.)

Low-scale gaugino mass unification

Energy Technology Data Exchange (ETDEWEB)

Endo, M [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Yoshioka, K [Kyoto Univ. (Japan). Dept. of Physics

2008-04-15

We present a new class of scenarios with the gaugino mass unification at the weak scale. The unification conditions are generally classified and then, the mirage gauge mediation is explored where gaugino masses are naturally unified and scalar partners of quarks and leptons have no mass hierarchy. The low-energy mass spectrum is governed by the mirage of unified gauge coupling which is seen by low-energy observers. We also study several explicit models for dynamically realizing the TeV-scale unification. (orig.)

Neutrino masses and large mixings as a indirect signature of grand unified theory

International Nuclear Information System (INIS)

Maekawa, Nobuhiro

2015-01-01

Grand unified theory (GUT) unifies not only three forces (electromagnetic force, strong force and weak force) but also quarks and leptons. As an experimental support for the unification of forces, it is well-known that three gauge couplings meet at a scale (the GUT scale). However, it is not so well-known that there is an experimental support even for the unification of matters (quarks and leptons). We explain the indirect support in this document and show that the important key is what the neutrino experiments have revealed for 20 years. Concretely, for the unification of matters in SU(5) GUT, various observed hierarchies of quark and lepton masses and mixings can be understood only from one assumption that '10 dimensional fields of SU(5) induce stronger hierarchy for the Yukawa couplings than 5-bar fields'. For this explanation, the knowledges on neutrino masses and mixings are critical. In the end, we comment E 6 unification in which the above assumption in the SU(5) GUT can be induced. (author)

Testing GUTs: where do monopoles fit

International Nuclear Information System (INIS)

Ellis, J.

1982-10-01

The report shows why the inadequacies of the standard model of elementary particles impel some theorists toward embedding the strong, weak and electromagnetic interactions in a simple GUT group, and explains why the grand unification scale and hence the GUM (Grand Unified Monopoles) mass are expected to be so large (greater than or equal to 10 14 GeV). It goes on to describe some model GUTs, notably minimal SU(5) and supersymmetric (susy) GUTs. The grand unified analogues of generalized Cabibbo mixing angles are introduced relevant to the prediction of baryon decay modes in different theories as well as to the Decay modes catalyzed by GUMs. Phenomenologies of conventional and susy GUTs are contrasted including the potential increase in the grand unification scale as well as possible different baryon decay modes in susy GUTs. The phenomenology of GUMs is discussed, principally their ability to catalyze baryon decays. Some of the astrophysical and cosmological constraints on GUMs, GUMs, which make it difficult to imagine ever seeing a GUM and may impose serious restrictions on GUT model-building via their behavior in the very early universe are introduced. Finally, the reasons why GUMs are crucial aspects and tests of GUTs are summarized

The heavy top quark and supersymmetry

Energy Technology Data Exchange (ETDEWEB)

Hall, L.J. [Lawrence Berkeley Lab., CA (United States)]|[Univ. of California, Berkeley, CA (United States)

1997-01-01

Three aspects of supersymmetric theories are discussed: electroweak symmetry breaking, the issues of flavor, and gauge unification. The heavy top quark plays an important, sometimes dominant, role in each case. Additional symmetries lead to extensions of the Standard Model which can provide an understanding for many of the outstanding problems of particle physics. A broken supersymmetric extension of spacetime allows electroweak symmetry breaking to follow from the dynamics of the heavy top quark; an extension of isospin provides a constrained framework for understanding the pattern of quark and lepton masses; and a grand unified extension of the Standard Model gauge group provides an elegant understanding of the gauge quantum numbers of the components of a generation. Experimental signatures for each of these additional symmetries are discussed.

The heavy top quark and supersymmetry

International Nuclear Information System (INIS)

Hall, L.J.; Univ. of California, Berkeley, CA

1996-01-01

Three aspects of supersymmetric theories are discussed: electroweak symmetry breaking, the issues of flavor, and gauge unification. The heavy top quark plays an important, sometimes dominant, role in each case. Additional symmetries lead to extensions of the standard model which can provide an understanding for many of the outstanding problems of particle physics. A broken supersymmetric extension of spacetime allows electroweak symmetry breaking to follow from the dynamics of the heavy top quark; an extension of isospin provides a constrained framework for understanding the pattern of quark and lepton masses; and a grand unified extension of the standard model gauge group provides an elegant understanding of the gauge quantum numbers of the components of a generation. Experimental signatures for each of these additional symmetries are discussed

The heavy top quark and supersymmetry

International Nuclear Information System (INIS)

Hall, L.J.

1997-01-01

Three aspects of supersymmetric theories are discussed: electroweak symmetry breaking, the issues of flavor, and gauge unification. The heavy top quark plays an important, sometimes dominant, role in each case. Additional symmetries lead to extensions of the Standard Model which can provide an understanding for many of the outstanding problems of particle physics. A broken supersymmetric extension of spacetime allows electroweak symmetry breaking to follow from the dynamics of the heavy top quark; an extension of isospin provides a constrained framework for understanding the pattern of quark and lepton masses; and a grand unified extension of the Standard Model gauge group provides an elegant understanding of the gauge quantum numbers of the components of a generation. Experimental signatures for each of these additional symmetries are discussed

Flipped version of the supersymmetric strongly coupled preon model

Energy Technology Data Exchange (ETDEWEB)

Fajfer, S. (Institut za Fiziku, University of Sarajevo, Sarajevo, (Yugoslavia)); Milekovic, M.; Tadic, D. (Zavod za Teorijsku Fiziku, Prirodoslovno-Matematicki Fakultet, University of Zagreb, Croatia, (Yugoslavia))

1989-12-01

In the supersymmetric SU(5) (SUSY SU(5)) composite model (which was described in an earlier paper) the fermion mass terms can be easily constructed. The SUSY SU(5){direct product}U(1), i.e., flipped, composite model possesses a completely analogous composite-particle spectrum. However, in that model one cannot construct a renormalizable superpotential which would generate fermion mass terms. This contrasts with the standard noncomposite grand unified theories (GUT's) in which both the Georgi-Glashow electrical charge embedding and its flipped counterpart lead to the renormalizable theories.

Grand unified theory precursors and nontrivial fixed points in higher-dimensional gauge theories

International Nuclear Information System (INIS)

Dienes, Keith R.; Dudas, Emilian; Gherghetta, Tony

2003-01-01

Within the context of traditional logarithmic grand unification at M GUT ≅10 16 GeV, we show that it is nevertheless possible to observe certain GUT states such as X and Y gauge bosons at lower scales, perhaps even in the TeV range. We refer to such states as 'GUT precursors'. These states offer an interesting alternative possibility for new physics at the TeV scale, and could be used to directly probe GUT physics even though the scale of gauge coupling unification remains high. Our results also give rise to a Kaluza-Klein realization of nontrivial fixed points in higher-dimensional gauge theories

Oasis in the desert: weakly broken parity in grand unified theories

International Nuclear Information System (INIS)

Senjanovic, G.

1981-07-01

A discussion of low energy parity restoration in simple grand unified theories, such as SO(10), is presented. The consistency of phenomenological requirements and unification constraints is emphasized and various predictions of the theory are stressed, in particular: substantially lighter W and Z bosons than in the standard model and increased stability of the proton with tau/sub p/ approx. = 10 38 years

Proton decay: Numerical simulations confront grand unification

International Nuclear Information System (INIS)

Brower, R.C.; Maturana, G.; Giles, R.C.; Moriarty, K.J.M.; Samuel, S.

1985-01-01

The Grand Unified Theories of the electromagnetic, weak and strong interactions constitute a far reaching attempt to synthesize our knowledge of theoretical particle physics into a consistent and compelling whole. Unfortunately, many quantitative predictions of such unified theories are sensitive to the analytically intractible effects of the strong subnuclear theory (Quantum Chromodynamics or QCD). The consequence is that even ambitious experimental programs exploring weak and super-weak interaction effects often fail to give definitive theoretical tests. This paper describes large-scale calculations on a supercomputer which can help to overcome this gap between theoretical predictions and experimental results. Our focus here is on proton decay, though the methods described are useful for many weak processes. The basic algorithms for the numerical simulation of QCD are well known. We will discuss the advantages and challenges of applying these methods to weak transitions. The algorithms require a very large data base with regular data flow and are natural candidates for vectorization. Also, 32-bit floating point arithmetic is adequate. Thus they are most naturally approached using a supercomputer alone or in combination with a dedicated special purpose processor. (orig.)

Technicolor and Beyond: Unification in Theory Space

International Nuclear Information System (INIS)

Sannino, Francesco

2010-01-01

I will briefly review the salient features of models of dynamical electroweak symmetry breaking together with the traditional extensions needed to provide masses to the standard model fermions in absence of fundamental scalars. The idea walking idea is introduced according to which one should carefully take into account the effects of the extended technicolor dynamics on the technicolor dynamics itself. The interplay between the four fermion interactions stemming from the extended technicolor interactions and the technicolor model can strongly enhance the anomalous dimension of the mass of the techniquarks allowing to decouple the Flavor Changing Neutral Currents problem from the one of the generation of the large top mass. I will also review the Minimal Walking Technicolor (MWT) models. In the second part of this review I consider the interesting possibility to marry supersymmetry and technicolor. The reason is to provide a unification of different extensions of the standard model. For example, this means that one can recover, according to the parameters and spectrum of the theory distinct extensions of the standard model, from supersymmetry to technicolor and unparticle physiscs. A surprising result is that a minimal (in terms of the smallest number of fields) supersymmetrization of the MWT model leads to the maximal supersymmetry in four dimensions, i.e. N = 4 SYM.

Studying gaugino mass unification at the LHC

International Nuclear Information System (INIS)

Altunkaynak, Baris; Holmes, Michael; Nelson, Brent D.; Grajek, Phillip; Kane, Gordon

2009-01-01

We begin a systematic study of how gaugino mass unification can be probed at the CERN Large Hadron Collider (LHC) in a quasi-model independent manner. As a first step in that direction we focus our attention on the theoretically well-motivated mirage pattern of gaugino masses, a one-parameter family of models of which universal (high scale) gaugino masses are a limiting case. We improve on previous methods to define an analytic expression for the metric on signature space and use it to study one-parameter deviations from universality in the gaugino sector, randomizing over other soft supersymmetry-breaking parameters. We put forward three ensembles of observables targeted at the physics of the gaugino sector, allowing for a determination of this non-universality parameter without reconstructing individual mass eigenvalues or the soft supersymmetry-breaking gaugino masses themselves. In this controlled environment we find that approximately 80% of the supersymmetric parameter space would give rise to a model for which our method will detect non-universality in the gaugino mass sector at the 10% level with O(10 fb -1 ) of integrated luminosity. We discuss strategies for improving the method and for adding more realism in dealing with the actual experimental circumstances of the LHC.

Supersymmetric color superconductivity

International Nuclear Information System (INIS)

Harnik, Roni; Larson, Daniel T.; Murayama, Hitoshi

2003-01-01

Recent interest in novel phases in high density QCD motivates the study of high density supersymmetric QCD (SQCD), where powerful exact results for supersymmetric gauge theories can be brought to bear in the strongly coupled regime. We begin by describing how a chemical potential can be incorporated into a supersymmetric theory as a spurion vector superfield. We then study supersymmetric SU(N c ) gauge theories with N f flavors of quarks in the presence of a baryon chemical potential μ, and describe the global symmetry breaking patterns at low energy. Our analysis requires μ > Λ. We find that for N F c a modified U(1) B symmetry is preserved, analogous to the non-supersymmetric 2SC phase, whereas for N f = N c there is a critical chemical potential above which the U(1) B is broken, as it is in the non-supersymmetric CFL phase. We further analyze the cases with N c + 1 (le) N f c and find that baryon number is broken dynamically for μ > μ c . We also give a qualitative description of the phases in the ''conformal window'', 3/2 N c f c , at finite density

Supersymmetric color superconductivity

International Nuclear Information System (INIS)

Harnik, Roni; Larson, Daniel T.; Murayama, Hitoshi

2004-01-01

Recent interest in novel phases in high density QCD motivates the study of high density supersymmetric QCD (SQCD), where powerful exact results for supersymmetric gauge theories can be brought to bear in the strongly coupled regime. We begin by describing how a chemical potential can be incorporated into a supersymmetric theory as a spurion vector superfield. We then study supersymmetric SU(N c ) gauge theories with N f flavors of quarks in the presence of a baryon chemical potential mu, and describe the global symmetry breaking patterns at low energy. Our analysis requires μ f c a modified U(1) B symmetry is preserved, analogous to the non-supersymmetric 2SC phase, whereas for N f =N c there is a critical chemical potential above which the U(1) B is broken, as it is in the non-supersymmetric CFL phase. We further analyze the cases with N c +1≤ N f c and find that baryon number is broken dynamically for μ > mu c . We also give a qualitative description of the phases in the 'conformal window', 3/2 N c f c , at finite density. (author)

Theory, phenomenology, and prospects for detection of supersymmetric dark matter

International Nuclear Information System (INIS)

Diehl, E.; Kane, G.L.; Kolda, C.; Wells, J.D.

1995-01-01

One of the great attractions of minimal superunified supersymmetric models is the prediction of a massive, stable, weakly interacting particle [the lightest supersymmetric partner (LSP)] which can have the right relic abundance to be a cold dark matter candidate. In this paper we investigate the identity, mass, and properties of the LSP after requiring gauge coupling unification, proper electroweak symmetry breaking, and numerous phenomenological constraints. We then discuss the prospects for detecting the LSP. The experiments which we investigate are (1) space annihilations into positrons, antiprotons, and γ rays, (2) large underground arrays to detect upward-going muons arising from LSP capture and annihilation in the sun and earth, (3) elastic collisions on matter in a table top apparatus, and (4) production of LSP's or decays into LSP's at high energy colliders. Our conclusions are that space annihilation experiments and large underground detectors are of limited help in initially detecting the LSP although perhaps they could provide confirmation of a signal seen in other experiments, while table top detectors have considerable discovery potential. Colliders such as the CERN LEP II, an upgraded Fermilab, and the CERN LHC might be the best dark matter detectors of all. This paper improves on most previous analyses in the literature by (a) only considering parameters not already excluded by several physics constraints listed above, (b) presenting results that are independent of (usually untenable) parameter choices, (c) comparing opportunities to study the same cold dark matter, and (d) including minor technical improvements

Quark and lepton masses at the GUT scale including supersymmetric threshold corrections

International Nuclear Information System (INIS)

Antusch, S.; Spinrath, M.

2008-01-01

We investigate the effect of supersymmetric (SUSY) threshold corrections on the values of the running quark and charged lepton masses at the grand unified theory (GUT) scale within the large tanβ regime of the minimal supersymmetric standard model. In addition to the typically dominant SUSY QCD contributions for the quarks, we also include the electroweak contributions for quarks and leptons and show that they can have significant effects. We provide the GUT scale ranges of quark and charged lepton Yukawa couplings as well as of the ratios m μ /m s , m e /m d , y τ /y b and y t /y b for three example ranges of SUSY parameters. We discuss how the enlarged ranges due to threshold effects might open up new possibilities for constructing GUT models of fermion masses and mixings.

String flipped SO(10) model from [ital Z][sub 4] orbifold

Energy Technology Data Exchange (ETDEWEB)

Sato, H. (Department of Physics, Hyogo University of Education, Yashiro-cho, Hyogo 673-14 (Japan)); Shimojo, M. (Department of Electronics and Information Engineering, Fukui National College of Technology, Sabae, Fukui 916 (Japan))

1993-12-15

We search all possible string grand-unified-theory models obtained from heterotic superstrings compactified on a [ital Z][sub 4] orbifold with one Wilson line. It is shown that there is an essentially unique anomaly-free flipped SO(10) model with three generations plus one mirror conjugate generation of matter fields. We derive effective Yukawa interactions and examine the structure of mass matrices as well as a possible scenario of string coupling unification. The four-generation [ital Z][sub 4] orbifold model is a phenomenologically viable model beyond the minimal supersymmetric standard one.

String flipped SO(10) model from Z4 orbifold

International Nuclear Information System (INIS)

Sato, H.; Shimojo, M.

1993-01-01

We search all possible string grand-unified-theory models obtained from heterotic superstrings compactified on a Z 4 orbifold with one Wilson line. It is shown that there is an essentially unique anomaly-free flipped SO(10) model with three generations plus one mirror conjugate generation of matter fields. We derive effective Yukawa interactions and examine the structure of mass matrices as well as a possible scenario of string coupling unification. The four-generation Z 4 orbifold model is a phenomenologically viable model beyond the minimal supersymmetric standard one

New initiatives on lepton flavor violation and neutrino oscillation with high intense muon and neutrino sources

CERN Document Server

Kuno, Yoshitaka; Pakvasa, Sandip

2002-01-01

The area of physics involving muons and neutrinos has become exciting in particle physics. Using their high intensity sources, physicists undertake, in various ways, extensive searches for new physics beyond the Standard Model, such as tests of supersymmetric grand unification (SUSY-GUT) and precision measurements of the muon and neutrino properties, which will in future extend to ambitious studies such as determination of the three-generation neutrino mixing matrix elements and CP violation in the lepton sector. The physics of this field is advancing, with potential improvements of the source

On grand unified SU(8)sub(L) x SU(8)sub(R) model

International Nuclear Information System (INIS)

Pirogov, Yu.F.

1980-01-01

In the model of early chiral grand unification SU(8)sub(L)xSU(8)sub(R) with intermediate symmetry hierarchies the radiation corrections for sinsup(2)thetasub(W)(μ) and α(μ) are calculated and unification mass M 8 is found in the one loop approximation with Higgs fields contribution being neglected. It is shown that there exists a natural hierarchy, leading to the decrease of sinsup(2)thetasub(W)(Msub(W)) down to the value sinsup(2)thetasub(W)=1/5-1/4 and simultaneous decrease of M 8 down to M 8 =(10 6 -10 7 ) GeV as compared with the values when there is no hierarchy [ru

Supersymmetric reciprocal transformation and its applications

International Nuclear Information System (INIS)

Liu, Q. P.; Popowicz, Ziemowit; Tian Kai

2010-01-01

The supersymmetric analog of the reciprocal transformation is introduced. This is used to establish a transformation between one of the supersymmetric Harry Dym equations and the supersymmetric modified Korteweg-de Vries equation. The reciprocal transformation, as a Baecklund-type transformation between these two equations, is adopted to construct a recursion operator for the supersymmetric Harry Dym equation. By proper factorization of the recursion operator, a bi-Hamiltonian structure is found for the supersymmetric Harry Dym equation. Furthermore, a supersymmetric Kawamoto equation is proposed and is associated with the supersymmetric Sawada-Kotera equation. The recursion operator and odd bi-Hamiltonian structure of the supersymmetric Kawamoto equation are also constructed.

Natural embedding of Peccei-Quinn symmetry in flavor grand unification

International Nuclear Information System (INIS)

Kim, J.E.

1981-08-01

Peccei and Quinn's global U(1)sub(A) symmetry can be embedded in grand unified schemes without an artificial requirement of imposing U(1)sub(A) symmetry, which results from the representation content of fermions and Higgs fields. Then, in some cases there results an ordinary axion with a mass approximately 100 keV. The axion mass is proportional to v -1 sub(A), where v -1 sub(A) is the scale of the actual U(1)sub(A) symmetry breakdown. (author)

Advantages of unity with SU(4)-color: Reflections through neutrino oscillations, baryogenesis and proton decay

Science.gov (United States)

Pati, Jogesh C.

2017-03-01

fact turned out to be an asset. They are needed to (a) understand naturally the tiny mass-scales observed in neutrino oscillations by combining the seesaw mechanism together with the unification ideas based on the symmetry SU(4)-color, and also (b) to implement the attractive mechanism of baryogenesis via leptogenesis. The quantitative success of the attempts as regards understanding both (a) and (b) are discussed in Sec. 6. These provide a clear support simultaneously for the following three features: (i) the seesaw mechanism, (ii) the SU(4)-color route to higher unification based on a symmetry like SO(10) or a string-derived G(2, 2, 4) symmetry in 4D, as opposed to alternative symmetries like SU(5) or even [SU(3)]3, and (iii) the (B-L)-breaking scale being close to the unification scale ˜ 2 × 1016 GeV. The observed dramatic meeting of the three gauge couplings in the context of low-energy supersymmetry, at a scale MU ˜ 2 × 1016 GeV, providing strong evidence in favor of the ideas of both grand unification and supersymmetry, is discussed in Sec. 3. The implications of such a meeting in the context of string-unification are briefly mentioned. Weighing the possibility of a stringy origin of gauge coupling unification versus the familiar problem of doublet-triplet splitting in supersymmetric SO(10) (or SU(5)), I discuss the common advantages as well as relative merits and demerits of an effective SO(10) versus a string-derived G(2, 2, 4) symmetry in 4D. In Sec. 7, I discuss the hallmark prediction of grand unification, viz. proton decay, which is a generic feature of most models of grand unification. I present results of works carried out in collaboration with Babu and Wilczek and most recently with Babu and Tavartkiladze on expectations for decay modes and lifetimes for proton decay, including upper limits for such lifetimes, in the context of a well-motivated class of supersymmetric SO(10)-models. In view of such expectations, I stress the pressing need for having

Supersymmetric classical mechanics

International Nuclear Information System (INIS)

Biswas, S.N.; Soni, S.K.

1986-01-01

The purpose of the paper is to construct a supersymmetric Lagrangian within the framework of classical mechanics which would be regarded as a candidate for passage to supersymmetric quantum mechanics. 5 refs. (author)

Supersymmetric quasipotential equations

International Nuclear Information System (INIS)

Zaikov, R.P.

1981-01-01

A supersymmetric extension of the Logunov-Tavkhelidze quasipotential approach is suggested. The supersymmetric Bethe- Salpeter equation is an initial equation. The transition from the four-time to the two-time Green function is made in the super- center-of-mass system. The two-time Green function has no inverse function in the whole spinor space. The resolvent operator if found using the Majorana character of the spinor wave function. The supersymmetric quasipotential equation is written. The consideration is carried out in the framework of the theory of chiral scalar superfields [ru

Higher-derivative Lee-Wick unification

International Nuclear Information System (INIS)

Carone, Christopher D.

2009-01-01

We consider gauge coupling unification in Lee-Wick extensions of the Standard Model that include higher-derivative quadratic terms beyond the minimally required set. We determine how the beta functions are modified when some Standard Model particles have two Lee-Wick partners. We show that gauge coupling unification can be achieved in such models without requiring the introduction of additional fields in the higher-derivative theory and we comment on possible ultraviolet completions.

Proton decay in grand unified theories

International Nuclear Information System (INIS)

Lucha, W.

1984-01-01

Interactions which violate the conservation of baryon and lepton number represent an intrinsic part of all grand unified theories (GUTs) of strong and electroweak interactions. These new interactions - predicted within the framework of GUTs - generate B and L violating four-fermion interactions via the exchange of superheavy particles which cannot be ascribed a well-defined baryon or lepton number. The effective coupling constant of these four-fermion interactions might be large enough to make the proton decay detectable by the present generation of experiments. In this review the basic concepts of conventional as well as supersymmetric GUTs relevant for proton decay are sketched. The baryon number violating sector of grand unified theories is discussed in more detail. Special emphasis is laid on the various selection rules arising as consequences of low-energy gauge invariance and supersymmetry for proton decay. These selection rules already determine the coarse pattern of the resulting decay modes and branching ratios without any reference to or detailed knowledge of the underlying grand unified theory. Finally the numerous theoretical predictions are summarized and confronted with experiment. (Author)

SU(8) family unification with boson-fermion balance

CERN Multimedia

CERN. Geneva

2014-01-01

Grand unification has been intensively investigated for over forty years, and many different approaches have been tried. In this talk I propose a model that involves three ingredients that do not appear in the usual constructions: (1) boson--fermion balance without full supersymmetry, (2) canceling the spin 1/2 fermion gauge anomalies against the anomaly from a gauged spin 3/2 gravitino, and (3) using a scalar field representation with non-zero U(1) generator to break the SU(8) gauge symmetry through a ground state which, before dynamical symmetry breaking, has a periodic U(1) generator structure. The model has a number of promising features: (1) natural incorporation of three families, (2) incorporation of the experimentally viable flipped SU(5) model, (3) a symmetry breaking pathway to the standard model using the scalar field required by boson-fermion balance, together with a stage of most attractive channel dynamical symmetry breaking, without postulating additional Higgs fields, (4) vanishing of bare Yuk...

Lie groups and grand unified theories

International Nuclear Information System (INIS)

Gubitoso, M.D.

1987-01-01

This work presents some concepts in group theory and Lie algebras and, at same time, shows a method to study and work with semisimple Lie groups, based on Dynkin diagrams. The aproach taken is not completely formal, but it presents the main points of the elaboration of the method, so its mathematical basis is designed with the purpose of making the reading not so cumbersome to those who are interested only in a general picture of the method and its usefulness. At the end it is shown a brief review of gauge theories and two grand-unification models based on SO(13) and E 7 gauge groups. (author) [pt

Supersymmetric domain walls

NARCIS (Netherlands)

Bergshoeff, Eric A.; Kleinschmidt, Axel; Riccioni, Fabio

2012-01-01

We classify the half-supersymmetric "domain walls," i.e., branes of codimension one, in toroidally compactified IIA/IIB string theory and show to which gauged supergravity theory each of these domain walls belong. We use as input the requirement of supersymmetric Wess-Zumino terms, the properties of

Spin analysis of supersymmetric particles

International Nuclear Information System (INIS)

Choi, S.Y.; Martyn, H.U.

2006-12-01

The spin of supersymmetric particles can be determined at e + e - colliders unambiguously. This is demonstrated for a characteristic set of non-colored supersymmetric particles -- smuons, selectrons, and charginos/neutralinos. The analysis is based on the threshold behavior of the excitation curves for pair production in e + e - collisions, the angular distribution in the production process and decay angular distributions. In the first step we present the observables in the helicity formalism for the supersymmetric particles. Subsequently we confront the results with corresponding analyses of Kaluza-Klein particles in theories of universal extra space dimensions which behave distinctly different from supersymmetric theories. It is shown in the third step that a set of observables can be designed which signal the spin of supersymmetric particles unambiguously without any model assumptions. Finally in the fourth step it is demonstrated that the determination of the spin of supersymmetric particles can be performed experimentally in practice at an e + e - collider. (orig.)

Properties of supersymmetric particles and processes

International Nuclear Information System (INIS)

Barnett, R.M.

1986-01-01

The motivations for experimental searches for supersymmetric particles are discussed. The role of R-parity in these searches is described. The production and decay characteristics of each class of supersymmetric particles are investigated in the context of both e+e- and hadron machines. There is a detailed presentation of a sample calculation of a supersymmetric process. Emphasis is given to the signatures for detection of supersymmetric particles and processes. The current limits for supersymmetric particles are given. 125 refs., 50 figs

Phenomenological Hints from a Class of String Motivated Model Constructions

Directory of Open Access Journals (Sweden)

Hans Peter Nilles

2015-01-01

Full Text Available We use string theory constructions towards the generalisation of the supersymmetric standard model of strong and electroweak interactions. Properties of the models depend crucially on the location of fields in extradimensional compact space. This allows us to extract some generic lessons for the phenomenological properties of the low energy effective action. Within this scheme we present a compelling model based on local grand unification and mirage mediation of supersymmetry breakdown. We analyse the properties of the specific model towards its possible tests at the LHC and the complementarity to direct dark matter searches.

Left-right gauge symmetry breaking by radiative corrections in supergravity

International Nuclear Information System (INIS)

Moxhay, P.; Yamamoto, K.

1984-01-01

A supersymmetric SU(2)sub(L) x SU(2)sub(R) x U(1)sub(B-L) gauge theory coupled to N = 1 supergravity is investigated. The scale of left-right gauge symmetry breaking is determined as Msub(R) proportional Msub(P) esup(-1/α) by radiative corrections through the logarithmic evolution of soft supersymmetry breakings. SU(2)sub(L) x SU(2)sub(R) x U(1)sub(B-L) may be embedded in SO(10) grand unification. Cosmological implications intrinsic to the present model are also discussed, which may give a constraint Msub(R) approx.= 10 9-12 GeV. (orig.)

The neutralino sector in the U(1)-extended supersymmetric standard model

Energy Technology Data Exchange (ETDEWEB)

Choi, S.Y. [Chonbuk National Univ., Jeonju (Korea). Dept. of Physics and RIPC]|[Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Haber, H.E. [California Univ., Santa Cruz, CA (United States). SCIPP; Kalinowski, J. [Warsaw Univ. (Poland). Inst. of Theoretical Physics; Zerwas, P.M. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)]|[California Univ., Santa Cruz, CA (United States). SCIPP

2006-12-15

Motivated by grand unified theories and string theories we analyze the general structure of the neutralino sector in the USSM, an extension of the Minimal Supersymmetric Standard Model that involves a broken extra U(1) gauge symmetry. This supersymmetric U(1)-extended model includes an Abelian gauge superfield and a Higgs singlet superfield in addition to the standard gauge and Higgs superfields of the MSSM. The interactions between the MSSM fields and the new fields are in general weak and the mixing is small, so that the coupling of the two subsystems can be treated perturbatively. As a result, the mass spectrum and mixing matrix in the neutralino sector can be analyzed analytically and the structure of this 6-state system is under good theoretical control. We describe the decay modes of the new states and the impact of this extension on decays of the original MSSM neutralinos, including radiative transitions in cross-over zones. Production channels in cascade decays at the LHC and pair production at e{sup +}e{sup -} colliders are also discussed. (orig.)

The minimal GUT with inflaton and dark matter unification

Science.gov (United States)

Chen, Heng-Yu; Gogoladze, Ilia; Hu, Shan; Li, Tianjun; Wu, Lina

2018-01-01

Giving up the solutions to the fine-tuning problems, we propose the non-supersymmetric flipped SU(5)× U(1)_X model based on the minimal particle content principle, which can be constructed from the four-dimensional SO(10) models, five-dimensional orbifold SO(10) models, and local F-theory SO(10) models. To achieve gauge coupling unification, we introduce one pair of vector-like fermions, which form a complete SU(5)× U(1)_X representation. The proton lifetime is around 5× 10^{35} years, neutrino masses and mixing can be explained via the seesaw mechanism, baryon asymmetry can be generated via leptogenesis, and the vacuum stability problem can be solved as well. In particular, we propose that inflaton and dark matter particles can be unified to a real scalar field with Z_2 symmetry, which is not an axion and does not have the non-minimal coupling to gravity. Such a kind of scenarios can be applied to the generic scalar dark matter models. Also, we find that the vector-like particle corrections to the B_s^0 masses might be about 6.6%, while their corrections to the K^0 and B_d^0 masses are negligible.

The minimal GUT with inflaton and dark matter unification

Energy Technology Data Exchange (ETDEWEB)

Chen, Heng-Yu; Gogoladze, Ilia [University of Delaware, Department of Physics and Astronomy, Bartol Research Institute, Newark, DE (United States); Hu, Shan [Hubei University, Department of Physics, Faculty of Physics and Electronic Sciences, Wuhan (China); Li, Tianjun [Chinese Academy of Sciences, Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Beijing (China); University of Chinese Academy of Sciences, School of Physical Sciences, Beijing (China); Wu, Lina [Chinese Academy of Sciences, Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Beijing (China); University of Electronic Science and Technology of China, School of Physical Electronics, Chengdu (China)

2018-01-15

Giving up the solutions to the fine-tuning problems, we propose the non-supersymmetric flipped SU(5) x U(1){sub X} model based on the minimal particle content principle, which can be constructed from the four-dimensional SO(10) models, five-dimensional orbifold SO(10) models, and local F-theory SO(10) models. To achieve gauge coupling unification, we introduce one pair of vector-like fermions, which form a complete SU(5) x U(1){sub X} representation. The proton lifetime is around 5 x 10{sup 35} years, neutrino masses and mixing can be explained via the seesaw mechanism, baryon asymmetry can be generated via leptogenesis, and the vacuum stability problem can be solved as well. In particular, we propose that inflaton and dark matter particles can be unified to a real scalar field with Z{sub 2} symmetry, which is not an axion and does not have the non-minimal coupling to gravity. Such a kind of scenarios can be applied to the generic scalar dark matter models. Also, we find that the vector-like particle corrections to the B{sub s}{sup 0} masses might be about 6.6%, while their corrections to the K{sup 0} and B{sub d}{sup 0} masses are negligible. (orig.)

The OSp(32 vertical stroke 1) versus OSp(8 vertical stroke 2) supersymmetric M-brane action from self-dual (2,2) strings

International Nuclear Information System (INIS)

Ketov, S.V.

1996-09-01

Taking the (2,2) strings as a starting point, we discuss the equivalent self-dual field theories and analyze their symmetry structure in 2+2 dimensions from the viewpoint of string/membrane unification. Requiring the 'Lorentz' invariance and supersymmetry in the (2,2) string target space leads to an extension of the (2,2) string theory to a theory of 2+2 dimensional supermembranes (M-branes) propagating in a higher dimensional target space. The origin of the hidden target space dimensions of the M-brane is related to the maximally extended supersymmetry implied by the 'Lorentz' covariance and dimensional reasons. The Kaehler-Chern-Simons-type action describing the self-dual gravity in 2+2 dimensions is proposed. Its maximal supersymmetrization (of the Green-Schwarz-type) naturally leads to the 2+10 (or higher) dimensions for the M-brane target space. The proposed OSp(32 vertical stroke 1) supersymmetric action gives the pre-geometrical description of M-branes, which may be useful for a fundamental formulation of F and M theory. (orig.)

Supersymmetric particles at LEP

International Nuclear Information System (INIS)

Barbiellini, G.; Coignet, G.; Gaillard, M.K.; Bonneaud, G.; Ellis, J.; Matteuzzi, C.; Wiik, H.

1979-10-01

The authors examine whether the supersymmetrization of nature at a mass scale up to 100 GeV can be confirmed or excluded by experiments with LEP. They review the qualitative features of the spectroscopy suggested by supersymmetric theories. Then they discuss possible production rates and means of detection of these particles at LEP. In this framework they make some remarks about other projects for future high energy physics machines which can be used for the study of supersymmetric phenomena. (HSI)

N-anti N oscillation in SO(10) and SU(6) supersymmetric grand unified models

International Nuclear Information System (INIS)

Fujimoto, Y.; Zhiyong, Z.

1982-06-01

N-anti N oscillation in SO(10) and SU(6) S.G.U.M. is considered. We find a new type of diagram leading to a faster oscillation rate than in non-supersymmetric case. It is also noted that in SO(10) S.G.U.M. with intermediate SU(4)sub(C)xSU(2)sub(L)xSU(2)sub(R) symmetry N-anti N oscillation would be highly suppressed, which may not necessarily be the case for SU(6) S.G.U.M. (author)

Supersymmetric models without R parity

International Nuclear Information System (INIS)

Ross, G.G.; Valle, J.W.F.

1985-01-01

We show that many supersymmetric models may spontaneously break R parity through scalar neutrinos acquiring a vacuum expectation value (vev). These models allow supersymmetric particles to be produced singly and to decay to nonsupersymmetric states. This leads to a new pattern of supersymmetric phenomenology. We discuss the lepton number violation to be expected in this class of models. (orig.)

Supersymmetric extensions of K field theories

Science.gov (United States)

Adam, C.; Queiruga, J. M.; Sanchez-Guillen, J.; Wereszczynski, A.

2012-02-01

We review the recently developed supersymmetric extensions of field theories with non-standard kinetic terms (so-called K field theories) in two an three dimensions. Further, we study the issue of topological defect formation in these supersymmetric theories. Specifically, we find supersymmetric K field theories which support topological kinks in 1+1 dimensions as well as supersymmetric extensions of the baby Skyrme model for arbitrary nonnegative potentials in 2+1 dimensions.

Psychotherapy Integration via Theoretical Unification

Directory of Open Access Journals (Sweden)

Warren W. Tryon

2017-01-01

Full Text Available Meaningful psychotherapy integration requires theoretical unification because psychotherapists can only be expected to treat patients with the same diagnoses similarly if they understand these disorders similarly and if they agree on the mechanisms by which effective treatments work. Tryon (in press has proposed a transtheoretic transdiagnostic psychotherapy based on an Applied Psychological Science (APS clinical orientation, founded on a BioPsychology Network explanatory system that provides sufficient theoretical unification to support meaningful psychotherapy integration. That proposal focused mainly on making a neuroscience argument. This article makes a different argument for theoretical unification and consequently psychotherapy integration. The strength of theories of psychotherapy, like all theory, is to focus on certain topics, goals, and methods. But this strength is also a weakness because it can blind one to alternative perspectives and thereby promote unnecessary competition among therapies. This article provides a broader perspective based on learning and memory that is consistent with the behavioral, cognitive, cognitive-behavioral, psychodynamic, pharmacologic, and Existential/Humanistic/Experiential clinical orientations. It thereby provides a basis for meaningful psychotherapy integration.

New supersymmetrizations of the generalized KDV hierarchies

International Nuclear Information System (INIS)

Figueroa-O'Farrill, J.M.; Stanciu, S.

1993-03-01

Recently we investigated a new supersymmetrization procedure for the KdV hierarchy inspired in some recent work on supersymmetric matrix models. We extend this procedure here for the generalized KdV hierarchies. The resulting supersymmetric hierarchies are generically nonlocal, expect for the case of Boussinesque which we treat in detail. The resulting supersymmetric hierarchy is integrable and bihamiltonian and contains the Boussinesque hierarchy as a subhierarchy. In a particular realization, we extend it by defining supersymmetric odd flows. We end with some comments on a slight modification of this supersymmetrization which yields local equations for any generalized KdV hierarchy. (orig.)

SU(5) unification with TeV-scale leptoquarks

Energy Technology Data Exchange (ETDEWEB)

Cox, Peter [Kavli Institute for the Physics and Mathematics of the Universe (WPI), UTIAS,The University of Tokyo, Kashiwa, Chiba, 277-8583 (Japan); Kusenko, Alexander [Department of Physics and Astronomy, University of California,Los Angeles, CA, 90095-1547 (United States); Kavli Institute for the Physics and Mathematics of the Universe (WPI), UTIAS,The University of Tokyo, Kashiwa, Chiba, 277-8583 (Japan); Sumensari, Olcyr [Laboratoire de Physique Théorique, CNRS, Université Paris-Sud, Université Paris-Saclay,Orsay, 91405 (France); Instituto de Física, Universidade de São Paulo,C.P. 66.318, São Paulo, 05315-970 (Brazil); Yanagida, Tsutomu T. [Kavli Institute for the Physics and Mathematics of the Universe (WPI), UTIAS,The University of Tokyo, Kashiwa, Chiba, 277-8583 (Japan)

2017-03-07

It was previously noted that SU(5) unification can be achieved via the simple addition of light scalar leptoquarks from two split 10 multiplets. We explore the parameter space of this model in detail and find that unification requires at least one leptoquark to have mass below ≈16 TeV. We point out that introducing splitting of the 24 allows the unification scale to be raised beyond 10{sup 16} GeV, while a U(1){sub PQ} symmetry can be imposed to forbid dangerous proton decay mediated by the light leptoquarks. The latest bounds from LHC searches are combined and we find that a leptoquark as light as 400 GeV is still permitted. Finally, we discuss the interesting possibility that the leptoquarks required for unification could also be responsible for the 2.6σ deviation observed in the ratio R{sub K} at LHCb.

The economic implications of Korean unification

OpenAIRE

Schmitz, Jonathan L.

2002-01-01

Approved for public release; distribution unlimited A major area of concern for Korean unification is the immense cost it will impose on South Korea. To lessen this burden, South Korea will need to initiate policy reforms that can ease the financial stress and repercussions of unification and create an integrated economic community with North Korea. At the same time, North Korea will need to create an environment that is conducive to economic integration by accepting and adopting reform me...

Supersymmetric quantum mechanics on n-dimensional manifolds

International Nuclear Information System (INIS)

O'Connor, M.

1990-01-01

In this thesis the author investigates the properties of the supersymmetric path integral on Riemannian manifolds. Chapter 1 is a brief introduction to supersymmetric path integral can be defined as the continuum limit of a discrete supersymmetric path integral. In Chapter 3 he shows that point canonical transformations in the path integral for ordinary quantum mechanics can be performed naively provided one uses the supersymmetric path integral. Chapter 4 generalizes the results of chapter 3 to include the propagation of all the fermion sectors in supersymmetric quantum mechanics. In Chapter 5 he shows how the properties of supersymmetric quantum mechanics can be used to investigate topological quantum mechanics

Structural convergence under reversible and irreversible monetary unification

NARCIS (Netherlands)

Beetsma, R.M.W.J.; Jensen, H.

2003-01-01

We explore endogenous monetary unification in the context of a model in which a country with serious structural distortions (and, hence, high inflation) is admitted into a monetary union once its economic structure has converged sufficiently towards that of the existing participants. If unification

Structural convergence under reversible and irreversible monetary unification

NARCIS (Netherlands)

Beetsma, R.M.W.J.; Jensen, H.

1999-01-01

We explore endogenous monetary unification in the context of a model in which a country with serious structural distortions (and, hence, high inflation) is admitted into a monetary union once its economic structure has converged sufficiently towards that of the existing participants. If unification

Predictions of the Higgs mass and the weak mixing angle in the 6D gauge-Higgs unification

International Nuclear Information System (INIS)

Hasegawa, Kouhei; Lim, Chong-Sa; Maru, Nobuhito

2016-01-01

In the gauge-Higgs unification with multiple extra spaces, the Higgs self-coupling is on the order of g 2 and the Higgs boson is predicted to be light, being consistent with the LHC results. When the gauge group is simple, the weak mixing angle is also predictable. We address a question on whether there exists a model of gauge-Higgs unification in six-dimensional space-time, which successfully predicts the mass ratios of the Higgs boson and weak gauge bosons. First, using a useful formula, we give a general argument on the condition for obtaining a realistic prediction of the weak mixing angle sin 2 θ W = 1/4, and find that triplet and sextet representations of the minimal SU(3) gauge group lead to the realistic prediction. Concerning the Higgs mass, we notice that, in the models with one Higgs doublet, the predicted Higgs mass is always the same: M H = 2M W . However, by extending our discussion to the models with two Higgs doublets, the situation changes: we obtain an interesting prediction M H ≤ 2M W at the leading order of the perturbation. Thus, it is possible to recover the observed Higgs mass, 125 GeV, for a suitable choice of the parameter. The situation is in clear contrast to the case of the minimal supersymmetric standard model, where M H ≤ M Z at the classical level and the predicted Higgs mass cannot recover the observed value. (author)

Vanishing corrections on intermediate scale and implications for unification of forces

International Nuclear Information System (INIS)

Parida, M.K.

1996-02-01

In two-step breakings of a class of grand unified theories including SO(10), we prove a theorem showing that the scale (M I ) where the Pati-Salam gauge symmetry with parity breaks down to the standard gauge group, has vanishing corrections due to all sources emerging from higher scales (μ > M I ) such as the one-loop and all higher-loop effects, the GUT-threshold, gravitational smearing, and string threshold effects. Implications of such a scale for the unification of gauge couplings with small Majorana neutrino masses are discussed. In string inspired SO(10), we show that M I ≅ 5 x 10 12 GeV, needed for neutrino masses, with the GUT scale M U ≅ M str can be realized provided certain particle states in the predicted spectrum are light. (author). 28 refs, 1 tab

Hidden SUSY from precision gauge unification

Energy Technology Data Exchange (ETDEWEB)

Krippendorf, Sven; Nilles, Hans Peter [Bonn Univ. (Germany). Bethe Center for Theoretical Physics; Bonn Univ. (Germany). Physikalisches Inst.; Ratz, Michael [Technische Univ. Muenchen, Garching (Germany). Physik-Department; Winkler, Martin Wolfgang [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

2013-06-15

We revisit the implications of naturalness and gauge unification in the MSSM. We find that precision unification of the couplings in connection with a small {mu} parameter requires a highly compressed gaugino pattern as it is realized in mirage mediation. Due to the small mass difference between gluino and LSP, collider limits on the gluino mass are drastically relaxed. Without further assumptions, the relic density of the LSP is very close to the observed dark matter density due to coannihilation effects.

Hidden SUSY from precision gauge unification

International Nuclear Information System (INIS)

Krippendorf, Sven; Nilles, Hans Peter

2013-06-01

We revisit the implications of naturalness and gauge unification in the MSSM. We find that precision unification of the couplings in connection with a small μ parameter requires a highly compressed gaugino pattern as it is realized in mirage mediation. Due to the small mass difference between gluino and LSP, collider limits on the gluino mass are drastically relaxed. Without further assumptions, the relic density of the LSP is very close to the observed dark matter density due to coannihilation effects.

Supersymmetric and non-supersymmetric models without catastrophic Goldstone bosons

Energy Technology Data Exchange (ETDEWEB)

Braathen, Johannes; Goodsell, Mark D. [LPTHE, UPMC Univ. Paris 6, Sorbonne Universites, Paris (France); LPTHE, CNRS, Paris (France); Staub, Florian [Karlsruhe Institute of Technology, Institute for Theoretical Physics (ITP), Karlsruhe (Germany); Karlsruhe Institute of Technology, Institute for Nuclear Physics (IKP), Eggenstein-Leopoldshafen (Germany)

2017-11-15

The calculation of the Higgs mass in general renormalisable field theories has been plagued by the so-called ''Goldstone Boson Catastrophe'', where light (would-be) Goldstone bosons give infra-red divergent loop integrals. In supersymmetric models, previous approaches included a workaround that ameliorated the problem for most, but not all, parameter space regions; while giving divergent results everywhere for non-supersymmetric models. We present an implementation of a general solution to the problem in the public code SARAH, along with new calculations of some necessary loop integrals and generic expressions. We discuss the validation of our code in the Standard Model, where we find remarkable agreement with the known results. We then show new applications in Split SUSY, the NMSSM, the Two-Higgs-Doublet Model, and the Georgi-Machacek model. In particular, we take some first steps to exploring where the habit of using tree-level mass relations in non-supersymmetric models breaks down, and show that the loop corrections usually become very large well before naive perturbativity bounds are reached. (orig.)

Dark matter from unification

DEFF Research Database (Denmark)

Kainulainen, Kimmo; Tuominen, Kimmo; Virkajärvi, Jussi Tuomas

2013-01-01

We consider a minimal extension of the Standard Model (SM), which leads to unification of the SM coupling constants, breaks electroweak symmetry dynamically by a new strongly coupled sector and leads to novel dark matter candidates. In this model, the coupling constant unification requires...... eigenstates of this sector and determine the resulting relic density. The results are constrained by available data from colliders and direct and indirect dark matter experiments. We find the model viable and outline briefly future research directions....... the existence of electroweak triplet and doublet fermions singlet under QCD and new strong dynamics underlying the Higgs sector. Among these new matter fields and a new right handed neutrino, we consider the mass and mixing patterns of the neutral states. We argue for a symmetry stabilizing the lightest mass...

Collisional processes in supersymmetric plasma

International Nuclear Information System (INIS)

Czajka, Alina; Mrowczynski, Stanislaw

2011-01-01

Collisional processes in ultrarelativistic N=1 supersymmetric QED plasma are studied and compared to those in an electromagnetic plasma of electrons, positrons and photons. Cross sections of all binary interactions which occur in the supersymmetric plasma at the order of e 4 are computed. Some processes, in particular, the Compton scattering on selectrons, appear to be independent of momentum transfer and thus they are qualitatively different from processes in an electromagnetic plasma. It suggests that the transport properties of the supersymmetric plasma are different than those of its nonsupersymmetric counterpart. Energy loss and momentum broadening of a particle traversing the supersymmetric plasma are discussed in detail and the characteristics are shown to be surprisingly similar to those of QED plasma.

Simple unification

International Nuclear Information System (INIS)

Ponce, W.A.; Zepeda, A.

1987-08-01

We present the results obtained from our systematic search of a simple Lie group that unifies weak and electromagnetic interactions in a single truly unified theory. We work with fractionally charged quarks, and allow for particles and antiparticles to belong to the same irreducible representation. We found that models based on SU(6), SU(7), SU(8) and SU(10) are viable candidates for simple unification. (author). 23 refs

Proton decay in a nucleus: Nonrelativistic treatment of nuclear effects

International Nuclear Information System (INIS)

Fernandez, L.A.; Alvarez-Estrada, R.F.; Sanchez-Gomez, J.L.

1983-01-01

In this paper, proton decay in a large nucleus is studied in the framework of SU(5) grand unification theory (GUT). By using a method based upon the Green's-function technique of many-body physics, nuclear effects on spectator and pole terms are computed. The decay width in the nucleus is found to be practically the same as in free space. However, nuclear effects are of considerable importance concerning the positron spectrum. A density-correlation expansion is introduced which is useful for carrying out a systematic study of nuclear effects in proton decay in a large nucleus. The method presented here can be easily extended to other GUT's or supersymmetric GUT's

Experimental prospects for SUSY in e+e-

International Nuclear Information System (INIS)

Settles, R.

1995-01-01

Hopes for detecting supersymmetry in e + e - annihilations are reviewed using examples from several workshops on present and future colliders. MSSM, the simplest model of minimal supersymmetry with grand unification is studied. Chances for discovering the higgs sector at LEP and at a future 500 GeV e + e - linear collider are cited along with ways for measuring the higgs' properties; similary for the supersymmetric partners of the presently-known elementary particles. Once discovered, examples are given as to how to attack the spartner spectroscopy and MSSM parameters at the e + e - linear collider. The complementarity of these measurements to those at pp colliders is emphasized. (orig.)

Precision Experiments at LEP

CERN Document Server

de Boer, Wim

2015-01-01

The Large Electron Positron Collider (LEP) established the Standard Model (SM) of particle physics with unprecedented precision, including all its radiative corrections. These led to predictions for the masses of the top quark and Higgs boson, which were beautifully confirmed later on. After these precision measurements the Nobel Prize in Physics was awarded in 1999 jointly to 't Hooft and Veltman "for elucidating the quantum structure of electroweak interactions in physics". Another hallmark of the LEP results were the precise measurements of the gauge coupling constants, which excluded unification of the forces within the SM, but allowed unification within the supersymmetric extension of the SM. This increased the interest in Supersymmetry (SUSY) and Grand Unified Theories, especially since the SM has no candidate for the elusive dark matter, while Supersymmetry provides an excellent candidate for dark matter. In addition, Supersymmetry removes the quadratic divergencies of the SM and {\\it predicts} the Hig...

Duality in supersymmetric Yang-Mills theory

International Nuclear Information System (INIS)

Peskin, M.E.

1997-02-01

These lectures provide an introduction to the behavior of strongly-coupled supersymmetric gauge theories. After a discussion of the effective Lagrangian in nonsupersymmetric and supersymmetric field theories, the author analyzes the qualitative behavior of the simplest illustrative models. These include supersymmetric QCD for N f c , in which the superpotential is generated nonperturbatively, N = 2 SU(2) Yang-Mills theory (the Seiberg-Witten model), in which the nonperturbative behavior of the effect coupling is described geometrically, and supersymmetric QCD for N f large, in which the theory illustrates a non-Abelian generalization of electric-magnetic duality. 75 refs., 12 figs

The massless limit of supersymmetric QCD

International Nuclear Information System (INIS)

Davis, A.C.; Dine, M.; Seiberg, N.

1983-01-01

We construct an effective lagrangian for supersymmetric QCD, using a simple set of rules. The model with non-zero quark mass, msub(q), has at least N supersymmetric vacua, where N is the number of colors (in agreement with Witten's index). These vacua move to infinity as msub(q)->0. We study the possibility of supersymmetric breaking at msub(q)=0. (orig.)

Duality in supersymmetric Yang-Mills theory

Energy Technology Data Exchange (ETDEWEB)

Peskin, M.E.

1997-02-01

These lectures provide an introduction to the behavior of strongly-coupled supersymmetric gauge theories. After a discussion of the effective Lagrangian in nonsupersymmetric and supersymmetric field theories, the author analyzes the qualitative behavior of the simplest illustrative models. These include supersymmetric QCD for N{sub f} < N{sub c}, in which the superpotential is generated nonperturbatively, N = 2 SU(2) Yang-Mills theory (the Seiberg-Witten model), in which the nonperturbative behavior of the effect coupling is described geometrically, and supersymmetric QCD for N{sub f} large, in which the theory illustrates a non-Abelian generalization of electric-magnetic duality. 75 refs., 12 figs.

Pseudo-Goldstone Higgs Doublets from Non-Vectorlike Grand Unified Higgs Sector

CERN Document Server

Hernández, A E Cárcamo

2016-01-01

We present a novel way of realizing the pseudo-Nambu-Goldstone boson mechanism for the doublet-triplet splitting in supersymmetric grand unified theories. The global symmetries of the Higgs sector are attributed to a non-vectorlike Higgs content, which is consistent with unbroken supersymmetry in a scenario with flat extra dimensions and branes. We also show how in such a model one can naturally obtain a realistic pattern for the Standard Model fermion masses and mixings.

Dirac gauginos, gauge mediation and unification

Energy Technology Data Exchange (ETDEWEB)

Benakli, K. [UPMC Univ. Paris 06 (France). Laboratoire de Physique Theorique et Hautes Energies, CNRS; Goodsell, M.D. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

2010-03-15

We investigate the building of models with Dirac gauginos and perturbative gauge coupling unification. Here, in contrast to the MSSM, additional fields are required for unification, and these can naturally play the role of the messengers of supersymmetry breaking. We present a framework within which such models can be constructed, including the constraints that the messenger sector must satisfy; and the renormalisation group equations for the soft parameters, which differ from those of the MSSM. For illustration, we provide the spectrum at the electroweak scale for explicit models whose gauge couplings unify at the scale predicted by heterotic strings. (orig.)

Dirac Gauginos, Gauge Mediation and Unification

CERN Document Server

Benakli, K

2010-01-01

We investigate the building of models with Dirac gauginos and perturbative gauge coupling unification. Here, in contrast to the MSSM, additional fields are required for unification, and these can naturally play the role of the messengers of supersymmetry breaking. We present a framework within which such models can be constructed, including the constraints that the messenger sector must satisfy; and the renormalisation group equations for the soft parameters, which differ from those of the MSSM. For illustration, we provide the spectrum at the electroweak scale for explicit models whose gauge couplings unify at the scale predicted by heterotic strings.

Dirac gauginos, gauge mediation and unification

International Nuclear Information System (INIS)

Benakli, K.

2010-03-01

We investigate the building of models with Dirac gauginos and perturbative gauge coupling unification. Here, in contrast to the MSSM, additional fields are required for unification, and these can naturally play the role of the messengers of supersymmetry breaking. We present a framework within which such models can be constructed, including the constraints that the messenger sector must satisfy; and the renormalisation group equations for the soft parameters, which differ from those of the MSSM. For illustration, we provide the spectrum at the electroweak scale for explicit models whose gauge couplings unify at the scale predicted by heterotic strings. (orig.)

China’s unification: Myth or reality?

Directory of Open Access Journals (Sweden)

Estrada Mario Arturo Ruiz

2014-01-01

Full Text Available This paper evaluates the prospect of a possible unification between People’s Republic of China (Mainland China and Republic of China (Taiwan from a multi-dimensional perspective which encompasses the political, social, economic, and technological dimensions. The underlying idea is to evaluate the possibility of a partial or total reunification between the two countries in a more comprehensive way than just assessing the economic costs and benefits. Our evaluation is based on the application of the GDRI-Model, which looks at unification and regional integration simultaneously from the political, economic, social and technological perspectives.

Supersymmetric Quantum Mechanics and Topology

International Nuclear Information System (INIS)

Wasay, Muhammad Abdul

2016-01-01

Supersymmetric quantum mechanical models are computed by the path integral approach. In the β→0 limit, the integrals localize to the zero modes. This allows us to perform the index computations exactly because of supersymmetric localization, and we will show how the geometry of target space enters the physics of sigma models resulting in the relationship between the supersymmetric model and the geometry of the target space in the form of topological invariants. Explicit computation details are given for the Euler characteristics of the target manifold and the index of Dirac operator for the model on a spin manifold.

Non-minimal supersymmetric models. LHC phenomenolgy and model discrimination

Energy Technology Data Exchange (ETDEWEB)

Krauss, Manuel Ernst

2015-12-18

It is generally agreed upon the fact that the Standard Model of particle physics can only be viewed as an effective theory that needs to be extended as it leaves some essential questions unanswered. The exact realization of the necessary extension is subject to discussion. Supersymmetry is among the most promising approaches to physics beyond the Standard Model as it can simultaneously solve the hierarchy problem and provide an explanation for the dark matter abundance in the universe. Despite further virtues like gauge coupling unification and radiative electroweak symmetry breaking, minimal supersymmetric models cannot be the ultimate answer to the open questions of the Standard Model as they still do not incorporate neutrino masses and are besides heavily constrained by LHC data. This does, however, not derogate the beauty of the concept of supersymmetry. It is therefore time to explore non-minimal supersymmetric models which are able to close these gaps, review their consistency, test them against experimental data and provide prospects for future experiments. The goal of this thesis is to contribute to this process by exploring an extraordinarily well motivated class of models which bases upon a left-right symmetric gauge group. While relaxing the tension with LHC data, those models automatically include the ingredients for neutrino masses. We start with a left-right supersymmetric model at the TeV scale in which scalar SU(2){sub R} triplets are responsible for the breaking of left-right symmetry as well as for the generation of neutrino masses. Although a tachyonic doubly-charged scalar is present at tree-level in this kind of models, we show by performing the first complete one-loop evaluation that it gains a real mass at the loop level. The constraints on the predicted additional charged gauge bosons are then evaluated using LHC data, and we find that we can explain small excesses in the data of which the current LHC run will reveal if they are actual new

Supersymmetric unification at the millennium

Indian Academy of Sciences (India)

charisma for the high energy theory community. Although .... universe from evaporation into radiation. ... theories: RФ is effectively a part of their gauge symmetry. ..... processes such as μ — e7 and electric dipole moments for the neutron.

Supersymmetric unification at the millennium

Indian Academy of Sciences (India)

charisma for the high energy theory community. ... bereft of a chiral partner, and its minimal mass operator – the d = 5 operator above ... Integrating out the heavy neutrino gives the neutrino mass operator .... (b) Stay with the minimal set of fields, but (reasoning that small non- .... My treatment is largely based on the excellent.

How to quantize supersymmetric theories

International Nuclear Information System (INIS)

Smilga, A.V.

1985-01-01

A recipe for resolving the ordering ambiguities in quantum hamiltonians of supersymmetric theories is suggested. The Weyl ordering procedure applied to classical supercharges expressed as functions on the phase space of a classically supersymmetric system is shown to result in quantum operators which satisfy usual SUSY algebra. The quantum hamiltonian does not always coincide with the Weyl ordered classical hamiltonian function. The difference is due to that the Weyl symbol of the supercharge anticommutator does not coincide with the Poisson bracket of their Weyl symbols (i.e. the classical hamiltonian). The procedure is applied to supersymmetric σ-models (both N=2 and N=1 cases are analyzed) and also to the supersymmetric SU(2) Yang-Mills theory. Only quantum mechanical systems following from field theories when fields are assumed to be independent of space coordinates are considered. For gauge theories thesuggested recipe for quantization leads to the same result as the well-known Dirac recipe

Supersymmetric two-particle equations

International Nuclear Information System (INIS)

Sissakyan, A.N.; Skachkov, N.B.; Shevchenko, O.Yu.

1986-01-01

In the framework of the scalar superfield model, a particular case of which is the well-known Wess-Zumino model, the supersymmetric Schwinger equations are found. On their basis with the use of the second Legendre transformation the two-particle supersymmetric Edwards and Bethe-Salpeter equations are derived. A connection of the kernels and inhomogeneous terms of these equations with generating functional of the second Legendre transformation is found

Unification of Patrimonial Laws Governing International Trade

DEFF Research Database (Denmark)

Lando, Ole

2016-01-01

Should the laws of the world dealing with cross-border transactions be unified? Such unification presupposes an agreement on what we understand by ‘law’ and what its sources are. The drafters of uniform laws and lawyers who are preoccupied with comparative law often ask themselves: Is there, among...... the nations, a common core of legal values? If there is, this will facilitate legal unification. It will also make the international law-making easier if, in exceptional cases, a court is permitted to disregard a legal rule....

Dark Matter in SuperGUT Unification Models

International Nuclear Information System (INIS)

Olive, Keith A

2011-01-01

After a brief update on the prospects for dark matter in the constrained version of the MSSM (CMSSM) and its differences with models based on minimal supergravity (mSUGRA), I will consider the effects of unifying the supersymmetry-breaking parameters at a scale above M GUT . One of the consequences of superGUT unification, is the ability to take vanishing scalar masses at the unification scale with a neutralino LSP dark matter candidate. This allows one to resurrect no-scale supergravity as a viable phenomenological model.

Supersymmetric lattices

International Nuclear Information System (INIS)

Catterall, Simon

2013-01-01

Discretization of supersymmetric theories is an old problem in lattice field theory. It has resisted solution until quite recently when new ideas drawn from orbifold constructions and topological field theory have been brought to bear on the question. The result has been the creation of a new class of lattice gauge theory in which the lattice action is invariant under one or more supersymmetries. The resultant theories are local and free of doublers and in the case of Yang-Mills theories also possess exact gauge invariance. In principle they form the basis for a truly non-perturbative definition of the continuum supersymmetric field theory. In this talk these ideas are reviewed with particular emphasis being placed on N = 4 super Yang-Mills theory.

Non-supersymmetric orientifolds of Gepner models

Energy Technology Data Exchange (ETDEWEB)

Gato-Rivera, B. [NIKHEF Theory Group, Kruislaan 409, 1098 SJ Amsterdam (Netherlands); Instituto de Fisica Fundamental, CSIC, Serrano 123, Madrid 28006 (Spain); Schellekens, A.N. [NIKHEF Theory Group, Kruislaan 409, 1098 SJ Amsterdam (Netherlands); Instituto de Fisica Fundamental, CSIC, Serrano 123, Madrid 28006 (Spain); IMAPP, Radboud Universiteit, Nijmegen (Netherlands)], E-mail: t58@nikhef.nl

2009-01-12

Starting from a previously collected set of tachyon-free closed strings, we search for N=2 minimal model orientifold spectra which contain the standard model and are free of tachyons and tadpoles at lowest order. For each class of tachyon-free closed strings - bulk supersymmetry, automorphism invariants or Klein bottle projection - we do indeed find non-supersymmetric and tachyon free chiral brane configurations that contain the standard model. However, a tadpole-cancelling hidden sector could only be found in the case of bulk supersymmetry. Although about half of the examples we have found make use of branes that break the bulk space-time supersymmetry, the resulting massless open string spectra are nevertheless supersymmetric in all cases. Dropping the requirement that the standard model be contained in the spectrum, we find chiral tachyon and tadpole-free solutions in all three cases, although in the case of bulk supersymmetry all massless spectra are supersymmetric. In the other two cases we find truly non-supersymmetric spectra, but a large fraction of them are nevertheless partly or fully supersymmetric at the massless level.

An Ordering Linear Unification Algorithm

Institute of Scientific and Technical Information of China (English)

胡运发

1989-01-01

In this paper,we present an ordering linear unification algorithm(OLU).A new idea on substituteion of the binding terms is introduced to the algorithm,which is able to overcome some drawbacks of other algorithms,e.g.,MM algorithm[1],RG1 and RG2 algorithms[2],Particularly,if we use the directed eyclie graphs,the algoritm needs not check the binding order,then the OLU algorithm can also be aplied to the infinite tree data struceture,and a higher efficiency can be expected.The paper focuses upon the discussion of OLU algorithm and a partial order structure with respect to the unification algorithm.This algorithm has been implemented in the GKD-PROLOG/VAX 780 interpreting system.Experimental results have shown that the algorithm is very simple and efficient.

Possible test of grand unification in the double beta-decay

International Nuclear Information System (INIS)

Faessler, A.

1988-01-01

The more successful grand unified theories predict that the neutrino is identical with its antiparticle and therefore is a Majorana neutrino which violates lepton number conservation. Such a neutrino should have a finite mass and also a small right handed weak interaction. If the double neutrinoless beta decay is observed with the full decay energy in the two electrons, it would establish that the electron neutrino is a Majorana particle. It is shown that the relativistic corrections of the nucleonic wave functions are essential for determining an upper limit of the right handedness from the measured lower limit of the life-time against the neutrinoless double beta decay. The upper limit for the right handedness of the weak interaction derived from the lower limit of the life-times against the neutrinoless beta decay is vertical stroke vertical stroke -8 and the upper limit for the neutrino mass is vertical stroke ν m>vertical stroke + -decay in proton rich nuclei, one can explain the long standing puzzle of the quenching of the Gamow-Teller strength in agreement with the data. (orig.)

Chaos and random matrices in supersymmetric SYK

Science.gov (United States)

Hunter-Jones, Nicholas; Liu, Junyu

2018-05-01

We use random matrix theory to explore late-time chaos in supersymmetric quantum mechanical systems. Motivated by the recent study of supersymmetric SYK models and their random matrix classification, we consider the Wishart-Laguerre unitary ensemble and compute the spectral form factors and frame potentials to quantify chaos and randomness. Compared to the Gaussian ensembles, we observe the absence of a dip regime in the form factor and a slower approach to Haar-random dynamics. We find agreement between our random matrix analysis and predictions from the supersymmetric SYK model, and discuss the implications for supersymmetric chaotic systems.

Einstein's dream : the space-time unification of fundamental forces

Energy Technology Data Exchange (ETDEWEB)

Salam, A [International Centre for Theoretical Physics, Trieste (Italy)

1981-06-01

The historical developments in physics which started with Galileo in the 11th century, Newton in the 17 century, culminated in the unification of space-time by Einstein in this century are traced. The theories put forward by Einstein himself and by subsequent workers in the field after him, regarding the unification of all basic forces of nature (i.e.) the electromagnetic and the gravitational ones and the weak and strong nuclear forces are discussed. The experiments being conducted in Kolar and other places to detect a heavier photon which would be a positive proof of the validity of the unification theory, are touched upon. The possible application of this concept even in industry has been pointed out.

Unification and geometrization of physics in the cosmological context

International Nuclear Information System (INIS)

Heller, M.; Watykanskie Obserwatorium Astronomiczne, Vatican

1991-01-01

Einstein belived that a good physical theory should posses an ''inner perfection''. Trace the inner perfection of the present gauge theories by contemplating their geometric structures (in terms of fibre bundles). The search for the ultimate symmetry of the unification of physics unavoidably leads to the unification of physics and cosmology. 4 figs., 23 refs. (author)

The supersymmetric Pegg-Barnett oscillator

International Nuclear Information System (INIS)

Shen, Jian Qi

2005-01-01

The su(n) Lie algebraic structure of the Pegg-Barnett oscillator that possesses a finite-dimensional number-state space is demonstrated. The supersymmetric generalization of the Pegg-Barnett oscillator is suggested. it is shown that such a supersymmetric Pegg-Barnett oscillator may have some potential applications, e.g., the mass spectrum of the charged leptons

Strings: A possible alternative explanation for the Unification of Gravitation Field and Electromagnetic Field

Science.gov (United States)

Rivera, Susana

Throughout the last century, since the last decades of the XIX century, until present day, there had been many attempts to achieve the unification of the Forces of Nature. First unification was done by James Clerk Maxwell, with his Electromagnetic Theory. Then Max Plank developed his Quantum Theory. In 1905, Albert Einstein gave birth to the Special Relativity Theory, and in 1916 he came out with his General Relativity Theory. He noticed that there was an evident parallelism between the Gravitational Force, and the Electromagnetic Force. So, he tried to unify these forces of Nature. But Quantum Theory interposed on his way. On the 1940’s it had been developed the Quantum Electrodynamics (QED), and with it, the unified field theory had an arise interest. On the 60’s and 70’s there was developed the Quantum Chromodynamics (QCD). Along with these theories came the discovery of the strong interaction force and weak interaction force. And though there had been many attempts to unify all these forces of the nature, it could only be achieved the Unification of strong interaction, weak interaction and Electromagnetic Force. On the late 80”s and throughout the last two decades, theories such as “super-string theory”, “or the “M-theory”, among others, groups of Scientists, had been doing grand efforts and finally they came out with the unification of the forces of nature, being the only limitation the use of more than 11 dimensions. Using an ingenious mathematical tool known as the super symmetries, based on the Kaluza - Klein work, they achieve this goal. The strings of these theories are in the rank of 10-33 m. Which make them undetectable. There are many other string theories. The GEUFT theory is based on the existence of concentrated energy lines, which vibrates, expands and contracts, submitting and absorbing energy, matter and antimatter, and which yields a determined geometry, that gives as a result the formation of stars, galaxies, nebulae, clusters

Ultraviolet divergences in non-renormalizable supersymmetric theories

International Nuclear Information System (INIS)

Smilga, A.

2017-01-01

We present a pedagogical review of our current understanding of the ultraviolet structure of N =(1, 1) 6D supersymmetric Yang-Mills theory and of N = 8 4D supergravity. These theories are not renormalizable, they involve power ultraviolet divergences and, in all probability, an infinite set of higher-dimensional counterterms that contribute to on-mass-shell scattering amplitudes. A specific feature of supersymmetric theories (especially of extended supersymmetric theories) is that these counterterms may not be invariant off-shell under the full set of supersymmetry transformations. The lowest-dimensional nontrivial counterterm is supersymmetric on-shell. Still higher counterterms may lose even the on-shell invariance. On the other hand, the full effective Lagrangian, generating the amplitudes and representing an infinite sum of counterterms, still enjoys the complete symmetry of original theory. We also discuss simple supersymmetric quantum-mechanical models that exhibit the same behavior.

Renormalization of supersymmetric theories

International Nuclear Information System (INIS)

Pierce, D.M.

1998-06-01

The author reviews the renormalization of the electroweak sector of the standard model. The derivation also applies to the minimal supersymmetric standard model. He discusses regularization, and the relation between the threshold corrections and the renormalization group equations. He considers the corrections to many precision observables, including M W and sin 2 θ eff . He shows that global fits to the data exclude regions of supersymmetric model parameter space and lead to lower bounds on superpartner masses

Supersymmetric gauge field theories

International Nuclear Information System (INIS)

Slavnov, A.A.

1976-01-01

The paper is dealing with the role of supersymmetric gauge theories in the quantum field theory. Methods of manipulating the theories as well as possibilities of their application in elementary particle physics are presented. In particular, the necessity is explained of a theory in which there is symmetry between Fermi and Bose fields, in other words, of the supersymmetric gauge theory for construction of a scheme for the Higgs particle connecting parameters of scalar mesons with those of the rest fields. The mechanism of supersymmetry breaking is discussed which makes it possible to remain the symmetric procedure of renormalization intact. The above mechanism of spontaneous symmetry breaking is applied to demonstrate possibilities of constructing models of weak and electromagnetic interactions which would be acceptable from the point of view of experiments. It is noted that the supersymmetric gauge theories represent a natural technique for description of vector-like models

Bubbles of nothing and supersymmetric compactifications

Energy Technology Data Exchange (ETDEWEB)

Blanco-Pillado, Jose J. [IKERBASQUE, Basque Foundation for Science, 48011, Bilbao (Spain); Department of Theoretical Physics, University of the Basque Country UPV/EHU,48080 Bilbao (Spain); Shlaer, Benjamin [Department of Physics, University of Auckland,Private Bag 92019, Auckland (New Zealand); Institute of Cosmology, Department of Physics and Astronomy,Tufts University, Medford, MA 02155 (United States); Sousa, Kepa [Department of Theoretical Physics, University of the Basque Country UPV/EHU,48080 Bilbao (Spain); Instituto de Fisica Teorica UAM-CSIC, Universidad Autonoma de Madrid,Cantoblanco, 28049 Madrid (Spain); Urrestilla, Jon [Department of Theoretical Physics, University of the Basque Country UPV/EHU,48080 Bilbao (Spain)

2016-10-03

We investigate the non-perturbative stability of supersymmetric compactifications with respect to decay via a bubble of nothing. We show examples where this kind of instability is not prohibited by the spin structure, i.e., periodicity of fermions about the extra dimension. However, such “topologically unobstructed” cases do exhibit an extra-dimensional analog of the well-known Coleman-De Luccia suppression mechanism, which prohibits the decay of supersymmetric vacua. We demonstrate this explicitly in a four dimensional Abelian-Higgs toy model coupled to supergravity. The compactification of this model to M{sub 3}×S{sub 1} presents the possibility of vacua with different windings for the scalar field. Away from the supersymmetric limit, these states decay by the formation of a bubble of nothing, dressed with an Abelian-Higgs vortex. We show how, as one approaches the supersymmetric limit, the circumference of the topologically unobstructed bubble becomes infinite, thereby preventing the realization of this decay. This demonstrates the dynamical origin of the decay suppression, as opposed to the more familiar argument based on the spin structure. We conjecture that this is a generic mechanism that enforces stability of any topologically unobstructed supersymmetric compactification.

(Non-)decoupled supersymmetric field theories

International Nuclear Information System (INIS)

Pietro, Lorenzo Di; Dine, Michael; Komargodski, Zohar

2014-01-01

We study some consequences of coupling supersymmetric theories to (super)gravity. To linear order, the couplings are determined by the energy-momentum supermultiplet. At higher orders, the couplings are determined by contact terms in correlation functions of the energy-momentum supermultiplet. We focus on the couplings of one particular field in the supergravity multiplet, the auxiliary field M. We discuss its linear and quadratic (seagull) couplings in various supersymmetric theories. In analogy to the local renormalization group formalism (http://dx.doi.org/10.1016/0370-2693(89)90729-6; http://dx.doi.org/10.1016/0550-3213(90)90584-Z; http://dx.doi.org/10.1016/0550-3213(91)80030-P), we provide a prescription for how to fix the quadratic couplings. They generally arise at two-loops in perturbation theory. We check our prescription by explicitly computing these couplings in several examples such as mass-deformed N=4 and in the Coulomb phase of some theories. These couplings affect the Lagrangians of rigid supersymmetric theories in curved space. In addition, our analysis leads to a transparent derivation of the phenomenon known as Anomaly Mediation. In contrast to previous approaches, we obtain both the gaugino and scalar masses of Anomaly Mediation by relying just on classical, minimal supergravity and a manifestly local and supersymmetric Wilsonian point of view. Our discussion naturally incorporates the connection between Anomaly Mediation and supersymmetric AdS 4 Lagrangians. This note can be read without prior familiarity with Anomaly Mediated Supersymmetry Breaking (AMSB)

Problems in unification and supergravity

International Nuclear Information System (INIS)

Farrar, G.; Henyey, F.

1984-01-01

Problems in unification of the various gauge groups, quantum gravity, supersymmetry and supergravity, compact dimensions of space-time, and conditions at the beginning of the universe are discussed. Separate entries were prepared for the data base for the 15 papers presented

Prospects for further unification

International Nuclear Information System (INIS)

Ne'eman, Y.

1983-07-01

We review the unification of weak and electromagnetic interactions (QAD), the prevalent color gauge theory of the strong interactions (QCD) and attempts to embed both these theories in a further Unified Gauge Theory. We discuss the related advances in cosmology and touch upon other approaches to the understanding of particles and fields. 44 references

Classification of supersymmetric backgrounds of string theory

International Nuclear Information System (INIS)

Gran, U.; Gutowski, J.; Papadopoulos, G.; Roest, D.

2007-01-01

We review the recent progress made towards the classification of supersymmetric solutions in ten and eleven dimensions with emphasis on those of IIB supergravity. In particular, the spinorial geometry method is outlined and adapted to nearly maximally supersymmetric backgrounds. We then demonstrate its effectiveness by classifying the maximally supersymmetric IIB G-backgrounds and by showing that N=31 IIB solutions do not exist. (Abstract Copyright [2007], Wiley Periodicals, Inc.)

Non-renormalization theorems andN=2 supersymmetric backgrounds

International Nuclear Information System (INIS)

Butter, Daniel; Wit, Bernard de; Lodato, Ivano

2014-01-01

The conditions for fully supersymmetric backgrounds of general N = 2 locally supersymmetric theories are derived based on the off-shell superconformal multiplet calculus. This enables the derivation of a non-renormalization theorem for a large class of supersymmetric invariants with higher-derivative couplings. The theorem implies that the invariant and its first order variation must vanish in a fully supersymmetric background. The conjectured relation of one particular higher-derivative invariant with a specific five-dimensional invariant containing the mixed gauge-gravitational Chern-Simons term is confirmed

Rare B decays, rare τ decays, and grand unification

International Nuclear Information System (INIS)

Sher, M.; Yuan, Y.

1991-01-01

In multi-Higgs-boson extensions of the standard model, tree-level flavor-changing neutral currents exist naturally, unless suppressed by some symmetry. For a given rate, the exchanged scalar or pseudoscalar mass is very sensitive to the flavor-changing coupling between the first two generations. Since the Yukawa couplings of the first two generations are unknown and certainly very small, bounds which rely on some assumed value of this flavor-changing coupling are quite dubious. One might expect the size (and reliability) of the Yukawa couplings involving the third generation to be greater. In this paper, we consider processes involving τ's and B's, and determine the bounds on the flavor-changing couplings which involve third-generation fields. The strongest bound in the quark sector comes from B-bar B mixing and in the lepton sector, surprisingly, from μ→eγ. It is then noted that the flavor-changing couplings in the quark sector are related to those in the lepton sector in many grand unified theories, and one can ask whether an analysis of rare τ decays or rare B decays will provide the strongest constraints. We show that rare B decays provide the strongest bounds, and that no useful information can be obtained from rare τ decays. It is also noted that the most promising decay modes are B→Kμτ and B s →μτ, and we urge experimenters to look for rare decay modes of the B in which a τ is in the final state

Supersymmetric partition functions and the three-dimensional A-twist

Energy Technology Data Exchange (ETDEWEB)

Closset, Cyril [Theory Department, CERN,CH-1211, Geneva 23 (Switzerland); Kim, Heeyeon [Perimeter Institute for Theoretical Physics,31 Caroline Street North, Waterloo, N2L 2Y5, Ontario (Canada); Willett, Brian [Kavli Institute for Theoretical Physics, University of California,Santa Barbara, CA 93106 (United States)

2017-03-14

We study three-dimensional N=2 supersymmetric gauge theories on M{sub g,p}, an oriented circle bundle of degree p over a closed Riemann surface, Σ{sub g}. We compute the M{sub g,p} supersymmetric partition function and correlation functions of supersymmetric loop operators. This uncovers interesting relations between observables on manifolds of different topologies. In particular, the familiar supersymmetric partition function on the round S{sup 3} can be understood as the expectation value of a so-called “fibering operator” on S{sup 2}×S{sup 1} with a topological twist. More generally, we show that the 3d N=2 supersymmetric partition functions (and supersymmetric Wilson loop correlation functions) on M{sub g,p} are fully determined by the two-dimensional A-twisted topological field theory obtained by compactifying the 3d theory on a circle. We give two complementary derivations of the result. We also discuss applications to F-maximization and to three-dimensional supersymmetric dualities.

Supersymmetric flaxion

Science.gov (United States)

Ema, Yohei; Hagihara, Daisuke; Hamaguchi, Koichi; Moroi, Takeo; Nakayama, Kazunori

2018-04-01

Recently, a new minimal extension of the Standard Model has been proposed, where a spontaneously broken, flavor-dependent global U(1) symmetry is introduced. It not only explains the hierarchical flavor structure in the quark and lepton sector, but also solves the strong CP problem by identifying the Nambu-Goldstone boson as the QCD axion, which we call flaxion. In this work, we consider supersymmetric extensions of the flaxion scenario. We study the CP and flavor violations due to supersymmetric particles, the effects of R-parity violations, the cosmological gravitino and axino problems, and the cosmological evolution of the scalar partner of the flaxion, sflaxion. We also propose an attractor-like inflationary model where the flaxion multiplet contains the inflaton field, and show that a consistent cosmological scenario can be obtained, including inflation, leptogenesis, and dark matter.

Problems in unification and supergravity

Energy Technology Data Exchange (ETDEWEB)

Farrar, G.; Henyey, F. (eds.)

1984-01-01

Problems in unification of the various gauge groups, quantum gravity, supersymmetry and supergravity, compact dimensions of space-time, and conditions at the beginning of the universe are discussed. Separate entries were prepared for the data base for the 15 papers presented. (WHK)

Lattice formulations of supersymmetric gauge theories with matter fields

International Nuclear Information System (INIS)

Joseph, Anosh

2014-12-01

Certain classes of supersymmetric gauge theories, including the well known N=4 supersymmetric Yang-Mills theory, that takes part in the AdS/CFT correspondence, can be formulated on a Euclidean spacetime lattice using the techniques of exact lattice supersymmetry. Great ideas such as topological field theories, Dirac-Kaehler fermions, geometric discretization all come together to create supersymmetric lattice theories that are gauge-invariant, doubler free, local and exact supersymmetric. We discuss the recent lattice constructions of supersymmetric Yang-Mills theories in two and three dimensions coupled to matter fields in various representations of the color group.

(Non-)decoupled supersymmetric field theories

Energy Technology Data Exchange (ETDEWEB)

Pietro, Lorenzo Di [Department of Particle Physics and Astrophysics,Weizmann Institute of Science, Rehovot 76100 (Israel); Dine, Michael [Santa Cruz Institute for Particle Physics and Department of Physics,Santa Cruz CA 95064 (United States); Komargodski, Zohar [Department of Particle Physics and Astrophysics,Weizmann Institute of Science, Rehovot 76100 (Israel)

2014-04-10

We study some consequences of coupling supersymmetric theories to (super)gravity. To linear order, the couplings are determined by the energy-momentum supermultiplet. At higher orders, the couplings are determined by contact terms in correlation functions of the energy-momentum supermultiplet. We focus on the couplings of one particular field in the supergravity multiplet, the auxiliary field M. We discuss its linear and quadratic (seagull) couplings in various supersymmetric theories. In analogy to the local renormalization group formalism (http://dx.doi.org/10.1016/0370-2693(89)90729-6; http://dx.doi.org/10.1016/0550-3213(90)90584-Z; http://dx.doi.org/10.1016/0550-3213(91)80030-P), we provide a prescription for how to fix the quadratic couplings. They generally arise at two-loops in perturbation theory. We check our prescription by explicitly computing these couplings in several examples such as mass-deformed N=4 and in the Coulomb phase of some theories. These couplings affect the Lagrangians of rigid supersymmetric theories in curved space. In addition, our analysis leads to a transparent derivation of the phenomenon known as Anomaly Mediation. In contrast to previous approaches, we obtain both the gaugino and scalar masses of Anomaly Mediation by relying just on classical, minimal supergravity and a manifestly local and supersymmetric Wilsonian point of view. Our discussion naturally incorporates the connection between Anomaly Mediation and supersymmetric AdS{sub 4} Lagrangians. This note can be read without prior familiarity with Anomaly Mediated Supersymmetry Breaking (AMSB)

The Economic Implications of Korean Unification

National Research Council Canada - National Science Library

Schmitz, Jonathan

2002-01-01

.... To lessen this burden, South Korea will need to initiate policy reforms that can ease the financial stress and repercussions of unification and create an integrated economic community with North Korea...

Supersymmetric and non-supersymmetric Seiberg-like dualities for gauged Wess–Zumino–Witten theories, realised on branes

Directory of Open Access Journals (Sweden)

E. Ireson

2016-01-01

Full Text Available In this work we extend the results of previous derivations of Seiberg-like dualities (level-rank duality between gauged Wess–Zumino–Witten theories. The arguments in use to identify a potential dual for the supersymmetric WZW theory based on the coset U(N+MkU(Nk can be extended to be applied to a wider variety of gauge groups, notably USp(2N+2M2kUSp(2N2k and SO(2N+2M2kSO(2N2k, which will be dealt with briefly. Most interestingly, non-supersymmetric versions of the latter theories can also be shown to have duals in a similar fashion. These results are supported by several pieces of evidence, string phenomenological interpretations of Seiberg duality, even in non-supersymmetric backgrounds, are helpful to justify the formulation, then, from field theory, quantities such as central charges or Witten indices are shown to match exactly. The stability of these non-supersymmetric models is also discussed and shown to be consistent.

Supersymmetric technicolor

International Nuclear Information System (INIS)

Srednicki, M.

1981-01-01

I will discuss some work I recently completed with M. Dine and W. Fischler on supersymmetric technicolor. E. Witten and S. Dimopoulos and S. Raby have considered similar ideas. Our central idea is to combine supersymmetry and technicolor to produce a natural theory which is capable of reproducing all the known phenomenology of particle physics, especially the quark-lepton mass spectrum and the absence of flavor changing neutral currents. Supersymmetry allows us to introduce fundamental scalars which are naturally light. Some of these scalars play the role of Higgs fields, and give mass to quarks and leptons via ordinary Yukawa couplings (which are chosen so that we get the correct masses and mixing angles). The supersymmetric partners of all known particles turn out to be too heavy to have been observed in experiments to data; many of them, however, weigh less than 100 GeV

Analysis of Ward identities in supersymmetric Yang-Mills theory

Science.gov (United States)

Ali, Sajid; Bergner, Georg; Gerber, Henning; Montvay, Istvan; Münster, Gernot; Piemonte, Stefano; Scior, Philipp

2018-05-01

In numerical investigations of supersymmetric Yang-Mills theory on a lattice, the supersymmetric Ward identities are valuable for finding the critical value of the hopping parameter and for examining the size of supersymmetry breaking by the lattice discretisation. In this article we present an improved method for the numerical analysis of supersymmetric Ward identities, which takes into account the correlations between the various observables involved. We present the first complete analysis of supersymmetric Ward identities in N=1 supersymmetric Yang-Mills theory with gauge group SU(3). The results indicate that lattice artefacts scale to zero as O(a^2) towards the continuum limit in agreement with theoretical expectations.

Unification of gauge couplings in radiative neutrino mass models

DEFF Research Database (Denmark)

Hagedorn, Claudia; Ohlsson, Tommy; Riad, Stella

2016-01-01

masses at one-loop level and (III) models with particles in the adjoint representation of SU(3). In class (I), gauge couplings unify in a few models and adding dark matter amplifies the chances for unification. In class (II), about a quarter of the models admits gauge coupling unification. In class (III......We investigate the possibility of gauge coupling unification in various radiative neutrino mass models, which generate neutrino masses at one- and/or two-loop level. Renormalization group running of gauge couplings is performed analytically and numerically at one- and two-loop order, respectively....... We study three representative classes of radiative neutrino mass models: (I) minimal ultraviolet completions of the dimension-7 ΔL = 2 operators which generate neutrino masses at one- and/or two-loop level without and with dark matter candidates, (II) models with dark matter which lead to neutrino...

Additional symmetries of supersymmetric KP hierarchies

International Nuclear Information System (INIS)

Stanciu, S.

1993-09-01

We investigate the additional symmetries of several supersymmetric KP hierarchies: The SKP hierarchy of Manin and Radul, the SKP 2 hierarchy, and the Jacobian SKP hierarchy. The main technical tool is the supersymmetric generalisation of a map originally due to Radul between the Lie algebra of superdifferential operators and the Lie algebra of vector fields on the space of supersymmetric Lax operators. In the case of the Manin-Radul SKP hierarchy we identify additional symmetries which form an algebra isomorphic to a subalgebra of superdifferential operators; whereas in the case of the Jacobian SKP, the (additional) symmetries are identified with the algebra itself. (orig.)

Supersymmetric probes on the conifold

International Nuclear Information System (INIS)

Arean, Daniel; Crooks, David E.; Ramallo, Alfonso V.

2004-01-01

We study the supersymmetric embeddings of different D-brane probes in the AdS 5 xT 1,1 geometry. The main tool employed is kappa symmetry and the cases studied include D3-, D5- and D7-branes. We find a family of three-cycles of the T 1,1 space over which a D3-brane can be wrapped supersymmetrically and we determine the field content of the corresponding gauge theory duals. Supersymmetric configurations of D5-branes wrapping a two-cycle and of spacetime filling D7-branes are also found. The configurations in which the entire T 1,1 space is wrapped by a D5-brane (baryon vertex) and a D7-brane are also studied. Some other embeddings which break supersymmetry but are nevertheless stable are also determined. (author)

With neutrino masses revealed, proton decay is the missing link

International Nuclear Information System (INIS)

Pati, J.C.

1999-01-01

By way of paying tribute to Abdus Salam, I recall the ideas of higher unification that he and I initiated. I discuss the current status of those ideas in the light of recent developments, including those of: (a) gauge coupling unification, (b) discovery of neutrino-oscillation at SuperKamiokande, and (c) ongoing searches for proton decay. It is noted that the mass of ν τ (∼ 1/20 eV), suggested by the SuperK result, provides clear support for the route to higher unification based on the ideas of (i) SU(4)-color, (ii) left-right symmetry and (iii) supersymmetry. The change in perspective, pertaining to both gauge coupling unification and proton decay, brought forth by supersymmetry and superstrings, is noted. And, the beneficial roles of string-symmetries in addressing certain naturalness problems of supersymmetry, including that of rapid proton decay, are emphasized. Further, it is noted that with neutrino masses and coupling unification revealed, proton decay is the missing link. Following recent joint work with K. Babu and F. Wilczek, based on supersymmetric unification, it is remarked that the SuperKamiokande result on neutrino oscillation in fact enhances the expected rate of proton decay compared to prior estimates. Thus, assuming supersymmetric unification, one expects that the discovery of proton decay should not be far behind. (author)

A supersymmetric Skyrme model

International Nuclear Information System (INIS)

Gudnason, Sven Bjarke; Nitta, Muneto; Sasaki, Shin

2016-01-01

Construction of a supersymmetric extension of the Skyrme term was a long-standing problem because of the auxiliary field problem; that is, the auxiliary field may propagate and cannot be eliminated, and the problem of having fourth-order time derivative terms. In this paper, we construct for the first time a supersymmetric extension of the Skyrme term in four spacetime dimensions, in the manifestly supersymmetric superfield formalism that does not suffer from the auxiliary field problem. Chiral symmetry breaking in supersymmetric theories results not only in Nambu-Goldstone (NG) bosons (pions) but also in the same number of quasi-NG bosons so that the low-energy theory is described by an SL(N,ℂ)-valued matrix field instead of SU(N) for NG bosons. The solution of auxiliary fields is trivial on the canonical branch of the auxiliary field equation, in which case our model results in a fourth-order derivative term that is not the Skyrme term. For the case of SL(2,ℂ), we find explicitly a nontrivial solution to the algebraic auxiliary field equations that we call a non-canonical branch, which when substituted back into the Lagrangian gives a Skyrme-like model. If we restrict to a submanifold, where quasi-NG bosons are turned off, which is tantamount to restricting the Skyrme field to SU(2), then the fourth-order derivative term reduces exactly to the standard Skyrme term. Our model is the first example of a nontrivial auxiliary field solution in a multi-component model.

The particle interpretation of N = 1 supersymmetric spin foams

Energy Technology Data Exchange (ETDEWEB)

Baccetti, Valentina [Dipartimento di Fisica ' E. Amaldi' , Universita degli Studi Roma Tre, Via della Vasca Navale 84, 00146 Roma (Italy); Livine, Etera R [Laboratoire de Physique, ENS Lyon, CNRS UMR 5672, 46 Allee d' Italie, 69007 Lyon (France); Ryan, James P, E-mail: baccetti@neve.fis.uniroma3.i, E-mail: etera.livine@ens-lyon.f, E-mail: james.ryan@aei.mpg.d [MPI fuer Gravitationsphysik, Albert Einstein Institute, Am Muehlenberg 1, D-14476 Potsdam (Germany)

2010-11-21

We show that N = 1-supersymmetric BF theory in 3D leads to a supersymmetric spin foam amplitude via a lattice discretization. Furthermore, by analysing the supersymmetric quantum amplitudes, we show that they can be re-interpreted as 3D gravity coupled to embedded fermionic Feynman diagrams.

The particle interpretation of N = 1 supersymmetric spin foams

International Nuclear Information System (INIS)

Baccetti, Valentina; Livine, Etera R; Ryan, James P

2010-01-01

We show that N = 1-supersymmetric BF theory in 3D leads to a supersymmetric spin foam amplitude via a lattice discretization. Furthermore, by analysing the supersymmetric quantum amplitudes, we show that they can be re-interpreted as 3D gravity coupled to embedded fermionic Feynman diagrams.

From chaos to unification: U theory vs. M theory

International Nuclear Information System (INIS)

Ye, Fred Y.

2009-01-01

A unified physical theory called U theory, that is different from M theory, is defined and characterized. U theory, which includes spinor and twistor theory, loop quantum gravity, causal dynamical triangulations, E-infinity unification theory, and Clifford-Finslerian unifications, is based on physical tradition and experimental foundations. In contrast, M theory pays more attention to mathematical forms. While M theory is characterized by supersymmetry string theory, U theory is characterized by non-supersymmetry unified field theory.

On the supersymmetric solitons and monopoles

International Nuclear Information System (INIS)

Hruby, J.

1978-01-01

The basic results in a new trend in supersymmetry and soliton theory are presented. It is shown that the soliton expectation value of the energy operator is mass of the soliton without the quantum corrections. A new supersymmetric monopole model in three dimensions is constructed by generalization of the supersymmetric sine-Gordon model in one space dimension

Supersymmetric sigma models

International Nuclear Information System (INIS)

Bagger, J.A.

1984-09-01

We begin to construct the most general supersymmetric Lagrangians in one, two and four dimensions. We find that the matter couplings have a natural interpretation in the language of the nonlinear sigma model

Supersymmetric sigma models

Energy Technology Data Exchange (ETDEWEB)

Bagger, J.A.

1984-09-01

We begin to construct the most general supersymmetric Lagrangians in one, two and four dimensions. We find that the matter couplings have a natural interpretation in the language of the nonlinear sigma model.

The Unification of Private International Law

Directory of Open Access Journals (Sweden)

Emira Kazazi

2015-07-01

Full Text Available Civil and the common law approaching Europe is no longer a “future project”, but more and more rather a present attempt (Kötz, 2003 – 2004. In this prism, concentrating on the European International Private Law within the space of mixed jurisdictions, it may seem surprising in light of the attempts to create a new European ius commune. But is it possible that a unification of the material law may sign the start of the end of the European conflicts of laws? Last but not the least private international law is not just a choice of law. The unification of the private law, in its definition as a concept, does not influence two of the three pillars of the private international law: respectively, that of the jurisdiction and recognition as well as implementation of foreign decisions.

On the vacuum of the minimal nonsupersymmetric SO(10) unification

CERN Document Server

Bertolini, Stefano; Malinsky, Michal

2010-01-01

We study a class of nonsupersymmetric SO(10) grand unified scenarios where the first stage of the symmetry breaking is driven by the vacuum expectation values of the 45-dimensional adjoint representation. Three decade old results claim that such a Higgs setting may lead exclusively to the flipped SU(5) x U(1) intermediate stage. We show that this conclusion is actually an artifact of the tree level potential. The study of the accidental global symmetries emerging in various limits of the scalar potential offers a simple understanding of the tree level result and a rationale for the drastic impact of quantum corrections. We scrutinize in detail the simplest and paradigmatic case of the 45_{H} + 16_{H} Higgs sector triggering the breaking of SO(10) to the standard electroweak model. We show that the minimization of the one-loop effective potential allows for intermediate SU(4)_C x SU(2)_L x U(1)_R and SU(3)_c x SU(2)_L x SU(2)_R x U(1)_{B-L} symmetric stages as well. These are the options favoured by gauge unif...

Classification of supersymmetric backgrounds of string theory

NARCIS (Netherlands)

Gran, Ulf; Gutowski, Jan; Papadopoulos, George; Roest, Diederik

2007-01-01

We review the recent progress made towards the classification of supersymmetric solutions in ten and eleven dimensions with emphasis on those of IIB supergravity. In particular, the spinorial geometry method is outlined and adapted to nearly maximally supersymmetric backgrounds.We then demonstrate

Non-local deformation of a supersymmetric field theory

Energy Technology Data Exchange (ETDEWEB)

Zhao, Qin [National University of Singapore, Department of Physics, Singapore (Singapore); Faizal, Mir [University of Lethbridge, Department of Physics and Astronomy, Lethbridge (Canada); University of British Columbia - Okanagan, Irving K. Barber School of Arts and Sciences, Kelowna, BC (Canada); Shah, Mushtaq B.; Ganai, Prince A. [National Institute of Technology, Department of Physics, Srinagar, Kashmir (India); Bhat, Anha [National Institute of Technology, Department of Metallurgical and Materials Engineering, Srinagar (India); Zaz, Zaid [University of Kashmir, Department of Electronics and Communication Engineering, Srinagar, Kashmir (India); Masood, Syed; Raza, Jamil; Irfan, Raja Muhammad [International Islamic University, Department of Physics, Islamabad (Pakistan)

2017-09-15

In this paper, we will analyze a supersymmetric field theory deformed by generalized uncertainty principle and Lifshitz scaling. It will be observed that this deformed supersymmetric field theory contains non-local fractional derivative terms. In order to construct such a deformed N = 1 supersymmetric theory, a harmonic extension of functions will be used. However, the supersymmetry will only be preserved for a free theory and will be broken by the inclusion of interaction terms. (orig.)

Spectral properties in supersymmetric matrix models

International Nuclear Information System (INIS)

Boulton, Lyonell; Garcia del Moral, Maria Pilar; Restuccia, Alvaro

2012-01-01

We formulate a general sufficiency criterion for discreteness of the spectrum of both supersymmmetric and non-supersymmetric theories with a fermionic contribution. This criterion allows an analysis of Hamiltonians in complete form rather than just their semiclassical limits. In such a framework we examine spectral properties of various (1+0) matrix models. We consider the BMN model of M-theory compactified on a maximally supersymmetric pp-wave background, different regularizations of the supermembrane with central charges and a non-supersymmetric model comprising a bound state of N D2 with m D0. While the first two examples have a purely discrete spectrum, the latter has a continuous spectrum with a lower end given in terms of the monopole charge.

Vector supersymmetric multiplets in two dimensions

International Nuclear Information System (INIS)

Khattab, Mohammad

1990-01-01

Author.The invariance of both, N=1 supersymmetric yang-Mills theory and N-1 supersymmetric off-shell Wess-Zumino model in four dimensions is proved. Dimensional reduction is then applied to obtain super Yang-Mills theory with extended supersymmetry, N=2, in two dimensions. The resulting theory is then truncated to N=1 super Yang-Mills and with further truncation, N=1/2 supersymmetry is shown to be possible. Then, using the duality transformations, we find the off-shell supersymmetry algebra is closed and that the auxiliary fields are replaced by four-rank antisymmetric tensors with Gauge symmetry. Finally, the mechanism of dimensional reduction is then applied to obtain N=2 extended off-shell supersymmetric model with two gauge vector fields

Supersymmetric regulators and supercurrent anomalies

International Nuclear Information System (INIS)

Majumdar, P.; Poggio, E.C.; Schnitzer, H.J.

1980-01-01

The supercurrent anomalies of the supercurrent deltasub(μ) of the supersymmetric Yang-Mills theory in Wess-Zumino gauge are computed using the supersymmetric dimensional regulator of Siegel. It is shown that γsub(μ)deltasup(μ) = 0 and deltasub(μ)deltasup(μ) unequal 0 in agreement with an earlier calculation based on the Adler-Rosenberg method. The problem of exhibiting the chiral anomaly and a regulator for local supersymmetry suggests that the interpretation of dimensional reduction in component language is incomplete. (orig.)

The gauge technique in supersymmetric QED2

NARCIS (Netherlands)

Roo, M. de; Steringa, J.J.

1988-01-01

We construct an extension of the gauge technique to two-dimensional supersymmetric gauge theories. This involves a derivation of the spectral representation of a scalar superpropagator in two dimensions. We apply the method to the massive supersymmetric Schwinger model. In the case that the gauge

Dynamics of supersymmetric chameleons

International Nuclear Information System (INIS)

Brax, Philippe; Davis, Anne-Christine; Sakstein, Jeremy

2013-01-01

We investigate the cosmological dynamics of a class of supersymmetric chameleon models coupled to cold dark matter fermions. The model includes a cosmological constant in the form of a Fayet-Illiopoulos term, which emerges at late times due to the coupling of the chameleon to two charged scalars. Supergravity corrections ensure that the supersymmetric chameleons are efficiently screened in all astrophysical objects of interest, however this does not preclude the enhancement of gravity on linear cosmological scales. We solve the modified equations for the growth of cold dark matter density perturbations in closed form in the matter era. Using this, we go on to derive the modified linear power spectrum which is characterised by two scales, the horizon size at matter-radiation equality and at the redshift when the chameleon reaches the minimum of its effective potential. We analyse the deviations from the ΛCDM predictions in the linear regime. We find that there is generically a region in the model's parameter space where the model's background cosmology coincides with that of the ΛCDM model. Furthermore, we find that characteristic deviations from ΛCDM are present on the matter power spectrum providing a clear signature of supersymmetric chameleons

Supersymmetric contribution to the electroweak ρ parameter

International Nuclear Information System (INIS)

Drees, M.; Hagiwara, K.

1990-01-01

Contributions to the electroweak ρ parameter, the ratio of the neutral- and charged-current strengths at zero-momentum transfer, are studied in the minimal extension of the standard model (SM) with softly broken supersymmetry. The effects of the extended Higgs sector, the gaugino-Higgsino sector, the light-squark--slepton sector and that of the stop-sbottom sector are studied separately, and the role of the custodial SU(2) V symmetry in each sector is clarified. The stop-sbottom sector is found to give potentially a most significant contribution to δρ which can double the standard-model contribution from the top-bottom sector, whereas all the remaining sectors contribute to δρ at the level of at most a few x10 -3 . In the supergravity model with radiative electroweak gauge symmetry breaking there are no extra sources of the SU(2) V breaking at the grand unification scale other than those present already in the SM, and the resulting δρ is found to be significantly smaller than in the general case. Constraints on the allowed range of δρ in the supergravity models are given by taking account of existing and prospective experimental mass limits of additional particles at CERN LEP and Sp bar pS and Fermilab Tevatron

Strong/weak coupling duality relations for non-supersymmetric string theories

International Nuclear Information System (INIS)

Blum, J.D.; Dienes, K.R.

1998-01-01

Both the supersymmetric SO(32) and E 8 x E 8 heterotic strings in ten dimensions have known strong-coupling duals. However, it has not been known whether there also exist strong-coupling duals for the non-supersymmetric heterotic strings in ten dimensions. In this paper, we construct explicit open-string duals for the circle compactifications of several of these non-supersymmetric theories, among them the tachyon-free SO(16) x SO(16) string. Our method involves the construction of heterotic and open-string interpolating models that continuously connect non-supersymmetric strings to supersymmetric strings. We find that our non-supersymmetric dual theories have exactly the same massless spectra as their heterotic counterparts within a certain range of our interpolations. We also develop a novel method for analyzing the solitons of non-supersymmetric open-string theories, and find that the solitons of our dual theories also agree with their heterotic counterparts. These are therefore the first known examples of strong/weak coupling duality relations between non-supersymmetric, tachyon-free string theories. Finally, the existence of these strong-coupling duals allows us to examine the non-perturbative stability of these strings, and we propose a phase diagram for the behavior of these strings as a function of coupling and radius. (orig.)

Instantons in supersymmetric theories

International Nuclear Information System (INIS)

Novikov, V.A.; Shifman, M.A.; Vajnshtejn, A.I.; Zakharov, V.I.

1982-01-01

Instanton effects are considered for a sample of supersymmetric theories: quantum mechanics, gluodynamics. Higgs model. The problem is how to reconcile the apparent lack of the boson-fermion symmetry in the effective instanton induced interaction with supersymmetry of the corresponding lagrangians. It is shown that in case of quantum mechanics and Higgs model there is no conflict between supersymmetry and the instanton calculus since the Ward identities, associated with the supersymmetry transformations, are satisfied. In case of supersymmetric gluodynamics the standard instanton calculus explicity violates the Ward identities. This is due to the lack of symmetry in the standard class of classical solutions used in the instanton calculus

[Theory of elementary particles studies in weak interaction and grand unification and studies in accelerator design

International Nuclear Information System (INIS)

1991-01-01

This report discusses research in high energy physics on the following topics: rare b decays; flavor changing top decays;neutrino physics; standard model; cp violation; heavy ion collisions; electron-positron interactions; electron-hadron interactions; hadron-hadron interactions; deep inelastic scattering; and grand unified models

On the maximal superalgebras of supersymmetric backgrounds

International Nuclear Information System (INIS)

Figueroa-O'Farrill, Jose; Hackett-Jones, Emily; Moutsopoulos, George; Simon, Joan

2009-01-01

In this paper we give a precise definition of the notion of a maximal superalgebra of certain types of supersymmetric supergravity backgrounds, including the Freund-Rubin backgrounds, and propose a geometric construction extending the well-known construction of its Killing superalgebra. We determine the structure of maximal Lie superalgebras and show that there is a finite number of isomorphism classes, all related via contractions from an orthosymplectic Lie superalgebra. We use the structure theory to show that maximally supersymmetric waves do not possess such a maximal superalgebra, but that the maximally supersymmetric Freund-Rubin backgrounds do. We perform the explicit geometric construction of the maximal superalgebra of AdS 4 X S 7 and find that it is isomorphic to osp(1|32). We propose an algebraic construction of the maximal superalgebra of any background asymptotic to AdS 4 X S 7 and we test this proposal by computing the maximal superalgebra of the M2-brane in its two maximally supersymmetric limits, finding agreement.

Leptogenesis in the left-right supersymmetric model

International Nuclear Information System (INIS)

Frank, M.

2004-01-01

We analyze the effects of the current neutrino data on thermal leptogenesis and 0νββ decay in a fully left-right extension of the minimal supersymmetric model. The model has several additional phases compared to the minimal supersymmetric model. These phases appear from both the heavy and light neutrino sectors: two CKM-type phases and four Majorana phases which give new contributions to CP-violating parameters and leptogenesis. We study observable effects of these phases on leptogenesis in most general neutrino mixing scenarios, with either hierarchical, inverse hierarchical, or quasidegenerate light and heavy neutrinos. We comment on the effects of these scenarios on the 0νββ decay. The CP-violating phases in both the heavy and light neutrino sectors of the left-right supersymmetric model have unique features, resulting in bounds on heavy neutrino masses different from the minimal scenario in leptogenesis, and which may distinguish the model from other supersymmetric scenarios

Gauge coupling unification in six dimensions

Energy Technology Data Exchange (ETDEWEB)

Lee, H.M. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)]|[Carnegie-Mellon Univ., Pittsburgh, PA (United States). Dept. of Physics

2006-11-15

We compute the one-loop gauge couplings in six-dimensional non-Abelian gauge theories on the T{sup 2}/Z{sub 2} orbifold with general GUT breaking boundary conditions. For concreteness, we apply the obtained general formulae to the gauge coupling running in a 6D SO(10) orbifold GUT where the GUT group is broken down to the standard model gauge group up to an extra U(1). We find that the one-loop corrections depend on the parity matrices encoding the orbifold boundary conditions as well as the volume and shape moduli of extra dimensions. When the U(1) is broken by the VEV of bulk singlets, the accompanying extra color triplets also affect the unification of the gauge couplings. In this case, the B-L breaking scale is closely linked to the compactification scales for maintaining a success of the gauge coupling unification. (orig.)

M theory: a possible unification of physics laws

International Nuclear Information System (INIS)

Fernandes, Alexandre da Silva; Silva, Diego Oliveira Nolasco da; Sousa, Claudio Manoel Gomes de

2011-01-01

Full text: Physics has two pillars which are mutually incompatible: quantum field theory and general relativity theory. Throughout its history, various unifications have been made, and in attempts to have a better understanding of the birth and formation of the Universe is also necessary to unify these pillars. This unification may require 11 dimensions, and 6 of them are compressed so that it cannot be seen with existing instruments. These dimensions are the spaces in which the strings vibrate, and each mode of vibration corresponds to a particle. The last dimension shows that the universe is a brane, it is in full motion in the multiverse and the collision of two branes can answer the biggest problem of cosmology: what was the Big Bang? Black holes can be explained using a theory that contains gravity and quantum mechanics. The theory is still being developed, some problems are being solved and the main one is the experimental problem, because it requires energy levels that are not yet achieved by current particle accelerators. This work presents M theory as a possibility of unification between the micro and macro, which maybe leading us to the theory of everything. (author)

M theory: a possible unification of physics laws

Energy Technology Data Exchange (ETDEWEB)

Fernandes, Alexandre da Silva; Silva, Diego Oliveira Nolasco da; Sousa, Claudio Manoel Gomes de [Universidade Catolica de Brasilia (UCB), DF (Brazil)

2011-07-01

Full text: Physics has two pillars which are mutually incompatible: quantum field theory and general relativity theory. Throughout its history, various unifications have been made, and in attempts to have a better understanding of the birth and formation of the Universe is also necessary to unify these pillars. This unification may require 11 dimensions, and 6 of them are compressed so that it cannot be seen with existing instruments. These dimensions are the spaces in which the strings vibrate, and each mode of vibration corresponds to a particle. The last dimension shows that the universe is a brane, it is in full motion in the multiverse and the collision of two branes can answer the biggest problem of cosmology: what was the Big Bang? Black holes can be explained using a theory that contains gravity and quantum mechanics. The theory is still being developed, some problems are being solved and the main one is the experimental problem, because it requires energy levels that are not yet achieved by current particle accelerators. This work presents M theory as a possibility of unification between the micro and macro, which maybe leading us to the theory of everything. (author)

Higher dimensional supersymmetric quantum mechanics and Dirac ...

Indian Academy of Sciences (India)

We exhibit the supersymmetric quantum mechanical structure of the full 3+1 dimensional Dirac equation considering `mass' as a function of coordinates. Its usefulness in solving potential problems is discussed with specific examples. We also discuss the `physical' significance of the supersymmetric states in this formalism.

Instantons and Borel resummability for the perturbed supersymmetric anharmonic oscillator

International Nuclear Information System (INIS)

Verbaarschot, J.J.M.; West, P.

1991-01-01

In this paper we give an analytical derivation of the large-order behavior of the perturbation series for both the ground state and the excited states of the supersymmetric anharmonic oscillator and of the anharmonic oscillator obtained from the supersymmetric case by varying the strength of the fermion coupling. The results which are obtained with the help of instanton calculus coincide with those obtained numerically in previous work. The large-order perturbation series of the ground state vanishes in the supersymmetric case, whereas away from the supersymmetric point the perturbation series diverges factorially. The perturbation series of the excited states diverges factorially both at the supersymmetric point and away from this point

Supersymmetric quantum corrections and Poisson-Lie T-duality

International Nuclear Information System (INIS)

Assaoui, F.; Lhallabi, T.; Abdus Salam International Centre for Theoretical Physics, Trieste

2000-07-01

The quantum actions of the (4,4) supersymmetric non-linear sigma model and its dual in the Abelian case are constructed by using the background superfield method. The propagators of the quantum superfield and its dual and the gauge fixing actions of the original and dual (4,4) supersymmetric sigma models are determined. On the other hand, the BRST transformations are used to obtain the quantum dual action of the (4,4) supersymmetric nonlinear sigma model in the sense of Poisson-Lie T-duality. (author)

Nearly Supersymmetric Dark Atoms

Energy Technology Data Exchange (ETDEWEB)

Behbahani, Siavosh R.; Jankowiak, Martin; /SLAC /Stanford U., ITP; Rube, Tomas; /Stanford U., ITP; Wacker, Jay G.; /SLAC /Stanford U., ITP

2011-08-12

Theories of dark matter that support bound states are an intriguing possibility for the identity of the missing mass of the Universe. This article proposes a class of models of supersymmetric composite dark matter where the interactions with the Standard Model communicate supersymmetry breaking to the dark sector. In these models supersymmetry breaking can be treated as a perturbation on the spectrum of bound states. Using a general formalism, the spectrum with leading supersymmetry effects is computed without specifying the details of the binding dynamics. The interactions of the composite states with the Standard Model are computed and several benchmark models are described. General features of non-relativistic supersymmetric bound states are emphasized.

Supersymmetric inflationary cosmology

International Nuclear Information System (INIS)

Ruiz-Altaba, M.

1986-06-01

An action is presented, within the framework of supergravity unification, which satisfies all experimental and cosmological constraints. In intermediate scale, around 10 10 - 10 11 GeV, arises from a critical examination of inflation, supersymmetry breaking, fermion masses, proton decay, baryogenesis, and electroweak breaking - including neutrino oscillations and CP violation. Careful consideration is given to some relevant calculations. 86 refs., 10 figs., 5 tabs

Model-based object classification using unification grammars and abstract representations

Science.gov (United States)

Liburdy, Kathleen A.; Schalkoff, Robert J.

1993-04-01

The design and implementation of a high level computer vision system which performs object classification is described. General object labelling and functional analysis require models of classes which display a wide range of geometric variations. A large representational gap exists between abstract criteria such as `graspable' and current geometric image descriptions. The vision system developed and described in this work addresses this problem and implements solutions based on a fusion of semantics, unification, and formal language theory. Object models are represented using unification grammars, which provide a framework for the integration of structure and semantics. A methodology for the derivation of symbolic image descriptions capable of interacting with the grammar-based models is described and implemented. A unification-based parser developed for this system achieves object classification by determining if the symbolic image description can be unified with the abstract criteria of an object model. Future research directions are indicated.

Dynamics of supersymmetric chameleons

Energy Technology Data Exchange (ETDEWEB)

Brax, Philippe [Institut de Physique Theorique, CEA, IPhT, CNRS, URA 2306, F-91191Gif/Yvette Cedex (France); Davis, Anne-Christine; Sakstein, Jeremy, E-mail: Philippe.Brax@cea.fr, E-mail: A.C.Davis@damtp.cam.ac.uk, E-mail: J.A.Sakstein@damtp.cam.ac.uk [DAMTP, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA (United Kingdom)

2013-10-01

We investigate the cosmological dynamics of a class of supersymmetric chameleon models coupled to cold dark matter fermions. The model includes a cosmological constant in the form of a Fayet-Illiopoulos term, which emerges at late times due to the coupling of the chameleon to two charged scalars. Supergravity corrections ensure that the supersymmetric chameleons are efficiently screened in all astrophysical objects of interest, however this does not preclude the enhancement of gravity on linear cosmological scales. We solve the modified equations for the growth of cold dark matter density perturbations in closed form in the matter era. Using this, we go on to derive the modified linear power spectrum which is characterised by two scales, the horizon size at matter-radiation equality and at the redshift when the chameleon reaches the minimum of its effective potential. We analyse the deviations from the ΛCDM predictions in the linear regime. We find that there is generically a region in the model's parameter space where the model's background cosmology coincides with that of the ΛCDM model. Furthermore, we find that characteristic deviations from ΛCDM are present on the matter power spectrum providing a clear signature of supersymmetric chameleons.

Gauge unification of fundamental forces

International Nuclear Information System (INIS)

Salam, A.

1980-02-01

After having reviewed briefly the last twenty years' progress in the theory of unification, with the twin aspects of development of a gauge theory of basic interactions linked with internal symmetry and the spontaneous breaking of these symmetries, the Nobel prize winners have summarized the present situation and the immediate problems. At the end, an extrapolation of the future is also given

Supersymmetric Yang-Mills theory on conformal supergravity backgrounds in ten dimensions

Energy Technology Data Exchange (ETDEWEB)

Medeiros, Paul de; Figueroa-O’Farrill, José [Maxwell Institute and School of Mathematics, The University of Edinburgh,James Clerk Maxwell Building, Peter Guthrie Tait Road, Edinburgh EH9 3FD (United Kingdom)

2016-03-14

We consider bosonic supersymmetric backgrounds of ten-dimensional conformal supergravity. Up to local conformal isometry, we classify the maximally supersymmetric backgrounds, determine their conformal symmetry superalgebras and show how they arise as near-horizon geometries of certain half-BPS backgrounds or as a plane-wave limit thereof. We then show how to define Yang-Mills theory with rigid supersymmetry on any supersymmetric conformal supergravity background and, in particular, on the maximally supersymmetric backgrounds. We conclude by commenting on a striking resemblance between the supersymmetric backgrounds of ten-dimensional conformal supergravity and those of eleven-dimensional Poincaré supergravity.

Production and decay of supersymmetric particles at future colliders

International Nuclear Information System (INIS)

Bartl, A.; Majerotto, W.; Moesslacher, B.

1991-01-01

We describe how supersymmetric particles could be detected at the new colliders HERA, LEP 200, LHC, SSC, and at the possible future linear e + e - collider. We shall present theoretical predictions for production cross sections and decay probabilities, as well as for the important signatures. Our calculations will be based on the Minimal Supersymmetric Standard Model (MSSM) which is the simplest supersymmetric extension of the Standard Model. (authors)

Similarity-Based Unification: A Multi-Adjoint Approach

Czech Academy of Sciences Publication Activity Database

Medina, J.; Ojeda-Aciego, M.; Vojtáš, Peter

2004-01-01

Roč. 146, č. 1 (2004), s. 43-62 ISSN 0165-0114 Source of funding: V - iné verejné zdroje Keywords : similarity * fuzzy unification Subject RIV: BA - General Mathematics Impact factor: 0.734, year: 2004

Gauge unification of basic forces particularly of gravitation with strong interactions

International Nuclear Information System (INIS)

Salam, A.

1977-01-01

Corresponding to the two known types of gauge theories, Yang-Mills with spin-one mediating particles and Einstein Weyl with spin-two mediating particles, it is speculated that two distinct gauge unifications of the basic forces appear to be taking place. One is the familiar Yang-Mills unification of weak and electromagnetic forces with the strong. The second is the less familiar gauge unification of gravitation with spin-two tensor-dominated aspects of strong interactions. It is proposed that there are strongly interacting spin-two strong gravitons obeying Einstein's equations, and their existence gives a clue to an understanding of the (partial) confinement of quarks, as well as of the concept of hadronic temperature, through the use of Schwarzschild de-Sitter-like partially confining solitonic solutions of the strong gravity Einstein equation

A new gauge for supersymmetric abelian gauge theories

International Nuclear Information System (INIS)

Smith, A.W.; Barcelos Neto, J.

1984-01-01

A new gauge for supersymmetric abelian gauge theories is presented. It is shown that this new gauge allows us to obtain terms which usually come as radiative corrections to the supersymmetric abelian gauge theories when one uses the Wess-Zumino gauge. (Author) [pt

On quantization of supersymmetric theories

International Nuclear Information System (INIS)

Smilga, A.V.

1985-01-01

A recipe to resolve ordering ambiguities in the quantum hamiltonian of supersymmetric theories is suggested. The Weyl ordering prescription for supercharge operators should be employed to preserve SUSY algebra on the quantum level. The quantum hamiltonian does not generally coincide with the Weyl ordered classical hamiltonian, the difference being due to the fact that the Weyl symbol of anticommutator of supercharges does not generally coincide with the Poisson bracket of their Weyl symbols (i.e. the classical hamiltonian). The suggested procedure is applied in the examples of N=1 and N=2 supersymmetric σ-models analyzed in the constant field limit

N=2 supersymmetric dynamics for pedestrians

CERN Document Server

Tachikawa, Yuji

2015-01-01

Understanding the dynamics of gauge theories is crucial, given the fact that all known interactions are based on the principle of local gauge symmetry. Beyond the perturbative regime, however, this is a notoriously difficult problem. Requiring invariance under supersymmetry turns out to be a suitable tool for analyzing supersymmetric gauge theories over a larger region of the space of parameters. Supersymmetric quantum field theories in four dimensions with extended N=2 supersymmetry are further constrained and have therefore been a fertile field of research in theoretical physics for quite some time. Moreover, there are far-reaching mathematical ramifications that have led to a successful dialogue with differential and algebraic geometry. These lecture notes aim to introduce students of modern theoretical physics to the fascinating developments in the understanding of N=2 supersymmetric gauge theories in a coherent fashion. Starting with a gentle introduction to electric-magnetic duality, the author guides r...

Macroscopic constraints on string unification

International Nuclear Information System (INIS)

Taylor, T.R.

1989-03-01

The comparison of sting theory with experiment requires a huge extrapolation from the microscopic distances, of order of the Planck length, up to the macroscopic laboratory distances. The quantum effects give rise to large corrections to the macroscopic predictions of sting unification. I discus the model-independent constraints on the gravitational sector of string theory due to the inevitable existence of universal Fradkin-Tseytlin dilatons. 9 refs

Search for supersymmetry in pp collisions at sqrt(s) = 7TeV in final states with missing transverse momentum, b-jets and no leptons with the ATLAS detector

CERN Document Server

The ATLAS collaboration

2011-01-01

A search for supersymmetric particles in events with large missing transverse momentum, heavy flavour jet candidates and no leptons (e, mu) in sqrt(s) = 7TeV proton-proton collisions is presented. In a data sample corresponding to an integrated luminosity of 833\\pb recorded by the ATLAS experiment at the Large Hadron Collider, no significant excess is observed with respect to the prediction for Standard Model processes. For R-parity conserving models in which sbottoms are the only squarks to appear in the gluino decay cascade, gluino masses below 720~GeV are excluded at the 95\\% C.L. Model-independent cross section upper limits are provided in the context of simplified models and the result is also interpreted in the context of grand unification SO(10) models.

Solvable potentials derived from supersymmetric quantum mechanics

International Nuclear Information System (INIS)

Levai, G.

1994-01-01

The introduction of supersymmetric quantum mechanics has generated renewed interest in solvable problems of non-relativistic quantum mechanics. This approach offers an elegant way to describe different, but isospectral potentials by interpreting the degeneracy of their energy levels in terms of supersymmetry. The original ideas of supersymmetric quantum mechanics have been developed further in many respects in the past ten years, and have been applied to a large variety of physical problems. The purpose of this contribution is to give a survey of supersymmetric quantum mechanics and its applications to solvable quantum mechanical potentials. Its relation to other models describing isospectral potentials is also discussed here briefly, as well as some of its practical applications in various branches of physics. (orig.)

Gauge hierarchy problem in grand unified theories

International Nuclear Information System (INIS)

Alhendi, H.A.A.

1982-01-01

In grand unification schemes, several mass scales are to be introduced, with some of them much larger than all the others, to cope with experimental observations, in which elementary particles of higher masses require higher energy to observe them than elementary particles of lower masses. There have been controversial arguments in the literature on such hierarchical scale structure, when radiative corrections are taken into account. It has been asserted that the gauge hierarchy depends on the choice of the subtraction point (in the classical field space), of the four-point function at zero external momentum. It also has been asserted that the gauge hierarchy problem whenever it is possible to be maintained in one sector of particles, it also is possible to be maintained in the other sectors. These two problems have been studied in a prototype model, namely an 0(3)-model with two triplets of real scalar Higgs fields. Our analysis shows that, within ordinary perturbation theory, none of these two problems is quite correct

A supersymmetric SYK-like tensor model

Energy Technology Data Exchange (ETDEWEB)

Peng, Cheng; Spradlin, Marcus; Volovich, Anastasia [Department of Physics, Brown University,Providence, RI, 02912 (United States)

2017-05-11

We consider a supersymmetric SYK-like model without quenched disorder that is built by coupling two kinds of fermionic N=1 tensor-valued superfields, “quarks” and “mesons”. We prove that the model has a well-defined large-N limit in which the (s)quark 2-point functions are dominated by mesonic “melon” diagrams. We sum these diagrams to obtain the Schwinger-Dyson equations and show that in the IR, the solution agrees with that of the supersymmetric SYK model.

A supersymmetric SYK-like tensor model

International Nuclear Information System (INIS)

Peng, Cheng; Spradlin, Marcus; Volovich, Anastasia

2017-01-01

We consider a supersymmetric SYK-like model without quenched disorder that is built by coupling two kinds of fermionic N=1 tensor-valued superfields, “quarks” and “mesons”. We prove that the model has a well-defined large-N limit in which the (s)quark 2-point functions are dominated by mesonic “melon” diagrams. We sum these diagrams to obtain the Schwinger-Dyson equations and show that in the IR, the solution agrees with that of the supersymmetric SYK model.

Supersymmetric quantum mechanics

International Nuclear Information System (INIS)

Crombrugghe, M. de; Rittenberg, V.

1982-12-01

We give a general construction for supersymmetric Hamiltonians in quantum mechanics. We find that N-extended supersymmetry imposes very strong constraints, and for N > 4 the Hamiltonian is integrable. We give a variety of examples, for one-particle and for many-particle systems, in different numbers of dimensions. (orig.)

N=1 supersymmetric extension of the baby Skyrme model

International Nuclear Information System (INIS)

Adam, C.; Queiruga, J. M.; Sanchez-Guillen, J.; Wereszczynski, A.

2011-01-01

We construct a method to supersymmetrize higher kinetic terms and apply it to the baby Skyrme model. We find that there exist N=1 supersymmetric extensions for baby Skyrme models with arbitrary potential.

Fun with supersymmetric quantum mechanics

International Nuclear Information System (INIS)

Freedman, B.; Cooper, F.

1984-04-01

One reason for studying supersymmetric quantum mechanics is that there are a class of superpotentials W(x) which behave at large x as x/sup α/ for which we know from general arguments whether SUSY is broken or unbroken. Thus one can use these superpotentials to test various ideas about how to see if supersymmetry is broken in an arbitrary model. Recently, Witten proposed a topological invariant, the Witten index Δ which counts the number of bosons minus the number of fermions having ground state energy zero. Since if supersymmetry is broken, the ground state energy cannot be zero, one expects if Δ is not zero, SUSY is preserved and the theory is not a good candidate for a realistic model. In this study we evaluate Δ for several examples, and show some unexpected peculiarities of the Witten index for certain choice of superpotentials W(x). We also discuss two other nonperturbative methods of studying supersymmetry breakdown. One involves relating supersymmetric quantum mechanics to a stochastic classical problem and the other involves considering a discrete (but not supersymmetric) version of the theory and studying its behavior as one removes the lattice cuttoff. In this survey we review the Hamiltonian and path integral approaches to supersymmetric quantum mechanics. We then discuss the related path integrals for the Witten Index and for stochastic processes and show how they are indications for supersymmetry breakdown. We then discuss a system where the superpotential W(x) has assymetrical values at +-infinity. We finally discuss nonperturbative strategies for studying supersymmetry breakdown based on introducing a lattice and studying the behavior of the ground state energy as the lattice cutoff is removed. 17 references

New dualities of supersymmetric gauge theories

CERN Document Server

2016-01-01

This book reviews a number of spectacular advances that have been made in the study of supersymmetric quantum field theories in the last few years. Highlights include exact calculations of Wilson loop expectation values, and highly nontrivial quantitative checks of the long-standing electric-magnetic duality conjectures. The book starts with an introductory article presenting a survey of recent advances, aimed at a wide audience with a background and interest in theoretical physics. The following articles are written for advanced students and researchers in quantum field theory, string theory and mathematical physics, our goal being to familiarize these readers with the forefront of current research. The topics covered include recent advances in the classification and vacuum structure of large families of N=2 supersymmetric field theories, followed by an extensive discussion of the localisation method, one of the most powerful tools for exact studies of supersymmetric field theories. The quantities that have ...

Cosmological consequences of supersymmetric flat directions

CERN Document Server

Riva, Francesco; Sarkar, Subir; Giudice, Gian

In this work we analyze various implications of the presence of large field vacum expectation values (VEVs) along supersymmetric flat direct ions during the early universe. First, we discuss supersymmetric leptogenesis and the grav itino bound. Supersym- metric thermal leptogenesis with a hierarchical right-han ded neutrino mass spectrum normally requires the mass of the lightest right-handed neu trino to be heavier than about 10 9 GeV. This is in conflict with the upper bound on the reheating t empera- ture which is found by imposing that the gravitinos generate d during the reheating stage after inflation do not jeopardize successful nucleosy nthesis. We show that a solution to this tension is actually already incorporated i n the framework, because of the presence of flat directions in the supersymmetric scalar potential. Massive right- handed neutrinos are efficiently produced non-thermally and the observed baryon asymmetry can be explained even for a reheating temperature respecting the grav- itino bound...

Supersymmetric Janus solutions in four dimensions

Energy Technology Data Exchange (ETDEWEB)

Bobev, Nikolay [Perimeter Institute for Theoretical Physics,31 Caroline Street North, ON N2L 2Y5 (Canada); Pilch, Krzysztof [Department of Physics and Astronomy, University of Southern California,Los Angeles, CA 90089 (United States); Warner, Nicholas P. [Department of Physics and Astronomy, University of Southern California,Los Angeles, CA 90089 (United States); Institut de Physique Théorique, CEA Saclay,CNRS-URA 2306, 91191 Gif sur Yvette (France); Institut des Hautes Etudes Scientifiques,Le Bois-Marie, 35 route de Chartres, Bures-sur-Yvette, 91440 (France)

2014-06-10

We use maximal gauged supergravity in four dimensions to construct the gravity dual of a class of supersymmetric conformal interfaces in the theory on the world-volume of multiple M2-branes. We study three classes of examples in which the (1+1)-dimensional defects preserve (4,4), (0,2) or (0,1) supersymmetry. Many of the solutions have the maximally supersymmetric AdS{sub 4} vacuum dual to the N=8 ABJM theory on both sides of the interface. We also find new special classes of solutions including one that interpolates between the maximally supersymmetric vacuum and a conformal fixed point with N=1 supersymmetry and G{sub 2} global symmetry. We find another solution that interpolates between two distinct conformal fixed points with N=1 supersymmetry and G{sub 2} global symmetry. In eleven dimensions, this G{sub 2} to G{sub 2} solution corresponds to a domain wall across which a magnetic flux reverses orientation.

Supersymmetric Janus solutions in four dimensions

International Nuclear Information System (INIS)

Bobev, Nikolay; Pilch, Krzysztof; Warner, Nicholas P.

2014-01-01

We use maximal gauged supergravity in four dimensions to construct the gravity dual of a class of supersymmetric conformal interfaces in the theory on the world-volume of multiple M2-branes. We study three classes of examples in which the (1+1)-dimensional defects preserve (4,4), (0,2) or (0,1) supersymmetry. Many of the solutions have the maximally supersymmetric AdS 4 vacuum dual to the N=8 ABJM theory on both sides of the interface. We also find new special classes of solutions including one that interpolates between the maximally supersymmetric vacuum and a conformal fixed point with N=1 supersymmetry and G 2 global symmetry. We find another solution that interpolates between two distinct conformal fixed points with N=1 supersymmetry and G 2 global symmetry. In eleven dimensions, this G 2 to G 2 solution corresponds to a domain wall across which a magnetic flux reverses orientation

MEG studies prohibited muon decays to explore grand unified theories of elementary particles

International Nuclear Information System (INIS)

Mori, Toshinori

2009-01-01

The MEG experiment, designed and proposed by Japanese physicists, is being carried out at Paul Scherrer Institute (PSI) in Switzerland, in collaboration with physicists from Italy, Switzerland, Russia and U.S.A. The experiment will make an extensive search for a muon's two-body decay into an electron and a gamma ray, μ→eγ, which is prohibited in the Standard Model of elementary particles, to explore Supersymmetric Grand Unified Theories. This article gives a brief description of the MEG experiment with an emphasis on the innovative experimental techniques developed to achieve the unprecedented experimental sensitivity. (author)

Supersymmetric flipped SU(5) revitalized

Energy Technology Data Exchange (ETDEWEB)

Antoniadis, I.; Ellis, J.; Hagelin, J.S.; Nanopoulos, D.V.

1987-08-06

We describe a simple N = 1 supersymmetric GUT based on the group SU(5) x U(1) which has the following virtues: the gauge group is broken down to the SU(3)/sub C/ x SU(2)/sub L/ x U(1)/sub y/ of the standard model using just 10, 10 Higgs representations, and the doublet-triplet mass splitting problem is solved naturally by a very simple missing-partner mechanism. The successful supersymmetric GUT prediction for sin/sup 2/theta/sub w/ can be maintained, whilst there are no fermion mass relations. The gauge group and representation structure of the model may be obtainable from the superstring.

Supersymmetric sigma models and composite Yang-Mills theory

International Nuclear Information System (INIS)

Lukierski, J.

1980-04-01

We describe two types of supersymmetric sigma models: with field values in supercoset space and with superfields. The notion of Riemannian symmetric pair (H,G/H) is generalized to supergroups. Using the supercoset approach the superconformal-invariant model of composite U(n) Yang-Mills fields in introduced. In the framework of the superfield approach we present with some details two versions of the composite N=1 supersymmetric Yang-Mills theory in four dimensions with U(n) and U(m) x U(n) local invariance. We argue that especially the superfield sigma models can be used for the description of pre-QCD supersymmetric dynamics. (author)

Supersymmetric leptogenesis with a light hidden sector

International Nuclear Information System (INIS)

De Simone, Andrea

2010-04-01

Supersymmetric scenarios incorporating thermal leptogenesis as the origin of the observed matter-antimatter asymmetry generically predict abundances of the primordial elements which are in conflict with observations. In this paper we pro- pose a simple way to circumvent this tension and accommodate naturally ther- mal leptogenesis and primordial nucleosynthesis. We postulate the existence of a light hidden sector, coupled very weakly to the Minimal Supersymmetric Standard Model, which opens up new decay channels for the next-to-lightest supersymmetric particle, thus diluting its abundance during nucleosynthesis. We present a general model-independent analysis of this mechanism as well as two concrete realizations, and describe the relevant cosmological and astrophysical bounds and implications for this dark matter scenario. Possible experimental signatures at colliders and in cosmic-ray observations are also discussed. (orig.)

A K-theory anomaly free supersymmetric flipped SU(5) model from intersecting branes

Energy Technology Data Exchange (ETDEWEB)

Chen, C.-M. [George P. and Cynthia W. Mitchell Institute for Fundamental Physics, Texas A and M University, College Station, TX 77843 (United States)]. E-mail: cchen@physics.tamu.edu; Kraniotis, G.V. [George P. and Cynthia W. Mitchell Institute for Fundamental Physics, Texas A and M University, College Station, TX 77843 (United States)]. E-mail: kraniotis@physics.tamu.edu; Mayes, V.E. [George P. and Cynthia W. Mitchell Institute for Fundamental Physics, Texas A and M University, College Station, TX 77843 (United States)]. E-mail: eric@physics.tamu.edu; Nanopoulos, D.V. [George P. and Cynthia W. Mitchell Institute for Fundamental Physics, Texas A and M University, College Station, TX 77843 (United States) and Astroparticle Physics Group, Houston Advanced Research Center (HARC), Mitchell Campus, Woodlands, TX 77381 (United States) and Academy of Athens, Division of Natural Sciences, 28 Panepistimiou Avenue, Athens 10679 (Greece)]. E-mail: dimitri@physics.tamu.edu; Walker, J.W. [George P. and Cynthia W. Mitchell Institute for Fundamental Physics, Texas A and M University, College Station, TX 77843 (United States)]. E-mail: jwalker@physics.tamu.edu

2005-10-06

We construct an N=1 supersymmetric three-family flipped SU(5) model from type IIA orientifolds on T{sup 6}/(Z{sub 2}xZ{sub 2}) with D6-branes intersecting at general angles. The model is constrained by the requirement that Ramond-Ramond tadpoles cancel, the supersymmetry conditions, and that the gauge boson coupled to the U(1){sub X} factor does not get a string-scale mass via a generalised Green-Schwarz mechanism. The model is further constrained by requiring cancellation of K-theory charges. The spectrum contains a complete grand unified and electroweak Higgs sector, however the latter in a non-minimal number of copies. In addition, it contains extra matter both in bi-fundamental and vector-like representations as well as two copies of matter in the symmetric representation of SU(5)

Testing the AGN Unification Model in the Infrared

International Nuclear Information System (INIS)

Ramos Almeida, C; Levenson, N A; Radomski, J T; Alonso-Herrero, A; Asensio Ramos, A; Rodríguez Espinosa, J M; Pérez García, A M; Packham, C; Mason, R; Díaz-Santos, T

2012-01-01

We present near-to-mid-infrared spectral energy distributions (SEDs) for 21 Seyfert galaxies, using subarcsecond resolution imaging data. Our aim is to compare the properties Seyfert 1 (Sy1) and Seyfert 2 (Sy2) tori using clumpy torus models and a Bayesian approach to fit the infrared (IR) nuclear SEDs. These dusty tori have physical sizes smaller than 6 pc radius, as derived from our fits. Active galactic nuclei (AGN) unification schemes account for a variety of observational differences in terms of viewing geometry. However, we find evidence that strong unification may not hold, and that the immediate dusty surroundings of Sy1 and Sy2 nuclei are intrinsically different. The Type 2 tori studied here are broader, have more clumps, and these clumps have lower optical depths than those of Type 1 tori. The larger the covering factor of the torus, the smaller the probability of having direct view of the AGN, and vice-versa. In our sample, Sy2 tori have larger covering factors (C T = 0.95±0.02) and smaller escape probabilities than those of Sy1 (C T = 0.5±0.1). Thus, on the basis of the results presented here, the classification of a Seyfert galaxy may depend more on the intrinsic properties of the torus rather than on its mere inclination, in contradiction with the simplest unification model.

SO(14) unification of 3+1 families

International Nuclear Information System (INIS)

Karadayi, H.R.

1982-03-01

It is shown that the unification of 3+1 families is possible within the framework of 64 dimensional spinor representation of SO(14). Special care is given for a description without the heavy excess fermions such as conjugate and mirror or completely exotic fermions of some family unification schemes. With the aid of an intrinsic ''L-R Asymmetry'' mechanism which we proposed recently, the conventional strong and electromagnetic interactions are obtained for all four families by concentrating only on the symmetry breaking SO(14) → SU(3)sub(c) x U(1)sub(e.m.). However, the conventional weak interactions of the first three families are obtained just as in the standard SU(2)sub(L) x U(1)sub(Y) model, while those of the prescribed fourth family show certain differences. This is what we mean by 3+1 family unification. All vector particles mediating strong, electromagnetic and weak interactions which are the subjects of present phenomenological tests are specified among the vector fields of SO(14) and their mass mechanisms leading to a consistent description of this low-energy phenomenology are studied with the aid of the Higgs multiplets 14, 364, 1716 and 2002 of SO(14). Moreover, the fermion mass mechanisms are considered with the aid of these scalar multiplets and the contributions from these scalars to the vector and fermion masses are explicitly calculated. All these calculations are carried out in the new mathematical technique for the Lie algebra representations which we introduced recently. (author)

Duality and supersymmetric monopoles

International Nuclear Information System (INIS)

Gauntlett, J.P.

1998-01-01

Exact duality in supersymmetric gauge theories leads to highly non-trivial predictions about the moduli spaces of BPS monopole solutions. These notes attempt to be a pedagogical review of the current status of these investigations. (orig.)

The transformations between N= 2 supersymmetric Korteweg-de Vries and Harry Dym equations

International Nuclear Information System (INIS)

Tian Kai; Liu, Q. P.

2012-01-01

The N= 2 supercomformal transformations are employed to study supersymmetric integrable systems. It is proved that two known N= 2 supersymmetric Harry Dym equations are transformed into two N= 2 supersymmetric modified Korteweg-de Vries equations, thus are connected with two N= 2 supersymmetric Korteweg-de Vries equations.

Symmetries of supersymmetric integrable hierarchies of KP type

International Nuclear Information System (INIS)

Nissimov, E.; Pacheva, S.

2002-01-01

This article is devoted to the systematic study of additional (non-isospectral) symmetries of constrained (reduced) supersymmetric integrable hierarchies of KP type--the so-called SKP (R;M B ,M F ) models. The latter are supersymmetric extensions of ordinary constrained KP hierarchies which contain as special cases basic integrable systems such as (m)KdV, AKNS, Fordy-Kulish, Yajima-Oikawa, etc. As a first main result it is shown that any SKP (R;M B ,M F ) hierarchy possesses two different mutually (anti-)commuting types of superloop superalgebra additional symmetries corresponding to the positive- and negative-grade parts of certain superloop superalgebras. The second main result is the systematic construction of the full algebra of additional Virasoro symmetries of SKP (R;M B ,M F ) hierarchies, which requires nontrivial modifications of the Virasoro flows known from the general case of unconstrained Manin-Radul super-KP hierarchies (the latter flows do not define symmetries for constrained SKP (R;M B ,M F ) hierarchies). As a third main result we provide systematic construction of the supersymmetric analogs of multi-component (matrix) KP hierarchies and show that the latter contain, among others, the supersymmetric version of the Davey-Stewartson system. Finally, we present an explicit derivation of the general Darboux-Baecklund solutions for the SKP (R;M B ,M F ) super-tau functions (supersymmetric 'soliton'-like solutions) which preserve the additional (non-isospectral) symmetries

Phenomenological supersymmetry

International Nuclear Information System (INIS)

Zwirner, F.

1992-01-01

The motivations for low-energy supersymmetry and the main features of the minimal supersymmetric extension of the Standard Model are reviewed. Possible non-minimal models and the issue of gauge coupling unification are also discussed. Theoretical results relevant for supersymmetric particle searches at present and future accelerators are presented. In particular, recent results on radiative corrections to supersymmetric Higgs boson masses and couplings are summarized, and their implications for experimental searches are discussed in some detail. (author). 87 refs, 9 figs

Dispersive and damping properties of supersymmetric sound. 2

International Nuclear Information System (INIS)

Lebedev, V.V.; Smilga, A.V.

1988-01-01

This paper is the second part of the work devoted to the massless fermionic collective excitation in supersymmetric media at nonzero temperature. The solution to generalized kinetic equations for the Wess-Zumino model at low temperatures is presented and the situation at high temperatures is discussed. Supersymmetric gauge models are also discussed

Calabi-Yau compactifications of non-supersymmetric heterotic string theory

International Nuclear Information System (INIS)

Blaszczyk, Michael; Groot Nibbelink, Stefan

2015-07-01

Phenomenological explorations of heterotic strings have conventionally focused primarily on the E 8 x E 8 theory. We consider smooth compactifications of all three ten-dimensional heterotic theories to exhibit the many similarities between the non-supersymmetric SO(16) x SO(16) theory and the related supersymmetric E 8 x E 8 and SO(32) theories. In particular, we exploit these similarities to determine the bosonic and fermionic spectra of Calabi-Yau compactifications with line bundles of the nonsupersymmetric string. We use elements of four-dimensional supersymmetric effective field theory to characterize the non-supersymmetric action at leading order and determine the Green-Schwarz induced axion-couplings. Using these methods we construct a non-supersymmetric Standard Model(SM)-like theory. In addition, we show that it is possible to obtain SM-like models from the standard embedding using at least an order four Wilson line. Finally, we make a proposal of the states that live on five branes in the SO(16) x SO(16) theory and find under certain assumptions the surprising result that anomaly factorization only admits at most a single brane solution.

Supersymmetric self-dual Yang-Mills fields

International Nuclear Information System (INIS)

Zhao Liu

1994-01-01

A new four dimensional (4d) N = 1 supersymmetric integrable model, i.e. the supersymmetric self-dual Yang-Mills model is constructed. The equations of motion for this model are shown to be equivalent to the zero curvature condition on some superplane in the 4d superspace, the superplane being characterized by a point in the project space CP 3,4 . The linear systems are established according to this geometrical interpretation, and the effective action is also proposed in order to explain the dynamical content of the model

Supersymmetric axial anomalies and the Wess-Zumino action

International Nuclear Information System (INIS)

Harada, K.; Shizuya, K.

1988-01-01

We derive, by an algebraic method, a manifestly supersymmetric extension of Bardeen's minimal form of axial anomalies, which obeys the Wess-Zumino consistency condition. The left-right symmetric form of the anomalies is also obtained by a reduction procedure. We construct the supersymmetric Wess-Zumino effective action and study its low-energy features. (orig.)

Dark matter asymmetry in supersymmetric Dirac leptogenesis

International Nuclear Information System (INIS)

Choi, Ki-Young; Chun, Eung Jin; Shin, Chang Sub

2013-01-01

We discuss asymmetric or symmetric dark matter candidate in the supersymmetric Dirac leptogenesis scenario. By introducing a singlet superfield coupling to right-handed neutrinos, the overabundance problem of dark matter can be evaded and various possibilities for dark matter candidate arise. If the singlino is the lightest supersymmetric particle (LSP), it becomes naturally asymmetric dark matter. On the other hand, the right-handed sneutrino is a symmetric dark matter candidate whose relic density can be determined by the usual thermal freeze-out process. The conventional neutralino or gravitino LSP can be also a dark matter candidate as its non-thermal production from the right-handed sneutrino can be controlled appropriately. In our scenario, the late-decay of heavy supersymmetric particles mainly produces the right-handed sneutrino and neutrino which is harmless to the standard prediction of the Big-Bang Nucleosynthesis

Explanatory Unification by Proofs in School Mathematics

Science.gov (United States)

Komatsu, Kotaro; Fujita, Taro; Jones, Keith; Naoki, Sue

2018-01-01

Kitcher's idea of 'explanatory unification', while originally proposed in the philosophy of science, may also be relevant to mathematics education, as a way of enhancing student thinking and achieving classroom activity that is closer to authentic mathematical practice. There is, however, no mathematics education research treating explanatory…

Supersymmetric models with light higgsinos

International Nuclear Information System (INIS)

Bruemmer, F.

2012-05-01

In the Minimal Supersymmetric Standard Model, the higgsinos can have masses around the electroweak scale, while the other supersymmetric particles have TeV-scale masses. This happens in models of gauge-mediated SUSY breaking with a high messenger scale, which are motivated from string theory. For particular choices of the messenger eld content, multi-TeV squark and gluino masses naturally lead to a much lower electroweak scale, somewhat similar to focus point supersymmetry. They also induce Higgs masses of 124-126 GeV, while making the discovery of supersymmetry at the LHC unlikely. The light higgsinos will be di cult to see at the LHC but may eventually be discovered at a linear collider.

Spontaneous baryogenesis in supersymmetric models

International Nuclear Information System (INIS)

Abel, S.A.; Cottingham, W.N.; Whittingham, I.B.

1993-01-01

In this paper we extent the results of previous work on spontaneous baryogenesis to general models involving charge-parity (CP) violation in the Higgs sector. We show how to deal with Chern-Simons terms appearing in the effective potential arising from phase changes in the vacuum expectation values of the Higgs fields. In particular, this enables us to apply this mechanism to general supersymmetric models including the minimal supersymmetric standard model, and the extended model with a gauge singlet. A comparison is made between this approach, and that in which one solves the equations of motion for Higgs winding modes. As anticipated in earlier work, the effect of the latter approach is found to be small. (Author)

Level comparison theorems and supersymmetric quantum mechanics

International Nuclear Information System (INIS)

Baumgartner, B.; Grosse, H.

1986-01-01

The sign of the Laplacian of the spherical symmetric potential determines the order of energy levels with the same principal Coulomb quantum number. This recently derived theorem has been generalized, extended and applied to various situations in particle, nuclear and atomic physics. Besides a comparison theorem the essential step was the use of supersymmetric quantum mechanics. Recently worked out applications of supersymmetric quantum mechanics to index problems of Dirac operators are mentioned. (Author)

1/N perturbation theory and quantum conservation laws for supersymmetrical chiral field. 2

International Nuclear Information System (INIS)

Aref'eva, I.Ya.; Krivoshchekov, V.K.; Medvedev, P.B.; Gosudarstvennyj Komitet Standartov Soveta Ministrov SSSR, Moscow; Gosudarstvennyj Komitet po Ispol'zovaniyu Atomnoj Ehnergii SSSR, Moscow. Inst. Teoreticheskoj i Ehksperimental'noj Fiziki)

1980-01-01

The renormalizability of the supersymmetric chiral model (supersymmetric nonlinear σ-model) is proved in the framework of the 1/N perturbation theory expansion proposed in the previous paper. The renormalizability proof is essentially based on the quantum supersymmetric chirality condition. The supersymmetric formulation of equations of motion is given. The first non-trivial quantum conservation laws are derived

Supersymmetric extensions of Schrodinger-invariance

International Nuclear Information System (INIS)

Henkel, Malte; Unterberger, Jeremie

2006-01-01

The set of dynamic symmetries of the scalar free Schrodinger equation in d space dimensions gives a realization of the Schrodinger algebra that may be extended into a representation of the conformal algebra in d+2 dimensions, which yields the set of dynamic symmetries of the same equation where the mass is not viewed as a constant, but as an additional coordinate. An analogous construction also holds for the spin-12 Levy-Leblond equation. An N=2 supersymmetric extension of these equations leads, respectively, to a 'super-Schrodinger' model and to the (3 vertical bar 2)-supersymmetric model. Their dynamic supersymmetries form the Lie superalgebras osp(2 vertical bar 2)-bar sh(2 vertical bar 2) and osp(2 vertical bar 4), respectively. The Schrodinger algebra and its supersymmetric counterparts are found to be the largest finite-dimensional Lie subalgebras of a family of infinite-dimensional Lie superalgebras that are systematically constructed in a Poisson algebra setting, including the Schrodinger-Neveu-Schwarz algebra sns (N) with N supercharges. Covariant two-point functions of quasiprimary superfields are calculated for several subalgebras of osp(2 vertical bar 4). If one includes both N=2 supercharges and time-inversions, then the sum of the scaling dimensions is restricted to a finite set of possible values

Families in the nonperturbative unification scheme

Energy Technology Data Exchange (ETDEWEB)

Kapetanakis, D. (National Research Centre for the Physical Sciences Democritos, Athens (Greece)); Theisen, S. (European Organization for Nuclear Research, Geneva (Switzerland)); Zoupanos, G. (Ethnikon Metsovion Polytechneion, Athens (Greece). Dept. of Physics)

1989-10-12

Within the nonperturbative unification framework of Maiani, Parisi and Petronzio, we examine the influence of the number of fermion and Higgs families, when they are grouped in representations of horizontal family groups, on the low energy couplings of the standard model. In this way we find a number of new phenomenologically acceptable solutions for the standard model's low energy couplings. (orig.).

Families in the nonperturbative unification scheme

International Nuclear Information System (INIS)

Kapetanakis, D.; Theisen, S.; Zoupanos, G.

1989-01-01

Within the nonperturbative unification framework of Maiani, Parisi and Petronzio, we examine the influence of the number of fermion and Higgs families, when they are grouped in representations of horizontal family groups, on the low energy couplings of the standard model. In this way we find a number of new phenomenologically acceptable solutions for the standard model's low energy couplings. (orig.)

Authenticity and Unification in Quechua Language Planning.

Science.gov (United States)

Hornberger, Nancy H.; King, Kendall

1998-01-01

Examines the potentially problematic tension between the goals of authenticity and unification in Quechua-language planning. One case study examines the orthographic debate that arose in Peru, and the second case study concerns two indigenous communities in Saraguro in the Southern Ecuadorian highlands where Spanish predominates but two Quichua…

Supersymmetric U boson and the old U(1) problem

International Nuclear Information System (INIS)

Kim, B.R.

1983-01-01

In the supersymmetric SU(3)xSU(2)xU(1)xUsup(')(1) model the new gauge group Usup(')(1) enforces the introduction of mirror fermions. In this note we address the inverse question. If one starts with SU(3)xSU(2)xU(1) including mirror fermions, what physical arguments other than the supersymmetric require the introduction of a new gauge group Usup(')(1). It turns out that the old U(1) problem is closely related with this question. Further we give an estimate for the upper bound for the parameter of the supersymmetric U boson r and x. (orig.)

Flavour changing decays of Z0 in supersymmetric models

International Nuclear Information System (INIS)

Gamberini, G.; Ridolfi, G.

1987-01-01

The possible existence of detectable flavour-changing branching modes of the Z 0 boson is examined in the context of supersymmetric models of currrent interest. An explicit calculation shows that in the so-called minimal version of the supersymmetric standard model the branching ratios for Z 0 →banti s or tanti c are not larger than in the standard model itself and are as such unobservable. On the contrary, we find that in a recently proposed extension of the supersymmetric standard model the mode Z 0 →tanti c may be at the order of being detectable. (orig.)

Vacuum fluctuations of the supersymmetric field in curved background

International Nuclear Information System (INIS)

Bilić, Neven; Domazet, Silvije; Guberina, Branko

2012-01-01

We study a supersymmetric model in curved background spacetime. We calculate the effective action and the vacuum expectation value of the energy momentum tensor using a covariant regularization procedure. A soft supersymmetry breaking induces a nonzero contribution to the vacuum energy density and pressure. Assuming the presence of a cosmic fluid in addition to the vacuum fluctuations of the supersymmetric field an effective equation of state is derived in a self-consistent approach at one loop order. The net effect of the vacuum fluctuations of the supersymmetric fields in the leading adiabatic order is a renormalization of the Newton and cosmological constants.

Vacuum fluctuations of the supersymmetric field in curved background

Energy Technology Data Exchange (ETDEWEB)

Bilic, Neven, E-mail: bilic@thphys.irb.hr [Rudjer Boskovic Institute, POB 180, HR-10002 Zagreb (Croatia); Domazet, Silvije, E-mail: sdomazet@irb.hr [Rudjer Boskovic Institute, POB 180, HR-10002 Zagreb (Croatia); Guberina, Branko, E-mail: guberina@thphys.irb.hr [Rudjer Boskovic Institute, POB 180, HR-10002 Zagreb (Croatia)

2012-01-16

We study a supersymmetric model in curved background spacetime. We calculate the effective action and the vacuum expectation value of the energy momentum tensor using a covariant regularization procedure. A soft supersymmetry breaking induces a nonzero contribution to the vacuum energy density and pressure. Assuming the presence of a cosmic fluid in addition to the vacuum fluctuations of the supersymmetric field an effective equation of state is derived in a self-consistent approach at one loop order. The net effect of the vacuum fluctuations of the supersymmetric fields in the leading adiabatic order is a renormalization of the Newton and cosmological constants.

Supersymmetric deformations of 3D SCFTs from tri-Sasakian truncation

Energy Technology Data Exchange (ETDEWEB)

Karndumri, Parinya [Chulalongkorn University, String Theory and Supergravity Group, Department of Physics, Faculty of Science, Bangkok (Thailand)

2017-02-15

We holographically study supersymmetric deformations of N = 3 and N = 1 superconformal field theories in three dimensions using four-dimensional N = 4 gauged supergravity coupled to three-vector multiplets with non-semisimple SO(3) x (T{sup 3},T{sup 3}) gauge group. This gauged supergravity can be obtained from a truncation of 11-dimensional supergravity on a tri-Sasakian manifold and admits both N = 1,3 supersymmetric and stable non-supersymmetric AdS{sub 4} critical points. We analyze the BPS equations for SO(3) singlet scalars in detail and study possible supersymmetric solutions. A number of RG flows to non-conformal field theories and half-supersymmetric domain walls are found, and many of them can be given analytically. Apart from these ''flat'' domain walls, we also consider AdS{sub 3}-sliced domain wall solutions describing two-dimensional conformal defects with N = (1,0) supersymmetry within the dual N = 1 field theory while this type of solutions does not exist in the N = 3 case. (orig.)

Unification, small and large

Energy Technology Data Exchange (ETDEWEB)

Fritzsch, Harald

1993-04-15

Full text: Fruitful exchanges between particle physics, astrophysics and cosmology have become a common feature in the last decade. In January, Coral Gables near Miami was the stage for a 'Unified Symmetry in the Small and the Large' meeting. Coral Gables is a famous physics venue. In January 1964, the year that the quark model of hadrons emerged, Behram Kursunoglu initiated a series of particle physics meetings that continued for 20 years and formed a regular focus for this development. The final such meeting was in 1983, coinciding with both the 80th birthday of field theory pioneer Paul Dirac, who worked in Florida towards the end of his career, and the discovery of the W bosons at CERN. The resurrected Coral Gables meeting began with historical accounts of the emergence of Big Bang cosmology, by Robert Ralph and Herman Alpher, while Andrei Linde proposed our expanding universe as a small part of a stationary system, infinite both in space and in time. The observational status of Big Bang cosmology was reviewed by Bruce Partridge, John Mather and Martin Harwit, emphasizing the cosmic background radiation, where temperature is now measured by the COBE satellite detectors to 2.726 ± 0.01 OK. The tiny fluctuations observed by COBE pose problems for standard cold dark matter models. Edward ('Rocky') Kolb reported on new studies on the electroweak phase transition, based on an analogy with the physics of liquid crystals. Richard Holman discussed the fate of global symmetries at energies near the Planck (grand unification) energy, and Paul Steinhardt talked about tensorial and scalar metric fluctuations in the light of the COBE results. Anthony Tyson gave an impressive description of dark matter studies using gravitational lensing, now emerging as a unique tool for indirectly observing intervening dark matter. A neutrino mass of 10 electronvolts could account for observed dark matter distributions, but fails to provide the necessary seeds for galaxy formation. A

Unification, small and large

International Nuclear Information System (INIS)

Fritzsch, Harald

1993-01-01

Full text: Fruitful exchanges between particle physics, astrophysics and cosmology have become a common feature in the last decade. In January, Coral Gables near Miami was the stage for a 'Unified Symmetry in the Small and the Large' meeting. Coral Gables is a famous physics venue. In January 1964, the year that the quark model of hadrons emerged, Behram Kursunoglu initiated a series of particle physics meetings that continued for 20 years and formed a regular focus for this development. The final such meeting was in 1983, coinciding with both the 80th birthday of field theory pioneer Paul Dirac, who worked in Florida towards the end of his career, and the discovery of the W bosons at CERN. The resurrected Coral Gables meeting began with historical accounts of the emergence of Big Bang cosmology, by Robert Ralph and Herman Alpher, while Andrei Linde proposed our expanding universe as a small part of a stationary system, infinite both in space and in time. The observational status of Big Bang cosmology was reviewed by Bruce Partridge, John Mather and Martin Harwit, emphasizing the cosmic background radiation, where temperature is now measured by the COBE satellite detectors to 2.726 ± 0.01 OK. The tiny fluctuations observed by COBE pose problems for standard cold dark matter models. Edward ('Rocky') Kolb reported on new studies on the electroweak phase transition, based on an analogy with the physics of liquid crystals. Richard Holman discussed the fate of global symmetries at energies near the Planck (grand unification) energy, and Paul Steinhardt talked about tensorial and scalar metric fluctuations in the light of the COBE results. Anthony Tyson gave an impressive description of dark matter studies using gravitational lensing, now emerging as a unique tool for indirectly observing intervening dark matter. A neutrino mass of 10 electronvolts could account for observed dark matter distributions, but fails to provide the necessary seeds for

Supersymmetric symplectic quantum mechanics

Science.gov (United States)

de Menezes, Miralvo B.; Fernandes, M. C. B.; Martins, Maria das Graças R.; Santana, A. E.; Vianna, J. D. M.

2018-02-01

Symplectic Quantum Mechanics SQM considers a non-commutative algebra of functions on a phase space Γ and an associated Hilbert space HΓ to construct a unitary representation for the Galilei group. From this unitary representation the Schrödinger equation is rewritten in phase space variables and the Wigner function can be derived without the use of the Liouville-von Neumann equation. In this article we extend the methods of supersymmetric quantum mechanics SUSYQM to SQM. With the purpose of applications in quantum systems, the factorization method of the quantum mechanical formalism is then set within supersymmetric SQM. A hierarchy of simpler hamiltonians is generated leading to new computation tools for solving the eigenvalue problem in SQM. We illustrate the results by computing the states and spectra of the problem of a charged particle in a homogeneous magnetic field as well as the corresponding Wigner function.

Aspects of the supersymmetric Goldstone formalism

International Nuclear Information System (INIS)

Lerche, W.

1985-01-01

The present thesis deal with the discussion of general properties of Goldstone excitations in global N=1 supersymmetric theories. The results can become relevant in the framework of theories which interpret quarks and leptons as composite 'quasi-Goldstone fermions'. The thesis is arranged in two main parts: the first is occupied by group-theoretical aspects, i.e. by the spectrum of supersymmetric Goldstone excitations as well as by geometrical considerations which are connected with effective Lagrangian densities. In the second main part dynamic questions like for instance mass generation are treated. For this a suitable formalism is developed. (orig.) [de

Supersymmetric reflection matrices

International Nuclear Information System (INIS)

Moriconi, M.; Schoutens, K.

1997-04-01

We briefly review the general structure of integrable particle theories in 1 + 1 dimensions having N = 1 supersymmetry. Examples are specific perturbed superconformal field theories (of Yang-Lee type) and the N = 1 supersymmetric sine-Gordon theory. We comment on the modifications that are required when the N = 1 supersymmetry algebra contains non-trivial topological charges. (author). 8 refs, 2 figs

Quantum gravity

International Nuclear Information System (INIS)

Isham, C.

1989-01-01

Gravitational effects are seen as arising from a curvature in spacetime. This must be reconciled with gravity's apparently passive role in quantum theory to achieve a satisfactory quantum theory of gravity. The development of grand unified theories has spurred the search, with forces being of equal strength at a unification energy of 10 15 - 10 18 GeV, with the ''Plank length'', Lp ≅ 10 -35 m. Fundamental principles of general relativity and quantum mechanics are outlined. Gravitons are shown to have spin-0, as mediators of gravitation force in the classical sense or spin-2 which are related to the quantisation of general relativity. Applying the ideas of supersymmetry to gravitation implies partners for the graviton, especially the massless spin 3/2 fermion called a gravitino. The concept of supersymmetric strings is introduced and discussed. (U.K.)

Indexes to Volume 54

Indian Academy of Sciences (India)

Rapid Communication ... Bulk viscosity of strange quark matter in density dependent quark mass model ... Supersymmetric unification in the light of neutrino mass ... Estimation of light transport parameters in biological media using coherent.

Non-perturbative supersymmetry anomaly in supersymmetric QCD

International Nuclear Information System (INIS)

Shamir, Y.

1991-03-01

The zero modes of the Dirac operator in an instanton and other topologically non-trivial backgrounds are unstable in a large class of massless or partially massless supersymmetric gauge theories. We show that under a generic perturbation of the scalar fields all zero modes become resonances, and discuss the ensuing breakdown of conventional perturbation theory. As a result, despite of the presence of massless fermions, the field theoretic tunneling amplitude is not suppressed. In massless supersymmetric QCD with N c ≤ N f the effective potential is found to be negative and monotonically increasing in the weak coupling regime for scalar VEVs which lie on the perturbatively flat directions. Consequently, massless supersymmetric QCD with N c ≤ N f exhibits a non-perturbative supersymmetry anomaly and exists in a strongly interacting phase which closely resembles ordinary QCD. The same conclusions apply if small masses are added to the lagrangian and the massless limit is smooth. (author). 21 refs, 5 figs

Two- and three dimensional electrons and photons and their supersymmetric partners

International Nuclear Information System (INIS)

Steringa, J.J.

1989-01-01

This thesis contains a study of supersymmetric gauge theories in two and tree spacetime dimensions. Supersymmetric gauge theories in less than four spacetime dimensions are useful for trying out field theoretical methods which ultimately will be applied to realistic models. In ch. 1 all the aspects of field theory that are necessary for later chapters are treated. In ch. 2 sypersymmetry in two- and three-dimensional space time is treated, and superfields and superspace techniques are introduced. With these a simple Abelian supersymmetric gauge theory in two spacetime dimensions is constructed, the Schwinger model. Ch. 3 deals with general properties and a perturbative analysis of the model. Ch. 4 contains a non-perturbative analysis by means of Dyson-Schwinger equations. A supersummetric extension of theSalam-Delbourgo Gauge Technique is presented and is applied with some seccess to the supersymmetric Schwinger model. In ch. 5 prperties of three-dimensional supersymmetric gauge theories are investigated. (author). 55 refs.; 7 figs.; schemes

Invariant solutions of the supersymmetric sine-Gordon equation

International Nuclear Information System (INIS)

Grundland, A M; Hariton, A J; Snobl, L

2009-01-01

A comprehensive symmetry analysis of the N=1 supersymmetric sine-Gordon equation is performed. Two different forms of the supersymmetric system are considered. We begin by studying a system of partial differential equations corresponding to the coefficients of the various powers of the anticommuting independent variables. Next, we consider the super-sine-Gordon equation expressed in terms of a bosonic superfield involving anticommuting independent variables. In each case, a Lie (super)algebra of symmetries is determined and a classification of all subgroups having generic orbits of codimension 1 in the space of independent variables is performed. The method of symmetry reduction is systematically applied in order to derive invariant solutions of the supersymmetric model. Several types of algebraic, hyperbolic and doubly periodic solutions are obtained in explicit form.

Globally and locally supersymmetric effective theories for light fields

International Nuclear Information System (INIS)

Brizi, Leonardo; Gomez-Reino, Marta; Scrucca, Claudio A.

2009-01-01

We reconsider the general question of how to characterize most efficiently the low-energy effective theory obtained by integrating out heavy modes in globally and locally supersymmetric theories. We consider theories with chiral and vector multiplets and identify the conditions under which an approximately supersymmetric low-energy effective theory can exist. These conditions translate into the requirements that all the derivatives, fermions and auxiliary fields should be small in units of the heavy mass scale. They apply not only to the matter sector, but also to the gravitational one if present, and imply in that case that the gravitino mass should be small. We then show how to determine the unique exactly supersymmetric theory that approximates this effective theory at the lowest order in the counting of derivatives, fermions and auxiliary fields, by working both at the superfield level and with component fields. As a result we give a simple prescription for integrating out heavy superfields in an algebraic and manifestly supersymmetric way, which turns out to hold in the same form both for globally and locally supersymmetric theories, meaning that the process of integrating out heavy modes commutes with the process of switching on gravity. More precisely, for heavy chiral and vector multiplets one has to impose respectively stationarity of the superpotential and the Kaehler potential.

Indirect detection of heavy supersymmetric dark matter

International Nuclear Information System (INIS)

Kamionkowski, M.

1991-02-01

If neutralinos reside in the galactic halo they will be captured in the Sun and annihilate therein producing high-energy neutrinos. Present limits on the flux of such neutrinos from underground detectors such as IMB and Kamiokande 2 may be used to rule out certain supersymmetric dark-matter candidates, while in many other supersymmetric models the rates are large enough that if neutralinos do reside in the galactic halo, observation of a neutrino signal may be possible in the near future. 10 refs., 2 figs

Unification types of housing during Sochi Olympics

Directory of Open Access Journals (Sweden)

Aleksandr A. Babaev

2011-05-01

Full Text Available In the article the statement of the unification problem of housing accommodation of participants, spectators, staff, committee during the Winter Olympics in Sochi. We give a mathematical formalization of the problem, where the unknown variables are theelements of the combination of types of accommodation sorted by the level of comfortand representation.

(4,0) supersymmetric sigma-model and t-duality

International Nuclear Information System (INIS)

Lhallabi, T.

1997-08-01

The conserved supercurrents J ++ and J -- are deduced for the (4,0) supersymmetric sigma model on harmonic superspace with arbitrary background gauge connection. These are introduced in the Lagrangian density of the model by their couplings to the analytic gauge superfields Γ -- and Γ ++ . The T-duality transformations are obtained by integrating out the analytic gauge superfields. Finally the (4,0) supersymmetric anomaly is derived. (author). 20 refs

Three-body Supersymmetric Top Decays

CERN Document Server

Belyaev, A; Lola, S; Belyaev, Alexander; Ellis, John; Lola, Smaragda

2000-01-01

We discuss three-body supersymmetric top decays, in schemes both with andwithout R-parity conservation, assuming that sfermion masses are larger thanm_t. We find that MSSM top decays into chargino/neutralino pairs have a strongkinematic suppression in the region of the supersymmetric parameter spaceconsistent with the LEP limits, with a decay width =< 10^{-5} GeV. MSSM topdecays into neutralino pairs have less kinematical suppression, but require aflavour-changing vertex, and are likely to have a smaller rate. On the otherhand, R-violating decays to single charginos, neutralinos and conventionalfermions can be larger for values of the R-violating couplings still permittedby other upper limits. The cascade decays of the charginos and neutralinos maylead to spectacular signals with explicit lepton-number violation, such aslike-sign lepton events.

Extended N=2 supersymmetric matrix (1, s)-KdV hierarchies

International Nuclear Information System (INIS)

Krivonos, S.O.; Sorin, A.S.

1997-01-01

We propose the Lax operators for N=2 supersymmetric matrix generalization of the bosonic (1, s)-KdV hierarchies. The simplest examples - the N=2 supersymmetric a=4 KdV and a=5/2 Boussinesq hierarchies - are discussed in detail

On the stochastic structure of globally supersymmetric field theories

International Nuclear Information System (INIS)

Flume, R.; Lechtenfeld, O.

1983-09-01

We reformulate the bosonic sector of globally supersymmetric field theories through a ''fermionisation'' of bosonic Feynman graphs. The recipe for the fermionisation gives an explicit realisation of the Nicolai map. The graphical rules for supersymmetric Yang-Mills fields in the reformulated version turn out to be simpler than those of ordinary Yang-Mills fields. (orig.)

One-instanton calculations in N=2 supersymmetric gauge theories

International Nuclear Information System (INIS)

Ito, Katsushi

1998-01-01

We study the low-energy effective action of N=2 supersymmetric gauge theories in the Coulomb branch. Using microscopic instanton calculus, we compute the one-instanton contribution to the pre potential for N=2 supersymmetric SU(N c ) Yang-Mills theory. We show that the microscopic result agrees with the exact solution. (Author). 23 refs

On the supersymmetrization of Galileon theories in four dimensions

Science.gov (United States)

Elvang, Henriette; Hadjiantonis, Marios; Jones, Callum R. T.; Paranjape, Shruti

2018-06-01

We use on-shell amplitude techniques to study the possible N = 1 supersymmetrizations of Galileon theories in 3 + 1 dimensions, both in the limit of decoupling from DBI and without. Our results are that (1) the quartic Galileon has a supersymmetrization compatible with Galileon shift symmetry (ϕ → ϕ + c +bμxμ) for the scalar sector and a constant shift symmetry (ψ → ψ + ξ) for the fermion sector, and it is unique at least at 6th order in fields, but possibly not beyond; (2) the enhanced "special Galileon" symmetry is incompatible with supersymmetry; (3) there exists a quintic Galileon with a complex scalar preserving Galileon shift symmetry; (4) one cannot supersymmetrize the cubic and quintic Galileon while preserving the Galileon shift symmetry for the complex scalar; and (5) for the quartic and quintic Galileon, we present evidence for a supersymmetrization in which the real Galileon scalar is partnered with an R-axion to form a complex scalar which only has an ordinary shift symmetry.

Principles of the Unification of Our Agency

Science.gov (United States)

Roth, Klas

2011-01-01

Do we need principles of the unification of our agency, our mode of acting? Immanuel Kant and Christine Korsgaard argue that the reflective structure of our mind forces us to have some conception of ourselves, others and the world--including our agency--and that it is through will and reason, and in particular principles of our agency, that we…

Classifying supersymmetric solutions in 3D maximal supergravity

Science.gov (United States)

de Boer, Jan; Mayerson, Daniel R.; Shigemori, Masaki

2014-12-01

String theory contains various extended objects. Among those, objects of codimension two (such as the D7-brane) are particularly interesting. Codimension-two objects carry non-Abelian charges which are elements of a discrete U-duality group and they may not admit a simple spacetime description, in which case they are known as exotic branes. A complete classification of consistent codimension-two objects in string theory is missing, even if we demand that they preserve some supersymmetry. As a step toward such a classification, we study the supersymmetric solutions of 3D maximal supergravity, which can be regarded as an approximate description of the geometry near codimension-two objects. We present a complete classification of the types of supersymmetric solutions that exist in this theory. We found that this problem reduces to that of classifying nilpotent orbits associated with the U-duality group, for which various mathematical results are known. We show that the only allowed supersymmetric configurations are 1/2, 1/4, 1/8, and 1/16 BPS, and determine the nilpotent orbits that they correspond to. One example of 1/16 BPS configurations is a generalization of the MSW system, where momentum runs along the intersection of seven M5-branes. On the other hand, it turns out exceedingly difficult to translate this classification into a simple criterion for supersymmetry in terms of the non-Abelian (monodromy) charges of the objects. For example, it can happen that a supersymmetric solution exists locally but cannot be extended all the way to the location of the object. To illustrate the various issues that arise in constructing supersymmetric solutions, we present a number of explicit examples.

Supersymmetric Higgs boson production in Z decays

International Nuclear Information System (INIS)

Gamberini, G.; Giudice, G.F.; Ridolfi, G.

1987-01-01

The problem of distinguishing between the standard model and the supersymmetric Higgs bosons is considered in the context of Z 0 decays. We find that, for some choices of the parameters, the branching ratio for Z 0 → H 0 γ is strongly enhanced by the exchange of supersymmetric fermions as virtual particles. This makes the study of this process at LEP very interesting, since other Z 0 branching modes into Higgs bosons, such as Z 0 → H 0 μ + μ - , are not so clearly modified by supersymmetry. (orig.)

Flavor hierarchy in SO(10) grand unified theories via 5-dimensional wave-function localization

Science.gov (United States)

Kitano, Ryuichiro; Li, Tianjun

2003-06-01

A mechanism to generate fermion-mass hierarchy in SO(10) grand unified theories is considered. We find that the lopsided family structure, which is suitable to the large angle Mikheyev-Smirnov-Wolfenstein solution to solar neutrino oscillation, is realized without introducing extra matter fields if the hierarchy originates from the wave-function profile in an extra dimension. Unlike the Froggatt-Nielsen mechanism, the SO(10) breaking effect may directly contribute to the source of the hierarchy, i.e., the bulk mass terms. It naturally explains the difference of the hierarchical patterns between the quark and the lepton sectors. We also find the possibility of horizontal unification, in which three generations of matter fields are unified to a 3-dimensional representation of an SU(2) gauge group.

Flavor hierarchy in SO(10) grand unified theories via 5-dimensional wave-function localization

International Nuclear Information System (INIS)

Kitano, Ryuichiro; Li Tianjun

2003-01-01

A mechanism to generate fermion-mass hierarchy in SO(10) grand unified theories is considered. We find that the lopsided family structure, which is suitable to the large angle Mikheyev-Smirnov-Wolfenstein solution to solar neutrino oscillation, is realized without introducing extra matter fields if the hierarchy originates from the wave-function profile in an extra dimension. Unlike the Froggatt-Nielsen mechanism, the SO(10) breaking effect may directly contribute to the source of the hierarchy, i.e., the bulk mass terms. It naturally explains the difference of the hierarchical patterns between the quark and the lepton sectors. We also find the possibility of horizontal unification, in which three generations of matter fields are unified to a 3-dimensional representation of an SU(2) gauge group

Contraction-based classification of supersymmetric extensions of kinematical lie algebras

International Nuclear Information System (INIS)

Campoamor-Stursberg, R.; Rausch de Traubenberg, M.

2010-01-01

We study supersymmetric extensions of classical kinematical algebras from the point of view of contraction theory. It is shown that contracting the supersymmetric extension of the anti-de Sitter algebra leads to a hierarchy similar in structure to the classical Bacry-Levy-Leblond classification.

N = 1 supersymmetric indices and the four-dimensional A-model

Science.gov (United States)

Closset, Cyril; Kim, Heeyeon; Willett, Brian

2017-08-01

We compute the supersymmetric partition function of N = 1 supersymmetric gauge theories with an R-symmetry on M_4\\cong M_{g,p}× {S}^1 , a principal elliptic fiber bundle of degree p over a genus- g Riemann surface, Σ g . Equivalently, we compute the generalized supersymmetric index I_{M}{_{g,p}, with the supersymmetric three-manifold M_{g,p} as the spatial slice. The ordinary N = 1 supersymmetric index on the round three-sphere is recovered as a special case. We approach this computation from the point of view of a topological A-model for the abelianized gauge fields on the base Σ g . This A-model — or A-twisted two-dimensional N = (2 , 2) gauge theory — encodes all the information about the generalized indices, which are viewed as expectations values of some canonically-defined surface defects wrapped on T 2 inside Σ g × T 2. Being defined by compactification on the torus, the A-model also enjoys natural modular properties, governed by the four-dimensional 't Hooft anomalies. As an application of our results, we provide new tests of Seiberg duality. We also present a new evaluation formula for the three-sphere index as a sum over two-dimensional vacua.

Deductive Synthesis of the Unification Algorithm,

Science.gov (United States)

1981-06-01

DEDUCTIVE SYNTHESIS OF THE I - UNIFICATION ALGORITHM Zohar Manna Richard Waldinger I F? Computer Science Department Artificial Intelligence Center...theorem proving," Artificial Intelligence Journal, Vol. 9, No. 1, pp. 1-35. Boyer, R. S. and J S. Moore [Jan. 19751, "Proving theorems about LISP...d’Intelligence Artificielle , U.E.R. de Luminy, Universit6 d’ Aix-Marseille II. Green, C. C. [May 1969], "Application of theorem proving to problem

Supersymmetric Higgs bosons and beyond

International Nuclear Information System (INIS)

Carena, Marcela; Kong, Kyoungchul; Ponton, Eduardo; Zurita, Jose

2010-01-01

We consider supersymmetric models that include particles beyond the minimal supersymmetric standard model (MSSM) with masses in the TeV range, and that couple significantly to the MSSM Higgs sector. We perform a model-independent analysis of the spectrum and couplings of the MSSM Higgs fields, based on an effective theory of the MSSM degrees of freedom. The tree-level mass of the lightest CP-even state can easily be above the LEP bound of 114 GeV, thus allowing for a relatively light spectrum of superpartners, restricted only by direct searches. The Higgs spectrum and couplings can be significantly modified compared to the MSSM ones, often allowing for interesting new decay modes. We also observe that the gluon fusion production cross section of the SM-like Higgs can be enhanced with respect to both the standard model and the MSSM.

IIB solutions with N>28 Killing spinors are maximally supersymmetric

International Nuclear Information System (INIS)

Gran, U.; Gutowski, J.; Papadopoulos, G.; Roest, D.

2007-01-01

We show that all IIB supergravity backgrounds which admit more than 28 Killing spinors are maximally supersymmetric. In particular, we find that for all N>28 backgrounds the supercovariant curvature vanishes, and that the quotients of maximally supersymmetric backgrounds either preserve all 32 or N<29 supersymmetries

arXiv B-branes and supersymmetric quivers in 2d

CERN Document Server

Closset, Cyril; Sharpe, Eric

2018-02-08

We study 2d $ \\mathcal{N} $ = (0, 2) supersymmetric quiver gauge theories that describe the low-energy dynamics of D1-branes at Calabi-Yau fourfold (CY$_{4}$) singularities. On general grounds, the holomorphic sector of these theories — matter content and (classical) superpotential interactions — should be fully captured by the topological B-model on the CY$_{4}$. By studying a number of examples, we confirm this expectation and flesh out the dictionary between B-brane category and supersymmetric quiver: the matter content of the supersymmetric quiver is encoded in morphisms between B-branes (that is, Ext groups of coherent sheaves), while the superpotential interactions are encoded in the A$_{∞}$ algebra satisfied by the morphisms. This provides us with a derivation of the supersymmetric quiver directly from the CY$_{4}$ geometry. We also suggest a relation between triality of $ \\mathcal{N} $ = (0,2) gauge theories and certain mutations of exceptional collections of sheaves. 0d $ \\mathcal{N} $ = 1 supe...

Supersymmetric versions of the Fokas–Gel’fand formula for immersion

International Nuclear Information System (INIS)

Bertrand, S; Grundland, A M

2016-01-01

In this paper, we construct and investigate two supersymmetric versions of the Fokas–Gel’fand formula for the immersion of 2D surfaces associated with a supersymmetric integrable system. The first version involves an infinitesimal deformation of the zero-curvature condition and the linear spectral problem associated with this system. This deformation leads the surfaces to be represented in terms of a bosonic supermatrix immersed in a Lie superalgebra. The second supersymmetric version is obtained by using a fermionic parameter deformation to construct surfaces expressed in terms of a fermionic supermatrix immersed in a Lie superalgebra. For both extensions, we provide a geometrical characterization of deformed surfaces using the super Killing form as an inner product and a super moving frame formalism. The theoretical results are applied to the supersymmetric sine-Gordon equation in order to construct super soliton surfaces associated with five different symmetries. We find integrated forms of these surfaces which represent constant Gaussian curvature surfaces and nonlinear Weingarten-type surfaces. (paper)

Basic hypergeometry of supersymmetric dualities

Energy Technology Data Exchange (ETDEWEB)

Gahramanov, Ilmar, E-mail: ilmar.gahramanov@aei.mpg.de [Max Planck Institute for Gravitational Physics (Albert Einstein Institute), Am Mühlenberg 1, D14476 Potsdam (Germany); Institut für Physik und IRIS Adlershof, Humboldt-Universität zu Berlin, Zum Grossen Windkanal 6, D12489 Berlin (Germany); Institute of Radiation Problems ANAS, B.Vahabzade 9, AZ1143 Baku (Azerbaijan); Department of Mathematics, Khazar University, Mehseti St. 41, AZ1096, Baku (Azerbaijan); Rosengren, Hjalmar, E-mail: hjalmar@chalmers.se [Department of Mathematical Sciences, Chalmers University of Technology and University of Gothenburg, SE-412 96 Göteborg (Sweden)

2016-12-15

We introduce several new identities combining basic hypergeometric sums and integrals. Such identities appear in the context of superconformal index computations for three-dimensional supersymmetric dual theories. We give both analytic proofs and physical interpretations of the presented identities.

Algebraic renormalization of supersymmetric gauge theories with dimensionful parameters

International Nuclear Information System (INIS)

Golterman, Maarten; Shamir, Yigal

2010-01-01

It is usually believed that there are no perturbative anomalies in supersymmetric gauge theories beyond the well-known chiral anomaly. In this paper we revisit this issue, because previously given arguments are incomplete. Specifically, we rule out the existence of soft anomalies, i.e., quantum violations of supersymmetric Ward identities proportional to a mass parameter in a classically supersymmetric theory. We do this by combining a previously proven theorem on the absence of hard anomalies with a spurion analysis, using the methods of algebraic renormalization. We work in the on-shell component formalism throughout. In order to deal with the nonlinearity of on-shell supersymmetry transformations, we take the spurions to be dynamical, and show how they nevertheless can be decoupled.

Generalized supersymmetric cosmological term in N=1 supergravity

Energy Technology Data Exchange (ETDEWEB)

Concha, P.K.; Rodríguez, E.K. [Departamento de Física, Universidad de Concepción,Casilla 160-C, Concepción (Chile); Dipartimento di Scienza Applicata e Tecnologia (DISAT), Politecnico di Torino,Corso Duca degli Abruzzi 24, I-10129 Torino (Italy); Istituto Nazionale di Fisica Nucleare (INFN) Sezione di Torino,Via Pietro Giuria 1, 10125 Torino (Italy); Salgado, P. [Departamento de Física, Universidad de Concepción,Casilla 160-C, Concepción (Chile)

2015-08-04

An alternative way of introducing the supersymmetric cosmological term in a supergravity theory is presented. We show that the AdS-Lorentz superalgebra allows to construct a geometrical formulation of supergravity containing a generalized supersymmetric cosmological constant. The N=1, D=4 supergravity action is built only from the curvatures of the AdS-Lorentz superalgebra and corresponds to a MacDowell-Mansouri like action. The extension to a generalized AdS-Lorentz superalgebra is also analyzed.

Unification of Forces: The Road to Jointness?

Science.gov (United States)

1991-05-15

tend to resist large change--or innovation. Because organizations value "predictability, stability, and certainty," incremental change is the...preferred mode of behavior for organizations.29 Unification of the forces would be a large, rather than an incremental , change; thus, the services would...coordinating planning and bidgeting , providing unified direction, accounting and controlling weapons and equipment acquisition, eliminating duplication of

Quantum gravity unification via transfinite arithmetic and geometrical averaging

International Nuclear Information System (INIS)

El Naschie, M.S.

2008-01-01

In E-Infinity theory, we have not only infinitely many dimensions but also infinitely many fundamental forces. However, due to the hierarchical structure of ε (∞) spacetime we have a finite expectation number for its dimensionality and likewise a finite expectation number for the corresponding interactions. Starting from the preceding fundamental principles and using the experimental findings as well as the theoretical value of the coupling constants of the electroweak and the strong forces we present an extremely simple averaging procedure for determining the quantum gravity unification coupling constant with and without super symmetry. The work draws heavily on previous results, in particular a paper, by the Slovian Prof. Marek-Crnjac [Marek-Crnjac L. On the unification of all fundamental forces in a fundamentally fuzzy Cantorian ε (∞) manifold and high energy physics. Chaos, Solitons and Fractals 2004;4:657-68

Dark matter, mirror world, and E6 unification

International Nuclear Information System (INIS)

Das, Ch. R.; Laperashvili, L. V.

2009-01-01

The idea that the ordinary (O) and mirror (M) worlds exist simultaneously is developed. It is shown that, in the case of a violated mirror parity (MP), the renormalization-group evolution of the coupling constants, which is represented in the O world by the dependence α i -1 (μ) (μ is an energy variable), is not identical to the evolution of the coupling constants α' i -1 (μ) in the M world. Here, the index i labels the symmetry group under consideration, while a dash labels quantities defined in the M world. It is assumed that E 6 unification predicted by superstring theory restores MP at the unification scale M SGUT ∼ 10 18 GeV, this inevitably leading to the difference in the violation of E 6 unification in the O and M worlds at lower energies: E 6 → SO(10) x U(1) Z and E' 6 → SU(6)' x SU(2)' Z . Considering only asymptotically free theories, we present the evolution of all the inverse coupling constants α i -1 (μ) in the one-loop approximation. In dealing with the M world involving MP violation, we then arrive at the model of the accelerating expansion of our Universe, where the axion ('acceleron') belongs to the SU(2)' Z group of the M world. The coupling constant g' Z , which grows indefinitely at the scale Λ' Z ∼ 10 -3 eV, is associated with this group. Within this theory, our Universe is in the false vacuum of the M world, in agreement with the phenomenologically observed cosmological constant of about (3 x 10 -3 eV) 4 .

String unification and leptophobic Z` in flipped SU(5)

Energy Technology Data Exchange (ETDEWEB)

Lopez, J.L. [Rice Univ., Houston, TX (United States). Bonner Nuclear Labs.

1997-01-01

We summarize recent developments in the prediction for {alpha}{sub s}(M{sub Z}), self-consistent string unification and the dynamical determination of mass scales, and leptophobic Z` gauge bosons in the context of stringy flipped SU(5). (orig.).

Aspects of supersymmetric inflation

International Nuclear Information System (INIS)

Lindblom, P.R.

1987-01-01

A new supersymmetric inflationary model is presented and shown to possess the following features: a successful slow rollover produced by quantum corrections; an acceptable pattern of supersymmetry breaking leading to the correct value of the electroweak scale; and a stable slow rollover transition to a minimum with vanishing cosmological constant. It is demonstrated that there is a class of GUT models which are compatible with an inflationary universe scenario in which: (a) the GUT and inflationary phase transitions are distinct (as in supersymmetric inflation); and (b) an observable number of GUT monopoles are created thermally due to reheating of the GUT sector after inflation. This provides one of the few ways of reconciling an observation of GUT monopoles with inflation. New techniques are developed for constructing inflationary models with multiple inflation fields, such as generalizing the one-dimensional slow rollover constraints and estimating the contribution to δρ/ρ from fluctuations transverse to the path of the slow rollover. A new method for ending the slow rollover portion of the inflationary transition is developed

Higgs boson masses in a non-minimal supersymmetric model

International Nuclear Information System (INIS)

Tiesi, Alessandro

2002-01-01

A study of the neutral Higgs spectrum in a general Z 3 -breaking Next to Minimal Supersymmetric Standard Model (NMSSM) is reported in several significant contexts. Particular attention has been devoted to the upper bound on lightest Higgs boson. In the CP-conserving case we show that the extra terms involved in the general Z 3 -breaking superpotential do not affect the upper bound which remains unchanged: it is ∼ 136 GeV when tan β = 2.7. The Spontaneous CP Violation scenario in the Z 3 -breaking NMSSM can occur at tree-level. When the phases of the fields are small the spectrum shows the lightest Higgs particle to be an almost singlet CP-odd. The second lightest particle, a doublet almost-CP-even state, still manifests the upper bound of the CP-conserving case. When the CP-violating phases are large the lightest particle is a doublet with no definite CP parity and its mass shows the usual upper bound at ∼ 136 GeV. The large number of parameters involved in the effective potential can be significantly reduced in the Infrared Quasi Fixed Point (IRQFP) resulting after solving the Renormalization Group (RG) equations assuming universality for the soft SUSY breaking masses. In the Z 3 -breaking NMSSM, unlike the Z 3 -conserving NMSSM, it is possible to find a Higgs spectrum which is still compatible with both experiment and universality at the unification scale. Because in the IRQFP regime tan β ∼ 1.8 and the stop mixing parameter is reduced then the upper bound on the lightest Higgs boson turns out to be ∼ 121 GeV. This result is compatible with experimental data coming from LEPII and might be one of the next predictions to be tested at hadron collider experiments. (author)

New grand unified models with intersecting D6-branes, neutrino masses, and flipped SU(5)

Energy Technology Data Exchange (ETDEWEB)

Cvetic, Mirjam [Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104-6396 (United States)]. E-mail: cvetic@cvetic.hep.upenn.edu; Langacker, Paul [Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104-6396 (United States); School of Natural Sciences, Institute for Advanced Study, Einstein Drive, Princeton, NJ 08540 (United States)

2007-07-30

We construct new supersymmetric SU(5) grand unified models based on Z{sub 4}xZ{sub 2} orientifolds with intersecting D6-branes. Unlike constructions based on Z{sub 2}xZ{sub 2} orientifolds, the orbifold images of the three-cycles wrapped by D6-branes correspond to new configurations and thus allow for models in which, in addition to the chiral sector in 10 and 5-bar representations of SU(5), only, there can be new sectors with (15+15-bar) and (10+10-bar) vector-pairs. We construct an example of such a globally consistent, supersymmetric model with four-families, two Standard Model Higgs pair-candidates and the gauge symmetry U(5)xU(1)xSp(4). In an N=2 sector, there are 5x(15+15-bar) and 1x(10+10-bar) vector-pairs, while another N=1 sector contains one vector-pair of 15-plets. The N=2 vector-pairs can obtain a large mass dynamically by parallel D6-brane splitting in a particular two-torus. The 15-vector-pairs provide, after symmetry breaking to the Standard Model (via parallel D-brane splitting), triplet pair candidates which can in principle play a role in generating Majorana-type masses for left-handed neutrinos, though the necessary Yukawa couplings are absent in the specific construction. This model can also be interpreted as a flipped SU(5)xU(1){sub X} grand unified model where the 10-vector-pairs can play the role of Higgs fields, though again there are phenomenological difficulties for the specific construction.

SU(5)×U(1)X grand unification with minimal seesaw and Z‧-portal dark matter

Science.gov (United States)

Okada, Nobuchika; Okada, Satomi; Raut, Digesh

2018-05-01

We propose a grand unified SU (5) × U(1)X model, where the standard SU(5) grand unified theory is supplemented by minimal seesaw and a right-handed neutrino dark matter with an introduction of a global Z2-parity. In the presence of three right-handed neutrinos (RHNs), the model is free from all gauge and mixed-gravitational anomalies. The SU(5) symmetry is broken into the Standard Model (SM) gauge group at MGUT ≃ 4 ×1016GeV in the standard manner, while the U(1)X symmetry breaking occurs at the TeV scale, which generates the TeV-scale mass of the U(1)X gauge boson (Z‧ boson) and the three Majorana RHNs. A unique Z2-odd RHN is stable and serves as the dark matter (DM) in the present Universe, while the remaining two RHNs work to generate the SM neutrino masses through the minimal seesaw. We investigate the Z‧-portal RHN DM scenario in this model context. We find that the constraints from the DM relic abundance, and the Z‧ boson search at the Large Hadron Collider (LHC), and the perturbativity bound on the U(1)X gauge coupling are complementary to narrow down the allowed parameter region in the range of 3.0 ≤mZ‧ [TeV ] ≤ 9.2 for the Z‧ boson mass. The allowed region for mZ‧ ≤ 5TeV will be fully covered by the future LHC experiments. We also briefly discuss the successful implementation of Baryogenesis and cosmological inflation scenarios in the present model.

Les représentations de la réunification allemande dans l’ex-Yougoslavie

Directory of Open Access Journals (Sweden)

Laurent Hassid

2012-06-01

Full Text Available La réunification allemande a été perçue de manière différente dans les États de l’ex-Yougoslavie. En Serbie, république la plus peuplée de la Fédération et où se trouve le pouvoir central, elle est crainte comme le symbole d’une possible désintégration. En Croatie et en Slovénie s’est ainsi répandue l’idée que « si l’Allemagne peut se réunifier, la Yougoslavie peut bien se désintégrer » (Entretien avec Vladimir Radomirovic, ancien rédacteur en chef du quotidien serbe Politika et fondateur en 2009 de Pistaljka, site Internet qui dénonce la corruption dans les Balkans - www.pistaljka.rs. Au risque de provoquer une crise au sein de la CEE, l’Allemagne a poussé les autres grandes puissances du continent, dont la France, à reconnaître rapidement les indépendances des deux républiques. Pour comprendre les différentes représentations de la réunification allemande dans les Balkans, il est nécessaire d’étudier également les perceptions de la chute du Mur de Berlin, un an plus tôt. Symbole d’un communisme qui n’est pas tombé partout dans l’ex-Yougoslavie à partir de 1991, il a néanmoins grandement participé à la désintégration de la Fédération. Vingt ans après, l’Allemagne reste un acteur majeur dans la région, mais a abandonné une partie de son influence économique et politique au profit de l’Union européenne, notamment à partir de l’introduction de l’euro qui prend la place du mark, ancienne devise de référence.

The supersymmetric Adler-Bardeen theorem and regularization by dimensional reduction

International Nuclear Information System (INIS)

Ensign, P.; Mahanthappa, K.T.

1987-01-01

We examine the subtraction scheme dependence of the anomaly of the supersymmetric, gauge singlet axial current in pure and coupled supersymmetric Yang-Mills theories. Preserving supersymmetry and gauge invariance explicitly by using supersymmetric background field theory and dimensional reduction, we show that only the one-loop value of the axial anomaly is subtraction scheme independent, and that one can always define a subtraction scheme in which the Adler-Bardeen theorem is satisfied to all orders in perturbation theory. In general this subtraction scheme may be non-minimal, but in both the pure and the coupled theories, the Adler-Bardeen theorem is satisfied to two loops in minimal subtraction. (orig.)

Induced gravity II: grand unification

Energy Technology Data Exchange (ETDEWEB)

Einhorn, Martin B. [Kavli Institute for Theoretical Physics, Kohn Hall,University of California,Santa Barbara, CA 93106-4030 (United States); Jones, D.R. Timothy [Kavli Institute for Theoretical Physics, Kohn Hall,University of California,Santa Barbara, CA 93106-4030 (United States); Dept. of Mathematical Sciences, University of Liverpool,Peach Street, Liverpool L69 3BX (United Kingdom)

2016-05-31

As an illustration of a renormalizable, asymptotically-free model of induced gravity, we consider an SO(10) gauge theory interacting with a real scalar multiplet in the adjoint representation. We show that dimensional transmutation can occur, spontaneously breaking SO(10) to SU(5)⊗U(1), while inducing the Planck mass and a positive cosmological constant, all proportional to the same scale v. All mass ratios are functions of the values of coupling constants at that scale. Below this scale (at which the Big Bang may occur), the model takes the usual form of Einstein-Hilbert gravity in de Sitter space plus calculable corrections. We show that there exist regions of parameter space in which the breaking results in a local minimum of the effective action giving a positive dilaton (mass){sup 2} from two-loop corrections associated with the conformal anomaly. Furthermore, unlike the singlet case we considered previously, some minima lie within the basin of attraction of the ultraviolet fixed point. Moreover, the asymptotic behavior of the coupling constants also lie within the range of convergence of the Euclidean path integral, so there is hope that there will be candidates for sensible vacua. Although open questions remain concerning unitarity of all such renormalizable models of gravity, it is not obvious that, in curved backgrounds such as those considered here, unitarity is violated. In any case, any violation that may remain will be suppressed by inverse powers of the reduced Planck mass.

Two-dimensional nonlinear equations of supersymmetric gauge theories

International Nuclear Information System (INIS)

Savel'ev, M.V.

1985-01-01

Supersymmetric generalization of two-dimensional nonlinear dynamical equations of gauge theories is presented. The nontrivial dynamics of a physical system in the supersymmetry and supergravity theories for (2+2)-dimensions is described by the integrable embeddings of Vsub(2/2) superspace into the flat enveloping superspace Rsub(N/M), supplied with the structure of a Lie superalgebra. An equation is derived which describes a supersymmetric generalization of the two-dimensional Toda lattice. It contains both super-Liouville and Sinh-Gordon equations

Solving the Little Hierarchy Problem with a Singlet and Explicit μ Terms

International Nuclear Information System (INIS)

Delgado, Antonio; Kolda, Christopher; Olson, J. Pocahontas; Puente, Alejandro de la

2010-01-01

We present a generalization of the next-to-minimal supersymmetric standard model, with an explicit μ term and a supersymmetric mass for the singlet superfield, as a route to alleviating the little hierarchy problem of the minimal supersymmetric standard model (MSSM). Though this model does not address the μ problem of the MSSM, we are able to generate masses for the lightest neutral Higgs boson up to 140 GeV with top squarks below the TeV scale, all couplings perturbative to the gauge unification scale, and with no need to fine-tune parameters in the scalar potential. This model more closely resembles the MSSM phenomenologically than the canonical next-to-minimal supersymmetric standard model.

Search for supersymmetric particles at CDF

International Nuclear Information System (INIS)

Wagner, R.G.

1989-01-01

Analyses of events with large unbalanced transverse energy from the 1987 and 1988-89 CDF data runs have set limits on the masses of supersymmetric squarks and gluinos. In a simple model with a stable photino as the lightest supersymmetric particle, the 1987 data with an integrated luminosity of 25.3 nb -1 have excluded at the 90% CL, squarks of mass less than 73 GeV/c 2 and gluinos of mass less than 74 GeV/c 2 . Preliminary results from an analysis of 1 pb -1 of data from the current 1988-89 run imply that the existence of a squark of mass less than 150 GeV/c 2 is unlikely. 4 refs., 2 fig., 1 tab

Exploring the Use of Enterprise Content Management Systems in Unification Types of Organizations

Directory of Open Access Journals (Sweden)

Arshad Noreen Izza

2014-03-01

Full Text Available The aim of this paper is to better understand how highly standardized and integrated businesses known as unification types of organizations use Enterprise Content Management Systems (ECMS to support their business processes. Multiple case study approach was used to study the ways two unification organizations use their ECMS in their daily work practices. Arising from these case studies are insights into the differing ways in which ECMS is used to support businesses. Based on the comparisons of the two cases, this study proposed that unification organizations may use ECMS in four ways, for: (1 collaboration, (2 information sharing that supports a standardized process structure, (3 building custom workflows that support integrated and standardized processes, and (4 providing links and access to information systems. These findings may guide organizations that are highly standardized and integrated in fashion, to achieve their intended ECMS-use, to understand reasons for ECMS failures and underutilization and to exploit technologies investments.

Supersymmetry, the flavour puzzle and rare B decays

International Nuclear Information System (INIS)

Straub, David Michael

2010-01-01

The gauge hierarchy problem and the flavour puzzle belong to the most pressing open questions in the Standard Model of particle physics. Supersymmetry is arguably the most popular framework of physics beyond the Standard Model and provides an elegant solution to the gauge hierarchy problem; however, it aggravates the flavour puzzle. In the first part of this thesis, I discuss several approaches to address the flavour puzzle in the minimal supersymmetric extension of the Standard Model and experimental tests thereof: supersymmetric grand unified theories with a unification of Yukawa couplings at high energies, theories with minimal flavour violation and additional sources of CP violation and theories with gauge mediation of supersymmetry breaking and a large ratio of Higgs vacuum expectation values. In the second part of the thesis, I discuss the phenomenology of two rare B meson decay modes which are promising probes of physics beyond the Standard Model: The exclusive B → K * l + l - decay, whose angular decay distribution will be studied at LHC and gives access to a large number of observables and the b→sνanti ν decays, which are in the focus of planned high-luminosity Super B factories. I discuss the predictions for these observables in the Standard Model and their sensitivity to New Physics. (orig.)

Discrete symmetries in the MSSM

Energy Technology Data Exchange (ETDEWEB)

Schieren, Roland

2010-12-02

The use of discrete symmetries, especially abelian ones, in physics beyond the standard model of particle physics is discussed. A method is developed how a general, abelian, discrete symmetry can be obtained via spontaneous symmetry breaking. In addition, anomalies are treated in the path integral approach with special attention to anomaly cancellation via the Green-Schwarz mechanism. All this is applied to the minimal supersymmetric standard model. A unique Z{sup R}{sub 4} symmetry is discovered which solves the {mu}-problem as well as problems with proton decay and allows to embed the standard model gauge group into a simple group, i.e. the Z{sup R}{sub 4} is compatible with grand unification. Also the flavor problem in the context of minimal flavor violation is addressed. Finally, a string theory model is presented which exhibits the mentioned Z{sup R}{sub 4} symmetry and other desirable features. (orig.)

Discrete symmetries in the MSSM

International Nuclear Information System (INIS)

Schieren, Roland

2010-01-01

The use of discrete symmetries, especially abelian ones, in physics beyond the standard model of particle physics is discussed. A method is developed how a general, abelian, discrete symmetry can be obtained via spontaneous symmetry breaking. In addition, anomalies are treated in the path integral approach with special attention to anomaly cancellation via the Green-Schwarz mechanism. All this is applied to the minimal supersymmetric standard model. A unique Z R 4 symmetry is discovered which solves the μ-problem as well as problems with proton decay and allows to embed the standard model gauge group into a simple group, i.e. the Z R 4 is compatible with grand unification. Also the flavor problem in the context of minimal flavor violation is addressed. Finally, a string theory model is presented which exhibits the mentioned Z R 4 symmetry and other desirable features. (orig.)

Supersymmetric models for quarks and leptons with nonlinearly realized E8 symmetry

International Nuclear Information System (INIS)

Ong, C.L.

1985-01-01

We propose three supersymmetric nonlinear sigma models with global symmetry E 8 . The models can accommodate three left-handed families of quarks and leptons without incurring the Adler-Bell-Jackiw anomaly with respect to either the standard SU(3) x SU(2) x U(1) gauge group, or the SU(5), or SO(10) grand unifying gauge group. They also predict unambiguously a right-handed, fourth family of quarks and leptons. In order to explore the structure of the models, we develop a differential-form formulation of the Kahler manifolds, resulting in general expressions for the curvature tensors and other geometrical objects in terms of the structure constants of the algebra, and the squashing parameters. These results, in turn, facilitate a general method for determining the Lagrangian to quartic order, and so the structure of the inherent four-fermion interactions of the models. We observe that the Kahlerian condition dω = 0 on the fundamental two-form ω greatly reduces the number of the independent squashing parameters. We also point out two plausible mechanisms for symmetry breaking, involving gravity

Nonlinear realization of supersymmetric AdS space isometries

International Nuclear Information System (INIS)

Clark, T. E.; Love, S. T.

2006-01-01

The isometries of AdS 5 space and supersymmetric AdS 5 xS 1 space are nonlinearly realized on four-dimensional Minkowski space. The resultant effective actions in terms of the Nambu-Goldstone modes are constructed. The dilatonic mode governing the motion of the Minkowski space probe brane into the covolume of supersymmetric AdS 5 space is found to be unstable and the bulk of the AdS 5 space is unable to sustain the brane. No such instability appears in the nonsupersymmetric case

Low energy dynamics of monopoles in supersymmetric Yang-Mills theories with hypermultiplets

International Nuclear Information System (INIS)

Kim, Chanju

2006-01-01

We derive the low energy dynamics of monopoles and dyons in N = 2 supersymmetric Yang-Mills theories with hypermultiplets in arbitrary representations by utilizing a collective coordinate expansion. We consider the most general case that Higgs fields both in the vector multiplet and in the hypermultiplets have nonzero vacuum expectation values. The resulting theory is a supersymmetric quantum mechanics which has been obtained by a nontrivial dimensional reduction of two-dimensional (4,0) supersymmetric sigma models with potentials

Supersymmetric KP hierarchy in N=1 superspace and its N=2 reductions

International Nuclear Information System (INIS)

Lechtenfeld, O.; Sorin, A.

2000-01-01

A wide class of N=2 reductions of the supersymmetric KP hierarchy in N=1 superspace is described. This class includes a new N=2 supersymmetric generalization of the Toda chain hierarchy. The Lax pair representations of the bosonic and fermionic flows, local and non-local Hamiltonians, finite and infinite discrete symmetries, first two Hamiltonian structures and the recursion operator of this hierarchy are constructed. Its secondary reduction to new N=2 supersymmetric modified KdV hierarchy is discussed

Supersymmetric KP hierarchy in N=1 superspace and its N=2 reductions

International Nuclear Information System (INIS)

Lechtenfeld, O.; Sorin, A.

1999-01-01

A wide class of N=2 reductions of the supersymmetric KP hierarchy in N=1 superspace is described. This class includes a new N=2 supersymmetric generalization of the Toda chain hierarchy. The Lax pair representations of the bosonic and fermionic flows, local and nonlocal Hamiltonians, finite and infinite discrete symmetries, first two Hamiltonian structures and the recursion operator of this hierarchy are constructed. Its secondary reduction to new N=2 supersymmetric modified KdV hierarchy is discussed

Continuous degeneracy of non-supersymmetric vacua

International Nuclear Information System (INIS)

Sun Zheng

2009-01-01

In global supersymmetric Wess-Zumino models with minimal Kaehler potentials, F-type supersymmetry breaking always yields instability or continuous degeneracy of non-supersymmetric vacua. As a generalization of the original O'Raifeartaigh's result, the existence of instability or degeneracy is true to any higher order corrections at tree level for models even with non-renormalizable superpotentials. The degeneracy generically coincides the R-axion direction under some assumptions of R-charge assignment, but generally requires neither R-symmetries nor any assumption of generic superpotentials. The result also confirms the well-known fact that tree level supersymmetry breaking is a very rare occurrence in global supersymmetric theories with minimal Kaehler potentials. The implication for effective field theory method in the landscape is discussed and we point out that choosing models with minimal Kaehler potentials may result in unexpected answers to the vacuum statistics. Supergravity theories or theories with non-minimal Kaehler potentials in general do not suffer from the existence of instability or degeneracy. But very strong gauge dynamics or small compactification dimension reduces the Kaehler potential from non-minimal to minimal, and gravity decoupling limit reduces supergravity to global supersymmetry. Instability or degeneracy may appear in these limits. Away from these limits, a large number of non-SUSY vacua may still be found in an intermediate region.

Proton and neutron decay rates in conventional and supersymmetric guts

International Nuclear Information System (INIS)

Salati, P.; Wallet, J.C.

1982-01-01

We present a general calculation of the two body decay rates of the nucleon, for the most general form of four-fermion ΔB = ΔL operators, in the framework of the SU(6) non-relativistic quark model. We have applied our general formulas to Higgs mediated decays in conventional and in supersymmetric SU(5) models. Lower bounds upon, the exchanged particles masses are given. We point out that the hierarchies of branching ratios in decays mediated by Higgs bosons are different from those of gauge boson decay modes (in the former case, neutrinos modes are dominant). We give, in conclusion, an experimental way to distinguish non-supersymmetric GUTs from supersymmetric ones, if the nucleon decays via Higgs bosons

Supersymmetric Gödel Universes in string theory

DEFF Research Database (Denmark)

Harmark, Troels; Takayanagi, Tadashi

2003-01-01

Supersymmetric backgrounds in string and M-theory of the Gödel Universe type are studied. We find several new Gödel Universes that preserve up to 20 supersymmetries. In particular, we obtain an interesting Gödel Universe in M-theory with 18 supersymmetries which does not seem to be dual to a pp......-wave. We show that not only T-duality but also the type-IIA/M-theory S-duality can give supersymmetric Gödel Universes from pp-waves. We find solutions that can interpolate between Gödel Universes and pp-waves. We also compute the string spectrum on two type IIA Gödel Universes. Furthermore, we obtain...

Low energy gauge couplings in grand unified theories and high precision physics

International Nuclear Information System (INIS)

Lynn, B.W.

1993-09-01

I generalize the leading log relations between low energy SU(3) QCD , SU(2) rvec I and U(l) Y effective gauge couplings to include all one-loop threshold effects of matter fields in oblique vector self energy quantum corrections for both supersymmetric and non-supersymmetric SU(5) grand unified theories. These always involve an exactly conserved current from the unbroken SU(3) QCD x U(L) QED subgroup; this fact strongly constrains any non-decoupling of heavy states as well as the generic character of threshold effects. Relations between low energy gauge couplings depend on the details of the spectra of both the superheavy and low mass sectors; I display the common origin of the logs appropriate to superheavy matter states, which can be found with well known renormalization group techniques, and the combination of logs and polynomials appropriate for light matter states, which cannot. Relations between any two or all three low energy effective gauge couplings do not depend on the top quark or standard model Higgs' masses. Neither do they depend on neutral color singlet states such as other neutral color singlet Higgs' or higgsinos, neutrinos, zinos or photinos. Further, they do not depend on degenerate SU(5) matter representations, of either spin 0 or spin 1/2 of any mass; matter representations of SU(5) can affect such relations only if there is mass splitting within them. The b quark splitting from the τ and ν τ can affect the relation between gauge couplings for |q 2 | → m b 2 as can hadronic resonances and multi-hadron states for lower |q 2 |. New mass-split representations of light states, such as occur in supersymmetric theories, can also affect such relations

Low energy gauge couplings in grand unified theories and high precision physics

Energy Technology Data Exchange (ETDEWEB)

Lynn, B.W. [Stanford Univ., CA (United States). Dept. of Physics]|[Superconducting Super Collider Lab., Dallas, TX (United States)

1993-09-01

I generalize the leading log relations between low energy SU(3){sub QCD}, SU(2){sub {rvec I}} and U(l){sub Y} effective gauge couplings to include all one-loop threshold effects of matter fields in oblique vector self energy quantum corrections for both supersymmetric and non-supersymmetric SU(5) grand unified theories. These always involve an exactly conserved current from the unbroken SU(3){sub QCD} {times} U(L){sub QED} subgroup; this fact strongly constrains any non-decoupling of heavy states as well as the generic character of threshold effects. Relations between low energy gauge couplings depend on the details of the spectra of both the superheavy and low mass sectors; I display the common origin of the logs appropriate to superheavy matter states, which can be found with well known renormalization group techniques, and the combination of logs and polynomials appropriate for light matter states, which cannot. Relations between any two or all three low energy effective gauge couplings do not depend on the top quark or standard model Higgs` masses. Neither do they depend on neutral color singlet states such as other neutral color singlet Higgs` or higgsinos, neutrinos, zinos or photinos. Further, they do not depend on degenerate SU(5) matter representations, of either spin 0 or spin 1/2 of any mass; matter representations of SU(5) can affect such relations only if there is mass splitting within them. The b quark splitting from the {tau} and {nu}{sub {tau}} can affect the relation between gauge couplings for {vert_bar}q{sub 2}{vert_bar} {yields} m{sub b}{sup 2} as can hadronic resonances and multi-hadron states for lower {vert_bar}q{sub 2}{vert_bar}. New mass-split representations of light states, such as occur in supersymmetric theories, can also affect such relations.

Planarizable Supersymmetric Quantum Toboggans

Czech Academy of Sciences Publication Activity Database

Znojil, Miloslav

2011-01-01

Roč. 7, - (2011), 018/1-018/23 ISSN 1815-0659. [Workshop on Supersymmetric Quantum Mechanics and Spectral Design. Benasque, 18.07.2010-30.07. 2010] R&D Projects: GA ČR GAP203/11/1433 Institutional research plan: CEZ:AV0Z10480505 Keywords : supersymmetry * Schrodinger equation * complexified coordinates Subject RIV: BE - Theoretical Physics Impact factor: 1.071, year: 2011

Supersymmetric Recipes (1/3)

CERN Multimedia

CERN. Geneva

2011-01-01

In these lectures, I shall describe the theory of supersymmetry accessible to people with a knowledge of basic quantum field theory. The lectures will contain recipes of how to calculate which interactions (and which special relations) are in supersymmetry, without providing detailed proofs of where they come from. We shall also cover: motivation for weak-scale supersymmetry and the minimal supersymmetric standard model.

Einstein's Last Dream: The Space–Time Unification of Fundamental ...

Indian Academy of Sciences (India)

Home; Journals; Resonance – Journal of Science Education; Volume 3; Issue 1. Einstein's Last Dream: The Space – Time Unification of Fundamental Forces. Abdus Salam. Reflections Volume 3 Issue 1 January 1998 pp 81-88. Fulltext. Click here to view fulltext PDF. Permanent link:

Educational Systems and Rising Inequality: Eastern Germany after Unification

Science.gov (United States)

von Below, Susanne; Powell, Justin J. W.; Roberts, Lance W.

2013-01-01

Educational systems considerably influence educational opportunities and the resulting social inequalities. Contrasting institutional regulations of both structures and contents, the authors present a typology of educational system types in Germany to analyze their effects on social inequality in eastern Germany after unification. After 1990, the…

Deviations from Newton's law in supersymmetric large extra dimensions

International Nuclear Information System (INIS)

Callin, P.; Burgess, C.P.

2006-01-01

Deviations from Newton's inverse-squared law at the micron length scale are smoking-gun signals for models containing supersymmetric large extra dimensions (SLEDs), which have been proposed as approaches for resolving the cosmological constant problem. Just like their non-supersymmetric counterparts, SLED models predict gravity to deviate from the inverse-square law because of the advent of new dimensions at sub-millimeter scales. However SLED models differ from their non-supersymmetric counterparts in three important ways: (i) the size of the extra dimensions is fixed by the observed value of the dark energy density, making it impossible to shorten the range over which new deviations from Newton's law must be seen; (ii) supersymmetry predicts there to be more fields in the extra dimensions than just gravity, implying different types of couplings to matter and the possibility of repulsive as well as attractive interactions; and (iii) the same mechanism which is purported to keep the cosmological constant naturally small also keeps the extra-dimensional moduli effectively massless, leading to deviations from general relativity in the far infrared of the scalar-tensor form. We here explore the deviations from Newton's law which are predicted over micron distances, and show the ways in which they differ and resemble those in the non-supersymmetric case

Supersymmetric classical mechanics: free case

Energy Technology Data Exchange (ETDEWEB)

Rodrigues, R. de Lima [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)]|[Paraiba Univ., Cajazeiras, PB (Brazil). Dept. de Ciencias Exatas e da Natureza]. E-mail: rafael@cfp.ufpb.br; Almeida, W. Pires de [Paraiba Univ., Cajazeiras, PB (Brazil). Dept. de Ciencias Exatas e da Natureza; Fonseca Neto, I. [Paraiba Univ., Campina Grande, PB (Brazil). Dept. de Fisica

2001-06-01

We present a review work on Supersymmetric Classical Mechanics in the context of a Lagrangian formalism, with N = 1-supersymmetry. We show that the N = 1 supersymmetry does not allow the introduction of a potencial energy term depending on a single commuting supercoordinate, {phi}(t;{theta}). (author)

Two-loop anomalous dimensions for four-Fermi operators in supersymmetric theories

Directory of Open Access Journals (Sweden)

Junji Hisano

2017-09-01

Full Text Available We derive two-loop anomalous dimensions for four-Fermi operators in supersymmetric theories using the effective Kähler potential. We introduce the general forms in generic gauge theories and apply our results to the flavor-changing operators in (minimal supersymmetric standard models.

N=12 supersymmetric four-dimensional nonlinear σ-models from nonanticommutative superspace

International Nuclear Information System (INIS)

Hatanaka, Tomoya; Ketov, Sergei V.; Kobayashi, Yoshishige; Sasaki, Shin

2005-01-01

The component structure of a generic N=1/2 supersymmetric nonlinear sigma-model (NLSM) defined in the four-dimensional (Euclidean) nonanticommutative (NAC) superspace is investigated in detail. The most general NLSM is described in terms of arbitrary Kahler potential, and chiral and antichiral superpotentials. The case of a single chiral superfield gives rise to splitting of the NLSM potentials, whereas the case of several chiral superfields results in smearing (or fuzziness) of the NLSM potentials, while both effects are controlled by the auxiliary fields. We eliminate the auxiliary fields by solving their algebraic equations of motion, and demonstrate that the results are dependent upon whether the auxiliary integrations responsible for the fuzziness are performed before or after elimination of the auxiliary fields. There is no ambiguity in the case of splitting, i.e., for a single chiral superfield. Fully explicit results are derived in the case of the N=1/2 supersymmetric NAC-deformed CP n NLSM in four dimensions. Here we find another surprise that our results differ from the N=1/2 supersymmetric CP n NLSM derived by the quotient construction from the N=1/2 supersymmetric NAC-deformed gauge theory. We conclude that an N=1/2 supersymmetric deformation of a generic NLSM from the NAC superspace is not unique

Supersymmetric quantum mechanics and new potentials

International Nuclear Information System (INIS)

Drigo Filho, E.

1988-01-01

Using the supersymmetric quantum mechanics the following potential are generalized. The particle in the box, Poeschl-Teller and Rosen-Morse. The new potentials are evaluated and their eigenfunctions and spectra are indicated. (author) [pt

Introduction to unification of electromagnetic and weak interactions

International Nuclear Information System (INIS)

Martin, F.

1980-01-01

After reviewing the present status of weak interaction phenomenology we discuss the basic principles of gauge theories. Then we show how Higgs mechanism can give massive quanta of interaction. The so-called 'Weinberg-Salam' model, which unifies electromagnetic and weak interactions, is described. We conclude with a few words on unification with strong interactions and gravity [fr

A4 family symmetry and quark-lepton unification

International Nuclear Information System (INIS)

King, Stephen F.; Malinsky, Michal

2007-01-01

We present a model of quark and lepton masses and mixings based on A 4 family symmetry, a discrete subgroup of an SO(3) flavour symmetry, together with Pati-Salam unification. It accommodates tri-bimaximal neutrino mixing via constrained sequential dominance with a particularly simple vacuum alignment mechanism emerging through the effective D-term contributions to the scalar potential

Standard coupling unification in SO(10), hybrid seesaw neutrino mass and leptogenesis, dark matter, and proton lifetime predictions

Energy Technology Data Exchange (ETDEWEB)

Parida, M.K.; Nayak, Bidyut Prava; Satpathy, Rajesh [Centre of Excellence in Theoretical and Mathematical Sciences,Siksha ‘O’ Anusandhan University,Khandagiri Square, Bhubaneswar 751030 (India); Awasthi, Ram Lal [Indian Institute of Science Education and Research,Knowledge City, Sector 81, SAS Nagar, Manauli 140306 (India)

2017-04-12

We discuss gauge coupling unification of SU(3){sub C}×SU(2){sub L}×U(1){sub Y} descending directly from non-supersymmetric SO(10) while providing solutions to the three outstanding problems of the standard model: neutrino masses, dark matter, and the baryon asymmetry of the universe. Conservation of matter parity as gauged discrete symmetry for the stability and identification of dark matter in the model calls for high-scale spontaneous symmetry breaking through 126{sub H} Higgs representation. This naturally leads to the hybrid seesaw formula for neutrino masses mediated by heavy scalar triplet and right-handed neutrinos. Being quadratic in the Majorana coupling, the seesaw formula predicts two distinct patterns of right-handed neutrino masses, one hierarchical and another not so hierarchical (or compact), when fitted with the neutrino oscillation data. Predictions of the baryon asymmetry via leptogenesis are investigated through the decays of both the patterns of RHν masses. A complete flavor analysis has been carried out to compute CP-asymmetries including washouts and solutions to Boltzmann equations have been utilised to predict the baryon asymmetry. The additional contribution to vertex correction mediated by the heavy left-handed triplet scalar is noted to contribute as dominantly as other Feynman diagrams. We have found successful predictions of the baryon asymmetry for both the patterns of right-handed neutrino masses. The SU(2){sub L} triplet fermionic dark matter at the TeV scale carrying even matter parity is naturally embedded into the non-standard fermionic representation 45{sub F} of SO(10). In addition to the triplet scalar and the triplet fermion, the model needs a nonstandard color octet fermion of mass ∼5×10{sup 7} GeV to achieve precision gauge coupling unification at the GUT mass scale M{sub U}{sup 0}=10{sup 15.56} GeV. Threshold corrections due to superheavy components of 126{sub H} and other representations are estimated and found to be

Exactness of supersymmetric WKB method for translational shape invariant potentials

International Nuclear Information System (INIS)

Cheng, K M; Leung, P T; Pang, C S

2003-01-01

By examining the generic form of the superpotential of translational shape invariant potentials (TSIPs), we explicitly show the exactness of the lowest order supersymmetric WKB (SWKB) formula for TSIPs. Remarkably, our method applies to both unbroken and broken supersymmetric systems. We also demonstrate the equivalence of one-parameter and multi-parameter TSIPs, thus establishing the exactness of the SWKB formula for all TSIPs

Exactness of supersymmetric WKB method for translational shape invariant potentials

CERN Document Server

Cheng, K M; Pang, C S

2003-01-01

By examining the generic form of the superpotential of translational shape invariant potentials (TSIPs), we explicitly show the exactness of the lowest order supersymmetric WKB (SWKB) formula for TSIPs. Remarkably, our method applies to both unbroken and broken supersymmetric systems. We also demonstrate the equivalence of one-parameter and multi-parameter TSIPs, thus establishing the exactness of the SWKB formula for all TSIPs.

Supersymmetrically transformed periodic potentials

OpenAIRE

C, David J. Fernandez

2003-01-01

The higher order supersymmetric partners of a stationary periodic potential are studied. The transformation functions associated to the band edges do not change the spectral structure. However, when the transformation is implemented for factorization energies inside of the forbidden bands, the final potential will have again the initial band structure but it can have bound states encrusted into the gaps, giving place to localized periodicity defects.

Susy and Such

International Nuclear Information System (INIS)

Dawson, S.

1997-01-01

In these lectures, the author discusses the theoretical motivation for supersymmetric theories and introduce the minimal low energy effective supersymmetric theory, (MSSM). I consider only the MSSM and its simplest grand unified extension here. Some of the other possible low-energy SUSY models are summarized. The particles and their interactions are examined in detail in the next sections and a grand unified SUSY model presented which gives additional motivation for pursuing supersymmetric theories

Supersymmetric U(1)' model with multiple dark matters

International Nuclear Information System (INIS)

Hur, Taeil; Lee, Hye-Sung; Nasri, Salah

2008-01-01

We consider a scenario where a supersymmetric model has multiple dark matter particles. Adding a U(1) ' gauge symmetry is a well-motivated extension of the minimal supersymmetric standard model (MSSM). It can cure the problems of the MSSM such as the μ problem or the proton decay problem with high-dimensional lepton number and baryon number violating operators which R parity allows. An extra parity (U parity) may arise as a residual discrete symmetry after U(1) ' gauge symmetry is spontaneously broken. The lightest U-parity particle (LUP) is stable under the new parity becoming a new dark matter candidate. Up to three massive particles can be stable in the presence of the R parity and the U parity. We numerically illustrate that multiple stable particles in our model can satisfy both constraints from the relic density and the direct detection, thus providing a specific scenario where a supersymmetric model has well-motivated multiple dark matters consistent with experimental constraints. The scenario provides new possibilities in the present and upcoming dark matter searches in the direct detection and collider experiments

The string unification of gauge couplings and gauge kinetic mixings

International Nuclear Information System (INIS)

Hattori, Chuichiro; Matsuda, Masahisa; Matsuoka, Takeo; Mochinaga, Daizo.

1993-01-01

In the superstring models we have not only the complete 27 multiplets of E 6 but also extra incomplete (27+27-bar) chiral supermultiplets being alive at low energies. Associated with these additional multiplets, when the gauge symmetry contains more than one U(1) gauge group, there may exist gauge kinetic mixings among these U(1) gauge groups. In such cases the effect of gauge kinetic mixings should be incorporated into the study of unification of gauge couplings. We study these interesting effects systematically in these models. The string threshold effect is also taken into account. It is found that in the four-generation models we do not have an advisable solution of string unification of gauge couplings consistent with experimental values at the electroweak scale. We also discuss the possible scenarios to solve this problem. (author)

Localization of supersymmetric field theories on non-compact hyperbolic three-manifolds

Energy Technology Data Exchange (ETDEWEB)

Assel, Benjamin; Martelli, Dario; Murthy, Sameer; Yokoyama, Daisuke [Department of Mathematics, King’s College London,The Strand, London WC2R 2LS (United Kingdom)

2017-03-17

We study supersymmetric gauge theories with an R-symmetry, defined on non-compact, hyperbolic, Riemannian three-manifolds, focusing on the case of a supersymmetry-preserving quotient of Euclidean AdS{sub 3}. We compute the exact partition function in these theories, using the method of localization, thus reducing the problem to the computation of one-loop determinants around a supersymmetric locus. We evaluate the one-loop determinants employing three different techniques: an index theorem, the method of pairing of eigenvalues, and the heat kernel method. Along the way, we discuss aspects of supersymmetry in manifolds with a conformal boundary, including supersymmetric actions and boundary conditions.

Family unification within SO(15)

International Nuclear Information System (INIS)

Enqvist, K.; Maalampi, J.

1981-01-01

We present a model for the unification of fermion families based on the gauge symmetry SO(15). It is a minimal SO(n) model which can accommodate the known fermions within a single irreducible representation. The model predicts four ordinary fermion families and four families of mirror fermions. The latter have V + A weak interactions, and their mass scale is predicted to be 10 2 GeV/c 2 . We argue that radiative corrections to the fermion masses can cause non-negligible mixing between ordinary and mirror fermions. The implications of these mixings for the weak interaction phenomenology and solar neutrinos are discussed. (orig.)

Dispersive and damping properties of supersymmetric sound. 1

International Nuclear Information System (INIS)

Lebedev, V.V.; Smilga, A.V.

1988-01-01

It is shown that a supersymmetric medium at nonzero temperature possesses necessarily the massless fermionic collective excitation which we call phonino. Its appearance is due to the spontaneous SUSY breaking at T ≠ and is as general as the appearance of the sound. The phase velocity of phonino is C=P/E where P is the pressure and E is the energy density of the medium. The Wess-Zumino model is studied in detail. In the case of small temperature, T 2 , where g<<1 is the coupling constant, and small. The gauge supersymmetric theories are also discussed

Supersymmetric hybrid inflation with non-minimal Kahler potential

International Nuclear Information System (INIS)

Bastero-Gil, M.; King, S.F.; Shafi, Q.

2007-01-01

Minimal supersymmetric hybrid inflation based on a minimal Kahler potential predicts a spectral index n s ∼>0.98. On the other hand, WMAP three year data prefers a central value n s ∼0.95. We propose a class of supersymmetric hybrid inflation models based on the same minimal superpotential but with a non-minimal Kahler potential. Including radiative corrections using the one-loop effective potential, we show that the prediction for the spectral index is sensitive to the small non-minimal corrections, and can lead to a significantly red-tilted spectrum, in agreement with WMAP

Thermal leptogenesis in a supersymmetric neutrinophilic Higgs model

International Nuclear Information System (INIS)

Haba, Naoyuki; Seto, Osamu

2011-01-01

We investigate thermal leptogenesis in a supersymmetric neutrinophilic Higgs model by taking phenomenological constraints into account, where, in addition to the minimal supersymmetric standard model, we introduce an extra Higgs field with a tiny vacuum expectation value which generates neutrino masses. Thanks to this tiny vacuum expectation value of the neutrinophilic Higgs, our model allows us to reduce the mass of the lightest right-handed (s)neutrino to be O(10 5 ) GeV, keeping sufficiently large CP asymmetry in its decay. Therefore, the reheating temperature after inflation is not necessarily high; hence this scenario is free from the gravitino problem.

Second Hopf map and supersymmetric mechanics with Yang monopole

International Nuclear Information System (INIS)

Gonzales, M.; Toppan, F.; Kuznetsova, Z.; Nersessian, F.; Yeghikyan, V.

2009-01-01

We propose to use the second Hopf map for the reduction (via SU(2) group action) of the eight-dimensional supersymmetric mechanics to five-dimensional supersymmetric systems specified by the presence of an SU(2) Yang monopole. For our purpose we develop the relevant Lagrangian reduction procedure. The reduced system is characterized by its invariance under the N = 5 or N = 4 supersymmetry generators (with or without an additional conserved BRST charge operator) which commute with the su(2) generators. (author)

Supersymmetric contributions to the decay of an extra Z boson

International Nuclear Information System (INIS)

Gherghetta, T.; Kaeding, T.A.; Kane, G.L.

1998-01-01

We analyze in detail the supersymmetric contributions to the decay of an extra Z boson in effective rank 5 models, including the important effect of D terms on sfermion masses. The inclusion of supersymmetric decay channels will reduce the Z ' branching ratio to standard model particles, resulting in lower Z ' mass limits than those often quoted. In particular, the supersymmetric parameter space motivated by the recent Fermilab eeγγ event and other suggestive evidence results in a branching fraction B(Z ' →e + e - )≅2 endash 4%. The expected cross sections and branching ratios could give a few events in the present data and we speculate on the connection to the three e + e - events observed at Fermilab with large dielectron invariant mass. copyright 1998 The American Physical Society

Precision calculations in supersymmetric extensions of the Standard Model

International Nuclear Information System (INIS)

Slavich, P.

2013-01-01

This dissertation is organized as follows: in the next chapter I will summarize the structure of the supersymmetric extensions of the standard model (SM), namely the MSSM (Minimal Supersymmetric Standard Model) and the NMSSM (Next-to-Minimal Supersymmetric Standard Model), I will provide a brief overview of different patterns of SUSY (supersymmetry) breaking and discuss some issues on the renormalization of the input parameters that are common to all calculations of higher-order corrections in SUSY models. In chapter 3 I will review and describe computations on the production of MSSM Higgs bosons in gluon fusion. In chapter 4 I will review results on the radiative corrections to the Higgs boson masses in the NMSSM. In chapter 5 I will review the calculation of BR(B → X s γ in the MSSM with Minimal Flavor Violation (MFV). Finally, in chapter 6 I will briefly summarize the outlook of my future research. (author)

Globally and locally supersymmetric effective theories for light fields

CERN Document Server

Brizi, Leonardo; Scrucca, Claudio A

2009-01-01

We reconsider the general question of how to characterize most efficiently the low-energy effective theory obtained by integrating out heavy modes in globally and locally supersymmetric theories. We consider theories with chiral and vector multiplets and identify the conditions under which an approximately supersymmetric low-energy effective theory can exist. These conditions translate into the requirements that all the derivatives, fermions and auxiliary fields should be small in units of the heavy mass scale. They apply not only to the matter sector, but also to the gravitational one if present, and imply in that case that the gravitino mass should be small. We then show how to determine the unique exactly supersymmetric theory that approximates this effective theory at the lowest order in the counting of derivatives, fermions and auxiliary fields, by working both at the superfield level and with component fields. As a result we give a simple prescription for integrating out heavy superfields in an algebrai...

Coexistence of supersymmetric and supersymmetry-breaking states in spherical spin-glasses

International Nuclear Information System (INIS)

Annibale, Alessia; Gualdi, Giulia; Cavagna, Andrea

2004-01-01

The structure of states of the perturbed p-spin spherical spin-glass is analysed. At low enough free energy, metastable states have a supersymmetric structure, while at higher free energies the supersymmetry is broken. The transition between the supersymmetric and the supersymmetry-breaking phase is triggered by a change in the stability of states

Unification of reactor elastomeric sealing based on material

International Nuclear Information System (INIS)

Sinha, N.K.; Raj, Baldev

2012-01-01

The unification of elastomeric sealing applications of Indian nuclear reactors based on a few qualified fluoroelastomer/perfluoroelastomer compounds and standardized approaches for finite element analysis (FEA) based design, manufacturing process and antifriction coatings is discussed. It is shown that the advance polymer architecture based Viton ® formulation developed for inflatable seals of 500 MWe Prototype Fast Breeder Reactor (PFBR) and its four basic variations can encompass other sealing applications of PFBR with minimum additional efforts on development and validation. Changing the blend ratio of Viton ® GBL 200S and 600S in inflatable seal formulation could extend its use to Pressurized Heavy Water Reactors (PHWRs). The higher operating temperature of Advanced Heavy Water Reactor (AHWR) seals expands the choice to perfluoroelastomers. FEA based on plane-strain/axisymmetric modeling (with Mooney–Rivlin as the basic constitutive model), seal manufacture by cold feed extrusion and injection molding as well as plasma Teflon-like coating belonging to two variations obtained from the development of inflatable seals provide the necessary standardization for unification. The gains in simplification of design, development and operation of seals along with the enhancements of safety and reliability are expected to be substantial.

Unification of three linear models for the transient visual system

NARCIS (Netherlands)

Brinker, den A.C.

1989-01-01

Three different linear filters are considered as a model describing the experimentally determined triphasic impulse responses of discs. These impulse responses arc associated with the transient visual system. Each model reveals a different feature of the system. Unification of the models is

Searches for supersymmetric partners of third-generation quarks with CMS

CERN Document Server

Jansova, Marketa

2017-01-01

Supersymmetric partners of top and bottom quarks are among the most promising candidates for the next-to-lightest supersymmetric particle. Searches for the pair production of top and bottom squarks have been performed in final states with 0, 1, or 2 charged leptons, jets, and missing transverse energy. The results are obtained using proton-proton collisions at $\\sqrt{s}$ = 13 TeV, recorded by the CMS experiment in 2016.

Extended supersymmetric BMS{sub 3} algebras and their free field realisations

Energy Technology Data Exchange (ETDEWEB)

Banerjee, Nabamita [Indian Institute of Science Education and Research,Homi Bhabha Road, Pashan, Pune 411 008 (India); Jatkar, Dileep P. [Harish-Chandra Research Institute,Chhatnag Road, Jhusi, Allahabad, 211019 (India); Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 400085 (India); Lodato, Ivano; Mukhi, Sunil; Neogi, Turmoli [Indian Institute of Science Education and Research,Homi Bhabha Road, Pashan, Pune 411 008 (India)

2016-11-09

We study N=(2,4,8) supersymmetric extensions of the three dimensional BMS algebra (BMS{sub 3}) with most generic possible central extensions. We find that N-extended supersymmetric BMS{sub 3} algebras can be derived by a suitable contraction of two copies of the extended superconformal algebras. Extended algebras from all the consistent contractions are obtained by scaling left-moving and right-moving supersymmetry generators symmetrically, while Virasoro and R-symmetry generators are scaled asymmetrically. On the way, we find that the BMS/GCA correspondence does not in general hold for supersymmetric systems. Using the β-γ and the b-c systems, we construct free field realisations of all the extended super-BMS{sub 3} algebras.

Law behind second law of thermodynamics - unification with cosmology

International Nuclear Information System (INIS)

Nielsen, Holger B.; Ninomiya, Masao

2006-01-01

In an abstract setting of a general classical mechanical system as a model for the universe we set up a general formalism for a law behind the second law of thermodynamics, i.e. really for 'initial conditions'. We propose a unification with the other laws by requiring similar symmetry and locality properties

Applications of supersymmetric quantum mechanics

International Nuclear Information System (INIS)

Rietdijk, R.H.

1992-01-01

The central subject of the thesis is the spinning particle model. It is a theory describing in a pseudoclassical way a Dirac particle which moves in an arbitrary d-dimensional space-time.In addition to space-time coordinates, the particle has spin which is described in terms of anti-commuting coordinates. Along the particles world line there is a super-symmetry between the fermionic spin variables and the bosonic position coordinates of the particle. It is straightforward to quantisize this model giving rise to supersymmetric quantum mechanics. The model does indeed describe a particle with spin 1/2, like a quark or an electron. There are two aspects of this model which is studied extensively in this thesis. First, to investigate the symmetries of the spinning particle on an arbitrary Riemannian manifold. Second, attention is drawn to the application of supersymmetric quantum mechanical models (i.e. spinning particle models) defined on an arbitrary Riemannian manifold to the calculation of anomalies in quantum field theories defined on the same manifold. (author). 49 refs.; 7 figs

Higher-order predictions for supersymmetric particle decays

Energy Technology Data Exchange (ETDEWEB)

Landwehr, Ananda Demian Patrick

2012-06-12

We analyze particle decays including radiative corrections at the next-to-leading order (NLO) within the Minimal Supersymmetric Standard Model (MSSM). If the MSSM is realized at the TeV scale, squark and gluino production and decays yield relevant rates at the LHC. Hence, in the first part of this thesis, we compute decay widths including QCD and electroweak NLO corrections to squark and gluino decays. Furthermore, the Higgs sector of the MSSM is enhanced compared to the one of the Standard Model. Thus, the additional Higgs bosons decay also into supersymmetric particles. These decays and the according NLO corrections are analyzed in the second part of this thesis. The calculations are performed within a common renormalization framework and numerically evaluated in specific benchmark scenarios.

Supersymmetric construction of exactly solvable potentials and nonlinear algebras

International Nuclear Information System (INIS)

Junker, G.; Roy, P.

1998-01-01

Using algebraic tools of supersymmetric quantum mechanics we construct classes of conditionally exactly solvable potentials being the supersymmetric partners of the linear or radial harmonic oscillator. With the help of the raising and lowering operators of these harmonic oscillators and the SUSY operators we construct ladder operators for these new conditionally solvable systems. It is found that these ladder operators together with the Hamilton operator form a nonlinear algebra which is of quadratic and cubic type for the SUSY partners of the linear and radial harmonic oscillator

Supercurrent and the Adler-Bardeen theorem in coupled supersymmetric Yang-Mills theories

International Nuclear Information System (INIS)

Ensign, P.W.

1987-01-01

By the Adler-Bardeen theorem, only one-loop Feynman diagrams contribute to the anomalous divergences of quantum axial currents. The anomalous nature of scale transformations is manifested by an anomalous trace of the energy-momentum tensor, T/sup μ//sub μ/. Renormalization group arguments show that the quantum T/sup μ//sub μ/ must be proportional to the β-function. Since the β-function receives contributions at all loop levels, the Adler-Bardeen theorem appears to conflict with supersymmetry. Recently Grisaru, Milewski and Zanon constructed a supersymmetric axial current for pure supersymmetric Yang-Mills theory which satisfies the Adler-Bardeen theorem to two-loops. They used supersymmetric background field theory and regularization by dimensional reduction to maintain manifest supersymmetry and gauge invariance. In this thesis, their construction is extended to supersymmetric Yang-Mills theory coupled to chiral matter fields. The Adler-Bardeen theorem is then proven to all orders in perturbation theory for both the pure and coupled theories. The extension to coupled supersymmetric Yang-Mills supports the general validity of these techniques, and adds considerable insight into the structure of the anomalies. The all orders proof demonstrates that there is no conflict between supersymmetry and the Adler-Bardeen theorem

Problems of CP-violation in early unification theories

International Nuclear Information System (INIS)

Liparteliani, A.G.; Monich, V.A.; Volkov, G.G.

1985-01-01

The present work studies possible mechanisms of P and CP-violation in the frames of an approach based on early unification of fundamental local symmetries, i.e., Pati-Salam four-colour symmetry, extended weak isotopic symmetry and that of quark-lepton generations. The work also studies the influence of generations mixing on the rates of rare processes in each of 3 classes of interactions

Composite quarks and leptons from dynamical supersymmetry breaking without messengers

International Nuclear Information System (INIS)

Arkani-Hamed, N.; Luty, M.A.; Terning, J.

1998-01-01

We present new theories of dynamical supersymmetry breaking in which the strong interactions that break supersymmetry also give rise to composite quarks and leptons with naturally small Yukawa couplings. In these models, supersymmetry breaking is communicated directly to the composite fields without open-quotes messengerclose quotes interactions. The compositeness scale can be anywhere between 10thinspTeV and the Planck scale. These models can naturally solve the supersymmetric flavor problem, and generically predict sfermion mass unification independent from gauge unification. copyright 1998 The American Physical Society

Defect networks and supersymmetric loop operators

Energy Technology Data Exchange (ETDEWEB)

Bullimore, Mathew [Perimeter Institute for Theoretical Physics, 31 Caroline Street North, Waterloo, ON N2L 2Y5 (Canada)

2015-02-10

We consider topological defect networks with junctions in A{sub N−1} Toda CFT and the connection to supersymmetric loop operators in N=2 theories of class S on a four-sphere. Correlation functions in the presence of topological defect networks are computed by exploiting the monodromy of conformal blocks, generalising the notion of a Verlinde operator. Concentrating on a class of topological defects in A{sub 2} Toda theory, we find that the Verlinde operators generate an algebra whose structure is determined by a set of generalised skein relations that encode the representation theory of a quantum group. In the second half of the paper, we explore the dictionary between topological defect networks and supersymmetric loop operators in the N=2{sup ∗} theory by comparing to exact localisation computations. In this context, the the generalised skein relations are related to the operator product expansion of loop operators.

Supersymmetric quantum mechanics in three-dimensional space, 1

International Nuclear Information System (INIS)

Ui, Haruo

1984-01-01

As a direct generalization of the model of supersymmetric quantum mechanics by Witten, which describes the motion of a spin one-half particle in the one-dimensional space, we construct a model of the supersymmetric quantum mechanics in the three-dimensional space, which describes the motion of a spin one-half particle in central and spin-orbit potentials in the context of the nonrelativistic quantum mechanics. With the simplest choice of the (super) potential, this model is shown to reduce to the model of the harmonic oscillator plus constant spin-orbit potential of unit strength of both positive and negative signs, which was studied in detail in our recent paper in connection with ''accidental degeneracy'' as well as the ''graded groups''. This simplest model is discussed in some detail as an example of the three-dimensional supersymmetric quantum mechanical system, where the supersymmetry is an exact symmetry of the system. More general choice of a polynomial superpotential is also discussed. It is shown that the supersymmetry cannot be spontaneously broken for any polynomial superpotential in our three-dimensional model; this result is contrasted to the corresponding one in the one-dimensional model. (author)

Generalized symmetries of an 𝓝 = 1 supersymmetric Boiti-Leon-Manna-Pempinelli system

Science.gov (United States)

Wang, Jian-Yong; Tang, Xiao-Yan; Liang, Zu-Feng; Lou, Sen-Yue

2015-05-01

The formal series symmetry approach (FSSA), a quite powerful and straightforward method to establish infinitely many generalized symmetries of classical integrable systems, has been successfully extended in the supersymmetric framework to explore series of infinitely many generalized symmetries for supersymmetric systems. Taking the 𝒩 = 1 supersymmetric Boiti-Leon-Manna-Pempinelli system as a concrete example, it is shown that the application of the extended FSSA to this supersymmetric system leads to a set of infinitely many generalized symmetries with an arbitrary function f (t). Some interesting special cases of symmetry algebras are presented, including a limit case f (t) = 1 related to the commutativity of higher order generalized symmetries. Project supported by the National Natural Science Foundation of China (Grant Nos. 11275123, 11175092, 11475052, and 11435005), the Shanghai Knowledge Service Platform for Trustworthy Internet of Things, China (Grant No. ZF1213), and the Talent Fund and K CWong Magna Fund in Ningbo University, China.

Hamiltonian reduction and supersymmetric mechanics with Dirac monopole

International Nuclear Information System (INIS)

Bellucci, Stefano; Nersessian, Armen; Yeranyan, Armen

2006-01-01

We apply the technique of Hamiltonian reduction for the construction of three-dimensional N=4 supersymmetric mechanics specified by the presence of a Dirac monopole. For this purpose we take the conventional N=4 supersymmetric mechanics on the four-dimensional conformally-flat spaces and perform its Hamiltonian reduction to three-dimensional system. We formulate the final system in the canonical coordinates, and present, in these terms, the explicit expressions of the Hamiltonian and supercharges. We show that, besides a magnetic monopole field, the resulting system is specified by the presence of a spin-orbit coupling term. A comparision with previous work is also carried out

Theoretical scenarios for 103 GeV to 1019 GeV

International Nuclear Information System (INIS)

Kaul, R.K.

1996-01-01

Basic dogmas of particle physics are reviewed. Some of their implications beyond the standard model are explored. Higgs sector of the standard model of electroweak interactions is the weakest link in the model. Elementary Higgs field makes the model unnatural beyond about 10 3 GeV. Supersymmetry provides the most attractive framework where in this problem can be addressed. This new symmetry, relating fermions and bosons, is expected to be operative at about 10 3 GeV. In addition, grand unification of the fundamental interactions can be studied consistently only within a supersymmetric formulation. Inclusion of gravity with other interactions leads to supergravity theories, which should emerge as a low energy description of a more fundamental theory, the string-theory. Supersymmetry again is an essential feature of such a theory. Quantum gravity, with its characteristic scale of 10 19 GeV, may well be described by a superstring theory. (author). 28 refs., 1 fig

Radiative electroweak breaking with pseudo Goldstone Higgs doublets

International Nuclear Information System (INIS)

Ananthanarayan, B.; Shafi, Q.

1996-01-01

We consider a realistic example of supersymmetric grand unification based on SU(3) c xSU(3) L xSU(3) R in which the electroweak (EW) Higgs doublets are open-quote open-quote light close-quote close-quote as a consequence of the open-quote open-quote pseudo Goldstone close-quote close-quote mechanism. We discuss radiative EW breaking in this model, exploring in particular the open-quote open-quote small close-quote close-quote (order unity) and open-quote open-quote large close-quote close-quote (≅m t /m b ) tanβ regions by studying the variations of r 2 (≡μ 1,2 2 /μ 2 3 ), where μ 1,2,3 2 are the well-known MSSM parameters evaluated at the GUT scale. For |r| sufficiently close to unity the quantity tanβ can be of order unity, but the converse is not always true. copyright 1996 The American Physical Society

Spontaneous B-L breaking as the origin of the hot early universe

Energy Technology Data Exchange (ETDEWEB)

Buchmueller, W.; Domcke, V.; Schmitz, K.

2012-03-15

The decay of a false vacuum of unbroken B-L symmetry is an intriguing and testable mechanism to generate the initial conditions of the hot early universe. If B-L is broken at the grand unification scale, the false vacuum phase yields hybrid inflation, ending in tachyonic preheating. The dynamics of the B - L breaking Higgs field and thermal processes produce an abundance of heavy neutrinos whose decays generate entropy, baryon asymmetry and gravitino dark matter. We study the phase transition for the full supersymmetric Abelian Higgs model. For the subsequent reheating process we give a detailed time-resolved description of all particle abundances. The competition of cosmic expansion and entropy production leads to an intermediate period of constant 'reheating' temperature, during which baryon asymmetry and dark matter are produced. Consistency of hybrid inflation, leptogenesis and gravitino dark matter implies relations between neutrino parameters and superparticle masses, in particular a lower bound on the gravitino mass of 10 GeV.

Leptogenesis in a Δ(27)×SO(10) SUSY GUT

Energy Technology Data Exchange (ETDEWEB)

Björkeroth, Fredrik [School of Physics and Astronomy, University of Southampton,SO17 1BJ Southampton (United Kingdom); Anda, Francisco J. de [Departamento de Física, CUCEI, Universidad de Guadalajara,Guadalajara (Mexico); Varzielas, Ivo de Medeiros; King, Stephen F. [School of Physics and Astronomy, University of Southampton,SO17 1BJ Southampton (United Kingdom)

2017-01-17

Although SO(10) Supersymmetric (SUSY) Grand Unification Theories (GUTs) are very attractive for neutrino mass and mixing, it is often quite difficult to achieve successful leptogenesis from the lightest right-handed neutrino N{sub 1} due to the strong relations between neutrino and up-type quark Yukawa couplings. We show that in a realistic model these constraints are relaxed, making N{sub 1} leptogenesis viable. To illustrate this, we calculate the baryon asymmetry of the Universe Y{sub B} from flavoured N{sub 1} leptogenesis in a recently proposed Δ(27)×SO(10) SUSY GUT. The flavoured Boltzmann equations are solved numerically, and comparison with the observed Y{sub B} places constraints on the allowed values of right-handed neutrino masses and neutrino Yukawa couplings. The flavoured SO(10) SUSY GUT is not only fairly complete and predictive in the lepton sector, but can also explain the BAU through leptogenesis with natural values in the lepton sector albeit with some tuning in the quark sector.

Profumo di SUSY: Suggestive Correlations in the ATLAS and CMS High Jet Multiplicity Data

CERN Document Server

Li, Tianjun; Nanopoulos, Dimitri V; Walker, Joel W

2011-01-01

We present persistently amassing evidence that the CMS and ATLAS Collaborations may indeed be already registering supersymmetry events at the Large Hadron Collider (LHC). Our analysis is performed in the context of a highly phenomenologically favorable model named No-Scale F-SU(5), which represents the unification of the F-lipped SU(5) Grand Unified Theory (GUT), two pairs of hypothetical TeV-scale vector-like supersymmetric multiplets derived out of F-Theory, and the dynamically established boundary conditions of No-Scale supergravity. We document highly suggestive correlations between the first inverse femtobarn of observations by CMS and ATLAS, where seductive excesses in multijet events, particularly those with nine or more jets, are unambiguously accounted for by a precision Monte-Carlo simulation of the F-SU(5) model space. This intimate correspondence is optimized by a unified gaugino mass in the neighborhood of M_{1/2}=518 GeV. We supplement this analysis by extrapolating for the expected data profile...