Topology change from Kaluza-Klein dimensions
Ionicioiu, R
1997-01-01
In this letter we show that in a Kaluza-Klein framework we can have arbitrary topology change between the macroscopic (i.e. noncompactified) spacelike 3-hypersurfaces. This is achieved by using the compactified dimensions as a catalyser for topology change. In the case of odd-dimensional spacetimes (such as the 11-dimensional M-theory) this is always possible. In the even-dimensional case, a sufficient condition is the existence of a closed, odd-dimensional manifold as a factor (such as S^1, S^3) in the Kaluza-Klein sector. Since one of the most common manifolds used for compactification is the torus T^k = S^1 \\times ... \\times S^1, in this case we can again induce an arbitrary topology change on the 3-hypersurfaces.
Kaluza-Klein Theory without Extra Dimensions: Curved Clifford Space
Pavsic, M
2005-01-01
A theory in which 16-dimensional curved Clifford space (C-space) provides realization of Kaluza-Klein theory is investigated. No extra dimensions of spacetime are needed: "extra dimensions" are in C-space. It is shown that the covariant Dirac equation in C-space contains Yang-Mills fields of the U(1)xSU(2)xSU(3) group as parts of the generalized spin connection of the C-space.
Ishigure, Yoshiaki; Santa, Akiteru
2016-01-01
Universal extra dimension models with Kaluza-Klein parity provide us excellent candidates for dark matter. We consider phenomenological universal extra dimension models where the Kaluza-Klein (KK) mass spectrum is different from that of the minimal universal extra dimension model, and compute the thermal relic abundance of the first KK mode of the photon taking into account the production of second KK particles. It is pointed out that its thermal relic abundance depends significantly on the mass degeneracy between the KK-photon and other KK particles because of considerable coannihilation effects. The cosmologically favored compactification scale is shown to range from around 1 TeV to a few TeV even in the cases where one of the first KK particles is tightly degenerate with the first KK photon in mass.
The second Kaluza-Klein neutral Higgs bosons in the minimal Universal Extra Dimension model
Chang, Sanghyeon; Song, Jeonghyeon
2011-01-01
Loop-induced decays of a neutral Higgs boson into a pair of gluon or photon have great implications for the Higgs discovery at the LHC. If the Higgs boson is heavy with mass above $\\sim 500\\gev$, however, these radiative branching ratios are very suppressed in the standard model, as the new decay channels are kinematically open. We note that these radiative decays can be sizable for the heavy second Kaluza-Klein (KK) CP-even $h^\\tw$ and CP-odd $\\chi^\\tw$ modes of the Higgs boson in the minimal universal extra dimension (mUED) model with the KK parity conservation: highly degenerate mass spectrum of the theory prohibits kinematically the dominant KK-number conserving decays into the first KK modes of the $W$, $Z$ and top quark. We find that $h^{(2)} \\to g g$ is absent at one loop level since $h^{(2)}$ couples with different mass eigenstates of $t_{1,2}^\\on$ while the gluon with the same mass eigenstates. The $h^\\tw$ production at the LHC is very suppressed. On the contrary, we have ${\\rm BR} (\\chi^\\tw \\to g g)...
New supernova limit on large extra dimensions: bounds on Kaluza-Klein graviton production.
Hannestad, S; Raffelt, G G
2001-07-30
If large extra dimensions exist in nature, supernova (SN) cores will emit large fluxes of Kaluza-Klein gravitons, producing a cosmic background of these particles with energies and masses up to about 100 MeV. Radiative decays then give rise to a diffuse cosmic gamma-ray background with E(gamma) approximately less than 100 MeV which is well in excess of the observations if more than 0.5%-1% of the SN energy is emitted into the new channel. For two extra dimensions we derive a conservative bound on their radius of R approximately less than 0.9 x 10(-4) mm; for three extra dimensions it is R approximately less than 1.9 x 10(-7) mm.
Dynamical fermion masses under the influence of Kaluza-Klein fermions in extra dimensions
Abe, Hiroyuki; Miguchi, Hironori; Muta, Taizo
2000-01-01
The dynamical fermion mass generation in the 4-dimensional brane is discussed in a model with 5-dimensional Kaluza-Klein fermions in interaction with 4-dimensional fermions. It is found that the dynamical fermion masses are generated beyond the critical radius of the compactified extra dimensional space and may be made small compared with masses of the Kaluza-Klein modes.
Dynamical fermion masses under the influence of Kaluza-Klein fermions in extra dimensions
Abe, H; Muta, T; Abe, Hiroyuki; Miguchi, Hironori; Muta, Taizo
2000-01-01
The dynamical fermion mass generation in the 4-dimensional brane is discussedin a model with 5-dimensional Kaluza-Klein fermions in interaction with4-dimensional fermions. It is found that the dynamical fermion masses aregenerated beyond the critical radius of the compactified extra dimensionalspace and may be made small compared with masses of the Kaluza-Klein modes.
Construction of a Kaluza-Klein type Theory from One Dimension
Jackson, David J
2016-01-01
We describe how a physical theory incorporating the properties of fields deriving from extra-dimensional structures over a four-dimensional spacetime manifold can in principle be obtained through the analysis of a simple initial structure consisting of the one dimension of time alone, as represented by the real line. The simplicity of this starting point leads to symmetries of multi-dimensional forms of time, from which a geometrical structure can be derived which is similar to the framework employed in non-Abelian Kaluza-Klein theories. This leads to a relationship between the external and internal curvature on the spacetime manifold unified through the underlying constraint of the one dimension of time for the theory presented here. We also describe how the symmetry breaking structure is compatible with the Coleman-Mandula theorem for the subsequent quantisation of the theory.
Electroweak Kaluza-Klein Dark Matter
Flacke, Thomas; Kang, Dong Woo; Kong, Kyoungchul; Mohlabeng, Gopolang; Park, Seong Chan
2017-01-01
In models with universal extra dimensions (UED), the lightest Kaluza-Klein excitation of neutral electroweak gauge bosons is a stable, weakly interacting massive particle and thus is a candidate for dark matter thanks to Kaluza-Klein parity. We examine concrete model realizations of such dark matter in the context of non-minimal UED extensions. The boundary localized kinetic terms for the electroweak gauge bosons lead to a non-trivial mixing among the first Kaluza-Klein excitations of the ${\\...
Quantum Kaluza-Klein Compactification
Sochichiu, C.
1999-01-01
Kaluza--Klein compactification in quantum field theory is analysed from the perturbation theory viewpoint. Renormalisation group analysis for compactification size dependence of the coupling constant is proposed.
Electroweak Kaluza-Klein Dark Matter
Energy Technology Data Exchange (ETDEWEB)
Flacke, Thomas [IBS, Daejeon; Kang, Dong Woo [Sungkyunkwan U.; Kong, Kyoungchul [Pittsburgh U.; Mohlabeng, Gopolang [U. Kansas, Lawrence; Park, Seong Chan [Korea Inst. Advanced Study, Seoul
2017-02-09
In models with universal extra dimensions (UED), the lightest Kaluza-Klein excitation of neutral electroweak gauge bosons is a stable, weakly interacting massive particle and thus is a candidate for dark matter thanks to Kaluza-Klein parity. We examine concrete model realizations of such dark matter in the context of non-minimal UED extensions. The boundary localized kinetic terms for the electroweak gauge bosons lead to a non-trivial mixing among the first Kaluza-Klein excitations of the ${\\rm SU}(2)_W$ and ${\\rm U}(1)_Y$ gauge bosons and the resultant low energy phenomenology is rich. We investigate implications of various experiments including low energy electroweak precision measurements, direct and indirect detection of dark matter particles and direct collider searches at the LHC. Notably, we show that the electroweak Kaluza-Klein dark matter can be as heavy as 2.4 TeV, which is significantly higher than $1.3$ TeV as is indicated as an upper bound in the minimal UED model.
Di Troia, Claudio
2016-01-01
The non perturbative guiding center transformation [Di Troia C., Phys. Plasmas 22, 042103 (2015)] is extended to the relativistic regime. The single particle dynamic is described in the Minkowski flat space-time. The main solutions are obtained in covariant form: the gyrating particle solutions and the guiding particle solution, both in gyro-kinetic as in MHD orderings. It is shown the relevance of the ideal Ohm's law in the context of the guiding center transformation. Moreover, it is also considered the presence of a gravitational field. The way to introduce the gravitational field is original and based on the Einstein conjecture on the feasibility to extend the general relativity theory to include electromagnetism. In gyro-kinetic theory, some interesting novelties appear in a natural way, such as the exactness of the conservation of magnetic moment, or the fact that the gyro-phase is treated as the non observable fifth dimension of the Kaluza-Klein model.
Kaluza-Klein thresholds and regularization (in)dependence
Energy Technology Data Exchange (ETDEWEB)
Kubo, Jisuke; Terao, Haruhiko; Zoupanos, George
2000-05-15
We present a method to control the regularization scheme dependence in the running of couplings in Kaluza-Klein theories. Specifically we consider the scalar theory in five dimensions, assuming that one dimension is compactified, and we study various regularization schemes in order to analyze concretely the regularization scheme dependence of the Kaluza-Klein threshold effects. We find that in one-loop order, although the {beta}-functions are different for the different schemes, the net difference in the running of the coupling among the different schemes is very small for the entire range of energies. Our results have been extended to include more than one radius, and the gauge coupling unification is re-examined. Strings are also used as a regulator. We obtain a particular regularization scheme of the effective field theory which can accurately describe the string Kaluza-Klein threshold effects.
Kaluza-Klein theory for teleparallel gravity
Geng, Chao-Qiang; Luo, Ling-Wei; Tseng, Huan-Hsin
2014-01-01
We study teleparallel gravity in the \\emph{original} Kaluza-Klein (KK) scenario. Our calculation of the KK reduction of teleparallel gravity indicates that the 5-dimensional torsion scalar $^{(5)}T$ generates the non-Brans-Dicke type effective Lagrangian in 4-dimension due to an additional coupling between the derivative of the scalar field and torsion, but the result is equivalent to that in general relativity. We also discuss the cosmological behavior in the FLRW universe based on the effective teleparallel gravity.
From Taub-NUT to Kaluza-Klein magnetic monopole
Riazi, Nematollah; Hashemi, S. Sedigheh
2016-03-01
We present a Kaluza-Klein vacuum solution which closely resembles the Taub-NUT magnetic monopole and we investigate its physical properties as viewed from four space-time dimensions. We show that the Taub-NUT Kaluza-Klein vacuum solution in five dimensions is a static magnetic monopole. We find that the four dimensional matter properties do not obey the equation of state of radiation and there is no event horizon. A comparison with the available magnetic monopole solutions and the issue of vanishing and negative mass are discussed.
Charged rotating dilaton black holes with Kaluza-Klein asymptotics
Knoll, Christian; Nedkova, Petya
2016-03-01
We construct a class of stationary and axisymmetric solutions to the five-dimensional Einstein-Maxwell-dilaton gravity, which describe configurations of charged rotating black objects with Kaluza-Klein asymptotics. The solutions are constructed by uplifting a vacuum seed solution to six dimensions, performing a boost and a subsequent circle reduction. We investigate the physical properties of the charged solutions and obtain their general relations to the properties of the vacuum seed. We also derive the gyromagnetic ratio and the Smarr-like relations. As particular cases, we study three solutions, which describe a charged rotating black string, a charged rotating black ring on Kaluza-Klein bubbles, and a superposition of two black holes and a Kaluza-Klein bubble.
The massive Kaluza-Klein monopole
Bergshoeff, E; Eyras, E; Lozano, Y
1998-01-01
We construct the (bosonic) effective worldvolume action of an M-theory Kaluza-Klein monopole in a background given by the bosonic sector of eleven-dimensional massive supergravity, i.e, a "massive Kaluza-Klein monopole". As a consistency check we show that the direct dimensional reduction along the
Stability of some Kaluza-Klein cosmological models
Energy Technology Data Exchange (ETDEWEB)
Barrow, J.D.; Stein-Schabes, J.
1986-02-06
The stability is examined of some exact Kaluza-Klein cosmological solutions that possess static extra dimensions and standard Friedman behaviour for the remaining three spatial dimensions. It is shown that even when the extra dimensions are asymptotically static they produce a deviation from Friedman behaviour in the observable three spatial dimensions. A similar effect is found for models with anisotropically expanding three-spaces. (orig.).
Topology change in Kaluza-Klein and superstring theories
Energy Technology Data Exchange (ETDEWEB)
Tipler, F.J.
1985-12-19
It is shown that topology change - for instance, true dynamical compactification - cannot occur in classical Kaluza-Klein and superstring theories without causality violation either in the form of a breakdown in predictability (a failure of global hyperbolicity), or in the form of closed timelike curves. This implies that if causality holds, then any toplogical distinction between the spacetime and internal dimensions either has to be present ab initio, or else must arise in the quantum gravity regime. (orig.).
Topology change in Kaluza-Klein and superstring theories
Tipler, Frank J.
1985-12-01
It is shown that topology change-for instance, true dynamical compactification - cannot occur in classical Kaluza-Klein and superstring theories without causality violation either in the form of a breakdown in predictability (a failure of global hyperbolicity), or in the form of closed timelike curves. This implies that if causality holds, then any topological distinction between the spacetime and internal dimensions either has to be present ab initio, or else must arise in the quantum gravity regime. Permanent address.
Kaluza-Klein relics from warped reheating
Berndsen, Aaron; Stoica, Horace
2007-01-01
It has been suggested that after brane-antibrane inflation in a Klebanov-Strassler (KS) warped throat, metastable Kaluza-Klein (KK) excitations can be formed due to nearly-conserved angular momenta along isometric directions in the throat. If sufficiently long-lived, these relics could conflict with big bang nucleosynthesis or baryogenesis by dominating the energy density of the universe. We make a detailed estimate of the decay rate of such relics using the low energy effective action of type IIB string theory compactified on the throat geometry, with attention to powers of the warp factor. We find that it is necessary to turn on SUSY-breaking deformations of the KS background in order to ensure that the most dangerous relics will decay. The decay rate is found to be much larger than the naive guess based on the dimension of the operators which break the angular isometries of the throat. For an inflationary warp factor of order w ~ 10^{-4}, we obtain the bound M_{3/2} > 10^8 GeV on the scale of SUSY breaking...
Phases of Kaluza-Klein black holes
DEFF Research Database (Denmark)
Elvang, Henriette; Obers, Niels; Harmark, Troels
2004-01-01
We review the latest progress in understanding the phase structure of static and neutral Kaluza-Klein black holes, i.e. static and neutral solutions of pure gravity with an event horizon and with asymptotics Md × S1, Md being d-dimensional Minkowski space.......We review the latest progress in understanding the phase structure of static and neutral Kaluza-Klein black holes, i.e. static and neutral solutions of pure gravity with an event horizon and with asymptotics Md × S1, Md being d-dimensional Minkowski space....
Phases of Kaluza-Klein black holes
DEFF Research Database (Denmark)
Elvang, Henriette; Obers, Niels; Harmark, Troels
2004-01-01
We review the latest progress in understanding the phase structure of static and neutral Kaluza-Klein black holes, i.e. static and neutral solutions of pure gravity with an event horizon and with asymptotics Md × S1, Md being d-dimensional Minkowski space.......We review the latest progress in understanding the phase structure of static and neutral Kaluza-Klein black holes, i.e. static and neutral solutions of pure gravity with an event horizon and with asymptotics Md × S1, Md being d-dimensional Minkowski space....
Angular Momentum-Free of the Entropy Relations for Rotating Kaluza-Klein Black Holes
Liu, Hang; Meng, Xin-he
2017-02-01
Based on a mathematical lemma related to the Vandermonde determinant and two theorems derived from the first law of black hole thermodynamics, we investigate the angular momentum independence of the entropy sum as well as the entropy product of general rotating Kaluza-Klein black holes in higher dimensions. We show that for both non-charged rotating Kaluza-Klein black holes and non-charged rotating Kaluza-Klein-AdS black holes, the angular momentum of the black holes will not be present in entropy sum relation in dimensions d≥4, while the independence of angular momentum of the entropy product holds provided that the black holes possess at least one zero rotation parameter a j = 0 in higher dimensions d≥5, which means that the cosmological constant does not affect the angular momentum-free property of entropy sum and entropy product under the circumstances that charge δ=0. For the reason that the entropy relations of charged rotating Kaluza-Klein black holes as well as the non-charged rotating Kaluza-Klein black holes in asymptotically flat spacetime act the same way, it is found that the charge has no effect in the angular momentum-independence of entropy sum and product in asymptotically flat spactime.
On the Stability of Squashed Kaluza-Klein Black Holes
Kimura, Masashi; Murata, Keiju; Ishihara, Hideki; Soda, Jiro
2007-01-01
The stability of squashed Kaluza-Klein black holes is studied. The squashed Kaluza-Klein black hole looks like five dimensional black hole in the vicinity of horizon and four dimensional Minkowski spacetime with a circle at infinity. In this sense, squashed Kaluza-Klein black holes can be regarded as black holes in the Kaluza-Klein spacetimes. Using the symmetry of squashed Kaluza-Klein black holes, $SU(2)\\times U(1)\\simeq U(2)$, we obtain master equations for a part of the metric perturbatio...
From Taub-NUT to Kaluza-Klein magnetic monopole
Riazi, Nematollah
2016-01-01
We present a Kaluza-Klien vacuum solution which closely resembles the Taub-NUT magnetic monopole and we investigate its physical properties as viewed from four space-time dimensions. We show that the Taub-NUT Kaluza-Klein vacuum solution in five dimensions is a static magnetic monopole. We find that the four dimensional matter properties do not obey the equation of state of radiation and there is no event horizon. A comparison with the available magnetic monopole solutions and the issue of vanishing and negative mass are discussed.
Kaluza-Klein Masses and Couplings: Radiative Corrections to Tree-Level Relations
Bauman, Sky
2011-01-01
The most direct experimental signature of a compactified extra dimension is the appearance of towers of Kaluza-Klein particles obeying specific mass and coupling relations. However, such masses and couplings are subject to radiative corrections. In this paper, using techniques developed in previous work, we investigate the extent to which such radiative corrections deform the expected tree-level relations between Kaluza-Klein masses and couplings. As toy models for our analysis, we investigate a flat five-dimensional scalar \\lambda\\phi^4 model and a flat five-dimensional Yukawa model involving both scalars and fermions. In each case, we identify the conditions under which the tree-level relations are stable to one-loop order, and the situations in which radiative corrections modify the algebraic forms of these relations. Such corrections to Kaluza-Klein spectra therefore have the potential to distort the apparent geometry of a large extra dimension.
The classical tests in Kaluza-Klein gravity
Kalligas, D.; Wesson, P. S.; Everitt, C. W. F.
1995-01-01
The possible existence of extra dimensions to spacetime can be tested astrophysically using Kaluza-Klein theory, which is a natural extension of Einsteins's general relativity. In the simplest version of the theory, there is a standard class of five-dimensional solutions that are analogous to the four-dimensional Schwarzschild solution. However, even a small departure of the extra dimension from flatness affects the first or dominant part of the potential, making it possible to test for the existence of an extra dimension. Data from the solar system indicate that in our region of space the terms due to the fifth dimension are small (less than or equal to 0.1%) compared to those due to the usual for dimensions of spacetime. However, the parameters of Kaluza-Klein theory are not universal constants and can vary from place to place depending on local physics. Hence other astrophysical systems may serve as better laboratories for investigating the possible existence of extra dimensions.
Strong Gravitational Lensing in a Charged Squashed Kaluza- Klein G\\"{o}del Black hole
Sadeghi, J
2013-01-01
In this paper we investigate the strong gravitational lansing in a charged squashed Kaluza-Klein G\\"{o}del black hole. The deflection angle is considered by the logarithmic term proposed by Bozza et al. Then we study the variation of deflection angle and its parameters $\\bar{a}$ and $\\bar{b}$ . We suppose that the supermassive black hole in the galaxy center can be considered by a charged squashed Kaluza-Klein black hole in a G\\"{o}del background and by relation between lensing parameters and observables we estimate the observables for different values of charge, extra dimension and G\\"{o}del parameters.
Strong gravitational lensing in a charged squashed Kaluza-Klein Gödel black hole
Sadeghi, J.; Naji, J.; Vaez, H.
2014-01-01
In this Letter we investigate the strong gravitational lansing in a charged squashed Kaluza-Klein Gödel black hole. The deflection angle is considered by the logarithmic term proposed by Bozza et al. Then we study the variation of deflection angle and its parameters abar and bbar. We suppose that the supermassive black hole in the galaxy center can be considered by a charged squashed Kaluza-Klein black hole in a Gödel background. Then by the relations between lensing parameters and observables, we estimate the observables for different values of charge, extra dimension and Gödel parameters.
Phases of Kaluza-Klein Black Holes
DEFF Research Database (Denmark)
Harmark, Troels; Obers, N. A.
2005-01-01
We review the latest progress in understanding the phase structure of static and neutral Kaluza-Klein black holes, i.e. static and neutral solutions of pure gravity with an event horizon that asymptote to a d-dimensional Minkowski-space times a circle. We start by reviewing the (mu,n) phase diagram...... and the split-up of the phase structure into solutions with an internal SO(d-1) symmetry and solutions with Kaluza-Klein bubbles. We then discuss the uniform black string, non-uniform black string and localized black hole phases, and how those three phases are connected, involving issues such as classical...... instability and horizon-topology changing transitions. Finally, we review the bubble-black hole sequences, their place in the phase structure and interesting aspects such as the continuously infinite non-uniqueness of solutions for a given mass and relative tension....
Cosmological applications in Kaluza-Klein theory
Institute of Scientific and Technical Information of China (English)
M. I. Wanas; Gamal G. L. Nashed; A. A. Nowaya
2012-01-01
The field equations of Kaluza-Klein (KK) theory have been applied in the domain of cosmology.These equations are solved for a flat universe by taking the gravitational and the cosmological constants as a function of time t.We use Taylor's expansion of cosmological function,△(t),up to the first order of the time t.The cosmological parameters are calculated and some cosmological problems are discussed.
Cosmological applications in Kaluza-Klein theory
Wanas, M I; Nowaya, A A
2011-01-01
The field equations of Kaluza-Klein (KK) theory have been applied in the domain of cosmology. These equations are solved for a flat universe by taking the gravitational and the cosmological constants as a function of time t. We use Taylor's expansion of cosmological function, $\\Lambda(t)$, up to the first order of the time $t$. The cosmological parameters are calculated and some cosmological problems are discussed.
Rotating cylindrically symmetric Kaluza-Klein ﬂuid model
Indian Academy of Sciences (India)
Ramesh Tikekar; L K Patel
2000-09-01
Kaluza-Klein ﬁeld equations for stationary cylindrically symmetric ﬂuid models in standard Einstein theory are formulated and a set of physically viable solutions is reported. This set is believed to be the ﬁrst such Kaluza-Klein solutions and it includes the Kaluza-Klein counterpart of Davidson’s solution describing spacetime of a perfect ﬂuid in rigid rotation about a regular axis.
On some developments in the Nonsymmetric Kaluza-Klein Theory
Energy Technology Data Exchange (ETDEWEB)
Kalinowski, M.W. [Warsaw University, Faculty of Physics, Warsaw (Poland); Pracownia Bioinformatyki, Instytut Medycyny Doswiadczalnej i Klinicznej PAN, Warszawa (Poland)
2014-03-15
We consider a condition for charge confinement and gravito-electromagnetic wave solutions in nonsymmetric Kaluza-Klein theory. We consider also the influence of the cosmological constant on a static, spherically symmetric solution. We remind the reader of some fundamentals of nonsymmetric Kaluza-Klein theory and the geometrical background behind the theory. Simultaneously we make some remarks concerning a misunderstanding connected to several notions of Kaluza-Klein Theory, Einstein Unified Field Theory, geometrization and unification of physical interactions. We reconsider the Dirac field in nonsymmetric Kaluza-Klein theory. (orig.)
On some developments in the Nonsymmetric Kaluza-Klein Theory
Kalinowski, M W
2014-01-01
We consider a condition for a charge confinement and gravito-electromagnetic wave solutions in the Nonsymmetric Kaluza-Klein Theory.We consider also an influence of a cosmological constant on a static,spherically symmetric solution.We remind to the reader some fudamentals of the Nonsymmetric Kaluza-Klein Theory and a geometrcal background behind the theory.Simultaneously we give some remarks concerning misunderstanding connected to several notions of the Nonsymmetric Kaluza-Klein Theory,Einstein Unified Field Theory,geometrization and unification of physical interactions .We reconsider Dirac field in the Nonsymmetric Kaluza-Klein Theory.
Single field inflationary models with non-compact Kaluza-Klein theory
Ledesma, D S; Ledesma, Diego S.; Bellini, Mauricio
2004-01-01
We discuss a semiclassical treatment to inflationary models from Kaluza-Klein theory without the cylinder condition. We conclude that the evolution of the early universe could be described by a geodesic trayectory of a cosmological 5D metric here proposed, so that the effective 4D FRW background metric should be a hypersurface on a constant fifth dimension.
Single field inflationary models with non-compact Kaluza-Klein theory
Energy Technology Data Exchange (ETDEWEB)
Ledesma, Diego S.; Bellini, Mauricio
2004-02-12
We discuss a semiclassical treatment to inflationary models from Kaluza-Klein theory without the cylinder condition. We conclude that the evolution of the early universe could be described by a geodesic trajectory of a cosmological 5D metric here proposed, so that the effective 4D FRW background metric should be a hypersurface on a constant fifth dimension.
Angular Momentum-Free of the Entropy Relations for Rotating Kaluza-Klein Black Holes
Liu, Hang
2016-01-01
Based on a mathematical lemma related to the Vandermonde determinant and two theorems derived from the first law of black hole thermodynamics, we investigate the angular momentum independence of the entropy sum as well as the entropy product of general rotating Kaluza-Klein black holes in higher dimensions. We show that for both non-charged rotating Kaluza-Klein black holes and non-charged rotating Kaluza-Klein-AdS black holes, the angular momentum of the black holes will not be present in entropy sum relation in dimensions $d\\geq4$, while the independence of angular momentum of the entropy product holds provided that the black holes possess at least one zero rotation parameter $a_j$ = 0 in higher dimensions $d\\geq5$, which means that the cosmological constant does not affect the angular momentum-free property of entropy sum and entropy product under the circumstances that charge $\\delta=0$. For the reason that the entropy relations of charged rotating Kaluza-Klein black holes as well as the non-charged rotat...
Kaluza-Klein mixmaster universes
Energy Technology Data Exchange (ETDEWEB)
Barrow, J.D.; Stein-Schabes, J.
1985-09-15
We analyze the behavior of some Bianchi type-IX, mixmaster cosmological models possessing extra dimensions. We find that, unlike the three-dimensional case, they do not exhibit chaotic behavior on approach to their initial singularity. A finite sequence of stochastic mixmaster oscillations is, in general, replaced by monotonic contraction of the three-space scale factors on approach to a singularity whenever additional spatial dimensions exist with the metric form we consider.
Thermodynamics in Kaluza-Klein Universe
Sharif, M
2014-01-01
This paper is devoted to check the validity of laws of thermodynamics for Kaluza-Klein universe in the state of thermal equilibrium, composed of dark matter and dark energy. The generalized holographic dark energy and generalized Ricci dark energy models are considered here. It is proved that the first and generalized second law of thermodynamics are valid on the apparent horizon for both of these models. Further, we take a horizon of radius $L$ with modified holographic or Ricci dark energy. We conclude that these models do not obey the first and generalized second law of thermodynamics on the horizon of fixed radius $L$ for a specific range of model parameters.
On Signature Transition and Compactification in Kaluza-Klein Cosmology
Darabi, F
1999-01-01
We consider an empty (4+1) dimensional Kaluza-Klein universe with a negative cosmological constant and a Robertson-Walker type metric. It is shown that the solutions to Einstein field equations have degenerate metric and exhibit transitioins from a Euclidean to a Lorentzian domain. We then suggest a mechanism, based on signature transition which leads to compactification of the internal space in the Lorentzian region as $a \\sim |\\Lambda|^{1/2}$. With the assumption of a very small value for the cosmological constant we find that the size of the universe $R$ and the internal scale factor $a$ would be related according to $Ra\\sim 1$ in the Lorentzian region. The corresponding Wheeler-DeWitt equation has exact solution in the mini-superspace giving rise to a quantum state which peaks in the vicinity of the classical solutions undergoing signature transition.
Kaluza-Klein Structure Associated With Fat Brane
Hung, P Q; Hung, Pham Quang; Tran, Ngoc-Khanh
2003-01-01
It is known that the imposition of orbifold boundary conditions on background scalar field can give rise to a non-trivial vacuum expectation value (VEV) along extra dimensions, which in turn generates fat branes and associated unconventional Kaluza-Klein (KK) towers of fermions. We study the structure of these KK towers in the limit of one large extra dimension and show that normalizable (bound) states of massless and massive fermions can exist at both orbifold fixed points. Closer look however indicates that orbifold boundary conditions act to suppress at least half of bound KK modes, while periodic boundary conditions tend to drive the high-lying modes to the conventional structure. By investigating the scattering of fermions on branes, we analytically compute masses and wavefunctions of KK spectra in the presence of these boundary conditions up to one-loop level. Implication of KK-number non-conservation couplings on the Coulomb potential is also examined.
García-Jiménez, I.; Novales-Sánchez, H.; Toscano, J. J.
2016-05-01
One-loop Standard Model observables produced by virtual heavy Kaluza-Klein fields play a prominent role in the minimal model of universal extra dimensions. Motivated by this aspect, we integrate out all the Kaluza-Klein heavy modes coming from the Yang-Mills theory set on a spacetime with an arbitrary number, n , of compact extra dimensions. After fixing the gauge with respect to the Kaluza-Klein heavy gauge modes in a covariant manner, we calculate a gauge-independent effective Lagrangian expansion containing multiple Kaluza-Klein sums that entail a bad divergent behavior. We use the Epstein-zeta function to regularize and characterize discrete divergences within such multiple sums, and then we discuss the interplay between the number of extra dimensions and the degree of accuracy of effective Lagrangians to generate or not divergent terms of discrete origin. We find that nonrenormalizable terms with mass dimension k are finite as long as k >4 +n . Multiple Kaluza-Klein sums of nondecoupling logarithmic terms, not treatable by Epstein-zeta regularization, are produced by four-dimensional momentum integration. On the grounds of standard renormalization, we argue that such effects are unobservable.
García-Jiménez, I; Toscano, J J
2016-01-01
One-loop Standard Model observables produced by virtual heavy Kaluza-Klein fields play a prominent role in the minimal model of universal extra dimensions. Motivated by this aspect, we integrate out all the Kaluza-Klein heavy modes coming from the Yang-Mills theory set on a spacetime with an arbitrary number, $n$, of compact extra dimensions. After fixing the gauge with respect to the Kaluza-Klein heavy gauge modes in a covariant manner, we calculate a gauge independent effective Lagrangian expansion containing multiple Kaluza-Klein sums that entail a bad divergent behavior. We use the Epstein-zeta function to regularize and characterize discrete divergences within such multiple sums, and then we discuss the interplay between the number of extra dimensions and the degree of accuracy of effective Lagrangians to generate or not divergent terms of discrete origin. We find that nonrenormalizable terms with mass dimension $k$ are finite as long as $k>4+n$. Multiple Kaluza-Klein sums of nondecoupling logarithmic te...
Liko, T
2005-01-01
The field equations for gravitation and electromagnetism with sources in four dimensions can be interpreted as arising from the vacuum Einstein equations in five dimensions. Gauge invariance of the electromagnetic potentials leads to a ``generalized'' electromagnetic field tensor. We use the action principle to derive the equations of motion for free electromagnetic fields in flat spacetime, and isolate an effective electromagnetic current with a source that is purely higher-dimensional in origin. This current provides, at least in principle, a means of detecting extra dimensions experimentally.
Galactic entropy in extended Kaluza-Klein cosmology
Yanar, Hilmi; Salti, Mustafa; Aydogdu, Oktay; Acikgoz, Irfan; Yasar, Erol
2016-02-01
We use a Kaluza-Klein model with variable cosmological and gravitational terms to discuss the nature of galactic entropy function. For this purpose, we assume a universe filled with dark fluid and consider five-dimensional (5D) field equations using the Gamma law equation. We mainly discuss the validity of the first and generalized second laws of galactic thermodynamics for viable Kaluza-Klein models.
Dynamics of localized Kaluza-Klein black holes in a collapsing universe
Kastor, David; Traschen, Jennie
2011-01-01
The Clayton Antitrust Act of 1914 prohibits corporate mergers that would result in certain highly undesired end states. We study an exact solution of the Einstein equations describing localized, charged Kaluza-Klein black holes in a collapsing deSitter universe and seek to demonstrate that a similar effect holds, preventing a potentially catastrophic black hole merger. As the collapse proceeds, it is natural to expect that the black hole undergoes a topological transition, wrapping around the shrinking compact dimension to merge with itself and form a black string. However, the putative uniform charged black string end state is singular and such a transition would violate (a reasonable notion of) cosmic censorship. We present analytic and numerical evidence that strongly suggests the absence of such a transition. Based on this evidence, we expect that the Kaluza-Klein black hole horizon stays localized, despite the increasingly constraining size of the compact dimension. On the other hand, the deSitter horizo...
Harrison transformation and charged black objects in Kaluza-Klein theory
Kleihaus, Burkhard; Kunz, Jutta; Radu, Eugen; Stelea, Cristian
2009-09-01
We generate charged black brane solutions in D-dimensions in a theory of gravity coupled to a dilaton and an antisymmetric form, by using a Harrison-type transformation. The seed vacuum solutions that we use correspond to uplifted Kaluza-Klein black strings and black holes in (D-p)-dimensions. A generalization of the Marolf-Mann quasilocal formalism to the Kaluza-Klein theory is also presented, the global charges of the black objects being computed in this way. We argue that the thermodynamics of the charged solutions can be derived from that of the vacuum configurations. Our results show that all charged Kaluza-Klein solutions constructed by means of Harrison transformations are thermodynamically unstable in a grand canonical ensemble. The general formalism is applied to the case of nonuniform black strings and caged black hole solutions in D = 5,6 Einstein-Maxwell-dilaton gravity, whose geometrical properties and thermodynamics are discussed. We argue that the topology changing transition scenario, which was previously proposed in the vacuum case, also holds in this case. Spinning generalizations of the charged black strings are constructed in six dimensions in the slowly rotating limit. We find that the gyromagnetic ratio of these solutions possesses a nontrivial dependence on the nonuniformity parameter.
Phenomenology of neutrino physics in the Kaluza-Klein theories of low scale gravity
Ioannisian, A N
2001-01-01
We discuss the phenomenological consequences of theories which describe sterile neutrinos in large extra dimensions. We show that the Kaluza-Klein tower of the singlet neutrinos, albeit tiny individual contribution in electroweak processes, act cumulatively, giving rise to non-universality of the weak interactions of the light neutrinos and to flavour-violating radiative processes. Owing to these non-decoupling effects of th Kaluza--Klein neutrinos, we derive strong constraints on the parameters of the theory that originates from the non-observation of flavour-violating and universality-breaking phenomena. In this theory we propose a four-neutrino model which can reconcile the existing data coming from underground experiments in terms of neutrino oscillations, together with the hint from the LSND experiment and a possible neutrino contribution to the hot dark matter of the Universe.
Kaluza-Klein gravitons at LHC2
Dillon, Barry M.; Sanz, Veronica
2017-08-01
In this work we study constraints from new searches for heavy particles at the LHC on the allowed masses and couplings of a Kaluza-Klein (KK) graviton in a holographic composite Higgs model. Keeping new electroweak states heavy such that electroweak precision tests are satisfied, we control the mass of the lightest KK graviton using a brane kinetic term. With this we study KK graviton masses from 0.5-3 TeV. In our analysis we also employ little Randall-Sundrum (RS) models, characterized by a lower UV scale in the five-dimensional model which in turn implies modified couplings to massless bulk fields. Viewing this scenario as a strongly coupled four-dimensional theory with a composite Higgs boson, the KK graviton is interpreted as a composite spin-2 state and the varying UV scale corresponds to a varying intermediate scale between the cutoff of the low-energy effective theory and the Planck scale. We find that KK gravitons with masses in the range [500, 3000] GeV are compatible with current collider constraints, where the most promising channels for detecting these states are the diphoton and Z Z channels. A detection is more likely in the little RS models, in which the dual gauge theory has a larger number of colors than in traditional RS models.
Harrison transformation and charged black objects in Kaluza-Klein theory
Kleihaus, Burkhard; Radu, Eugen; Stelea, Cristian
2009-01-01
We generate charged black brane solutions in $D-$dimensions in a theory of gravity coupled to a dilaton and an antisymmetric form, by using a Harrison-type transformation. The seed vacuum solutions that we use correspond to uplifted Kaluza-Klein black strings and black holes in $(D-p)$-dimensions. A generalization of the Marolf-Mann quasilocal formalism to the Kaluza-Klein theory is also presented, the global charges of the black objects being computed in this way. We argue that the thermodynamics of the charged solutions can be derived from that of the vacuum configurations. Our results show that all charged Kaluza-Klein solutions constructed by means of Harrison transformations are thermodynamically unstable in a grand canonical ensemble. The general formalism is applied to the case of nonuniform black strings and caged black hole solutions in $D=5, 6$ Einstein-Maxwell-dilaton gravity, whose geometrical properties and thermodynamics are discussed. We argue that the topology changing transition scenario, whi...
Klein-Gordon oscillator in Kaluza-Klein theory
Carvalho, Josevi; Carvalho, Alexandre M. de M.; Cavalcante, Everton; Furtado, Claudio
2016-07-01
In this contribution we study the Klein-Gordon oscillator on the curved background within the Kaluza-Klein theory. The problem of the interaction between particles coupled harmonically with topological defects in Kaluza-Klein theory is studied. We consider a series of topological defects, then we treat the Klein-Gordon oscillator coupled to this background, and we find the energy levels and corresponding eigenfunctions in these cases. We show that the energy levels depend on the global parameters characterizing these spacetimes. We also investigate a quantum particle described by the Klein-Gordon oscillator interacting with a cosmic dislocation in Som-Raychaudhuri spacetime in the presence of homogeneous magnetic field in a Kaluza-Klein theory. In this case, the energy spectrum is determined, and we observe that these energy levels represent themselves as the sum of the terms related with Aharonov-Bohm flux and of the parameter associated to the rotation of the spacetime.
Finite temperature Casimir effect in Kaluza-Klein spacetime
Energy Technology Data Exchange (ETDEWEB)
Teo, L.P. [Faculty of Information Technology, Multimedia University, Jalan Multimedia, Cyberjaya, 63100 Selangor Darul Ehsan (Malaysia)], E-mail: lpteo@mmu.edu.my
2009-10-01
In this article, we consider the finite temperature Casimir effect in Kaluza-Klein spacetime due the vacuum fluctuation of massless scalar field with Dirichlet boundary conditions. We consider the general case where the extra dimensions (internal space) can be any compact connected manifold or orbifold without boundaries. Using piston analysis, we show that the Casimir force is always attractive at any temperature, regardless of the geometry of the internal space. Moreover, the magnitude of the Casimir force increases as the size of the internal space increases and it reduces to the Casimir force in (3+1)-dimensional Minkowski spacetime when the size of the internal space shrinks to zero. In the other extreme where the internal space is large, the Casimir force can increase beyond all bound. Asymptotic behaviors of the Casimir force in the low and high temperature regimes are derived and it is observed that the magnitude of the Casimir force grows linearly with temperature in the high temperature regime.
Direct Detection of Kaluza-Klein Particles in Neutrino Telescopes
Albuquerque, Ivone F M; Krenke, Christopher A; Nosratpour, Baran
2008-01-01
In theories with universal extra dimensions (UEDs), all standard model fields propagate in the bulk and the lightest state of the first Kaluza-Klein (KK) level can be made stable by imposing a Z2 parity. We consider a framework where the lightest KK particle (LKP) is a neutral, extremely weakly interacting particle such as the first KK excitation of the graviton, while the next-to-lightest KK particle (NLKP) is the first KK mode of a charged right-handed lepton. In such a scenario, due to its very small couplings to the LKP, the NLKP is long-lived. We investigate the production of these particles from the interaction of high energy neutrinos with nucleons in the Earth, and determine the rate of NLKP events in neutrino telescopes. Using the Waxman-Bahcall limit for the neutrino flux, we find that the rate can be as large as a few hundreds events a year for realistic values of the NLKP mass.
Boosted Black Holes on Kaluza-Klein Bubbles
Iguchi, Hideo; Tomizawa, Shinya
2007-01-01
We construct an exact stationary solution of black hole -- bubble sequence in the five dimensional Kaluza-Klein theory by using solitonic solution generating techniques. The solution describes two boosted black holes with topology S^3 on a Kaluza-Klein bubble and has a linear momentum component in the compactified direction. The ADM mass and the linear momentum depend on the two boosted velocity parameters of black holes. In the effective four dimensional theory, the solution has an electric charge which is proportional to the linear momentum. The solution includes the static solution found by Elvang and Horowitz and a limit of single boosted black string.
Rotating Black Holes on Kaluza-Klein Bubbles
Tomizawa, S; Mishima, T; Iguchi, Hideo; Mishima, Takashi; Tomizawa, Shinya
2007-01-01
Using the solitonic solution generating techniques, we generate a new exact solution which describes a pair of rotating black holes on a Kaluza-Klein bubble as a vacuum solution in the five-dimensional Kaluza-Klein theory. We also investigate the properties of this solution. Two black holes with topology S^3 are rotating along the same direction and the bubble plays a role in holding two black holes. In static case, it coincides with the solution found by Elvang and Horowitz.
Kaluza--Klein Cosmology from five-dimensional Lovelock--Cartan Theory
Castillo-Felisola, Oscar; del Pino, Simón; Ramírez, Francisca
2016-01-01
We study the Kaluza-Klein dimensional reduction of the Lovelock-Cartan theory in five-dimensional spacetime, with a compact dimension of $S^1$ topology. We find cosmological solutions of the Friedmann-Robertson-Walker class in the reduced spacetime. The torsion and the fields arising from the dimensional reduction induce a nonvanishing energy-momentum tensor in four dimensions. We find solutions describing expanding, contracting and bouncing universes. The model shows a dynamical compactification of the extra dimension in some regions of the parameter space.
Kaluza-Klein monopoles and gauged sigma-models
Bergshoeff, E; Janssen, B; Ortin, T; Alvarez-Gaumé, L.
1997-01-01
We propose an effective action for the eleven-dimensional (bosonic) Kaluza-Klein monopole solution. The construction of the action requires that the background fields admit an Abelian isometry group. The corresponding sigma-model is gauged with respect to this isometry. The gauged sigma-model is the
Kaluza-Klein Monopoles and Gauged Sigma Models
Bergshoeff, E.A.
1998-01-01
We review some aspects of branes. In particular, we discuss the worldvolume theory describing the dynamics of the Kaluza-Klein monopole which turns out to be a gauged sigma model. We also briefly review some recent applications of gauged sigma models to the worldvolume description of massive branes,
Fermion dynamics in the Kaluza-Klein monopole geometry
Bais, F.A.; Batenburg, P.
1984-01-01
The behaviour of charged particles in the Kaluza-Klein monopole geometry is studied. A discussion of the five-dimensional geodesics is followed by an analysis of the corresponding Dirac equation. A main observation is that a charged particle cannot reach the core of the pole, in contrast with the co
Tunneling of Dirac Particles from Kaluza-Klein Black Hole
Institute of Scientific and Technical Information of China (English)
ZENG Xiao-Xiong; LI Qiang
2009-01-01
Applying the fermions tunneling method, proposed by Kerner and Mann recently, we discuss the tunneling characteristics of Dirac particles from the stationary Kaluza-Klein black hole. To choose Gamma matrix conveniently and avoid the ergosphere dragging effect, we perform it in the dragging coordinate frame. The result shows that Hawking temperature in this case also can be reproduced by the general Dirac equation.
Kaluza-Klein monopole and 5-brane effective actions
Eyras, E; Lozano, Y
2000-01-01
We review the construction of the Kaluza-Klein monopole of the Type IIA theory in the most general case of a massive background, as well as its relation via T-duality with the Type IIB NS-5-brane. This last effective action is shown to be related by S-duality to the D5-brane effective action. [GRAPH
Kaluza-Klein theory and Aharonov-Bohm effect
Energy Technology Data Exchange (ETDEWEB)
Ferrari, J.A.; Griego, J.
1986-11-11
Recently Bocchieri et al. have shown that the Aharonov-Bohm effect appears to be in contradiction with the laws of quantum mechanics. The present paper provided an alternative (non-quantum-mechanical) explanation of the Aharonov-Bohm effect by using only De Broglie's undulatory hypothesis and the five-dimensional Kaluza-Klein theory.
Fermion dynamics in the Kaluza-Klein monopole geometry
Bais, F.A.; Batenburg, P.
1984-01-01
The behaviour of charged particles in the Kaluza-Klein monopole geometry is studied. A discussion of the five-dimensional geodesics is followed by an analysis of the corresponding Dirac equation. A main observation is that a charged particle cannot reach the core of the pole, in contrast with the co
Hawking Radiation via Damour-Ruffini Method in Squashed Charged Rotating Kaluza-Klein Black Holes
Hu, Ji-Wan; Wu, Jing-He; Liu, Xian-Ming
2017-02-01
Using the Damour-Ruffini method, Hawking radiation of charged particles from squashed charged rotating five-dimensional Kaluza-Klein black holes is investigated extensively. Under the generalized tortoise coordinate transformation, Hawking temperature of the black holes is calculated by using charged scalar particles and Dirac fermions respectively. We find that the obtained Hawking temperature for charged Dirac fermions is the same as for charged scalar particles. What's more, the spectrum of Hawking radiation contains the information of the size of the extra dimension, which could provide insight for further investigation of large extra dimensions in the future.
Massive Kaluza-Klein theories and their spontaneously broken symmetries
Energy Technology Data Exchange (ETDEWEB)
Hohm, O.
2006-07-15
In this thesis we investigate the effective actions for massive Kaluza-Klein states, focusing on the massive modes of spin-3/2 and spin-2 fields. To this end we determine the spontaneously broken gauge symmetries associated to these 'higher-spin' states and construct the unbroken phase of the Kaluza-Klein theory. We show that for the particular background AdS{sub 3} x S{sup 3} x S{sup 3} a consistent coupling of the first massive spin-3/2 multiplet requires an enhancement of local supersymmetry, which in turn will be partially broken in the Kaluza-Klein vacuum. The corresponding action is constructed as a gauged maximal supergravity in D=3. Subsequently, the symmetries underlying an infinite tower of massive spin-2 states are analyzed in case of a Kaluza-Klein compactification of four-dimensional gravity to D=3. It is shown that the resulting gravity-spin-2 theory is given by a Chern-Simons action of an affine algebra and also allows a geometrical interpretation in terms of 'algebra-valued' differential geometry. The global symmetry group is determined, which contains an affine extension of the Ehlers group. We show that the broken phase can in turn be constructed via gauging a certain subgroup of the global symmetry group. Finally, deformations of the Kaluza-Klein theory on AdS{sub 3} x S{sup 3} x S{sup 3} and the corresponding symmetry breakings are analyzed as possible applications for the AdS/CFT correspondence. (Orig.)
Improved upper bounds on Kaluza-Klein gravity with current Solar System experiments and observations
Deng, Xue-Mei
2015-01-01
As an extension of previous works on classical tests of Kaluza-Klein (KK) gravity and as an attempt to find more stringent constraints on this theory, its effects on physical experiments and astronomical observations conducted in the Solar System are studied. We investigate the gravitational time delay at inferior conjunction caused by KK gravity, and use new Solar System ephemerides and the observation of \\textit{Cassini} to strengthen constraints on KK gravity by up to two orders of magnitude. These improved upper bounds mean that the fifth-dimensional space in the soliton case is a very flat extra dimension in the Solar System, even in the vicinity of the Sun.
Improved upper bounds on Kaluza-Klein gravity with current Solar System experiments and observations
Energy Technology Data Exchange (ETDEWEB)
Deng, Xue-Mei [Chinese Academy of Sciences, Purple Mountain Observatory, Nanjing (China); Xie, Yi [Nanjing University, School of Astronomy and Space Science, Nanjing (China); Shanghai Key Laboratory of Space Navigation and Position Techniques, Shanghai (China); Nanjing University, Ministry of Education, Key Laboratory of Modern Astronomy and Astrophysics, Nanjing (China)
2015-11-15
As an extension of previous works on classical tests of Kaluza-Klein (KK) gravity and as an attempt to find more stringent constraints on this theory, its effects on physical experiments and astronomical observations conducted in the Solar System are studied. We investigate the gravitational time delay at inferior conjunction caused by KK gravity, and use new Solar System ephemerides and the observation of Cassini to strengthen constraints on KK gravity by up to two orders of magnitude. These improved upper bounds mean that the fifth-dimensional space in the soliton case is a very flat extra dimension in the Solar System, even in the vicinity of the Sun. (orig.)
Kaluza-Klein Reduction of a Quadratic Curvature Model
Baskal, S
2010-01-01
Palatini variational principle is implemented on a five dimensional quadratic curvature gravity model, rendering two sets of equations which can be interpreted as the field equations and the stress-energy tensor. Unification of gravity with electromagnetism and the scalar dilaton field is achieved through the Kaluza-Klein dimensional reduction mechanism. The reduced curvature invariant, field equations and the stress-energy tensor in four dimensional spacetime are obtained. The structure of the interactions among the constituent fields is exhibited in detail. It is shown that the Lorentz force naturally emerges from the reduced field equations and the equations of the standard Kaluza-Klein theory is demonstrated to be intrinsically contained in this model.
Conformal anomaly and compactification of Kaluza--Klein models
Energy Technology Data Exchange (ETDEWEB)
Vasilevich, D.V.; Shtykov, N.N.
1988-10-01
An O (d)-invariant regularization of d-dimensional Kaluza--Klein models with scalar and fermion fields is proposed. The regularization preserves the power divergences and does not give inverse powers of the cutoff parameter in the conformal anomaly. The one-loop corrections to the trace of the energy--momentum tensor are calculated for internal spaces S/sup 2/, S/sup 4/, and S/sup 6/.
Newton-Cartan, Galileo-Maxwell and Kaluza-Klein
Bleeken, Dieter Van den
2015-01-01
We study Kaluza-Klein reduction in Newton-Cartan gravity. In particular we show that dimensional reduction and the nonrelativistic limit commute. The resulting theory contains Galilean electromagnetism and a nonrelativistic scalar. It provides the first example of back-reacted couplings of scalar and vector matter to Newton-Cartan gravity. This back-reaction is interesting as it sources the spatial Ricci curvature, providing an example where nonrelativistic gravity is more than just a Newtonian potential.
Towards Kaluza-Klein Dark Matter on nilmanifolds
Andriot, David; Cacciapaglia, Giacomo; Deandrea, Aldo; Deutschmann, Nicolas; Tsimpis, Dimitrios
2016-06-01
We present a first study of the field spectrum on a class of negatively-curved compact spaces: nilmanifolds or twisted tori. This is a case where analytical results can be obtained, allowing to check numerical methods. We focus on the Kaluza-Klein expansion of a scalar field. The results are then applied to a toy model where a natural Dark Matter candidate arises as a stable massive state of the bulk scalar.
A Dark Energy Model in Kaluza-Klein Cosmology
Mukhopadhyay, Utpal; Chakraborty, Ipsita; Ray, Saibal; Usmani, A. A.
2016-01-01
We study a dynamic Λ model with varying gravitational constant G under the Kaluza-Klein cosmology. Physical features and the limitations of the present model have been explored and discussed. Solutions are found mostly in accordance with the observed features of the accelerating universe. Interestingly, signature flipping of the deceleration parameter is noticed and the present age of the Universe is also attainable under certain stringent conditions. We find that the time variation of gravitational constant is not permitted without vintage Λ.
A Dark Energy Model in Kaluza-Klein Cosmology
Mukhopadhyay, Utpal; Ray, Saibal; Usmani, A A
2014-01-01
We study a dynamic $\\Lambda$ model with varying gravitational constant $G$ under the Kaluza-Klein cosmology. Physical features and the limitations of the present model have been explored and discussed. Solutions are found mostly in accordance with the observed features of the accelerating universe. Interestingly, signature flipping of the deceleration parameter is noticed and the present age of the Universe is also attainable under certain stringent conditions. We find that the time variation of gravitational constant is not permitted without vintage $\\Lambda$.
Constraints on cosmic superstrings from Kaluza-Klein emission.
Dufaux, Jean-François
2012-07-01
Cosmic superstrings interact generically with a tower of light and/or strongly coupled Kaluza-Klein (KK) modes associated with the geometry of the internal space. We study the production of KK particles by cosmic superstring loops, and show that it is constrained by big bang nucleosynthesis. We study the resulting constraints in the parameter space of the underlying string theory model and highlight their complementarity with the regions that can be probed by current and upcoming gravitational wave experiments.
Newton-Cartan, Galileo-Maxwell and Kaluza-Klein
Van den Bleeken, Dieter; Yunus, Çağin
2016-07-01
We study Kaluza-Klein reduction in Newton-Cartan gravity. In particular we show that dimensional reduction and the nonrelativistic limit commute. The resulting theory contains Galilean electromagnetism and a nonrelativistic scalar. It provides the first example of back-reacted couplings of scalar and vector matter to Newton-Cartan gravity. This back-reaction is interesting as it sources the spatial Ricci curvature, providing an example where nonrelativistic gravity is more than just a Newtonian potential.
Gauged diffeomorphisms and hidden symmetries in Kaluza-Klein theories
Energy Technology Data Exchange (ETDEWEB)
Hohm, Olaf [Spinoza Institute and Institute for Theoretical Physics, Leuvenlaan 4, 3584 CE Utrecht (Netherlands)
2007-06-07
We analyse the symmetries that are realized on the massive Kaluza-Klein modes in generic D-dimensional backgrounds with three non-compact directions. For this, we construct the unbroken phase given by the decompactification limit, in which the higher Kaluza-Klein modes are massless. The latter admits an infinite-dimensional extension of the three-dimensional diffeomorphism group as local symmetry and, moreover, a current algebra associated with SL(D-2,R) together with the diffeomorphism algebra of the internal manifold as global symmetries. It is shown that the 'broken phase' can be reconstructed by gauging a certain subgroup of the global symmetries. This deforms the three-dimensional diffeomorphisms to a gauged version, and it is shown that they can be governed by a Chern-Simons theory, which unifies the spin-2 modes with the Kaluza-Klein vectors. This provides a reformulation of D-dimensional Einstein gravity, in which the physical degrees of freedom are described by the scalars of a gauged nonlinear {sigma}-model based on SL(D-2,R)/SO(D-2), while the metric appears in a purely topological Chern-Simons form.
Dynamics of localized Kaluza-Klein black holes in a collapsing universe
Kastor, David; Sorbo, Lorenzo; Traschen, Jennie
2012-03-01
The Clayton Antitrust Act of 1914 prohibits corporate mergers that would result in certain highly undesired end states. We study an exact solution of the Einstein equations describing localized, charged Kaluza-Klein black holes in a collapsing de Sitter universe and seek to demonstrate that a similar effect holds, preventing a potentially catastrophic black hole merger. As the collapse proceeds, it is natural to expect that the black hole undergoes a topological transition, wrapping around the shrinking compact dimension to merge with itself and form a black string. However, the putative uniform charged black string end state is singular and such a transition would violate (a reasonable notion of) cosmic censorship. We present analytic and numerical evidence that strongly suggests the absence of such a transition. Based on this evidence, we expect that the Kaluza-Klein black hole horizon stays localized, despite the increasingly constraining size of the compact dimension. On the other hand, the de Sitter horizon does change between spherical and cylindrical topologies in a simple way.
Kaluza-Klein graviton phenomenology for warped compactifications, and the 750 GeV diphoton excess
Giddings, Steven B.; Zhang, Hao
2016-06-01
A generic prediction of scenarios with extra dimensions accessible in TeV-scale collisions is the existence of Kaluza-Klein excitations of the graviton. For a broad class of strongly warped scenarios one expects to initially find an isolated resonance, whose phenomenology in the simplest cases is described by a simplified model with two parameters, its mass, and a constant Λ with units of mass parametrizing its coupling to the Standard Model stress tensor. These parameters are in turn determined by the geometrical configuration of the warped compactification. We explore the possibility that the 750 GeV excess recently seen in 13 TeV data at ATLAS and CMS could be such a warped Kaluza-Klein graviton, and find a best-fit value Λ ≈60 TeV . We find that while there is some tension between this interpretation and data from 8 TeV and from the dilepton channel at 13 TeV, it is not strongly excluded. However, in the simplest scenarios of this kind, such a signal should soon become apparent in both diphoton and dilepton channels.
Kaluza-Klein graviton phenomenology for warped compactifications, and the 750 GeV diphoton excess
Giddings, Steven B
2016-01-01
A generic prediction of scenarios with extra dimensions accessible in TeV-scale collisions is the existence of Kaluza-Klein excitations of the graviton. For a broad class of strongly-warped scenarios one expects to initially find an isolated resonance, whose phenomenology in the simplest cases is described by a simplified model with two parameters, its mass, and a constant $\\Lambda$ with units of mass parameterizing its coupling to the Standard Model stress tensor. These parameters are in turn determined by the geometrical configuration of the warped compactification. We explore the possibility that the 750 GeV excess recently seen in 13 TeV data at ATLAS and CMS could be such a warped Kaluza-Klein graviton, and find a best-fit value $\\Lambda\\approx 60$ TeV. We find that while there is some tension between this interpretation and data from 8 TeV and from the dilepton channel at 13 TeV, it is not strongly excluded. However, in the simplest scenarios of this kind, such a signal should soon become apparent in bo...
Schwarzschild-like exteriors for stars in Kaluza-Klein gravity
de Leon, J Ponce
2010-01-01
In this work we examine the effective four-dimensional world that emanates from a general class of static spherical Ricci-flat solutions in Kaluza-Klein gravity in $D$-dimensions. By means of dimensional reduction we obtain a family of asymptotically flat Schwarzschild-like metrics for which all the components of the Ricci tensor, except for $R_{11}$, are zero. Although the reduced spacetime is not empty, it is similar to vacuum in the sense that the effective matter satisfies an equation of state which is the generalization of $(\\rho + 3p) = 0$ for "nongravitating matter" in 4D. In Kaluza-Klein gravity these Schwarzschild-like metrics describe the exterior of a spherical star without rotation. In this framework, we generalize the well-known Buchdahl's theorem for perfect fluid spheres whose mass density does not increase outward. Without any additional assumptions, we develop the most general expression for the compactness limit of a star. We provide some numerical values for it, which in principle are obser...
Energy Technology Data Exchange (ETDEWEB)
Rizzo, T.G.
2000-01-24
The authors review the capability of e{sup +}e{sup {minus}} and e{sup {minus}}e{sup {minus}} colliders to detect the virtual exchange of Kaluza-Klein towers of gravitons within the large extra dimension scenario of Arkani-Hamed, Dimopoulos and Dvali and in the localized gravity model of Randall and Sundrum with non-factorizable geometry.
Kaluza-Klein Magnetized Cylindrical Wormhole
Hashemi, S Sedigheh
2015-01-01
A new exact vacuum solution in five dimensions, which describes a magnetized cylindrical wormhole in $3+1$ dimensions is presented. The magnetic field lines are stretched along the wormhole throat and are concentrated near to it. We study the motion of neutral and charged test particles under the influence of the magnetized wormhole. The effective potential for a neutral test particle around and across the magnetized wormhole has a repulsive character. The total magnetic flux on either side of the wormhole is obtained. We present analytic expressions which show regions in which the null energy condition is violated.
Kaluza-Klein Theories Without Truncation
Becker, Katrin; Robbins, Daniel
2014-01-01
In this note we present a closed expression for the space-time effective action for all bosonic fields (massless and massive) obtained from the compactification of gravity or supergravity theories (such as type II or eleven-dimensional supergravities) from $D$ to $d$ space-time dimensions.
Alfaro, J; Labraña, P; Alfaro, Jorge; Andrianov, Alexander; Labraña, Pedro
2003-01-01
In this paper we study a reduced QCD model in $(1+1)$ dimensions obtained from QCD in 4D by compactifying two spatial dimensions. We work out this model in the large $N_c$ limit and using light cone gauge. This system is found to induce a dynamical mass for transverse gluons -- adjoint scalars in $QCD_2$, and to undergo a spontaneous chiral symmetry breaking with the full quark propagators yielding non-tachyonic, dynamical quark masses, even in the chiral limit. We study quark-antiquark bound states which can be classified in this model by their properties under Lorentz transformations in 4D. The scalar and pseudoscalar sectors of the theory are examined revealing a massless ground state for pseudoscalars, different from the so called 't Hooft pion solution, and a massive spectrum for scalars.
Wormhole in 5D Kaluza-Klein cosmology
Biswas, Gargi; Modak, B.
2017-03-01
We present wormhole as a solution of Euclidean field equations as well as the solution of the Wheeler-deWitt (WD) equation satisfying Hawking-Page wormhole boundary conditions in (4 + 1)-dimensional Kaluza-Klein cosmology. The wormholes are considered in the cases of pure gravity, minimally coupled scalar (imaginary) field and with a positive cosmological constant assuming dynamical extra-dimensional space. In above cases, wormholes are allowed both from Euclidean field equations and WD equation. The dimensional reduction is possible.
Kaluza-Klein Aspects of Noncommutative Geometry
Madore, J
2015-01-01
Using some elementary methods from noncommutative geometry a structure is given to a point of space-time which is different from and simpler than that which would come from extra dimensions. The structure is described by a supplementary factor in the algebra which in noncommutative geometry replaces the algebra of functions. Using different examples of algebras it is shown that the extra structure can be used to describe spin or isospin.
Compact stars in Kaluza -Klein World
Gábor Barnaföldi, Gergely; Lévai, Péter; Lukács, Béla
2010-03-01
Unification and geometrization of interactions has been extensively studied during the XX. century. In this short contribution we investigated the possible effect of an extra compactified dimension (alias hypercharge) on a flavor dependent gravitational potential, proposed by Fischbach et al.. We estimated the deviation from the 3 + 1 dimensional scheme and found that, although the deviation is moderate, for celestial compact object it may be higher by orders of magnitude than in terrestrial laboratory measurements.
A T-duality approach to the gravitational wave and the Kaluza-Klein monopole
Janssen, B
1999-01-01
We present a world volume action for the gravitational wave and the (bosonic) N = 1 Heterotic Kaluza-Klein monopole solution. In the construction of the action we make use of the fact that the wave and the Kaluza-Klein monopole are T-dual to the fundamental string and the solitonic five-brane, and w
On Hamiltonians with position-dependent mass from Kaluza-Klein compactifications
Ballesteros, Ángel; Gutiérrez-Sagredo, Iván; Naranjo, Pedro
2017-02-01
In a recent paper (Morris (2015) [1]), an inhomogeneous compactification of the extra dimension of a five-dimensional Kaluza-Klein metric has been shown to generate a position-dependent mass (PDM) in the corresponding four-dimensional system. As an application of this dimensional reduction mechanism, a specific static dilatonic scalar field has been connected with a PDM Lagrangian describing a well-known nonlinear PDM oscillator. Here we present more instances of this construction that lead to PDM systems with radial symmetry, and the properties of their corresponding inhomogeneous extra dimensions are compared with the ones in the nonlinear oscillator model. Moreover, it is also shown how the compactification introduced in this type of models can alternatively be interpreted as a novel mechanism for the dynamical generation of curvature.
On Hamiltonians with position-dependent mass from Kaluza-Klein compactifications
Ballesteros, Ángel; Naranjo, Pedro
2016-01-01
In a recent paper [1], an inhomogeneous compactification of the extra dimension of a five dimensional Kaluza-Klein metric has been shown to generate a position-dependent mass in the corresponding four dimensional system. As an application of this dimensional reduction mechanism, a specific static dilatonic scalar field has been connected with a PDM Lagrangian describing a well-known nonlinear PDM oscillator. Here we present two more instances of this construction that lead to two distinguished superintegrable PDM systems: the so-called Darboux III and Taub-NUT Hamiltonians, and the properties of the inhomogeneous extra dimensions connected with them are compared with the ones in the nonlinear oscillator model. It is worth stressing that the Darboux III and Taub-NUT define exactly solvable quantum models, whose spectrum and eigenfuctions are explicitly known. Finally, it is shown that the compactification introduced in [1] can be alternatively interpreted as a mechanism for the dynamical generation of curvatur...
Proper time and conformal problem in Kaluza-Klein theory
Minguzzi, E
2015-01-01
In the traditional Kaluza-Klein theory, the cylinder condition and the constancy of the extra-dimensional radius (scalar field) imply that timelike geodesics on the 5-dimensional bundle project to solutions of the Lorentz force equation on spacetime. This property is lost for non constant scalar fields, in fact there appear new terms that have been interpreted mainly as new forces or as due to a variable inertial mass and/or charge. Here we prove that the additional terms can be removed if we assume that charged particles are coupled with the same spacetime conformal structure of neutral particles but through a different conformal factor. As a consequence, in Kaluza-Klein theory the proper time of the charged particle might depend on the charge-to-mass ratio and the scalar field. Then we show that the compatibility between the equation of the projected geodesic and the classical limit of the Klein-Gordon equation fixes unambiguously the conformal factor of the coupling metric solving the `conformal ambiguity ...
Scalar dark matter in an extra dimension inspired model
Lineros, Roberto; Pereira dos Santos, Fabio
2016-05-01
In this work we consider a singlet scalar propagating in a flat large extra dimension. The first Kaluza-Klein mode associated to this singlet scalar will be a viable dark matter candidate. The tower of new particles enriches the calculation of the relic density due effect of coannihilation. For large mass splitting, the model converges to the predictions of the singlet dark matter model. For nearly degenerate mass spectrum, coannihilations increase the cross-sections used for direct and indirect dark matter searches. We investigate the impact of the Kaluza-Klein tower associated to singlet scalar for indirect and direct detection of dark matter.
Braneworld effective action An alternative to Kaluza-Klein reduction
Barvinsky, A O; Rathke, A; Kiefer, C; Barvinsky, Andrei; Kamenshchik, Alexander; Rathke, Andreas; Kiefer, Claus
2003-01-01
We construct the braneworld effective action in the two-brane Randall-Sundrum model in a setup alternative to Kaluza-Klein reduction: The action is written as a functional of the two metric and radion fields on the branes. In the low-energy spectrum of the model we find two - one massless and one massive - graviton modes, the mass of the massive mode diverging in the limit of merging branes. Our results confirm a recently proposed model of braneworld inflation with diverging branes. They also suggest the possibility of a new mechanism for a repulsive interbrane potential which can underlie the model of colliding "thick" branes in the Big Crunch/Big Bang transitions in cosmology. Mixing of the obtained massless and massive modes can be interpreted as radion-induced graviton oscillations potentially interesting for gravitational wave astronomy.
Kaluza-Klein reduction of relativistic fluids and their gravity duals
Di Dato, Adriana
2013-01-01
We study the hydrodynamics of relativistic fluids with several conserved global charges (i.e., several species of particles) by performing a Kaluza-Klein dimensional reduction of a neutral fluid on a N-torus. Via fluid/gravity correspondence, this allows us to describe the long-wavelength dynamics of black branes with several Kaluza-Klein charges. We obtain the equation of state and transport coefficients of the charged fluid directly from those of the higher-dimensional neutral fluid. We specialize these results for the fluids dual to Kaluza-Klein black branes.
Dynamical fermion masses under the influence of Kaluza-Klein fermions in extradimensions
Abe, Hiroyuki; Miguchi, Hironori; Muta, Taizo
2000-01-01
The dynamical fermion mass generation in the 4-dimensional brane is discussed in a model with 5-dimensional Kaluza-Klein fermions in interaction with 4-dimensional fermions. It is found that the dynamical fermion masses are generated beyond the critical radius of the compactified extra dimensional space and may be made small compared with masses of the Kaluza-Klein modes. 04.50.th, 04.60.-m, 11.15.Pg, 11.30.Qc
Institute of Scientific and Technical Information of China (English)
Li Hui-Ling
2011-01-01
This paper is devoted to the investigation the fermion tunneling radiation of squashed black holes in the Godel universe and charged Kaluza-Klein space-time. For black holes with different dimensions, establishing a set of appropriate matrices γμ for the general covariant Dirac equation plays an important role in the semi-classical tunneling method. By constructing two sets of γμ matrices, we have successfully derived the tunneling probability and Hawking temperature of the black holes.
Directory of Open Access Journals (Sweden)
E. V. B. Leite
2015-01-01
Full Text Available Based on the Kaluza-Klein theory, we study the Aharonov-Bohm effect for bound states for a relativistic scalar particle subject to a Coulomb-type potential. We introduce this scalar potential as a modification of the mass term of the Klein-Gordon equation, and a magnetic flux through the line element of the Minkowski spacetime in five dimensions. Then, we obtain the relativistic bound states solutions and calculate the persistent currents.
Cosmic Super-Strings and Kaluza-Klein Modes
Dufaux, Jean-Francois
2011-01-01
Cosmic super-strings interact generically with a tower of relatively light and / or strongly coupled Kaluza-Klein (KK) modes associated with the geometry of the internal space. In this paper, we study the production of spin-2 KK particles by cusps on loops of cosmic F- and D-strings. We consider cosmic super-strings localized either at the bottom of a warped throat or in a flat internal space with large volume. The total energy emitted by cusps in KK modes is of the same order of magnitude in both cases, although the number of produced KK modes may differ significantly. The calculation lies within the regime of validity of the effective Nambu-Goto description, but the energy emitted in KK modes is comparable to the energy released in scalar and gauge fields by cusp annihilation on standard Abelian-Higgs cosmic strings. Nevertheless, KK emission by cosmic super-strings may have specific cosmological consequences. We show that it is constrained by the diffuse gamma ray background and by the photo-dissociation o...
Cosmic Super-Strings and Kaluza-Klein Modes
Dufaux, Jean-Francois
2012-01-01
Cosmic super-strings interact generically with a tower of relatively light and/or strongly coupled Kaluza-Klein (KK) modes associated with the geometry of the internal space. In this paper, we study the production of spin-2 KK particles by cusps on loops of cosmic F- and D-strings. We consider cosmic super-strings localized either at the bottom of a warped throat or in a flat internal space with large volume. The total energy emitted by cusps in KK modes is comparable in both cases, although the number of produced KK modes may differ significantly. We then show that KK emission is constrained by the photo-dissociation of light elements and by observations of the diffuse gamma ray background. We study the resulting constraints on the parameter space of cosmic super-strings and highlight their complementarity with the regions that can be probed by current and upcoming gravitational wave experiments. KK modes are also expected to play an important role in the friction-dominated epoch of cosmic super-string evolu...
Thermodynamics, Euclidean Gravity and Kaluza-Klein Reduction
Fursaev, D V
2001-01-01
The aim of this paper is to find out a correspondence between one-loop effective action $W_E$ defined by means of path integral in Euclidean gravity and the free energy $F$ obtained by summation over the modes. The analysis is given for quantum fields on stationary space-times of a general form. For such problems a convenient procedure of a "Wick rotation" from Euclidean to Lorentzian theory becomes quite non-trivial implying transition from one real section of a complexified space-time manifold to another. We formulate conditions under which $F$ and $W_E$ can be connected and establish an explicit relation of these functionals. Our results are based on the Kaluza-Klein method which enables one to reduce the problem on a stationary space-time to equivalent problem on a static space-time in the presence of a gauge connection. As a by-product, we discover relation between the asymptotic heat-kernel coefficients of elliptic operators on a $D$ dimensional stationary space-times and the heat-kernel coefficients of...
Teleparallel Conformal Invariant Models induced by Kaluza-Klein Reduction
Geng, Chao-Qiang
2016-01-01
We study the extensions of teleparallism in the Kaluza-Klein (KK) scenario by writing the analogous form to the torsion scalar $T_{\\text{NGR}}$ in terms of the corresponding antisymmetric tensors, given by $T_{\\text{NGR}} = a\\,T_{ijk} \\, T^{ijk} + b\\,T_{ijk} \\,T^{kji} + c\\,T^{j}{}_{ji} \\, T^{k}{}_{k}{}^{i}$, in the four-dimensional New General Relativity (NGR) with arbitrary coefficients $a$, $b$ and $c$. After the KK dimensional reduction, the Lagrangian in the Einstein-frame can be realized by taking $2a+b+c=0$ with the ghost-free condition $c\\leq0$ for the one-parameter family of teleparallelism. We demonstrate that the conformal invariant gravity models can be constructed by the requirement of $2a+b+4c=0$ or $2a+b=0$. In particular, this conformal gravity is described on the Weyl-Cartan geometry $Y_4$ with the ghost-free condition $c>0$. We also consider the weak field approximation and discuss the non-minimal coupled term of the scalar current and torsion vector. For the conformal invariant models with $...
Lightest Kaluza-Klein graviton mode in a back-reacted Randall-Sundrum scenario
Energy Technology Data Exchange (ETDEWEB)
Das, Ashmita [Indian Institute of Technology, Department of Physics, Guwahati, Assam (India); SenGupta, Soumitra [Indian Association for the Cultivation of Science, Department of Theoretical Physics, Kolkata (India)
2016-08-15
In search of the extra dimensions in the ongoing LHC experiments, the signatures of the Randall-Sundrum (RS) lightest KK graviton have been in the main focus in recent years. The recent data from the dilepton decay channel at the LHC has determined the experimental lower bound on the mass of the RS lightest Kaluza-Klein (KK) graviton for different choices of the underlying parameters of the theory. In this work we explore the effects of the back-reaction of the bulk scalar field, which is employed to stabilise the RS model, in modifying the couplings of the lightest KK graviton with the standard model matter fields located on the visible brane. In such a modified background geometry we show that the coupling of the lightest KK graviton with the SM matter fields gets a significant suppression due to the inclusion of the back-reaction of the bulk stabilising scalar field. This implies that the back-reaction parameter weakens the signals from the RS scenario in collider experiments, which in turn explains the non-visibility of KK graviton in colliders. Thus we show that the modulus stabilisation plays a crucial role in the search of warped extra dimensions in collider experiments. (orig.)
Lightest Kaluza-Klein graviton mode in a back-reacted Randall-Sundrum scenario
Das, Ashmita; SenGupta, Soumitra
2016-08-01
In search of the extra dimensions in the ongoing LHC experiments, the signatures of the Randall-Sundrum (RS) lightest KK graviton have been in the main focus in recent years. The recent data from the dilepton decay channel at the LHC has determined the experimental lower bound on the mass of the RS lightest Kaluza-Klein (KK) graviton for different choices of the underlying parameters of the theory. In this work we explore the effects of the back-reaction of the bulk scalar field, which is employed to stabilise the RS model, in modifying the couplings of the lightest KK graviton with the standard model matter fields located on the visible brane. In such a modified background geometry we show that the coupling of the lightest KK graviton with the SM matter fields gets a significant suppression due to the inclusion of the back-reaction of the bulk stabilising scalar field. This implies that the back-reaction parameter weakens the signals from the RS scenario in collider experiments, which in turn explains the non-visibility of KK graviton in colliders. Thus we show that the modulus stabilisation plays a crucial role in the search of warped extra dimensions in collider experiments.
Gravitational Kaluza-Klein modes in the String-Cigar Braneworld
Veras, D F S; Cruz, W T; Almeida, C A S
2014-01-01
In this work the gravitational Kaluza-Klein (KK) modes are analysed on string-like braneworlds in six dimensions, namely the thin string-like Gherghetta-Shaposhnikov (GS) and the thick string-cigar model. We find a new massless mode in both modes satisfying the respective Schroedinger equation. By means of numerical analysis for both models, a complete graviton spectrum and eigenfunctions is attained. Besides the linear regime, the KK spectrum exhibits a decreasing behavior with an asymmetric mass gap with respect to the massless mode. The discontinuity is bigger in the GS model, and it is invariant upon the geometrical flow. A massive mode is obtained in the GS model with a tiny mass which does not match in any regime. It turns out that in the string-cigar model, the core brane structure smoothes and amplifies the KK modes near the brane. Further, the presence of a potential well allows the existence of resonant massive gravitons for small masses in the string-cigar scenario.
Strong gravitational lensing in a rotating Kaluza-Klein black hole with squashed horizons
Ji, LiYong; Jing, Jiliang
2014-01-01
We have investigated the strong gravitational lensing in a rotating squashed Kaluza-Klein (KK) black hole spacetime. Our result show that the strong gravitational lensings in the rotating squashed KK black hole spacetime have some distinct behaviors from those in the backgrounds of the four-dimensional Kerr black hole and of the squashed KK G\\"{o}del black hole. In the rotating squashed KK black hole spacetime, the marginally circular photon radius $\\rho_{ps}$, the coefficient $\\bar{a}$, $\\bar{b}$, the deflection angle $\\alpha(\\theta)$ in the $\\phi$ direction and the corresponding observational variables are independent of whether the photon goes with or against the rotation of the background, which is different with those in the usual four-dimensional Kerr black hole spacetime. Moreover, we also find that with the increase of the scale of extra dimension $\\rho_0$, the marginally circular photon radius $\\rho_{ps}$ and the angular position of the relativistic images $\\theta_\\infty$ first decreases and then inc...
Superconformal symmetry in the Kaluza-Klein spectrum of warped AdS(3)
Energy Technology Data Exchange (ETDEWEB)
Schmude, Johannes; Vasilakis, Orestis [Department of Physics, Universidad de Oviedo, Avda. Calvo Sotelo 18, 33007, Oviedo (Spain)
2016-10-18
We study the Kaluza-Klein spectrum of warped AdS{sub 3} compactifications of type IIB with five-form flux which are dual to N=(0,2) SCFTs in two dimensions. We prove that the spectra of fluctuations of both the spin 2 sector of the graviton and the axio-dilaton are bounded. At the bound the modes have the correct quantum numbers to be chiral primaries and descendants thereof respectively. Moreover, we prove that the same modes give rise to superpartners in the dilatino spectrum. Our results show that a subset of the mesonic chiral ring of the dual SCFT is isomorphic to the first Kohn-Rossi cohomology groups. As an example, we consider the compactification of four-dimensional Y{sup p,q} theories on Riemann surfaces for the case of the universal twist. We conclude by studying fluctuations of the three-form, where we are able to identify Betti multiplets after imposing some mild assumptions.
Scale Invariant Kaluza-Klein Theory and the Fate of the Gravitational Collapse
Quirós, I
2002-01-01
Pushing forward the similitudes between the gravitational collapse and the expansion of the universe (in the reversed sense of time), it should be expected that, during the collapse, eventually, a spacetime domain would be reached where attained energy scales are very high. In consequence some of the compactified extra dimensions may be decompactified and some presently broken symmetries may be restored. A more fundamental theory (of which Einstein's theory is a symmetry broken phase) is then expected to take account of further description of the collapse. I propose a simple (classical) model for the description of the late stages of the gravitational collapse: A non-Riemannian, scale-invariant version of 5-dimensional Kaluza-Klein theory in which the standard Riemann structure of the higher-dimensional manifold is replaced by a Weyl-integrable one. A class of solutions, that generalize the "soliton" one by Gross and Perry and Davidson and Owen, is found. This class contains both naked singularities and wormh...
Energy Technology Data Exchange (ETDEWEB)
Kurita, Yasunari [Osaka City University Advanced Mathematical Institute, Osaka 558-8585 (Japan); Ishihara, Hideki [Department of Mathematics and Physics, Osaka City University, Osaka 558-8585 (Japan)], E-mail: kurita@sci.osaka-cu.ac.jp, E-mail: ishihara@sci.osaka-cu.ac.jp
2008-04-21
We investigate thermodynamics constructed on different background reference spacetimes for squashed Kaluza-Klein (SqKK) black hole and electrically charged black string in the five-dimensional Einstein-Maxwell system. Two spacetimes are possible to be reference spacetimes giving finite gravitational classical actions: one is four-dimensional Minkowski times a circle and the other is the KK monopole. The boundary of the SqKK black hole cannot be matched perfectly to that of the former reference spacetime because of the difference in topology. However, the resultant classical action coincides with that calculated by the counterterm subtraction scheme. The boundary of the KK monopole has the same topology as that of the SqKK black hole and can be matched to the boundary of the black hole perfectly. The resultant action takes a different value from the result given by using the former reference spacetime. After a brief review of thermodynamic quantities of the black hole solutions, we calculate thermodynamic potentials relevant for several thermodynamic environments. The most stable state is different for each environment: for example, the KK monopole is the most stable state in an isothermal environment with fixed gravitational tension. On the other hand, when the size of the extra dimension is fixed, the Minkowski times a circle is the most stable. It is shown that these two spacetimes can be reference spacetimes of the five-dimensional black string.
Kaluza-Klein theories as a tool to find new gauge symmetries
Dolan, L.
Non-abelian Kaluza-Klein theories are studied with respect to using the invariances of multi-dimensional general relativity to investigate hidden symmetry, such as Kac-Mody Lie algebras, of the four-dimensional Yang-Mills theory. Several properties of the affine transformations on the self-dual set are identified and are used to motivate the Kaluza-Klein analysis. In this context, a system of differential equations is derived for new symmetry transformations which may be extendable to the full gauge theory.
Hawking Radiation of a Kaluza-Klein Black Hole Described by Landauer Transport Model
Institute of Scientific and Technical Information of China (English)
兰小刚; 韦联福
2012-01-01
We investigate the Hawking radiation of a Kaluza-Klein black hole by using one-dimensional(1D),non-equilibrium,Landauer transport model.The derived Hawking radiation temperature is in consistence with that obtained by using the usual anomaly method.With the Landauer transport model,we calculate the entropy flow out of the Kaluza-Klein black hole and the relevant entropy production rate.How these quantities depending on the physical parameters of the black hole is also discussed.
Karsai, Szilvia; Forgács-Dajka, Emese; Pósfay, Péter
2016-01-01
We present the correspondence between non-interacting multi-hadron fermion star equation of state in the many-flavor limit and the degrees of freedom of a Kaluza\\,--\\,Klein compact star. Many flavors can be interpreted in this framework as one extra compacti\\-fied spatial dimension with various, more-and-more massive hadron state excitations. The effect of increasing the degrees of freedom was investigated on the equation of state and in connection with the mass-radius relation, $M(R)$. The maximum mass of the star, $M_{\\mathrm{max}}$ were also calculated as a function of the maximum number of excited states, $n$ and the size of the compactified extra dimension, $R_{\\mathrm{c}}$.
Deformed phase space Kaluza-Klein cosmology and late time acceleration
Sabido, M.; Yee-Romero, C.
2016-06-01
The effects of phase space deformations on Kaluza-Klein cosmology are studied. The deformation is introduced by modifying the symplectic structure of the minisuperspace variables. In the deformed model, we find an accelerating scale factor and therefore infer the existence of an effective cosmological constant from the phase space deformation parameter β.
T-Duality in $\\sigma$ Models with Kaluza-Klein Metric as Electric-Magnetic Duality
Jafarizadeh, M A
1999-01-01
It is shown that the T-duality in \\sigma-model with Kaluza-Klein metric, without or with a torsion term, can be interpreted as electric-magnetic duality for some of their solitonic solutions. Actually Buscher's duality transformation interchanges the topological and Noether charges.
New phases of thermal SYM and LST from Kaluza-Klein black holes
DEFF Research Database (Denmark)
Harmark, Troels; Obers, Niels A.
2005-01-01
We review the recently found map that takes any static and neutral Kaluza-Klein black hole, i.e. any static and neutral black hole on Minkowski-space times a circle Md × S1, and maps it to a corresponding solution for a non- and near-extremal brane on a circle. This gives a precise connection...
New phases of thermal SYM and LST from Kaluza-Klein black holes
DEFF Research Database (Denmark)
Harmark, Troels; Obers, Niels A.
2005-01-01
We review the recently found map that takes any static and neutral Kaluza-Klein black hole, i.e. any static and neutral black hole on Minkowski-space times a circle Md × S1, and maps it to a corresponding solution for a non- and near-extremal brane on a circle. This gives a precise connection...... between phases of Kaluza-Klein black holes and the thermodynamic behavior of the non-gravitational theories dual to near-extremal branes on a circle. In particular, for the thermodynamics of strongly-coupled supersymmetric Yang-Mills theories on a circle we predict the existence of a new non-uniform phase...
Particle production and dissipation caused by the Kaluza-Klein tower
Matsuda, Tomohiro
2012-01-01
Two-step dissipation is studied in supersymmetric models in which the field in motion couples to bulk fields in the higher dimensional space. Since the Kaluza-Klein tower of the intermediate field changes its mass-spectrum during the evolution, there could be back-reaction from the tower. Then the system may eventually cause significant dissipation of the kinetic energy if the tower is coupled to light fields in the thermal bath. To see what happens in the higher dimensional theory, we consider three models for the scenario, which are carefully prepared. In these models the extension is obvious but it does not disturb the original set-ups. The third model suggests that the evolution of the volume moduli may feel significant friction from the Kaluza-Klein tower.
Dynamical Fermion Masses Under the Influence of Kaluza-Klein Fermions in Randall-Sundrum Background
Abe, H; Muta, T; Abe, Hiroyuki; Inagaki, Tomohiro; Muta, Taizo
2001-01-01
The dynamical fermion mass generation on the D3-brane in the Randall-Sundrum space-time is discussed in a model with bulk fermions in interaction with fermions on the branes. It is found that the dynamical fermion masses are generated at the natural (R.-S.) radius of the compactified extra space and may be made small compared with masses of the Kaluza-Klein modes which is of order of TeV.
Killig-Yano Tensors of Valence-2 in the Standart Kaluza-Klein Theory
Nurbaki, Ali Nur
2011-01-01
This work is constructed on two main concepts: Killing-Yano symmetry and the Kaluza-Klein theory. Those concepts are reviewed in the first three chapters. In the fourth chapter firstly Killing-Yano equations of valence-2 are obtained for a general 5-dimensional metric and then reduced for the Minkowski metric. It is seen that in order to save the existence of Killing-Yano tensors with the fifth components some conditions must be satisfied
Kaluza-Klein magnetized cylindrical wormhole and its gravitational lensing
Hashemi, S. Sedigheh; Riazi, Nematollah
2016-10-01
A new exact vacuum solution in five dimensions, which describes a magnetized cylindrical wormhole in 3+1 dimensions is presented. The magnetic field lines are stretched along the wormhole throat and are concentrated near to it. We study the motion of neutral and charged test particles under the influence of the magnetized wormhole. The effective potential for a neutral test particle around and across the magnetized wormhole has a repulsive character. The gravitational lensing for the magnetized wormhole for various lens parameters are calculated and compared. The total magnetic flux on either side of the wormhole is obtained. We present analytic expressions which show regions in which the null energy condition is violated.
Shadow cast by a Kaluza-Klein spinning dilaton black hole
Amarilla, Leonardo
2015-01-01
We examine the shadow of a rotating Kaluza-Klein black hole in Einstein gravity coupled to a Maxwell field and a dilaton. The size and the shape of the shadow depend on the mass, the charge, and the angular momentum of the compact object. For a given mass, the size increases with the rotation parameter and decreases with the electric charge. The distortion with respect to the non rotating case grows with the charge and the rotation parameter. For fixed values of these parameters, the shadow is slightly larger and less deformed than in the Kerr-Newman case.
Hawking Radiation of the Charged Particle via Tunneling from the Kaluza-Klein Black Hole
Pu, Jin; Han, Yan
2016-12-01
In this paper, by applying the Lagrangian analysis on the action, we first redefine the geodesic equation of the charged massive particle. Then, basing on the new definition of the geodesic equation, we revisit the Hawking radiation of the charged massive particle via tunneling from the event horizon of the Kaluza-Klein black hole. In our treatment, the geodesic equation of the charged massive particle is defined uniformly with that of the massless particle, which overcomes the shortcomings of its previous definition, and is more suitable for the tunneling mechanism. The highlight of our work is a new and important development for the Parikh-Wilczek's tunneling method.
Graviton Kaluza-Klein modes in nonflat branes with stabilized modulus
Paul, Tanmoy; SenGupta, Soumitra
2016-04-01
We consider a generalized two brane Randall-Sundrum model where the branes are endowed with nonzero cosmological constant. In this scenario, we re-examine the modulus stabilization mechanism and the nature of Kaluza-Klein (KK) graviton modes. Our result reveals that while the KK mode graviton masses may change significantly with the brane cosmological constant, the Goldberger-Wise stabilization mechanism, which assumes a negligible backreaction on the background metric, continues to hold even when the branes have a large cosmological constant. The possibility of having a global minimum for the modulus is also discussed. Our results also include an analysis for the radion mass in this nonflat brane scenario.
Hawking Radiation of the Charged Particle via Tunneling from the Kaluza-Klein Black Hole
Pu, Jin; Han, Yan
2016-08-01
In this paper, by applying the Lagrangian analysis on the action, we first redefine the geodesic equation of the charged massive particle. Then, basing on the new definition of the geodesic equation, we revisit the Hawking radiation of the charged massive particle via tunneling from the event horizon of the Kaluza-Klein black hole. In our treatment, the geodesic equation of the charged massive particle is defined uniformly with that of the massless particle, which overcomes the shortcomings of its previous definition, and is more suitable for the tunneling mechanism. The highlight of our work is a new and important development for the Parikh-Wilczek's tunneling method.
Reconstruction of Scalar Field Dark Energy Models in Kaluza-Klein Universe
Institute of Scientific and Technical Information of China (English)
M.Sharif; Abdul Jawad
2013-01-01
This paper is devoted to study the modified holographic dark energy model by taking its different aspects in the flat Kaluza-Klein universe.We construct the equation of state parameter which evolutes the universe from quintessence region towards the vacuum.It is found that the modified holographic model exhibits instability against small perturbations in the early epoch of the universe but becomes stable in the later times.We also develop its correspondence with some scalar field dark energy models.It is interesting to mention here that all the results are consistent with the present observations.
Gauged motion in general relativity and in Kaluza-Klein theories
Nouri-Zonoz, M; Nouri-Zonoz, Mohammad; Tavanfar, Ali Reza
2003-01-01
In a recent paper [1] a new generalization of Killing motion, the {\\it gauged motion}, has been introduced for stationary spacetimes where it was shown that the physical symmetries of such spacetimes are well described through this new symmetry. In this article after a more detailed study in stationary case we present the definition of gauged motion for general spacetimes. The definition is based on the gauged Lie derivative induced by a threading family of observers and the relevant reparametrization invariance. We also extend the gauged motion to the case of Kaluza-Klein theories.
State-space geometry, non-extremal black holes and Kaluza-Klein monopoles
Bellucci, Stefano
2012-01-01
We examine the statistical nature of the charged anticharged non-extremal black holes in string theory. From the perspective of the intrinsic Riemannian Geometry, the first principle of the statistical mechanics shows that the stability properties of general nonextremal nonlarge charged black brane solutions are divulged from the positivity of the corresponding principle minors of the space-state metric tensor. Under the addition of the Kaluza-Klein monopoles, a novel aspect of the Gaussian fluctuations demonstrates that the canonical fluctuations can be ascertained without any approximation. We offer the state-space geometric implication for the most general non-extremal black brane configurations in string theory.
Mass and Free energy in Thermodynamics of Squashed Kaluza-Klein Black Holes
Kurita, Yasunari
2007-01-01
The Abbott-Deser mass, the Hamiltonian and the Komar mass of the 5-dimensional Kaluza-Klein black hole with squashed horizons take different values. Introducing a new couple of thermodynamic variables for the Komar mass, we show that each mass can be interpreted as a thermodynamic potential with its own natural variables, i.e. all masses are related to each other by the Legendre transformations. It is found that the new variables and the gravitational tension represent the squashing of the outer horizon.
Mass and free energy in the thermodynamics of squashed Kaluza-Klein black holes
Energy Technology Data Exchange (ETDEWEB)
Kurita, Yasunari [Advanced Mathematical Institute, Osaka City University, Osaka 558-8585 (Japan); Ishihara, Hideki [Department of Mathematics and Physics, Osaka City University, Osaka 558-8585 (Japan)
2007-09-07
The Abbott-Deser mass, the Hamiltonian and the Komar mass of the five-dimensional Kaluza-Klein black hole with squashed horizons take different values. Introducing a new couple of thermodynamic variables for the Komar mass, we show that each mass can be interpreted as a thermodynamic potential with its own natural variables, i.e. all masses are related to each other by the Legendre transformations. It is found that the new variables and the gravitational tension represent the squashing of the outer horizon.
Dimensional Reduction of the 5D Kaluza-Klein Geodesic Deviation Equation
Lacquaniti, V; Vietri, F; 10.1007/s10714-009-0853-3
2009-01-01
In the work of Kerner et al. (2001) the problem of the geodesic deviation in a 5D Kaluza Klein background is faced. The 4D space-time projection of the resulting equation coincides with the usual geodesic deviation equation in the presence of the Lorenz force, provided that the fifth component of the deviation vector satisfies an extra constraint which takes into account the $q/m$ conservation along the path. The analysis was performed setting as a constant the scalar field which appears in Kaluza-Klein model. Here we focus on the extension of such a work to the model where the presence of the scalar field is considered. Our result coincides with that of Kerner et al. when the minimal case $\\phi=1$ is considered, while it shows some departures in the general case. The novelty due to the presence of $\\phi$ is that the variation of the $q/m$ between the two geodesic lines is not conserved during the motion; an exact law for such a behaviour has been derived.
Light Kaluza Klein States in Randall-Sundrum Models with Custodial SU(2)
Energy Technology Data Exchange (ETDEWEB)
Carena, Marcela; /Fermilab; Ponton, Eduardo; /Columbia U.; Santiago, Jose; /Fermilab; Wagner, Carlos E.M.; /Argonne /Chicago U., EFI /KICP, Chicago
2006-07-01
We consider Randall-Sundrum scenarios based on SU(2){sub L} x SU(2){sub R} and a discrete parity exchanging L with R. The custodial and parity symmetries can be used to make the tree level contribution to the T parameter and the anomalous couplings of the bottom quark to the Z very small. We show that the resulting quantum numbers typically induce a negative T parameter at one loop that, together with the positive value of the S parameter, restrict considerably these models. There are nevertheless regions of parameter space that successfully reproduce the fit to electroweak precision observables with light Kaluza-Klein excitations accessible at colliders. We consider models of gauge-Higgs unification that implement the custodial and parity symmetries and find that the electroweak data singles out a very well defined region in parameter space. In this region one typically finds light gauge boson Kaluza-Klein excitations as well as light SU(2){sub L} singlet, and sometimes also doublet, fermionic states, that mix with the top quark, and that may yield interesting signatures at future colliders.
Kaluza-Klein-Carmeli Metric from Quaternion-Clifford Space, Lorentz' Force, and Some Observables
Directory of Open Access Journals (Sweden)
Christianto V.
2008-04-01
Full Text Available It was known for quite long time that a quaternion space can be generalized to a Clifford space, and vice versa; but how to find its neat link with more convenient metric form in the General Relativity theory, has not been explored extensively. We begin with a representation of group with non-zero quaternions to derive closed FLRW metric [1], and from there obtains Carmeli metric, which can be extended further to become 5D and 6D metric (which we propose to call Kaluza-Klein-Carmeli metric. Thereafter we discuss some plausible implications of this metric, beyond describing a galaxy’s spiraling motion and redshift data as these have been done by Carmeli and Hartnett [4, 5, 6]. In subsequent section we explain Podkletnov’s rotating disc experiment. We also note possible implications to quantum gravity. Further observations are of course recommended in order to refute or verify this proposition.
Redshift in a six-dimensional classical Kaluza-Klein type model
Syska, Jacek
2015-01-01
Multidimensional theories still remain attractive from the point of view of better understanding fundamental interactions. In this paper a six-dimensional Kaluza-Klein type model at the classical, Einstein's gravity formulation is considered. The static spherically symmetric solution of the six-dimensional Einstein equations coupled to the Klein-Gordon equation with the massless dilatonic field is presented. As it is horizon free, it is fundamentally different from the four-dimensional Schwarzschild solution. The motion of test particles in such a spherically symmetric configuration is then analyzed. The presence of the dilatonic field has a similar dynamical effect as the existence of additional massive matter. The emphasis is put on some observable quantities like redshifts. It has been suggested that strange features of emission lines from galactic nuclei as well as quasar-galaxy associations may in fact be manifestations of the multidimensionality of the world.
Casimir Effect Near the Future Singularity in Kaluza Klein Viscous Cosmology
Khadekar, G. S.
2016-02-01
In this paper we investigate the analytical properties of the scalar expansion θ in the cosmic fluid close to the future singularity, when the fluid possesses a constant bulk viscosity ζ in the framework of Kaluza-Klein theory of gravitation. In addition, we assume the viscous cosmology theories in the sense that the Casimir contributions to the energy density and pressure are both proportional to 1/ a 4, where a being scale factor. We also worked out the series expansion for the scalar expansion θ under the condition that the Casimir influence is small. However, near to the big rip singularity the Casimir term has to fade away and we obtain the same singularity behavior for the scalar expansion θ, energy density ρ, the scale factor a as in the Casimir-free viscous case.
Supersymmetric and Kaluza-Klein Particles Multiple Scattering in the Earth
Energy Technology Data Exchange (ETDEWEB)
Albuquerque, Ivone; Klein, Spencer
2009-05-19
Neutrino telescopes with cubic kilometer volume have the potential to discover new particles. Among them are next to lightest supersymmetric (NLSPs) and next to lightest Kaluza-Klein (NLKPs) particles. Two NLSPs or NLKPs will transverse the detector simultaneously producing parallel charged tracks. The track separation inside the detector can be a few hundred meters. As these particles might propagate a few thousand kilometers before reaching the detector, multiple scattering could enhance the pair separation at the detector. We find that the multiple scattering will alter the separation distribution enough to increase the number of NLKP pairs separated by more than 100 meters (a reasonable experimental cut) by up to 46% depending on the NLKP mass. Vertical upcoming NLSPs will have their separation increased by 24% due to multiple scattering.
Tevatron constraint on the Kaluza-Klein gluon of the Bulk Randall-Sundrum model
Guchait, M; Sridhar, K
2007-01-01
The Bulk Randall-Sundrum model, where all Standard Model particles except the Higgs are free to propagate in the bulk, predicts the existence of Kaluza-Klein (KK) modes of the gluon with a large branching into top-antitop pairs. We study the production of the lowest KK gluon mode at the Tevatron energy and use the data on the top cross-section from the Run II of Tevatron to put a bound on the mass of the KK gluon. The resulting bound of 800 GeV, while being much smaller than the constraints obtained on the KK gluon mass from flavour-changing neutral currents, is the first, direct collider bound which is independent of the specificities of the model.
Kaluza-Klein gluon + jets associated production at the Large Hadron Collider
Iyer, A.M.; Manglani, N.; Sridhar, K.
2016-01-01
The Kaluza-Klein excitations of gluons offer the exciting possibility of probing bulk Randall-Sundrum (RS) models. In these bulk models either a custodial symmetry or a deformation of the metric away from AdS is invoked in order to deal with electroweak precision tests. Addressing both these models, we suggest a new channel in which to study the production of KK-gluons ($g_{KK}$): one where it is produced in association with one or more hard jets. The cross-section for the $g_{KK}+$ jets channel is significant because of several contributing sub-processes. In particular, the 1-jet and the 2-jet associated processes are important because at these orders in QCD the $qg$ and the $gg$ initial states respectively come into play. We have performed a hadron-level simulation of the signal and present strategies to effectively extract the signal from what could potentially be a huge background. We present results for the kinematic reach of the LHC Run-II for different $g_{KK}$ masses in bulk-RS models.
Hamiltonian Map to Conformal Modification of Spacetime Metric:Kaluza-Klein and TeVeS
Horwitz, Lawrence; Schiffer, Marcelo
2009-01-01
It has been shown that the orbits of motion for a wide class of nonrelativistic Hamiltonian systems can be described as geodesic flows on a manifold and an associated dual. This method can be applied to a four dimensional manifold of orbits in spacetime associated with a relativistic system. We show that a relativistic Hamiltonian which generates Einstein geodesics, with the addition of a world scalar field, can be put into correspondence with another Hamiltonian with conformally modified metric. Such a construction could account for part of the requirements of Bekenstein for achieving the MOND theory of Milgrom in the post-Newtonian limit. The constraints on the MOND theory imposed by the galactic rotation curves, through this correspondence, would then imply constraints on the structure of the world scalar field. We then use the fact that a Hamiltonian with vector gauge fields results, through such a conformal map, in a Kaluza-Klein type theory, and indicate how the TeVeS structure can be put into this fram...
Kaluza-Klein cosmological model in f(R, T) gravity with Λ(T)
Sahoo, P. K.; Mishra, B.; Tripathy, S. K.
2016-04-01
A class of Kaluza-Klein cosmological models in $f(R,T)$ theory of gravity have been investigated. In the work, we have considered the functional $f(R,T)$ to be in the form $f(R,T)=f(R)+f(T)$ with $f(R)=\\lambda R$ and $f(T)=\\lambda T$. Such a choice of the functional $f(R,T)$ leads to an evolving effective cosmological constant $\\Lambda$ which depends on the stress energy tensor. The source of the matter field is taken to be a perfect cosmic fluid. The exact solutions of the field equations are obtained by considering a constant deceleration parameter which leads two different aspects of the volumetric expansion namely a power law and an exponential volumetric expansion. Keeping an eye on the accelerating nature of the universe in the present epoch, the dynamics and physical behaviour of the models have been discussed. From statefinder diagnostic pair we found that the model with exponential volumetric expansion behaves more like a $\\Lambda$CDM model.
Kaluza-Klein gluon + jets associated production at the Large Hadron Collider
Iyer, A. M.; Mahmoudi, F.; Manglani, N.; Sridhar, K.
2016-08-01
The Kaluza-Klein excitations of gluons offer the exciting possibility of probing bulk Randall-Sundrum (RS) models. In these bulk models either a custodial symmetry or a deformation of the metric away from AdS is invoked in order to deal with electroweak precision tests. Addressing both these models, we suggest a new channel in which to study the production of KK-gluons (gKK): one where it is produced in association with one or more hard jets. The cross-section for the gKK + jets channel is significant because of several contributing sub-processes. In particular, the 1-jet and the 2-jet associated processes are important because at these orders in QCD the qg and the gg initial states respectively come into play. We have performed a hadron-level simulation of the signal and present strategies to effectively extract the signal from what could potentially be a huge background. We present results for the kinematic reach of the LHC Run-II for different gKK masses in bulk-RS models.
A new approach to static numerical relativity, and its application to Kaluza-Klein black holes
Headrick, Matthew; Wiseman, Toby
2009-01-01
We propose a general framework for solving the Einstein equation for static and Euclidean metrics. First, we address the issue of gauge-fixing by borrowing from the Ricci-flow literature the so-called DeTurck trick, which renders the Einstein equation strictly elliptic and generalizes the usual harmonic-coordinate gauge. We then study two algorithms, Ricci-flow and Newton's method, for solving the resulting Einstein-DeTurck equation. We illustrate the use of these methods by studying localized black holes and non-uniform black strings in five-dimensional Kaluza-Klein theory, improving on previous calculations of their thermodynamic and geometric properties. We study spectra of various operators for these solutions, in particular finding negative modes of the Lichnerowicz operator. We classify the localized solutions into two branches that meet at a minimum temperature. We find good evidence for a merger between the localized and non-uniform solutions. We also find a narrow window of localized solutions that p...
Photo-production of a 750 GeV di-photon resonance mediated by Kaluza-Klein leptons in the loop
Abel, Steven; Khoze, Valentin V.
2016-05-01
We consider the phenomenology of a 750 GeV resonance X which can be produced at the LHC by only photon fusion and subsequently decay into di-photons. We propose that the spin-zero state X is coupled to a heavy lepton that lives in the bulk of a higher-dimensional theory and interacts only with the photons of the Standard Model. We compute the di-photon rate in these models with two and more compact extra dimensions and demonstrate that they allow for a compelling explanation of the di-photon excess recently observed by the ATLAS and CMS collaborations. The central role in our approach is played by the summation over the Kaluza-Klein modes of the new leptons, thus providing a significant enhancement of the X → γγ loops for the production and decay subprocesses. It is expected that the jet activity accompanying these purely electromagnetic (at the partonic level) processes is numerically suppressed by factors such as {α}_{em}^2{{C}}_{qoverline{q}}/{{C}}_{γ γ}˜ 1{0}^{-3}.
Photo-production of a 750 GeV di-photon resonance mediated by Kaluza-Klein leptons in the loop
Abel, Steven
2016-01-01
We consider the phenomenology of a 750 GeV resonance X which can be produced at the LHC by only photon fusion and subsequently decay into di-photons. We propose that the spin-zero state X is coupled to a heavy lepton that lives in the bulk of a higher-dimensional theory and interacts only with the photons of the Standard Model. We compute the di-photon rate in these models with two and more compact extra dimensions and demonstrate that they allow for a compelling explanation of the di-photon excess recently observed by the ATLAS and CMS collaborations. The central role in our approach is played by the summation over the Kaluza-Klein modes of the new leptons, thus providing a significant enhancement of the $X\\to \\gamma\\gamma$ loops for the production and decay subprocesses. It is expected that the jet activity accompanying these purely electromagnetic (at the partonic level) processes is numerically suppressed by factors such as $\\alpha_{em}^2 C_{q\\bar{q}}/C_{\\gamma\\gamma}\\sim 10^{-3}$.
Energy Technology Data Exchange (ETDEWEB)
IceCube Collaboration; Abbasi, R.; al., et
2009-10-23
A search for muon neutrinos from Kaluza-Klein dark matter annihilations in the Sun has been performed with the 22-string configuration of the IceCube neutrino detector using data collected in 104.3 days of live-time in 2007. No excess over the expected atmospheric background has been observed. Upper limits have been obtained on the annihilation rate of captured lightest Kaluza-Klein particle (LKP) WIMPs in the Sun and converted to limits on the LKP-proton cross-sections for LKP masses in the range 250 - 3000 GeV. These results are the most stringent limits to date on LKP annihilation in the Sun.
Abbasi, R.; Abdou, Y.; Abu-Zayyad, T.; Adams, J.; Aguilar, J. A.; Ahlers, M.; Andeen, K.; Auffenberg, J.; Bai, X.; Baker, M.; Barwick, S. W.; Bay, R.; Bazo Alba, J. L.; Beattie, K.; Beatty, J. J.; Bechet, S.; Becker, J. K.; Becker, K.-H.; Benabderrahmane, M. L.; Berdermann, J.; Berghaus, P.; Berley, D.; Bernardini, E.; Bertrand, D.; Besson, D. Z.; Bissok, M.; Blaufuss, E.; Boersma, D. J.; Bohm, C.; Bolmont, J.; Botner, O.; Bradley, L.; Braun, J.; Breder, D.; Carson, M.; Castermans, T.; Chirkin, D.; Christy, B.; Clem, J.; Cohen, S.; Cowen, D. F.; D'Agostino, M. V.; Danninger, M.; Day, C. T.; de Clercq, C.; Demirörs, L.; Depaepe, O.; Descamps, F.; Desiati, P.; de Vries-Uiterweerd, G.; Deyoung, T.; Díaz-Vélez, J. C.; Dreyer, J.; Dumm, J. P.; Duvoort, M. R.; Edwards, W. R.; Ehrlich, R.; Eisch, J.; Ellsworth, R. W.; Engdegård, O.; Euler, S.; Evenson, P. A.; Fadiran, O.; Fazely, A. R.; Feusels, T.; Filimonov, K.; Finley, C.; Foerster, M. M.; Fox, B. D.; Franckowiak, A.; Franke, R.; Gaisser, T. K.; Gallagher, J.; Ganugapati, R.; Gerhardt, L.; Gladstone, L.; Goldschmidt, A.; Goodman, J. A.; Gozzini, R.; Grant, D.; Griesel, T.; Groß, A.; Grullon, S.; Gunasingha, R. M.; Gurtner, M.; Ha, C.; Hallgren, A.; Halzen, F.; Han, K.; Hanson, K.; Hasegawa, Y.; Helbing, K.; Herquet, P.; Hickford, S.; Hill, G. C.; Hoffman, K. D.; Homeier, A.; Hoshina, K.; Hubert, D.; Huelsnitz, W.; Hülß, J.-P.; Hulth, P. O.; Hultqvist, K.; Hussain, S.; Imlay, R. L.; Inaba, M.; Ishihara, A.; Jacobsen, J.; Japaridze, G. S.; Johansson, H.; Joseph, J. M.; Kampert, K.-H.; Kappes, A.; Karg, T.; Karle, A.; Kelley, J. L.; Kemming, N.; Kenny, P.; Kiryluk, J.; Kislat, F.; Klein, S. R.; Knops, S.; Kohnen, G.; Kolanoski, H.; Köpke, L.; Koskinen, D. J.; Kowalski, M.; Kowarik, T.; Krasberg, M.; Krings, T.; Kroll, G.; Kuehn, K.; Kuwabara, T.; Labare, M.; Lafebre, S.; Laihem, K.; Landsman, H.; Lauer, R.; Lehmann, R.; Lennarz, D.; Lucke, A.; Lundberg, J.; Lünemann, J.; Madsen, J.; Majumdar, P.; Maruyama, R.; Mase, K.; Matis, H. S.; McParland, C. P.; Meagher, K.; Merck, M.; Mészáros, P.; Meures, T.; Middell, E.; Milke, N.; Miyamoto, H.; Montaruli, T.; Morse, R.; Movit, S. M.; Nahnhauer, R.; Nam, J. W.; Nießen, P.; Nygren, D. R.; Odrowski, S.; Olivas, A.; Olivo, M.; Ono, M.; Panknin, S.; Patton, S.; Paul, L.; Pérez de Los Heros, C.; Petrovic, J.; Piegsa, A.; Pieloth, D.; Pohl, A. C.; Porrata, R.; Potthoff, N.; Price, P. B.; Prikockis, M.; Przybylski, G. T.; Rawlins, K.; Redl, P.; Resconi, E.; Rhode, W.; Ribordy, M.; Rizzo, A.; Rodrigues, J. P.; Roth, P.; Rothmaier, F.; Rott, C.; Roucelle, C.; Rutledge, D.; Ruzybayev, B.; Ryckbosch, D.; Sander, H.-G.; Sarkar, S.; Schatto, K.; Schlenstedt, S.; Schmidt, T.; Schneider, D.; Schukraft, A.; Schulz, O.; Schunck, M.; Seckel, D.; Semburg, B.; Seo, S. H.; Sestayo, Y.; Seunarine, S.; Silvestri, A.; Slipak, A.; Spiczak, G. M.; Spiering, C.; Stamatikos, M.; Stanev, T.; Stephens, G.; Stezelberger, T.; Stokstad, R. G.; Stoufer, M. C.; Stoyanov, S.; Strahler, E. A.; Straszheim, T.; Sulanke, K.-H.; Sullivan, G. W.; Swillens, Q.; Taboada, I.; Tamburro, A.; Tarasova, O.; Tepe, A.; Ter-Antonyan, S.; Terranova, C.; Tilav, S.; Toale, P. A.; Tooker, J.; Tosi, D.; Turčan, D.; van Eijndhoven, N.; Vandenbroucke, J.; van Overloop, A.; van Santen, J.; Voigt, B.; Walck, C.; Waldenmaier, T.; Wallraff, M.; Walter, M.; Wendt, C.; Westerhoff, S.; Whitehorn, N.; Wiebe, K.; Wiebusch, C. H.; Wiedemann, A.; Wikström, G.; Williams, D. R.; Wischnewski, R.; Wissing, H.; Woschnagg, K.; Xu, C.; Xu, X. W.; Yodh, G.; Yoshida, S.; IceCube Collaboration
2010-03-01
A search for muon neutrinos from Kaluza-Klein dark matter annihilations in the Sun has been performed with the 22-string configuration of the IceCube neutrino detector using data collected in 104.3 days of live time in 2007. No excess over the expected atmospheric background has been observed. Upper limits have been obtained on the annihilation rate of captured lightest Kaluza-Klein particle (LKP) WIMPs in the Sun and converted to limits on the LKP-proton cross sections for LKP masses in the range 250-3000 GeV. These results are the most stringent limits to date on LKP annihilation in the Sun.
Energy Technology Data Exchange (ETDEWEB)
Lahrichi, N
2004-07-01
In this thesis we have put the first constraints on the fundamental parameters of the Randall-Sundrum model of extra dimensions, k/M{sub Pl} which is proportional to the coupling of the graviton to the standard model fields and M{sub G} which is the mass of the first excited state of the Kaluza-Klein graviton. The analysis performed on Monte Carlo sample of the signal allowed to find an error in the PYTHIA generator. The elaboration of an independent generator dedicated for this special analysis helped to find out and correct the error. The data sample used for the analysis covers the period running from november 2002 up to july 2003 taken by the D0 collaboration at Tevatron, which corresponds to an accumulated luminosity of 107,8 pb{sup -1}. The search for the graviton in the dimuon channel allowed to measure the Z production cross-section multiplied by the branching ratio in dimuons. (author)
Energy Technology Data Exchange (ETDEWEB)
Choudhury, Sayantan [Indian Statistical Institute, Physics and Applied Mathematics Unit, Kolkata (India); SenGupta, Soumitra [Indian Association for the Cultivation of Science, Department of Theoretical Physics, Kolkata (India)
2014-11-15
In this paper we study the role of the 5D Gauss-Bonnet corrections and two-loop higher genus contribution to the gravity action in type IIB string theory inspired low energy supergravity theory in the light of gravidilatonic interactions on the lightest Kaluza-Klein graviton mass spectrum. From the latest constraints on the lightest Kaluza-Klein graviton mass as obtained from the ATLAS dilepton search in 7 TeV proton-proton collision experiments, we have shown that due to the presence of Gauss-Bonnet and string loop corrections, the warping solution in an AdS{sub 5} bulk is quite distinct from the Randall-Sundrum scenario. We discuss the constraints on the model parameters to fit with the present ATLAS data. (orig.)
Acosta, D; Affolder, T; Akimoto, H; Albrow, M G; Ambrose, D; Amidei, D; Anikeev, K; Antos, J; Apollinari, G; Arisawa, T; Artikov, A; Asakawa, T; Ashmanskas, W; Azfar, F; Azzi-Bacchetta, P; Bacchetta, N; Bachacou, H; Badgett, W F; Bailey, S; De Barbaro, P; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Baroiant, S; Barone, M; Bauer, G; Bedeschi, F; Behari, S; Belforte, S; Bell, W H; Bellettini, Giorgio; Bellinger, J; Benjamin, D; Bensinger, J; Beretvas, A; Berryhill, J W; Bhatti, A A; Binkley, M; Bisello, D; Bishai, M; Blair, R E; Blocker, C; Bloom, K; Blumenfeld, B; Blusk, S R; Bocci, A; Bodek, A; Bölla, G; Bolshov, A; Bonushkin, Yu; Bortoletto, Daniela; Boudreau, J; Brandl, A; Bromberg, C; Brozovic, M; Brubaker, E; Bruner, N; Budagov, Yu A; Budd, H S; Burkett, K; Busetto, G; Byrum, K L; Cabrera, S; Calafiura, P; Campbell, M; Carithers, W C; Carlson, J; Carlsmith, D; Caskey, W; Castro, A; Cauz, D; Cerri, A; Cerrito, L; Chan, A W; Chang, P S; Chang, P T; Chapman, J; Chen, C; Chen, Y C; Cheng, M T; Chertok, M; Chiarelli, G; Chirikov-Zorin, I E; Chlachidze, G; Chlebana, F; Christofek, L; Chu, M L; Chung, J Y; Chung, W H; Chung, Y S; Ciobanu, C I; Clark, A G; Coca, M; Connolly, A; Convery, M; Conway, J; Cordelli, M; Cranshaw, J; Culbertson, R; Dagenhart, D; D'Auria, S; De Cecco, S; De Jongh, F; Dell'Agnello, S; Dell'Orso, Mauro; Demers, S; Demortier, L; Deninno, M; De Pedis, D; Derwent, P F; Devlin, T; Dionisi, C; Dittmann, J R; Dominguez, A; Donati, S; D'Onofrio, M; Dorigo, T; Eddy, N; Einsweiler, K F; Engels, E; Erbacher, R D; Errede, D; Errede, S; Eusebi, R; Fan, Q; Farrington, S; Feild, R G; Fernández, J P; Ferretti, C; Field, R D; Fiori, I; Flaugher, B; Flores-Castillo, L R; Foster, G W; Franklin, M; Freeman, J; Friedman, J; Fukui, Y; Furic, I; Galeotti, S; Gallas, A; Gallinaro, M; Gao, T; García-Sciveres, M; Garfinkel, A F; Gatti, P; Gay, C; Gerdes, D W; Gerstein, E; Giagu, S; Giannetti, P; Giolo, K; Giordani, M; Giromini, P; Glagolev, V; Glenzinski, D A; Gold, M; Goldschmidt, N; Goldstein, J; Gómez, G; Goncharov, M; Gorelov, I; Goshaw, A T; Gotra, Yu; Goulianos, K; Green, C; Gresele, A; Grim, G; Grosso-Pilcher, C; Günther, M; Guillian, G; Guimarães da Costa, J; Haas, R M; Haber, C; Hahn, S R; Halkiadakis, E; Hall, C; Handa, T; Handler, R; Happacher, F; Hara, K; Hardman, A D; Harris, R M; Hartmann, F; Hatakeyama, K; Hauser, J; Heinrich, J; Heiss, A; Hennecke, M; Herndon, M; Hill, C; Höcker, A; Hoffman, K D; Hollebeek, R J; Holloway, L E; Hou, S; Huffman, B T; Hughes, R; Huston, J; Huth, J; Ikeda, H; Issever, C; Incandela, J R; Introzzi, G; Iori, M; Ivanov, A; Iwai, J; Iwata, Y; Iyutin, B; James, E; Jones, M; Joshi, U; Kambara, H; Kamon, T; Kaneko, T; Kang, J; Karagoz-Unel, M; Karr, K M; Kartal, S; Kasha, H; Kato, Y; Keaffaber, T A; Kelley, K; Kelly, M; Kennedy, R D; Kephart, R D; Khazins, D; Kikuchi, T; Kilminster, B; Kim, B J; Kim, D H; Kim, H S; Kim, M J; Kim, S B; Kim, S H; Kim, T H; Kim, Y K; Kirby, M; Kirk, M; Kirsch, L; Klimenko, S; Koehn, P; Kondo, K; Konigsberg, J; Korn, A J; Korytov, A; Kotelnikov, K A; Kovács, E; Kroll, J; Kruse, M; Krutelyov, V; Kuhlmann, S E; Kurino, K; Kuwabara, T; Kuznetsova, N; Laasanen, A T; Lai, N; Lami, S; Lammel, S; Lancaster, J; Lannon, K; Lancaster, M; Lander, R; Lath, A; Latino, G; LeCompte, T J; Le, Y; Lee, J; Lee, S W; Leonardo, N; Leone, S; Lewis, J D; Li, K; Lin, C S; Lindgren, M; Liss, T M; Liu, J B; Liu, T; Liu, Y C; Litvintsev, D O; Lobban, O; Lockyer, N S; Loginov, A; Loken, J; Loreti, M; Lucchesi, D; Lukens, P; Lusin, S; Lyons, L; Lys, J; Madrak, R; Maeshima, K; Maksimovic, P; Malferrari, L; Mangano, Michelangelo L; Manca, G; Mariotti, M; Martignon, G; Martin, M; Martin, A; Martin, V; Martínez, M; Matthews, J A J; Mazzanti, P; McFarland, K S; McIntyre, P; Menguzzato, M; Menzione, A; Merkel, P; Mesropian, C; Meyer, A; Miao, T; Miller, R; Miller, J S; Minato, H; Miscetti, S; Mishina, M; Mitselmakher, G; Miyazaki, Y; Moggi, N; Moore, E; Moore, R; Morita, Y; Moulik, T; Mulhearn, M; Mukherjee, A; Müller, T; Munar, A; Murat, P; Murgia, S; Nachtman, J; Nagaslaev, V; Nahn, S; Nakada, H; Nakano, I; Napora, R; Niell, F; Nelson, C; Nelson, T; Neu, C; Neubauer, M S; Neuberger, D; Newman-Holmes, C; Ngan, C Y P; Nigmanov, T; Niu, H; Nodulman, L; Nomerotski, A; Oh, S H; Oh, Y D; Ohmoto, T; Ohsugi, T; Oishi, R; Okusawa, T; Olsen, J; Orejudos, W; Pagliarone, C; Palmonari, F; Paoletti, R; Papadimitriou, V; Partos, D; Patrick, J; Pauletta, G; Paulini, M; Pauly, T; Paus, C; Pellett, D; Penzo, Aldo L; Pescara, L; Phillips, T J; Piacentino, G; Piedra, J; Pitts, K T; Pompos, A; Pondrom, L; Pope, G; Pratt, T; Prokoshin, F; Proudfoot, J; Ptohos, F; Pukhov, O; Punzi, G; Rademacker, J; Rakitine, A; Ratnikov, F; Ray, H; Reher, D; Reichold, A; Renton, P B; Rescigno, M; Ribon, A; Riegler, W; Rimondi, F; Ristori, L; Riveline, M; Robertson, W J; Rodrigo, T; Rolli, S; Rosenson, L; Roser, R; Rossin, R; Rott, C; Roy, A; Ruiz, A; Ryan, D; Safonov, A; Saint-Denis, R; Sakumoto, W K; Saltzberg, D; Sánchez, C; Sansoni, A; Santi, L; Sarkar, S; Sato, H; Savard, P; Savoy-Navarro, A; Schlabach, P; Schmidt, E E; Schmidt, M P; Schmitt, M; Scodellaro, L; Scott, A; Scribano, A; Sedov, A; Seidel, S; Seiya, Y; Semenov, A; Semeria, F; Shah, T; Shapiro, M D; Shepard, P F; Shibayama, T; Shimojima, M; Shochet, M J; Sidoti, A; Siegrist, J L; Sill, A; Sinervo, P; Singh, P; Slaughter, A J; Sliwa, K; Snider, F D; Snihur, R; Solodsky, A; Speer, T; Spezziga, M; Sphicas, Paris; Spinella, F; Spiropulu, M; Spiegel, L; Steele, J; Stefanini, A; Strologas, J; Strumia, F; Stuart, D; Sukhanov, A; Sumorok, K; Suzuki, T; Takano, T; Takashima, R; Takikawa, K; Tamburello, P; Tanaka, M; Tannenbaum, B; Tecchio, M; Tesarek, R J; Teng, P K; Terashi, K; Tether, S; Thom, J; Thompson, A S; Thomson, E; Thurman-Keup, R M; Tipton, P; Tkaczyk, S M; Toback, D; Tollefson, K; Tonelli, D; Tonnesmann, M; Toyoda, H; Trischuk, W; De Trocóniz, J F; Tseng, J; Tsybychev, D; Turini, N; Ukegawa, F; Unverhau, T; Vaiciulis, T; Varganov, A V; Vataga, E; Vejcik, S; Velev, G V; Veramendi, G; Vidal, R; Vila, I; Vilar, R; Volobuev, I P; Von der Mey, M; Vucinic, D; Wagner, R G; Wagner, R L; Wagner, W; Wan, Z; Wang, C; Wang, M J; Wang, S M; Ward, B; Waschke, S; Watanabe, T; Waters, D; Watts, T; Weber, M; Wenzel, H; Wester, W C; Whitehouse, B; Wicklund, A B; Wicklund, E; Wilkes, T; Williams, H H; Wilson, P; Winer, B L; Winn, D; Wolbers, S; Wolinski, D; Wolinski, J; Wolinski, S; Wolter, M; Worm, S; Wu, X; Würthwein, F; Wyss, J; Yang, U K; Yao, W; Yeh, G P; Yeh, P; Yi, K; Yoh, J K; Yosef, C; Yoshida, T; Yu, I; Yu, S; Yu, Z; Yun, J C; Zanello, L; Zanetti, A; Zetti, F; Zucchelli, S
2003-01-01
We report on a search for direct Kaluza-Klein graviton production in a data sample of 84 ${pb}^{-1}$ of \\ppb collisions at $\\sqrt{s}$ = 1.8 TeV, recorded by the Collider Detector at Fermilab. We investigate the final state of large missing transverse energy and one or two high energy jets. We compare the data with the predictions from a $3+1+n$-dimensional Kaluza-Klein scenario in which gravity becomes strong at the TeV scale. At 95% confidence level (C.L.) for $n$=2, 4, and 6 we exclude an effective Planck scale below 1.0, 0.77, and 0.71 TeV, respectively.
Lukman, D
2016-01-01
This contribution is to prove that in the Kaluza-Klein like theories the vielbeins and the spin connection fields --- as used in the spin-charge-family theory --- lead in $d=(3+1)$ space to equivalent vector (and scalar) gauge fields. The authors demonstrate this equivalence in spaces with the symmetry: $g_{\\alpha \\beta} = \\eta_{\\alpha \\beta} e$, for any scalar function $e$ of the coordinates $x^{\\alpha}$.
Kaluza-Klein gluons at 100 TeV: NLO corrections
Lillard, Benjamin; Tanedo, Philip
2016-01-01
We explore the reach of a 100 TeV proton collider to discover KK gluons in a warped extra dimension. These particles are templates for color adjoint vectors that couple dominantly to the top quark. We examine their production rate at NLO in the six-flavor m-ACOT scheme for a variety of reference models defining their coupling to quarks, largely inspired by the RS model of a warped extra dimension. In agreement with previous calculations aimed at lower energy machines, we find that the NLO corrections are typically negative, resulting in a $K$-factor of around 0.7 (depending on the model) and with a residual scale dependence on the order of $\\pm 20\\%$, greater than the variation from the scale exhibited by the na\\"{i}ve LO estimate.
Energy Technology Data Exchange (ETDEWEB)
Savina, M. V., E-mail: savina@cern.ch [Joint Institute for Nuclear Research (Russian Federation)
2015-06-15
A survey of the results of the Compact Muon Solenoid (CMS) experiment that concern searches for massive Kaluza-Klein graviton excitations and microscopic black holes, quantum black holes, and string balls within models of low-energy multidimensional gravity is presented on behalf of the CMS Collaboration. The analysis in question is performed on the basis of a complete sample of data accumulated for proton-proton collisions at the c.m. energies of 7 and 8 TeV at the Large Hadron Collider (LHC) over the period spanning 2010 and 2012.
Open and Closed World Models in Kaluza-Klein-Theory with Variables G and Λ
Nashed, Gamal G. L.
2014-11-01
The field equation of higher dimensions theory, have been applied in the area of cosmology. The resulting differential equations are solved for open and closed. We derive a relation between the Einstein constant G( t) and the cosmological constant Λ( t) from the conservation law T μ ν ; ν =0. We give a specific form of Λ( t) to solve the non-linear differential equations. Some cosmological parameters are calculated and some relevant cosmological problems are discussed.
Energy Technology Data Exchange (ETDEWEB)
Lukman, Dragan; Mankoc Borstnik, Norma Susana [University of Ljubljana, Department of Physics, FMF, Ljubljana (Slovenia)
2017-04-15
It is shown that in the spin-charge-family theory (Mankoc Borstnik in arXiv:1607.01618v2, 2016, Phys Rev D 91:065004. arxiv:1409.7791, 2015, J Mod Phys 6:2244. doi:10.4236/jmp.2015.615230. arXiv: 1409.4981, 2015, J Mod Phys 4:823. doi:10.4236/jmp.2013.46113. arxiv:1312.1542, 2013, arxiv:1409.4981, 2014) as well as in all the Kaluza-Klein like theories (Blagojevic in Gravitation and gauge symmetries, IoP Publishing, Bristol, 2002, An introduction to Kaluza-Klein theories, World Scientific, Singapore, 1983), vielbeins and spin connections manifest in d = (3+1) space equivalent vector gauge fields, when space with d ≥ 5 has a large enough symmetry. The authors demonstrate this equivalence in spaces with the symmetry of the metric tensor in the space out of d = (3+1)-g{sup στ} = η{sup στ} f{sup 2} - for any scalar function f of the coordinates x{sup σ}, where x{sup σ} denotes the coordinates of space out of d = (3+1). Also the connection between vielbeins and scalar gauge fields in d = (3+1) (offering the explanation for the Higgs scalar) is discussed. (orig.)
Finite temperature Casimir effect in spacetime with extra compactified dimensions
Energy Technology Data Exchange (ETDEWEB)
Teo, L.P. [Faculty of Information Technology, Multimedia University, Jalan Multimedia, Cyberjaya 63100, Selangor Darul Ehsan (Malaysia)], E-mail: lpteo@mmu.edu.my
2009-02-16
In this Letter, we derive the explicit exact formulas for the finite temperature Casimir force acting on a pair of parallel plates in the presence of extra compactified dimensions within the framework of Kaluza-Klein theory. Using the piston analysis, we show that at any temperature, the Casimir force due to massless scalar field with Dirichlet boundary conditions on the plates is always attractive and the effect of extra dimensions becomes stronger when the size or number of the extra dimensions increases. These properties are not affected by the explicit geometry and topology of the Kaluza-Klein space.
Current LHC constraints on minimal universal extra dimensions
Deutschmann, Nicolas; Flacke, Thomas; Kim, Jong Soo
2017-08-01
In this letter, we present LHC limits on the minimal universal extra dimension (MUED) model from LHC Run 1 data and current limits from searches of the ongoing Run 2. Typical collider signals of the Kaluza-Klein (KK) states mimic generic degenerate supersymmetry (SUSY) missing transverse momentum signatures since the KK particles cascade decay into jets, leptons and the lightest KK particle which is stable due to KK parity and evades detection. We test the parameter space against a large number of supersymmetry based missing energy searches implemented in the public code CheckMATE. We demonstrate the complementarity of employing various searches which target a large number of final state signatures, and we derive the most up to date limits on the MUED parameter space from 13 TeV SUSY searches.
Probing Extra Dimensions with Neutrino Oscillations
Energy Technology Data Exchange (ETDEWEB)
Machado, P.A.N. [Instituto de Fisica, Universidade de Sao Paulo, C. P. 66.318, 05315-970 Sao Paulo (Brazil); Nunokawa, H. [Departamento de Fisica, Pontificia Universidade Catolica do Rio de Janeiro, C. P. 38071, 22452-970 Rio de Janeiro (Brazil); Zukanovich Funchal, R., E-mail: zukanov@fma.if.usp.br [Instituto de Fisica, Universidade de Sao Paulo, C. P. 66.318, 05315-970 Sao Paulo (Brazil)
2011-08-15
We consider a model where sterile neutrinos can propagate in a large compactified extra dimension (a) giving rise to Kaluza-Klein (KK) modes and the Standard Model left-handed neutrinos are confined to a 4-dimensional spacetime brane. The KK modes mix with the standard neutrinos modifying their oscillation pattern. We examine current experiments in this framework obtaining stringent limits on a.
Extra dimensions and violations of Lorentz symmetry
Overduin, James M
2016-01-01
We use experimental limits on Lorentz violation to obtain new constraints on Kaluza-Klein-type theories in which the extra dimensions may be large but do not necessarily have units of length. The associated variation in fundamental quantities such as rest mass must occur slowly, on cosmological scales.
Suppressing Lepton Flavour Violation in a Soft-Wall Extra Dimension
Atkins, Michael
2010-01-01
A soft-wall warped extra dimension allows one to relax the tight constraints imposed by electroweak data in conventional Randall-Sundrum models. We investigate a setup, where the lepton flavour structure of the Standard Model is realised by split fermion locations. Bulk fermions with general locations are not analytically tractable in a soft-wall background, so we follow a numerical approach to perform the Kaluza-Klein reduction. Lepton flavour violation is induced by the exchange of Kaluza-Klein gauge bosons. We find that rates for processes such as muon-electron conversion are significantly reduced compared to hard-wall models, allowing for a Kaluza-Klein scale as low as 2 TeV. Accommodating small neutrino masses forces one to introduce a large hierarchy of scales into the model, making pressing the question of a suitable stabilisation mechanism.
Higgs Pair Production in Models with Universal Extra Dimensions
de Sandes, Hiroshi
2007-01-01
In this letter we study the process of gluon fusion into a pair of Higgs bosons in a model with one universal extra dimension. We find that the contributions from the extra top quark Kaluza-Klein excitations lead to a Higgs pair production cross section that can be significantly altered compared to the Standard Model value for small values of the compactification scale.
Casimir Effect at Finite Temperature in the Presence of Compactified Universal Extra Dimensions
Institute of Scientific and Technical Information of China (English)
CHENG Hong-Bo
2005-01-01
@@ We analyse the Casimir effect for parallel plates atfinite temperature in the presence of compactified universal extra dimensions and analytically show the thermal corrections to the effect in detail. The Casimir effect for different sizes of universal extra dimensions is investigated to test the five-dimensional Kaluza-Klein theory.
Pasqua, Antonio; Chattopadhyay, Surajit; Assaf, Khudhair A.; Salako, Ines G.
2016-06-01
In this paper, we study the properties of the Holographic Dark Energy (HDE) model in the context of Kaluza-Klein (KK) cosmology with infrared cut-off given by the recently proposed by Granda-Oliveros cut-off, which contains a term proportional to the time derivative of the Hubble parameter and one proportional to the Hubble parameter squared. Moreover, this cut-off is characterized by two free parameters which are the proportional constants of the two terms of the cut-off. We derive the expression of the Equation of State (EoS) parameter ωD and of the deceleration parameter q for both non-interacting and interacting Dark Sectors and in the limiting case of a flat Dark Dominated Universe. Moreover, we study the squared speed of the sound vs2 and the statefinder diagnostic \\{r,s\\} in order to understand the cosmological properties of the model considered. We also develop a correspondence between the model considered and three scalar field models: the tachyon, the k-essence and the quintessence ones.
Phenomenology of universal extra dimensions
Energy Technology Data Exchange (ETDEWEB)
Kong, Kyoungchul; Matchev, Konstantin T.; /Florida U.
2006-10-01
In this proceeding, the phenomenology of Universal Extra Dimensions (UED), in which all the Standard Model fields propagate, is explored. We focus on models with one universal extra dimension, compactified on an S{sub 1}/Z{sub 2} orbifold. We revisit calculations of Kaluza-Klein (KK) dark matter without an assumption of the KK mass degeneracy including all possible coannihilations. We then contrast the experimental signatures of low energy supersymmetry and UED.
Probing large extra dimensions with IceCube
Energy Technology Data Exchange (ETDEWEB)
Esmaili, Arman [Institute of Convergence Fundamental Studies and School of Liberal Arts, Seoul National University of Science and Technology, Seoul 139-743 (Korea, Republic of); Peres, O.L.G.; Tabrizi, Zahra, E-mail: arman@ipm.ir, E-mail: orlando@ifi.unicamp.br, E-mail: tabrizi.physics@ipm.ir [Instituto de Física Gleb Wataghin - UNICAMP, 13083-859, Campinas, SP (Brazil)
2014-12-01
In models with Large Extra Dimensions the smallness of neutrino masses can be naturally explained by introducing gauge singlet fermions which propagate in the bulk. The Kaluza-Klein modes of these fermions appear as towers of sterile neutrino states on the brane. We study the phenomenological consequences of this picture for the high energy atmospheric neutrinos. For this purpose we construct a detailed equivalence between a model with large extra dimensions and a (3+n) scenario consisting of three active and n extra sterile neutrino states, which provides a clear intuitive understanding of Kaluza-Klein modes. Finally, we analyze the collected data of high energy atmospheric neutrinos by IceCube experiment and obtain bounds on the radius of extra dimensions.
Dark Matter and Collider Phenomenology of Universal Extra Dimensions
Hooper, D; Hooper, Dan; Profumo, Stefano
2007-01-01
We review the phenomenology of models with flat, compactified extra dimensions where all of the Standard Model fields are allowed to propagate in the bulk, known as Universal Extra Dimensions (UED). UED make for an interesting TeV-scale physics scenario, featuring a tower of Kaluza-Klein (KK) states approximately degenerate in mass at the scale set by the inverse size of the compactification radius. KK parity, the four-dimensional remnant of momentum conservation in the extra dimensions, implies two basic consequences: (1) contributions to Standard Model observables arise only at loop level, and KK states can only be pair-produced at colliders, and (2) the lightest KK particle (LKP) is stable, providing a suitable particle dark matter candidate. After a theoretical overview on extra dimensional models, and on UED in particular, we introduce the model particle spectrum and the constraints from precision electroweak tests and current colliders data. We then give a detailed overview of the LKP dark matter phenom...
Search for Extra Dimensions with the CMS Detector
Shmatov, Sergei
2008-01-01
Multidimensional theories at TeV energies, as given in the brane world scenarios with large or compact extra spatial dimensions (ED), are discussed. One interesting feature of recent ED models is the rich low-energy phenomenology that originates from the Kaluza-Klein spectrum of various particles propagating in ED. A series of searches is addressed in the CMS experiment with different signatures.
Higher Curvature Gravity in TeV-Scale Extra Dimensions
Energy Technology Data Exchange (ETDEWEB)
Rizzo, Thomas G.
2006-03-31
We begin a general exploration of the phenomenology of TeV-scale extra-dimensional models with gravitational actions that contain higher curvature terms. In particular, we examine how the classic collider signatures of the models of Arkani-Hamed, Dimopoulos and Dvali (missing energy and new dimension-8 contact interactions) and of Randall and Sundrum (TeV-scale graviton Kaluza-Klein resonances) are altered by these modifications to the usual Einstein-Hilbert action. We find that not only are the detailed signatures for these gravitationally induced processes altered but new contributions are found to arise due to the existence of additional scalar Kaluza-Klein states in the spectrum.
Energy Technology Data Exchange (ETDEWEB)
Rizzo, Thomas G.
1999-06-03
The elementary particles of the Standard Model may live in more than 3+1 dimensions. We study the consequences of large compactified dimensions on scattering and decay observables at high-energy colliders. Our analysis includes global fits to electroweak precision data, indirect tests at high-energy electron-positron colliders (LEP2 and NLC), and direct probes of the Kaluza-Klein resonances at hadron colliders (Tevatron and LHC). The present limits depend sensitively on the Higgs sector, both the mass of the Higgs boson and how many dimensions it feels. If the Higgs boson is trapped on a 3+1 dimensional wall with the fermions, large Higgs masses (up to 500 GeV) and relatively light Kaluza-Klein mass scales (less than 4 TeV) can provide a good fit to precision data. That is, a light Higgs boson is not necessary to fit the electroweak precision data, as it is in the Standard Model. If the Higgs boson propagates in higher dimensions, precision data prefer a light Higgs boson (less than 260 GeV), and a higher compactification scale (greater than 3.8 TeV). Future colliders can probe much larger scales. For example, a 1.5 TeV electron-positron linear collider can indirectly discover Kaluza-Klein excitations up to 31 TeV if 500 fb{sup {minus}1} integrated luminosity is obtained.
Bauman, Sky
2008-01-01
In a previous companion paper [arXiv:0712.3532], we proposed two new regulators for quantum field theories in spacetimes with compactified extra dimensions. Unlike most other regulators which have been used in the extra-dimension literature, these regulators are specifically designed to respect the original higher-dimensional Lorentz and gauge symmetries that exist prior to compactification, and not merely the four-dimensional symmetries which remain afterward. In this paper, we use these regulators in order to develop a method for extracting ultraviolet-finite results from one-loop calculations. This method also allows us to derive Wilsonian effective field theories for Kaluza-Klein modes at different energy scales. Our method operates by ensuring that divergent corrections to parameters describing the physics of the excited Kaluza-Klein modes are absorbed into the corresponding parameters for zero modes, thereby eliminating the need to introduce independent counterterms for parameters characterizing differe...
Search for large extra dimensions in the mono-photon final state at $\\sqrt{s}$ = 1.96 TeV
Abazov, V; Abolins, M; Acharya, B S; Adams, M; Adams, T; Aguiló, E; Ahn, S H; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Anastasoaie, M; Ancu, L S; Andeen, T; Anderson, S; Andrieu, B; Anzelc, M S; Aoki, M; Arnoud, Y; Arov, M; Arthaud, M; Askew, A; sman, B; Assis-Jesus, A C S; Atramentov, O; Avila, C; Ay, C; Badaud, F; Baden, AA; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, P; Banerjee, S; Barberis, E; Barfuss, A F; Bargassa, P; Baringer, P; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Beale, S; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Bellavance, A; Benítez, J A; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Biscarat, C; Blazey, G; Blekman, F; Blessing, S; Bloch, D; Bloom, K; Böhnlein, A; Boline, D; Bolton, T A; Borissov, G; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Brown, D; Buchanan, N J; Buchholz, D; Bühler, M; Büscher, V; Bunichev, V; Burdin, S; Burke, S; Burnett, T H; Buszello, C P; Butler, J M; Calfayan, P; Calvet, S; Cammin, J; Carrera, E; Carvalho, W; Casey, B C K; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K; Chan, K M; Chandra, A; Charles, F; Cheu, E; Chevallier, F; Cho, D K; Choi, S; Choudhary, B; Christofek, L; Christoudias, T; Cihangir, S; Claes, D; Coadou, Y; Cooke, M; Cooper, W E; Corcoran, M; Couderc, F; Cousinou, M C; Crepe-Renaudin, S; Cutts, D; Cwiok, M; Da Motta, H; Das, A; Davies, G; De, K; De Jong, S J; De La Cruz-Burelo, E; De Oliveira Martins, C; Degenhardt, J D; Dliot, F; Demarteau, M; Demina, R; Denisov, D; Denisov, S P; Desai, S; Diehl, e H T; Diesburg, M; Dominguez, A; Dong, H; Dudko, L V; Duflot, L; Dugad, S R; Duggan, D; Duperrin, A; Dyer, J; Dyshkant, A; Eads, M; Edmunds, D; Ellison, J; Elvira, V D; Enari, Y; Eno, S; Ermolov, P; Evans, H; Evdokimov, A; Evdokimov, V N; Ferapontov, A V; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fortner, M; Fox, H; Fu, S; Fuess, S; Gadfort, T; Galea, C F; Gallas, E; García, C; García-Bellido, A; Gavrilov, V; Gay, P; Geist, W; Gel, D; Gerber, e C E; Gershtein, Yu; Gillberg, D; Ginther, G; Gollub, N; Gmez, B; Goussiou, A; Grannis, P D; Greenlee, o H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, P; Grivaz, J F; Grohsjean, A; Grünendahl, S; Grünewald, M W; Guo, F; Guo, J; Gutíerrez, G; Gutíerrez, P; Haas, A; Hadley, N J; Haefner, P; Hagopian, S; Haley, J; Hall, I; Hall, R E; Han, L; Harder, K; Harel, A; Harrington, R; Hauptman, J M; Hauser, R; Hays, J; Hebbeker, T; Hedin, D; Hegeman, J G; Heinmiller, J M; Heinson, A P; Heintz, U; Hensel, C; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hobbs, J D; Hoeneisen, B; Hoeth, H; Hohlfeld, M; Hong, S J; Hossain, S; Houben, P; Hu, Y; Hubacek, Z; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jakobs, K; Jarvis, C; Jesik, e R; Johns, K; Johnson, C; Johnson, M; Jonckheere, A; Jonsson, P; Juste, A; Kajfasz, E; Kalinin, A M; Kalk, J M; Kappler, S; Karmanov, D; Kasper, P A; Katsanos, I; Kau, D; Kaushik, V; Kehoe, R; Kermiche, S; Khalatyan, N; Khanov, A; Kharchilava, A; Kharzheev, Yu M; Khatidze, D; Kim, T J; Kirby, M H; Kirsch, M; Klima, B; Kohli, J M; Konrath, J P; Korablev, V M; Kozelov, A V; Kraus, J; Krop, D; Kühl, T; Kumar, A; Kupco, A; Kura, T; Kvita, J; Lacroix, F; Lam, cD; Lammers, S; Landsberg, G; Lebrun, P; Lee, W M; Leflat, A; Lellouch, J; Lévêque, J; Li, J; Li, L; Li, Q Z; Lietti, S M; Lima, J G R; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Y; Liu, Z; Lobodenko, A; Lokajícek, M; Love, P; Lubatti, H J; Luna, R; Lyon, A L; Maciel, A K A; Mackin, D; Madaras, R J; Mättig, P; Magass, C; Magerkurth, A; Mal, P K; Malbouisson, H B; Malik, S; Malyshev, V L; Mao, H S; Maravin, Y; Martin, B; McCarthy, R; Melnitchouk, A; Mendoza, L; Mercadante, P G; Merkin, M; Merritt, K W; Meyer, A; Meyer, J; Millet, T; Mitrevski, J; Molina, J; Mommsen, R K; Mondal, N K; Moore, R W; Moulik, T; Muanza, G S; Mulders, M; Mulhearn, M; Mundal, O; Mundim, L; Nagy, E; Naimuddin, M; Narain, M; Naumann, N A; Neal, H A; Negret, J P; Neustroev, P; Nilsen, H; Nogima, H; Novaes, S F; Nunnemann, T; O'Dell, V; O'Neil, D C; Obrant, G; Ochando, C; Onoprienko, D; Oshima, N; Osman, N; Osta, J; Otec, R; Oteroy-Garzon, G J; Owen, M; Padley, P; Pangilinan, M; Parashar, N; Park, S J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Pawloski, G; Penning, B; Perfilov, M; Peters, K; Peters, Y; Pétroff, P; Petteni, M; Piegaia, R; Piper, J; Pleier, M A; Podesta-Lerma, P L M; Podstavkov, e V M; Pogorelov, Y; Pol, M E; Polozov, P; Pope, B G; Popov, A V; Potter, C; Prado da Silva, W L; Prosper, H B; Protopopescu, S; Qian, J; Quadt, A; Quinn, B; Rakitine, A; Rangel, M S; Ranjan, K; Ratoff, P N; Renkel, P; Reucroft, S; Rich, P; Rieger, J; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F; Robinson, S; Rodrigues, R F; Rominsky, M; Royon, C; Rubinov, P; Ruchti, R; Safronov, G; Sajot, G; Sánchez-Hernández, A; Sanders, M P; Santoro, A; Savage, G; Sawyer, L; Scanlon, T; Schaile, A D; Schamberger, R D; Scheglov, Y; Schellman, H; Schliephake, T; Schwanenberger, C; Schwartzman, A; Schwienhorst, R; Sekaric, J; Severini, H; Shabalina, E; Shamim, M; Shary, V; Shchukin, A A; Shivpuri, R K; Siccardi, V; Simák, V; Sirotenko, V; Skubic, P; Slattery, P; Smirnov, D; Snow, G R; Snow, J; Snyder, S; Söldner-Rembold, S; Sonnenschein, L; Sopczak, A; Sosebee, M; Soustruznik, K; Spurlock, B; Stark, J; Steele, J; Stolin, V; Stoyanova, D A; Strandberg, J; Strandberg, S; Strang, M A; Strauss, E; Strauss, M; Ströhmer, R; Strom, D; Stutte, L; Sumowidagdo, S; Svoisky, P; Sznajder, A; Tamburello, P; Tanasijczuk, A; Taylor, W; Temple, J; Tiller, B; Tissandier, F; Titov, M; Tokmenin, V V; Toole, T; Torchiani, I; Trefzger, T; Tsybychev, D; Tuchming, B; Tully, C; Tuts, P M; Unalan, R; Uvarov, L; Uvarov, S; Uzunyan, S; Vachon, B; vanden Berg, P J; Van Kooten, R; Van Leeuwen, W M; Varelas, N; Varnes, E W; Vasilyev, I A; Vaupel, M; Verdier, P; Vertogradov, L S; Verzocchi, M; Villeneuve-Séguier, F; Vint, P; Vokac, P; Von Törne, E; Voutilainen, M; Wagner, R; Wahl, H D; Wang, L; Wang, M H L S; Warchol, J; Watts, G; Wayne, M; Weber, G; Weber, M; Welty-Rieger, L; Wenger, A; Wermes, N; Wetstein, M; White, A; Wicke, D; Wilson, G W; Wimpenny, S J; Wobisch, M; Wood, D R; Wyatt, T R; Xie, Y; Yacoob, S; Yamada, R; Yan, M; Yasuda, T; Yatsunenko, Y A; Yip, K; Yoo, H D; Youn, S W; Yu, J; Zatserklyaniy, A; Zeitnitz, C; Zhao, T; Zhou, B; Zhu, J; Zielinski, M; Zieminska, D; Zieminski, A; Zivkovic, L; Zutshi, V; Zverev, E G
2008-01-01
We report on a search for large extra dimensions in a data sample of approximately 1 fb^{-1} of p pbar collisions at $\\sqrt{s}$ = 1.96 TeV. We investigate Kaluza-Klein graviton production with a photon and missing transverse energy in the final state. At the 95% C.L. we set limits on the fundamental mass scale M_{D} from 884 GeV to 778 GeV for 2 to 8 extra dimensions.
Abazov, V M; Abbott, B; Abolins, M; Acharya, B S; Adams, M; Adams, T; Aguilo, E; Ahn, S H; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Anastasoaie, M; Ancu, L S; Andeen, T; Anderson, S; Andrieu, B; Anzelc, M S; Aoki, M; Arnoud, Y; Arov, M; Arthaud, M; Askew, A; Asman, B; Assis Jesus, A C S; Atramentov, O; Avila, C; Ay, C; Badaud, F; Baden, A; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, P; Banerjee, S; Barberis, E; Barfuss, A-F; Bargassa, P; Baringer, P; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Beale, S; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Bellavance, A; Benitez, J A; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Biscarat, C; Blazey, G; Blekman, F; Blessing, S; Bloch, D; Bloom, K; Boehnlein, A; Boline, D; Bolton, T A; Borissov, G; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Brown, D; Buchanan, N J; Buchholz, D; Buehler, M; Buescher, V; Bunichev, V; Burdin, S; Burke, S; Burnett, T H; Buszello, C P; Butler, J M; Calfayan, P; Calvet, S; Cammin, J; Carrera, E; Carvalho, W; Casey, B C K; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K; Chan, K M; Chandra, A; Charles, F; Cheu, E; Chevallier, F; Cho, D K; Choi, S; Choudhary, B; Christofek, L; Christoudias, T; Cihangir, S; Claes, D; Coadou, Y; Cooke, M; Cooper, W E; Corcoran, M; Couderc, F; Cousinou, M-C; Crépé-Renaudin, S; Cutts, D; Cwiok, M; da Motta, H; Das, A; Davies, G; De, K; de Jong, S J; De La Cruz-Burelo, E; De Oliveira Martins, C; Degenhardt, J D; Déliot, F; Demarteau, M; Demina, R; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Dominguez, A; Dong, H; Dudko, L V; Duflot, L; Dugad, S R; Duggan, D; Duperrin, A; Dyer, J; Dyshkant, A; Eads, M; Edmunds, D; Ellison, J; Elvira, V D; Enari, Y; Eno, S; Ermolov, P; Evans, H; Evdokimov, A; Evdokimov, V N; Ferapontov, A V; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fortner, M; Fox, H; Fu, S; Fuess, S; Gadfort, T; Galea, C F; Gallas, E; Garcia, C; Garcia-Bellido, A; Gavrilov, V; Gay, P; Geist, W; Gelé, D; Gerber, C E; Gershtein, Y; Gillberg, D; Ginther, G; Gollub, N; Gómez, B; Goussiou, A; Grannis, P D; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, Ph; Grivaz, J-F; Grohsjean, A; Grünendahl, S; Grünewald, M W; Guo, F; Guo, J; Gutierrez, G; Gutierrez, P; Haas, A; Hadley, N J; Haefner, P; Hagopian, S; Haley, J; Hall, I; Hall, R E; Han, L; Harder, K; Harel, A; Harrington, R; Hauptman, J M; Hauser, R; Hays, J; Hebbeker, T; Hedin, D; Hegeman, J G; Heinmiller, J M; Heinson, A P; Heintz, U; Hensel, C; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hobbs, J D; Hoeneisen, B; Hoeth, H; Hohlfeld, M; Hong, S J; Hossain, S; Houben, P; Hu, Y; Hubacek, Z; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jakobs, K; Jarvis, C; Jesik, R; Johns, K; Johnson, C; Johnson, M; Jonckheere, A; Jonsson, P; Juste, A; Kajfasz, E; Kalinin, A M; Kalk, J M; Kappler, S; Karmanov, D; Kasper, P A; Katsanos, I; Kau, D; Kaushik, V; Kehoe, R; Kermiche, S; Khalatyan, N; Khanov, A; Kharchilava, A; Kharzheev, Y M; Khatidze, D; Kim, T J; Kirby, M H; Kirsch, M; Klima, B; Kohli, J M; Konrath, J-P; Korablev, V M; Kozelov, A V; Kraus, J; Krop, D; Kuhl, T; Kumar, A; Kupco, A; Kurca, T; Kvita, J; Lacroix, F; Lam, D; Lammers, S; Landsberg, G; Lebrun, P; Lee, W M; Leflat, A; Lellouch, J; Leveque, J; Li, J; Li, L; Li, Q Z; Lietti, S M; Lima, J G R; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Y; Liu, Z; Lobodenko, A; Lokajicek, M; Love, P; Lubatti, H J; Luna, R; Lyon, A L; Maciel, A K A; Mackin, D; Madaras, R J; Mättig, P; Magass, C; Magerkurth, A; Mal, P K; Malbouisson, H B; Malik, S; Malyshev, V L; Mao, H S; Maravin, Y; Martin, B; McCarthy, R; Melnitchouk, A; Mendoza, L; Mercadante, P G; Merkin, M; Merritt, K W; Meyer, A; Meyer, J; Millet, T; Mitrevski, J; Molina, J; Mommsen, R K; Mondal, N K; Moore, R W; Moulik, T; Muanza, G S; Mulders, M; Mulhearn, M; Mundal, O; Mundim, L; Nagy, E; Naimuddin, M; Narain, M; Naumann, N A; Neal, H A; Negret, J P; Neustroev, P; Nilsen, H; Nogima, H; Novaes, S F; Nunnemann, T; O'Dell, V; O'Neil, D C; Obrant, G; Ochando, C; Onoprienko, D; Oshima, N; Osman, N; Osta, J; Otec, R; Otero y Garzón, G J; Owen, M; Padley, P; Pangilinan, M; Parashar, N; Park, S-J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Pawloski, G; Penning, B; Perfilov, M; Peters, K; Peters, Y; Pétroff, P; Petteni, M; Piegaia, R; Piper, J; Pleier, M-A; Podesta-Lerma, P L M; Podstavkov, V M; Pogorelov, Y; Pol, M-E; Polozov, P; Pope, B G; Popov, A V; Potter, C; Prado da Silva, W L; Prosper, H B; Protopopescu, S; Qian, J; Quadt, A; Quinn, B; Rakitine, A; Rangel, M S; Ranjan, K; Ratoff, P N; Renkel, P; Reucroft, S; Rich, P; Rieger, J; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F; Robinson, S; Rodrigues, R F; Rominsky, M; Royon, C; Rubinov, P; Ruchti, R; Safronov, G; Sajot, G; Sánchez-Hernández, A; Sanders, M P; Santoro, A; Savage, G; Sawyer, L; Scanlon, T; Schaile, D; Schamberger, R D; Scheglov, Y; Schellman, H; Schliephake, T; Schwanenberger, C; Schwartzman, A; Schwienhorst, R; Sekaric, J; Severini, H; Shabalina, E; Shamim, M; Shary, V; Shchukin, A A; Shivpuri, R K; Siccardi, V; Simak, V; Sirotenko, V; Skubic, P; Slattery, P; Smirnov, D; Snow, G R; Snow, J; Snyder, S; Söldner-Rembold, S; Sonnenschein, L; Sopczak, A; Sosebee, M; Soustruznik, K; Spurlock, B; Stark, J; Steele, J; Stolin, V; Stoyanova, D A; Strandberg, J; Strandberg, S; Strang, M A; Strauss, E; Strauss, M; Ströhmer, R; Strom, D; Stutte, L; Sumowidagdo, S; Svoisky, P; Sznajder, A; Tamburello, P; Tanasijczuk, A; Taylor, W; Temple, J; Tiller, B; Tissandier, F; Titov, M; Tokmenin, V V; Toole, T; Torchiani, I; Trefzger, T; Tsybychev, D; Tuchming, B; Tully, C; Tuts, P M; Unalan, R; Uvarov, L; Uvarov, S; Uzunyan, S; Vachon, B; van den Berg, P J; Van Kooten, R; van Leeuwen, W M; Varelas, N; Varnes, E W; Vasilyev, I A; Vaupel, M; Verdier, P; Vertogradov, L S; Verzocchi, M; Villeneuve-Seguier, F; Vint, P; Vokac, P; Von Toerne, E; Voutilainen, M; Wagner, R; Wahl, H D; Wang, L; Wang, M H L S; Warchol, J; Watts, G; Wayne, M; Weber, G; Weber, M; Welty-Rieger, L; Wenger, A; Wermes, N; Wetstein, M; White, A; Wicke, D; Wilson, G W; Wimpenny, S J; Wobisch, M; Wood, D R; Wyatt, T R; Xie, Y; Yacoob, S; Yamada, R; Yan, M; Yasuda, T; Yatsunenko, Y A; Yip, K; Yoo, H D; Youn, S W; Yu, J; Zatserklyaniy, A; Zeitnitz, C; Zhao, T; Zhou, B; Zhu, J; Zielinski, M; Zieminska, D; Zieminski, A; Zivkovic, L; Zutshi, V; Zverev, E G
2008-07-04
We report on a search for large extra dimensions in a data sample of approximately 1 fb(-1) of pp[over] collisions at sqrt s=1.96 TeV. We investigate Kaluza-Klein graviton production with a photon and missing transverse energy in the final state. At the 95% C.L. we set limits on the fundamental mass scale M(D) from 884 to 778 GeV for two to eight extra dimensions.
Bounds on universal extra dimension from LHC run I and II data
Choudhury, Debajyoti; Ghosh, Kirtiman
2016-12-01
We discuss the collider bounds on minimal Universal Extra Dimension (mUED) model from LHC Run-I and II data. The phenomenology of mUED is determined by only two parameters namely, the compactification scale (R-1) of the extra dimension and cutoff scale (Λ) of the theory. The characteristic feature of mUED is the occurrence of nearly degenerate mass spectrum for the Kaluza-Klein (KK) particles and hence, soft leptons, soft jets at the collider experiments. The degree of degeneracy of KK-mass spectrum crucially depends on Λ. The strongest direct bound on R-1 (∼ 950GeV for large Λ) arises from a search for a pair of soft dimuons at the Large Hadron Collider (LHC) experiment with 8 TeV center-of-mass energy and 20 fb-1 integrated luminosity. However, for small Λ and hence, small splitting within the first KK-level, the bounds from the dimuon channel are rather weak. On the other hand, the discovery of 126 GeV Higgs boson demands small Λ to prevent the scalar potential form being unbounded from below. We discuss LHC monojet searches as a probe of low Λ region of mUED parameter space. We also compute bounds on the mUED parameter space from 13 TeV multijets results.
Bounds on Universal Extra Dimension from LHC Run I and II data
Choudhury, Debajyoti
2016-01-01
We discuss the collider bounds on minimal Universal Extra Dimension (mUED) model from LHC Run-I and II data. The phenomenology of mUED is determined by only two parameters namely, the compactification scale ($R^{-1}$) of the extra dimension and cutoff scale ($\\Lambda$) of the theory. The characteristic feature of mUED is the occurrence of nearly degenerate mass spectrum for the Kaluza-Klein (KK) particles and hence, soft leptons, soft jets at the collider experiments. The degree of degeneracy of KK-mass spectrum crucially depends on $\\Lambda$. The strongest direct bound on $R^{-1}$ ($\\sim $950 GeV for large $\\Lambda$) arises from a search for a pair of soft dimuons at the Large Hadron Collider (LHC) experiment with 8 TeV center-of-mass energy and $20~{\\rm fb}^{-1}$ integrated luminosity. However, for small $\\Lambda$ and hence, small splitting within the first KK-level, the bounds from the dimuon channel is rather weak. On the other hand, the discovery of 126 GeV Higgs boson demands small $\\Lambda$ to prevent ...
Looking For TeV-Scale Strings and Extra-Dimensions
Accomando, E; Benakli, Karim
2000-01-01
In contrast to the old heterotic string case, the (weakly coupled) type I brane framework allows to have all, part or none of the standard model gauge group factors propagating in large extra--dimensions of TeV$^{-1}$ size. We investigate the main experimental signatures of these possibilities, related to the production of Kaluza-Klein excitations of gluons and electroweak gauge bosons. A discovery through direct observation of resonances is possible only for compactification scales below 6 TeV. However effects due to exchange of virtual Kaluza-Klein excitations could be observed for higher scales. We find that LHC can probe compactification scales as high as 20 TeV for excitations of gluons and 8-15 TeV for excitations of electroweak gauge bosons. Finally, in the case where no gauge boson feels the extra-dimension, we find that effective contact interactions due to massive string mode oscillations dominate those due to the exchange of Kaluza-Klein excitations of gravitons and could be used to obtain bounds o...
The world in eleven dimensions a tribute to Oskar Klein
Duff, Michael J
2001-01-01
Current attempts to find a unified theory that would reconcile Einstein's General Relativity and Quantum Mechanics, and explain all known physical phenomena, invoke the Kaluza-Klein idea of extra spacetime dimensions. The best candidate is M-theory, which lives in eleven dimensions, the maximum allowed by supersymmetry of the elementary particles. We give a non-technical account. An Appendix provides an updated version of Edwin A. Abbott's 1884 satire {\\it Flatland: A Romance of Many Dimensions}. Entitled {\\it Flatland, Modulo 8}, it describes the adventures of a superstring theorist, A. Square, who inhabits a ten-dimensional world and is initially reluctant to accept the existence of an eleventh dimension.
Chern-Simons gravity in four dimensions
Energy Technology Data Exchange (ETDEWEB)
Morales, Ivan; Neves, Bruno; Piguet, Olivier [Universidade Federal de Vicosa (UFV), Departamento de Fisica, Vicosa, MG (Brazil); Oporto, Zui [Universidade Federal de Vicosa (UFV), Departamento de Fisica, Vicosa, MG (Brazil); Universidad Mayor de San Andres, Carrera de Fisica, La Paz (Bolivia, Plurinational State of)
2017-02-15
Five-dimensional Chern-Simons theory with (anti-)de Sitter SO(1,5) or SO(2,4) gauge invariance presents an alternative to general relativity with cosmological constant. We consider the zero modes of its Kaluza-Klein compactification to four dimensions. Solutions with vanishing torsion are obtained in the cases of a spherically symmetric 3-space and of a homogeneous and isotropic 3-space, which reproduce the Schwarzshild-de Sitter and ΛCDM cosmological solutions of general relativity. We also check that vanishing torsion is a stable feature of the solutions. (orig.)
Counting Extra Dimensions Magnetic Cherenkov Radiation from High Energy Neutrinos
Domokos, Gabor K; Kövesi-Domokos, S; Erdas, Andrea
2003-01-01
In theories which require a space of dimension d > 4, there is a natural mechanism of suppressing neutrino masses: while Standard Model fields are confined to a 3-brane, right handed neutrinos live in the bulk. Due to Kaluza-Klein excitations, the effective magnetic moments of neutrinos are enhanced. The effective magnetic moment is a monotonically growing function of the energy of the neutrino: consequently, high energy neutrinos can emit observable amounts of magnetic Cherenkov radiation. By observing the energy dependence of the magnetic Cherenkov radiation, one may be able to determine the number of compactified dimensions.
On aether terms in a space-time with a compact extra dimension
Mariz, T; Petrov, A Yu
2016-01-01
In this paper, for the CPT-even and CPT-odd extensions of the QED, we explicitly obtain the aether-like corrections for the electromagnetic field in the case when the space-time involves an extra compact spatial dimension besides of usual four dimensions. Our methodology is based on an explicit summation over the Kaluza-Klein tower of fields which is no more difficult than the finite-temperature calculations. The quantum corrections turn out to be large as the extra dimension is small. We demonstrate that in the CPT-even case, the extra dimension manifests itself through a new scalar particle.
Cosmology With Extra Dimensions
Martín, J
2005-01-01
We review several properties of models that include extra dimensions, focusing on aspects related to cosmology and particle physics phenomenology. The properties of effective four dimensional inflationary geometry are studied in two distinct frameworks: (i) in Kaluza- Klein (KK) compactifications and (ii) in braneworld scenarios. From numerical simulations we find that inflationary braneworlds are unstable if the scale of inflation is too large in comparison with the stabilization scale of the interbrane distance. The analysis of perturbations confirms the existence of a tachyon associated with the volume modulus of the extra dimensions both in braneworlds and KK compactifications. With the numerical program BRANECODE non- perturbative properties of braneworlds are studied. We fully understand the non-perturbative consequences of this instability. Generic attractors are (i) an increase of the interbrane distance and the formation of a naked singularity, (ii) the brane colli...
Particle Creation in Kaluza-Klein Cosmology
Huang, W H
1989-01-01
We exactly calculate the particle number $N$ of scalar fields which are created from an initial vacuum in certain higher-dimensional cosmological models. The spacetimes in these models are the four-dimensional Chitre-Hartle or radiation-dominated universe with extra spaces which are static or power-law contracting. Except for some models in which no particles could be produced, the distribution of created particles shows a thermal behavior, at least in the limit of high three-dimensional "momentum" $k$. In some models, $N$ does not depend on the magnitude of the extra-dimensional "momentum" $k_c$ if $k_c$ is nonvanishing. A cutoff momentum $k_c$ may emerge in some models, and particles with $k\\le k_c$ could not be produced. We also discuss these results.
Search for universal extra dimensions in ppbar collisions
Energy Technology Data Exchange (ETDEWEB)
Abazov, Victor Mukhamedovich; /Dubna, JINR; Abbott, Braden Keim; /Oklahoma U.; Acharya, Bannanje Sripath; /Tata Inst.; Adams, Mark Raymond; /Illinois U., Chicago; Adams, Todd; /Florida State U.; Alexeev, Guennadi D.; /Dubna, JINR; Alkhazov, Georgiy D.; /St. Petersburg, INP; Alton, Andrew K.; /Michigan U. /Augustana Coll., Sioux Falls; Alverson, George O.; /Northeastern U.; Aoki, Masato; /Fermilab; Askew, Andrew Warren; /Florida State U. /Stockholm U.
2011-12-01
We present a search for Kaluza-Klein (KK) particles predicted by models with universal extra dimensions (UED) using a data set corresponding to an integrated luminosity of 7.3 fb{sup -1}, collected by the D0 detector at a p{bar p} center of mass energy of 1.96 TeV. The decay chain of KK particles can lead to a final state with two muons of the same charge. This signature is used to set a lower limit on the compactification scale of R{sup -1} > 260 GeV in a minimal UED model.
Dudas, E; Rubakov, V A
2006-01-01
We analyze the properties of a model with four-dimensional brane-localized Higgs type potential of a six dimensional scalar field satisfying the Dirichlet boundary condition on the boundary of a transverse two-dimensional compact space. The regularization of the localized couplings generates classical renormalization group running. A tachyonic mass parameter grows in the infrared, in analogy with the QCD gauge coupling in four dimensions. We find a phase transition at a critical value of the bare mass parameter such that the running mass parameter becomes large in the infrared precisely at the compactification scale. Below the critical coupling, the theory is in symmetric phase, whereas above it spontaneous symmetry breaking occurs. Close to the phase transition point there is a very light mode in the spectrum. The massive Kaluza-Klein spectrum at the critical coupling becomes independent of the UV cutoff.
Constraints on extra dimensions within the framework of the Standard Model Extension
Ali, Hamna; Overduin, James
2017-01-01
We consider Kaluza-Klein-type extensions of General Relativity in which extra dimensions may be large but do not necessarily have units of length. Additional coordinates of this kind necessarily violate Lorentz symmetry in principle, but whether or not the violations are detectable in practice depends on the dimension-transposing constants that convert them into lengths. We parametrize these violations in terms of coefficients associated with the matter sector of the Standard Model Extension, and show that the associated variation in fundamental quantities, such as rest mass or charge, must occur slowly, on cosmological scales.
Diphoton Resonance from a Warped Extra Dimension
Bauer, Martin; Neubert, Matthias
2016-01-01
We argue that extensions of the Standard Model (SM) with a warped extra dimension, which successfully address the hierarchy and flavor problems of elementary particle physics, can provide an elegant explanation of the 750 GeV diphoton excess recently reported by ATLAS and CMS. A gauge-singlet bulk scalar with O(1) couplings to fermions is identified as the new resonance S, and the vector-like Kaluza-Klein excitations of the SM quarks and leptons mediate its loop-induced couplings to photons and gluons. The electroweak gauge symmetry almost unambiguously dictates the bulk matter content and hence the hierarchies of the S->\\gamma\\gamma, WW, ZZ, Z\\gamma, t\\bar t and dijet decay rates. We find that the S->Z\\gamma decay mode is strongly suppressed, such that Br(S->Z\\gamma)Br(S->\\gamma\\gamma)S->\\gamma\\gamma signal requires Kaluza-Klein masses in the multi-TeV range, in perfect agreement with bounds from flavor physics and electroweak precision observables.
Diphoton resonance from a warped extra dimension
Bauer, Martin; Hörner, Clara; Neubert, Matthias
2016-07-01
We argue that extensions of the Standard Model (SM) with a warped extra dimension, which successfully address the hierarchy and flavor problems of elementary particle physics, can provide an elegant explanation of the 750 GeV diphoton excess recently reported by ATLAS and CMS. A gauge-singlet bulk scalar with {O} (1) couplings to fermions is identified as the new resonance S, and the vector-like Kaluza-Klein excitations of the SM quarks and leptons mediate its loop-induced couplings to photons and gluons. The electroweak gauge symmetry almost unambiguously dictates the bulk matter content and hence the hierarchies of the Sto γ γ, W W,ZZ,Zγ, toverline{t} and dijet decay rates. We find that the S → Zγ decay mode is strongly suppressed, such that Br( S → Zγ) /Br( S → γγ) converge and can be calculated in closed form with a remarkably simple result. Reproducing the observed pp → S → γγ signal requires Kaluza-Klein masses in the multi-TeV range, consistent with bounds from flavor physics and electroweak precision observables.
Graviton production with 2 jets at the LHC in large extra dimensions
Hagiwara, Kaoru; Li, Qiang; Mawatari, Kentarou; Zeppenfeld, Dieter
2008-01-01
We study Kaluza-Klein (KK) graviton production in the large extra dimensions model via 2 jets plus missing transverse momentum signatures at the LHC. We make predictions for both the signal and the dominant Zjj and Wjj backgrounds, where we introduce missing P_T-dependent jet selection cuts that ensure the smallness of the 2-jet rate over the 1-jet rate. With the same jet selection cuts, the distributions of the two jets and their correlation with the missing transverse momentum provide additional evidence for the production of an invisible massive object.
Search for Universal Extra Dimensions in p(p)over-bar Collisions
Energy Technology Data Exchange (ETDEWEB)
Abazov V. M.; Abbott B.; Acharya B. S.; Adams M.; Adams T.; Alexeev G. D.; Alkhazov G.; Alton A.; Alverson G.; Aoki M.; Askew A.; Asman B.; Atkins S.; Atramentov O.; Augsten K.; Avila C.; BackusMayes J.; Badaud F.; Bagby L.; Baldin B.; Bandurin D. V.; Banerjee S.; Barberis E.; Baringer P.; Barreto J.; Bartlett J. F.; Bassler U.; Bazterra V.; Bean A.; Begalli M.; Belanger-Champagne C.; Bellantoni L.; Beri S. B.; Bernardi G.; Bernhard R.; Bertram I.; Besancon M.; Beuselinck R.; Bezzubov V. A.; Bhat P. C.; Bhatia S.; Bhatnagar V.; Blazey G.; Blessing S.; Bloom K.; Boehnlein A.; Boline D.; Boos E. E.; Borissov G.; Bose T.; Brandt A.; Brandt O.; Brock R.; Brooijmans G.; Bross A.; Brown D.; Brown J.; Bu X. B.; Buehler M.; Buescher V.; Bunichev V.; Burdin S.; Burnett T. H.; Buszello C. P.; Calpas B.; Camacho-Perez E.; Carrasco-Lizarraga M. A.; Casey B. C. K.; Castilla-Valdez H.; Chakrabarti S.; Chakraborty D.; Chan K. M.; Chandra A.; Chapon E.; Chen G.; Chevalier-Thery S.; Cho D. K.; Cho S. W.; Choi S.; Choudhary B.; Cihangir S.; Claes D.; Clutter J.; Cooke M.; Cooper W. E.; Corcoran M.; Couderc F.; Cousinou M-C; Croc A.; Cutts D.; Das A.; Davies G.; de Jong S. J.; De La Cruz-Burelo E.; Deliot F.; Demina R.; Denisov D.; Denisov S. P.; Desai S.; Deterre C.; DeVaughan K.; Diehl H. T.; Diesburg M.; Ding P. F.; Dominguez A.; Dorland T.; Dubey A.; Dudko L. V.; Duggan D.; Duperrin A.; Dutt S.; Dyshkant A.; Eads M.; Edmunds D.; Ellison J.; Elvira V. D.; Enari Y.; Evans H.; Evdokimov A.; Evdokimov V. N.; Facini G.; Ferbel T.; Fiedler F.; Filthaut F.; Fisher W.; Fisk H. E.; Fortner M.; Fox H.; Fuess S.; Garcia-Bellido A.; Garcia-Guerra G. A.; Gavrilov V.; Gay P.; Geng W.; Gerbaudo D.; Gerber C. E.; Gershtein Y.; Ginther G.; Golovanov G.; Goryachev V. N.; Goussiou A.; Grannis P. D.; Greder S.; Greenlee H.; Greenwood Z. D.; Gregores E. M.; Grenier G.; Gris Ph; Grivaz J-F; Grohsjean A.; Gruenendahl S.; Gruenewald M. W.; Guillemin T.; Gutierrez G.; Gutierrez P.; Haas A.; Hagopian S.; Haley J.; Han L.; Harder K.; Harel A.; Hauptman J. M.; Hays J.; Head T.; Hebbeker T.; Hedin D.; Hegab H.; Heinson A. P.; Heintz U.; Hensel C.; Heredia-De La Cruz I.; Herner K.; Hesketh G.; Hildreth M. D.; Hirosky R.; Hoang T.; Hobbs J. D.; Hoeneisen B.; Hohlfeld M.; Hubacek Z.; Hynek V.; Iashvili I.; Ilchenko Y.; Illingworth R.; Ito A. S.; Jabeen S.; Jaffre M.; Jamin D.; Jayasinghe A.; Jesik R.; Johns K.; Johnson M.; Jonckheere A.; Jonsson P.; Joshi J.; Jung A. W.; Juste A.; Kaadze K.; Kajfasz E.; Karmanov D.; Kasper P. A.; Katsanos I.; Kehoe R.; Kermiche S.; Khalatyan N.; Khanov A.; Kharchilava A.; Kharzheev Y. N.; Kohli J. M.; Kozelov A. V.; Kraus J.; Kulikov S.; Kumar A.; Kupco A.; Kurca T.; Kuzmin V. A.; Lammers S.; Landsberg G.; Lebrun P.; Lee H. S.; Lee S. W.; Lee W. M.; Lellouch J.; Li H.; Li L.; Li Q. Z.; Lietti S. M.; Lim J. K.; Lincoln D.; Linnemann J.; Lipaev V. V.; Lipton R.; Liu Y.; Lobodenko A.; Lokajicek M.; de Sa R. Lopes; Lubatti H. J.; Luna-Garcia R.; Lyon A. L.; Maciel A. K. A.; Mackin D.; Madar R.; Magana-Villalba R.; Malik S.; Malyshev V. L.; Mansour J.; Maravin Y.; Martinez-Ortega J.; McCarthy R.; McGivern C. L.; Meijer M. M.; Melnitchouk A.; Menezes D.; Mercadante P. G.; Merkin M.; Meyer A.; Meyer J.; et al.
2012-03-30
We present a search for Kaluza-Klein (KK) particles predicted by models with universal extra dimensions (UED) using a data set corresponding to an integrated luminosity of 7.3 fb{sup -1}, collected by the D0 detector at a p{bar p} center-of-mass energy of 1.96 TeV. The decay chain of KK particles can lead to a final state with two muons of the same charge. This signature is used to set a lower limit on the compactification scale of R{sup -1} > 260 GeV in a minimal UED model.
Brane worlds theories with one or two extra dimensions
Salvio, Alberto
2013-01-01
This book is roughly divided in three parts. The first one is a general introduction to theories with extra dimensions and, more specifically, to brane worlds. Both old-fashioned topics (such as Kaluza-Klein theories) and more modern aspects (e.g. Large Extra Dimensions and Randall-Sundrum models) are discussed. The second and third parts (which we refer to as Part I and II respectively) are essentially two monographs. There, the reader is guided through the construction of the 4D effective field theory derived from higher dimensional (in particular five-dimensional and six-dimensional) models. Part I is devoted to the study of how the heavy Kaluza-Klein modes contribute to the low energy dynamics of the light modes. Part II concerns instead the analysis of the spectrum arising from non-standard compactifications of six-dimensional (supersymmetric) theories, involving a warp factor and conical defects in the internal manifold. Several applications of the above mentioned topics are discussed, providing an up t...
Degenerate Orbit Flip Homoclinic Bifurcations with Higher Dimensions
Institute of Scientific and Technical Information of China (English)
Ran Chao WU; Jian Hua SUN
2006-01-01
Bifurcations of a degenerate homoclinic orbit with orbit flip in high dimensional system are existence and uniqueness of 1-homoclinic orbit and 1-periodic orbit are given. Also considered is the existence of 2-homoclinic orbit and 2-periodic orbit. In additon, the corresponding bifurcation surfaces are given.
Search for large extra dimensions in the mono-photon final state at s**(1/2) = 1.96-TeV
Energy Technology Data Exchange (ETDEWEB)
Abazov, V.M.; /Dubna, JINR; Abbott, B.; /Oklahoma U.; Abolins, M.; /Michigan State U.; Acharya, B.S.; /Tata Inst.; Adams, M.; /Illinois U., Chicago; Adams, T.; /Florida State U.; Aguilo, E.; /Simon Fraser U.; Ahn, S.H.; /Korea U., KODEL; Ahsan, M.; /Kansas State U.; Alexeev, G.D.; /Dubna, JINR; Alkhazov, G.; /St. Petersburg, INP /Michigan U.
2008-03-01
The authors report on a search for large extra dimensions in a data sample of approximately 1 fb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV. They investigate Kaluza-Klein graviton production with a photon and missing transverse energy in the final state. At the 95% C.L. they set limits on the fundamental mass scale M{sub D} from 884 GeV to 778 GeV for 2 to 8 extra dimensions.
Energy Technology Data Exchange (ETDEWEB)
Carrera, Edgar Fernando [Florida State Univ., Tallahassee, FL (United States)
2008-12-01
This dissertation presents a search for large extra dimensions in the single photon plus missing transverse energy final states. We use a data sample of approximately 2.7 fb^{-1} of p$\\bar{p}$ collisions at √s = 1.96 TeV (recorded with the D^{-} detector) to investigate direct Kaluza Klein graviton production and set limits, at the 95% C.L., on the fundamental mass scale M_{D} from 970 GeV to 816 GeV for two to eight extra dimensions.
Compact Extra Dimensions in Quantum Mechanics
Deutschmann, Nicolas
2016-01-01
Extra-dimensions are a common topic in popular descriptions of theoretical physics with which undergraduate student most often have no contact in physics courses. This paper shows how students could be introduced to this topic by presenting an approach to two basic consequences of the presence of compact extra-dimensions based on undergraduate-level physics. The insensibility of low-energy physics to compact extra dimensions is illustrated in the context of non-relativistic quantum mechanics and the prediction of Kaluza-Klein excitations of particles is discussed in the framework of relativistic wave-equations. An exercise that could be used as a follow-up to the "particle in a box" is proposed.
Energy Technology Data Exchange (ETDEWEB)
Pankov, A. A., E-mail: pankov@ictp.it; Serenkova, I. A., E-mail: inna.serenkova@cern.ch; Tsytrinov, A. V., E-mail: tsytrin@gstu.by; Bednyakov, V. A., E-mail: Vadim.Bednyakov@cern.ch [Pavel Sukhoi Gomel State Technical University, ICTP (Abdus Salam International Centre for Theoretical Physics, Trieste, Italy) Affiliated Centre (Belarus)
2015-06-15
Prospects of discovering and identifying effects of extra spatial dimensions in dilepton and diphoton production at the Large Hadron Collider (LHC) are studied. Such effects may be revealed by the characteristic behavior of the invariant-mass distributions of dileptons and diphotons, and their identification can be performed on the basis of an analysis of their angular distributions. The discovery and identification reaches are estimated for the scale parameter M{sub S} of the Kaluza-Klein gravitational towers, which can be determined in experiments devoted to measuring the dilepton and diphoton channels at the LHC.
Indirect Collider Signals for Extra Dimensions
Hewett, J L
1999-01-01
A recent suggestion that quantum gravity may become strong near the weak scale has several testable consequences. In addition to probing for the new large (submillimeter) extra dimensions associated with these theories via gravitational experiments, one could search for the Kaluza Klein towers of massive gravitons which are predicted in these models and which can interact with the fields of the Standard Model. Here we examine the indirect effects of these massive gravitons being exchanged in fermion pair production in \\epem\\ annihilation and Drell-Yan production at hadron colliders. In the latter case, we examine a novel feature of this theory, which is the contribution of gluon gluon initiated processes to lepton pair production. We find that these processes provide strong bounds, up to several TeV, on the string scale which are essentially independent of the number of extra dimensions. In addition, we analyze the angular distributions for fermion pair production with spin-2 graviton exchanges and demonstrat...
Phenomenology of symmetry breaking from extra dimensions
Energy Technology Data Exchange (ETDEWEB)
Alfaro, Jorge [Facultad de Fisica, Pontificia Universidad Catolica de Chile, Casilla 306, Santiago 22 (Chile); Broncano, Alicia [Max Planck Institute for Physics, Foehringer Ring 6, 80805 Munich (Germany); Belen Gavela, Maria [Departamento de Fisica Teorica and Instituto de Fisica Teorica, Universidad Autonoma de Madrid, Cantoblanco, E-28049 Madrid (Spain); Rigolin, Stefano [Departamento de Fisica Teorica and Instituto de Fisica Teorica, Universidad Autonoma de Madrid, Cantoblanco, E-28049 Madrid (Spain); Salvatori, Matteo [Departamento de Fisica Teorica and Instituto de Fisica Teorica, Universidad Autonoma de Madrid, Cantoblanco, E-28049 Madrid (Spain)
2007-01-15
Motivated by the electroweak hierarchy problem, we consider theories with two extra dimensions in which the four-dimensional scalar fields are components of gauge boson in full space. We explore the Nielsen-Olesen instability for SU(N) on a torus, in the presence of a magnetic background. A field theory approach is developed, computing explicitly the minimum of the complete effective potential, including tri-linear and quartic couplings and determining the symmetries of the stable vacua. We also develop appropriate gauge-fixing terms when both Kaluza-Klein and Landau levels are present and interacting, discussing the interplay between the possible six and four dimensional choices. The equivalence between coordinate dependent and constant Scherk-Schwarz boundary conditions - associated to either continuous or discrete Wilson lines - is analyzed.
Constraints on Large Extra Dimensions from the MINOS Experiment
Energy Technology Data Exchange (ETDEWEB)
Adamson, P.; et al.
2016-12-16
We report new constraints on the size of large extra dimensions from data collected by the MINOS experiment between 2005 and 2012. Our analysis employs a model in which sterile neutrinos arise as Kaluza-Klein states in large extra dimensions and thus modify the neutrino oscillation probabilities due to mixing between active and sterile neutrino states. Using Fermilab’s Neutrinos at the Main Injector beam exposure of 10.56×10^{20} protons on target, we combine muon neutrino charged current and neutral current data sets from the Near and Far Detectors and observe no evidence for deviations from standard three-flavor neutrino oscillations. The ratios of reconstructed energy spectra in the two detectors constrain the size of large extra dimensions to be smaller than 0.45 μm at 90% C.L. in the limit of a vanishing lightest active neutrino mass. Stronger limits are obtained for nonvanishing masses.
Constraints on large extra dimensions from the MINOS experiment
Adamson, P.; Anghel, I.; Aurisano, A.; Barr, G.; Bishai, M.; Blake, A.; Bock, G. J.; Bogert, D.; Cao, S. V.; Carroll, T. J.; Castromonte, C. M.; Chen, R.; Childress, S.; Coelho, J. A. B.; Corwin, L.; Cronin-Hennessy, D.; de Jong, J. K.; de Rijck, S.; Devan, A. V.; Devenish, N. E.; Diwan, M. V.; Escobar, C. O.; Evans, J. J.; Falk, E.; Feldman, G. J.; Flanagan, W.; Frohne, M. V.; Gabrielyan, M.; Gallagher, H. R.; Germani, S.; Gomes, R. A.; Goodman, M. C.; Gouffon, P.; Graf, N.; Gran, R.; Grzelak, K.; Habig, A.; Hahn, S. R.; Hartnell, J.; Hatcher, R.; Holin, A.; Huang, J.; Hylen, J.; Irwin, G. M.; Isvan, Z.; James, C.; Jensen, D.; Kafka, T.; Kasahara, S. M. S.; Koizumi, G.; Kordosky, M.; Kreymer, A.; Lang, K.; Ling, J.; Litchfield, P. J.; Lucas, P.; Mann, W. A.; Marshak, M. L.; Mayer, N.; McGivern, C.; Medeiros, M. M.; Mehdiyev, R.; Meier, J. R.; Messier, M. D.; Miller, W. H.; Mishra, S. R.; Moed Sher, S.; Moore, C. D.; Mualem, L.; Musser, J.; Naples, D.; Nelson, J. K.; Newman, H. B.; Nichol, R. J.; Nowak, J. A.; O'Connor, J.; Orchanian, M.; Pahlka, R. B.; Paley, J.; Patterson, R. B.; Pawloski, G.; Perch, A.; Pfützner, M. M.; Phan, D. D.; Phan-Budd, S.; Plunkett, R. K.; Poonthottathil, N.; Qiu, X.; Radovic, A.; Rebel, B.; Rosenfeld, C.; Rubin, H. A.; Sail, P.; Sanchez, M. C.; Schneps, J.; Schreckenberger, A.; Schreiner, P.; Sharma, R.; Sousa, A.; Tagg, N.; Talaga, R. L.; Thomas, J.; Thomson, M. A.; Tian, X.; Timmons, A.; Todd, J.; Tognini, S. C.; Toner, R.; Torretta, D.; Tzanakos, G.; Urheim, J.; Vahle, P.; Viren, B.; Weber, A.; Webb, R. C.; White, C.; Whitehead, L.; Whitehead, L. H.; Wojcicki, S. G.; Zwaska, R.; Minos Collaboration
2016-12-01
We report new constraints on the size of large extra dimensions from data collected by the MINOS experiment between 2005 and 2012. Our analysis employs a model in which sterile neutrinos arise as Kaluza-Klein states in large extra dimensions and thus modify the neutrino oscillation probabilities due to mixing between active and sterile neutrino states. Using Fermilab's Neutrinos at the Main Injector beam exposure of 10.56 ×1 020 protons on target, we combine muon neutrino charged current and neutral current data sets from the Near and Far Detectors and observe no evidence for deviations from standard three-flavor neutrino oscillations. The ratios of reconstructed energy spectra in the two detectors constrain the size of large extra dimensions to be smaller than 0.45 μ m at 90% C.L. in the limit of a vanishing lightest active neutrino mass. Stronger limits are obtained for nonvanishing masses.
Constraints on Large Extra Dimensions from the MINOS Experiment
Adamson, P; Aurisano, A; Barr, G; Bishai, M; Blake, A; Bock, G J; Bogert, D; Cao, S V; Carroll, T J; Castromonte, C M; Chen, R; Childress, S; Coelho, J A B; Corwin, L; Cronin-Hennessy, D; de Jong, J K; de Rijck, S; Devan, A V; Devenish, N E; Diwan, M V; Escobar, C O; Evans, J J; Falk, E; Feldman, G J; Flanagan, W; Frohne, M V; Gabrielyan, M; Gallagher, H R; Germani, S; Gomes, R A; Goodman, M C; Gouffon, P; Graf, N; Gran, R; Grzelak, K; Habig, A; Hahn, S R; Hartnell, J; Hatcher, R; Holin, A; Huang, J; Hylen, J; Irwin, G M; Isvan, Z; James, C; Jensen, D; Kafka, T; Kasahara, S M S; Koizumi, G; Kordosky, M; Kreymer, A; Lang, K; Ling, J; Litchfield, P J; Lucas, P; Mann, W A; Marshak, M L; Mayer, N; McGivern, C; Medeiros, M M; Mehdiyev, R; Meier, J R; Messier, M D; Miller, W H; Mishra, S R; Sher, S Moed; Moore, C D; Mualem, L; Musser, J; Naples, D; Nelson, J K; Newman, H B; Nichol, R J; Nowak, J A; O'Connor, J; Orchanian, M; Pahlka, R B; Paley, J; Patterson, R B; Pawloski, G; Perch, A; Pfützner, M M; Phan, D D; Phan-Budd, S; Plunkett, R K; Poonthottathil, N; Qiu, X; Radovic, A; Rebel, B; Rosenfeld, C; Rubin, H A; Sail, P; Sanchez, M C; Schneps, J; Schreckenberger, A; Schreiner, P; Sharma, R; Sousa, A; Tagg, N; Talaga, R L; Thomas, J; Thomson, M A; Tian, X; Timmons, A; Todd, J; Tognini, S C; Toner, R; Torretta, D; Tzanakos, G; Urheim, J; Vahle, P; Viren, B; Weber, A; Webb, R C; White, C; Whitehead, L; Whitehead, L H; Wojcicki, S G; Zwaska, R
2016-01-01
We report new constraints on the size of large extra dimensions from data collected by the MINOS experiment between 2005 and 2012. Our analysis employs a model in which sterile neutrinos arise as Kaluza-Klein states in large extra dimensions and thus modify the neutrino oscillation probabilities due to mixing between active and sterile neutrino states. Using Fermilab's NuMI beam exposure of $10.56 \\times 10^{20}$ protons-on-target, we combine muon neutrino charged current and neutral current data sets from the Near and Far Detectors and observe no evidence for deviations from standard three-flavor neutrino oscillations. The ratios of reconstructed energy spectra in the two detectors constrain the size of large extra dimensions to be smaller than $0.45\\,\\mu\\text{m}$ at 90% C.L. in the limit of a vanishing lightest active neutrino mass. Stronger limits are obtained for non-vanishing masses.
Dimension of spacetime from the viewpoint of different fields
Kaviani, K
2014-01-01
In this paper a new geometric perspective on gravity is considered, proposing a different geometric feature of gravitational effects on Minkowski spacetime which can be seen as classification of the spacetime into some equivalence classes. By introducing some geometric objects based on noncommutative geometry, one can switch between field-picture and geometry-picture representing gravity and conclude dimensionally dependence of gravitational field equation and consequently emerging different features of gravity in spacetimes with different dimensions. Furthermore in the case of interaction of gravity with an external field, one can deduce that from the viewpoint of different fields, spacetime can be seen as an object with different dimensions. The proposal makes the possibility of resolving blackhole singularity and also observing some similarities with Kaluza-Klein-like theories where a reduction from higher to lower dimensional gravity is associated with emerging some different fields.
Deformed Spacetime Geometrizing Interactions in Four and Five Dimensions
Cardone, Fabio
2007-01-01
This volume provides a detailed discussion of the mathematical aspects and the physical applications of a new geometrical structure of space-time, based on a generalization ("deformation") of the usual Minkowski space, as supposed to be endowed with a metric whose coefficients depend on the energy. Such a formalism (Deformed Special Relativity, DSR) allows one to account for breakdown of local Lorentz invariance in the usual, special-relativistic meaning (however, Lorentz invariance is recovered in a generalized sense) to provide an effective geometrical description of the four fundamental interactions (electromagnetic, weak, strong and gravitational) Moreover, the four-dimensional energy-dependent space-time is just a manifestation of a larger, five-dimensional space in which energy plays the role of a fifth (non-compactified) dimension. This new five-dimensional scheme (Deformed Relativity in Five Dimensions, DR5) represents a true generalization of the usual Kaluza-Klein (KK) formalism. The mathematical pr...
Large extra dimensions, sterile neutrinos and solar neutrino data.
Caldwell, D O; Mohapatra, R N; Yellin, S J
2001-07-23
Solar, atmospheric, and LSND neutrino oscillation results require a light sterile neutrino, nu(B), which can exist in the bulk of extra dimensions. Solar nu(e), confined to the brane, can oscillate in the vacuum to the zero mode of nu(B) and via successive Mikheyev-Smirnov-Wolfenstein transitions to Kaluza-Klein states of nu(B). This new way to fit solar data is provided by both low and intermediate string scale models. From average rates seen in the three types of solar experiments, the Super-Kamiokande spectrum is predicted with 73% probability, but dips characteristic of the 0.06 mm extra dimension should be seen in the SNO spectrum.
A smoothed string-like braneworld in six dimensions
Energy Technology Data Exchange (ETDEWEB)
Araujo, J.C.B.; Silva, J.E.G.; Veras, D.F.S.; Almeida, C.A.S. [Universidade Federal do Ceara, Departamento de Fisica, C.P. 6030, Fortaleza, Ceara (Brazil)
2015-03-01
We propose a static and axisymmetric braneworld in six dimensions as a string-like model extension. For a subtle warp function, this scenario provides near brane corrections. By varying the bulk cosmological constant, we obtain a source which passes through different phases. The solution is defined both for the interior and for the exterior of the string and satisfies all the energy conditions. A smoothed gravitational massless mode is localized on the brane, of which the core is displaced from the origin. In contrast to the thin-string model, the massive solutions have a high amplitude near the brane. Furthermore, by means of an analog quantum potential analysis, we show that only s-wave gravitational Kaluza-Klein modes are permissible. (orig.)
New Regulators for Quantum Field Theories with Compactified Extra Dimensions. I: Fundamentals
Bauman, Sky
2007-01-01
In this paper, we propose two new regulators for quantum field theories in spacetimes with compactified extra dimensions. We refer to these regulators as the ``extended hard cutoff'' (EHC) and ``extended dimensional regularization'' (EDR). Although based on traditional four-dimensional regulators, the key new feature of these higher-dimensional regulators is that they are specifically designed to handle mixed spacetimes in which some dimensions are infinitely large and others are compactified. Moreover, unlike most other regulators which have been used in the extra-dimension literature, these regulators are designed to respect the original higher-dimensional Lorentz and gauge symmetries that exist prior to compactification, and not merely the four-dimensional symmetries which remain afterward. This distinction is particularly relevant for calculations of the physics of the excited Kaluza-Klein modes themselves, and not merely their radiative effects on zero modes. By respecting the full higher-dimensional sym...
Characteristic Classes for the Degenerations of Two-Plane Fields in Four Dimensions
Kazarian, M E; Shapiro, B; Kazarian, Maxim; Montgomery, Richard; Shapiro, Boris
1997-01-01
There is a remarkable type of field of two-planes special to four dimensions known as an Engel distributions. They are the only stable regular distributions besides the contact, quasi-contact and line fields. If an arbitrary two-plane field on a four-manifold is slightly perturbed then it will be Engel at generic points. On the other hand, if a manifold admits an oriented Engel structure then the manifold must be parallelizable and consequently the alleged Engel distribution must have a degeneration loci -- a point set where the Engel conditions fails. By a theorem of Zhitomirskii this locus is a finite union of surfaces. We prove that these surfaces represent Chern classes associated to the distribution.
The Kaluza-Klein monopole in a massive IIA background
Eyras, E; Lozano, Y
1999-01-01
We construct the effective action of the KK monopole in a massive Spe IIA background. We follow two approaches. First we construct a massive M-theory KK monopole from which the IIA monopole is obtained by double dimensional reduction. This eleven-dimensional monopole contains two isometries: one und
Kaluza-Klein Gluons as a Diagnostic of Warped Models
Lillie, Benjamin Huntington; Tait, Tim M P
2007-01-01
We study the properties of $g^{1}$, the first excited state of the gluon in representative variants of the Randall Sundrum model with the Standard Model fields in the bulk. We find that measurements of the coupling to light quarks (from the inclusive cross-section for $pp\\to g^{1} \\to t\\bar t$), the coupling to bottom quarks (from the rate of $pp\\to g^{1} b$), as well as the overall width, can provide powerful discriminants between the models. In models with large brane kinetic terms, the $g^1$ resonance can even potentially be discovered decaying into dijets against the large QCD background. We also derive bounds based on existing Tevatron searches for resonant $t \\bar{t}$ production and find that they require $M_{g^{1}} \\gtrsim 950$ GeV. In addition we explore the pattern of interference between the $g^1$ signal and the non-resonant SM background, defining an asymmetry parameter for the invariant mass distribution. The interference probes the relative signs of the couplings of the $g^{1}$ to light quark pai...
Constraints on the size of the extra dimension from KK gravitinos decay
Energy Technology Data Exchange (ETDEWEB)
Gherson, David [Institut de Physique Nucleaire de Lyon (IPNL), Universite Claude Bernard Lyon-I, Villeurbanne (France)
2007-07-01
We study the consequences of the gravitino decay into dark matter. We suppose that the lightest neutralino is the main component of dark matter. In our framework gravitino is heavy enough to decay before Big Bang Nucleosynthesis starts. We consider a model coming from a five dimensional supergravity compactified on S{sup 1}/Z{sub 2} with gravity in the bulk and matter localized on tension-less branes at the orbifold fixed points. We require that the dark matter, which is produced thermally and in the decay of Kaluza-Klein modes of gravitino, has an abundance compatible with observation. We deduce from our model that there are curves of constraints between the size of the extra-dimension and the reheating temperature of the universe after inflation. (author)
Effects of non-minimal Universal Extra Dimension on $B\\rightarrow X_s\\gamma$
Datta, Anindya
2016-01-01
We estimate contributions from Kaluza-Klein excitations of third generation quarks and gauge bosons to the branching ratio of $B\\rightarrow X_s\\gamma$ decay process in 5-Dimensional Universal Extra Dimensional scenario with non-vanishing boundary localised terms. This model is conventionally known as non-minimal Universal Extra Dimensional model. We have derived the lower limit on the size of the extra dimension by comparing our theoretical estimation of the branching ratio which includes next-to-next-to leading order QCD corrections with its experimentally measured value. Coefficients of the boundary localised terms have also been constrained. 95 \\% C.L. lower limit on inverse of radius of compactification ($R^{-1}$) can be as large as 670 GeV for some choice of the value of coefficients of boundary localised terms.
A pure Dirac's analysis for a four dimensional BF-like theory with a compact dimension
Escalante, Alberto
2013-01-01
In the context of extra dimensions, we perform a detailed Dirac's canonical analysis for a topological four dimensional BF-like theory. By performing the compactification process a la Kaluza-Klein, we find out the relevant symmetries of the theory, namely, the full structure of the constraints and the extended action. We show that the extended Hamiltonian is a linear combination of first class constraints, which means that the general covariance of the theory is not affected by the compactification process. Furthermore, in order to carry out the correct counting of physical degrees of freedom, we show that must be taken into account the reducibility conditions among the first class constraints associated to the excited KK modes. Finally, we perform the Hamiltonian analysis of Maxwell theory written as a $BF$-like theory, we analyze the constraints of the theory and the results obtained are compared with those found in the literature.
Hooper, D; Hooper, Dan; Zaharijas, Gabrijela
2007-01-01
There are compelling reasons to think that new physics will appear at or below the TeV-scale. It is not known what form this new physics will take, however. Although The Large Hadron collider is very likely to discover new particles associated with the TeV-scale, it may be difficult for it to determine the nature of those particles, whether superpartners, Kaluza-Klein modes or other states. In this article, we consider how direct and indirect dark matter detection experiments may provide information complementary to hadron colliders, which can be used to discriminate between supersymmetry, models with universal extra dimensions, and Little Higgs theories. We find that, in many scenarios, dark matter experiments can be effectively used to distinguish between these possibilities.
Charged Heterotic Black-Holes in Four and Two Dimensions
Cardoso, Gabriel Lopes
1998-01-01
We consider four-dimensional charged black-holes occuring in toroidally compactified heterotic string theory, whose ten-dimensional interpretation involves a Kaluza-Klein monopole and a five-brane. We show that these four-dimensional black-holes can be connected to two-dimensional charged heterotic black-holes upon removal of the constants appearing in the harmonic functions associated with the Kaluza-Klein monopole and the five-brane.
Simple SO(10) GUT in five dimensions
Fukuyama, Takeshi; Okada, Nobuchika
2008-07-01
A simple supersymmetric SO(10) grand unified theory (GUT) in five dimensions is considered. The fifth dimension is compactified on the S1/(Z2×Z2') orbifold possessing two inequivalent fixed points. In our setup, all matter and Higgs multiplets reside on one brane (PS brane) where the original SO(10) gauge group is broken down to the Pati-Salam (PS) gauge group, SU(4)c×SU(2)L×SU(2)R, by the orbifold boundary condition, while only the SO(10) gauge multiplet resides in the bulk. The further breaking of the PS symmetry to the standard model gauge group is realized by Higgs multiplets on the PS brane as usual in four-dimensional models. Proton decay is fully suppressed. In our simple setup, the gauge coupling unification is realized after incorporating threshold corrections of Kaluza-Klein modes. When supersymmetry is assumed to be broken on the other brane, supersymmetry breaking is transmitted to the PS brane through the gaugino mediation with the bulk gauge multiplet.
LHC Signals from Warped Extra Dimensions
Energy Technology Data Exchange (ETDEWEB)
Agashe, K.; Belyaev, A.; Krupovnickas, T.; Perez, G.; Virzi, J.
2006-12-06
We study production of Kaluza-Klein gluons (KKG) at the Large Hadron Collider (LHC) in the framework of a warped extra dimension with the Standard Model (SM) fields propagating in the bulk. We show that the detection of KK gluon is challenging since its production is suppressed by small couplings to the proton's constituents. Moreover, the KK gluon decaysmostly to top pairs due to an enhanced coupling and hence is broad. Nevertheless, we demonstrate that for MKKG<~;; 4 TeV, 100 fb-1 of data at the LHC can provide discovery of the KK gluon. We utilize a sizeable left-right polarization asymmetry from the KK gluon resonance to maximize the signal significance, and we explore the novel feature of extremely highly energetic"top-jets." We briefly discuss how the detection of electroweak gauge KK states (Z/W) faces a similar challenge since their leptonic decays ("golden" modes) are suppressed. Our analysis suggests that other frameworks, for example little Higgs, which rely on UV completion via strong dynamics might face similar challenges, namely (1) Suppressed production rates for the new particles (such as Z'), due to their"lightfermion-phobic" nature, and (2) Difficulties in detection since the new particles are broad and decay predominantly to third generation quarks and longitudinal gauge bosons.
Exploring the Universal Extra Dimension at the LHC
Bhattacharyya, Gautam; Majee, Swarup Kumar; Raychaudhuri, Amitava
2009-01-01
Besides supersymmetry, the other prime candidate of physics beyond the standard model (SM), crying out for verification at the CERN Large Hadron Collider (LHC), is extra-dimension. To hunt for effects of Kaluza-Klein (KK) excitations of known fermions and bosons is very much in the agenda of the LHC. These KK states arise when the SM particles penetrate in the extra space-like dimension(s). In this paper, we consider a 5d scenario, called `Universal Extra Dimension', where the extra space coordinate, compactified on an orbifold $S^1/Z_2$, is accessed by {\\em all} the particles. The KK number ($n$) is conserved at all tree level vertices. This entails the production of KK states in pairs and renders the lightest KK particle stable, which leaves the detector carrying away missing energy. The splitting between different KK flavors is controlled by the zero mode masses and the bulk- and brane-induced one-loop radiative corrections. We concentrate on the production of an $n=1$ KK electroweak gauge boson in associa...
Unified Gauge Theories and Reduction of Couplings: from Finiteness to Fuzzy Extra Dimensions
Directory of Open Access Journals (Sweden)
George Zoupanos
2008-02-01
Full Text Available Finite Unified Theories (FUTs are N = 1 supersymmetric Grand Unified Theories, which can be made all-loop finite, both in the dimensionless (gauge and Yukawa couplings and dimensionful (soft supersymmetry breaking terms sectors. This remarkable property, based on the reduction of couplings at the quantum level, provides a drastic reduction in the number of free parameters, which in turn leads to an accurate prediction of the top quark mass in the dimensionless sector, and predictions for the Higgs boson mass and the supersymmetric spectrum in the dimensionful sector. Here we examine the predictions of two such FUTs. Next we consider gauge theories defined in higher dimensions, where the extra dimensions form a fuzzy space (a finite matrix manifold. We reinterpret these gauge theories as four-dimensional theories with Kaluza-Klein modes. We then perform a generalized à la Forgacs-Manton dimensional reduction. We emphasize some striking features emerging such as (i the appearance of non-Abelian gauge theories in four dimensions starting from an Abelian gauge theory in higher dimensions, (ii the fact that the spontaneous symmetry breaking of the theory takes place entirely in the extra dimensions and (iii the renormalizability of the theory both in higher as well as in four dimensions. Then reversing the above approach we present a renormalizable four dimensional SU(N gauge theory with a suitable multiplet of scalar fields, which via spontaneous symmetry breaking dynamically develops extra dimensions in the form of a fuzzy sphere SN2. We explicitly find the tower of massive Kaluza-Klein modes consistent with an interpretation as gauge theory on M4 × S2, the scalars being interpreted as gauge fields on S2. Depending on the parameters of the model the low-energy gauge group can be SU(n, or broken further to SU(n1 × SU(n2 × U(1. Therefore the second picture justifies the first one in a renormalizable framework but in addition has the potential to
Coradeschi, Francesco; Dominici, Daniele
2010-01-01
We consider the continuum limit of a moose model corresponding to a generalization to N sites of the Degenerate BESS model. The five dimensional formulation emerging in this limit is a realization of a RS1 type model with SU(2)_L x SU(2)_R in the bulk, broken by boundary conditions and a vacuum expectation value on the infrared brane. A low energy effective Lagrangian is derived by means of the holographic technique and corresponding bounds on the model parameters are obtained.
Supergravity and Supersymmetry Breaking in Four and Five Dimensions
Ellis, Jonathan Richard; Pokorski, Stefan; Thomas, S; Ellis, John; Lalak, Zygmunt; Pokorski, Stefan; Thomas, Steven
1999-01-01
We discuss supersymmetry breaking in the field-theoretical limit of the strongly-coupled heterotic string compactified on a Calabi-Yau manifold, from the different perspectives of four and five dimensions. The former applies to light degrees of freedom below the threshold for five-dimensional Kaluza-Klein excitations, whereas the five-dimensional perspective is also valid up to the Calabi-Yau scale. We show how, in the latter case, two gauge sectors separated in the fifth dimension are combined to form a consistent four-dimensional supergravity. In the lowest order of the $\\kappa^{2/3}$ expansion, we show how a four-dimensional supergravity with gauge kinetic function $f_{1,2}=S$ is reproduced, and we show how higher-order terms give rise to four-dimensional operators that differ in the two gauge sectors. In the four-dimensional approach, supersymmetry is seen to be broken when condensates form on one or both walls, and the goldstino may have a non-zero dilatino component. As in the five-dimensional approach,...
Supergravity and supersymmetry breaking in four and five dimensions
Ellis, Jonathan Richard; Pokorski, Stefan; Thomas, S
1999-01-01
We discuss supersymmetry breaking in the field-theoretical limit of the strongly coupled heterotic string compactified on a Calabi-Yau manifold, from the different perspectives of four and five dimensions. The former applies to light degrees of freedom below the threshold for five-dimensional Kaluza-Klein excitations, whereas the five-dimensional perspective is also valid up to the Calabi-Yau scale. We show how, in the latter case, two gauge sectors separated in the fifth dimension are combined to form a consistent four- dimensional supergravity. In the lowest order of the kappa /sup 2/3/ expansion, we show how a four-dimensional supergravity with gauge kinetic function f/sub 1,2/=S is reproduced, and we show how higher- order terms give rise to four-dimensional operators that differ in the two gauge sectors. In the four-dimensional approach, supersymmetry is seen to be broken when condensates form on one or both walls, and the goldstino may have a non-zero dilatino component. As in the five-dimensional appro...
Auto-Concealment of Supersymmetry in Extra Dimensions
Dimopoulos, Savas; March-Russell, John; Scoville, James
2014-01-01
In supersymmetric (SUSY) theories with extra dimensions the visible energy in sparticle decays can be significantly reduced and its energy distribution broadened, thus significantly weakening the present collider limits on SUSY. The mechanism applies when the lightest supersymmetric particle (LSP) is a bulk state-- e.g. a bulk modulino, axino, or gravitino-- the size of the extra dimensions larger than ~$10^{-14}$ cm, and for a broad variety of visible sparticle spectra. In such cases the lightest ordinary supersymmetric particle (LOSP), necessarily a brane-localised state, decays to the Kaluza-Klein (KK) discretuum of the LSP. This dynamically realises the compression mechanism for hiding SUSY as decays into the more numerous heavier KK LSP states are favored. We find LHC limits on right-handed slepton LOSPs evaporate, while LHC limits on stop LOSPs weaken to ~350-410 GeV compared to ~700 GeV for a stop decaying to a massless LSP. Similarly, for the searches we consider, present limits on direct production o...
Classical models of affinely-rigid bodies with "thickness" in degenerate dimension
Kovalchuk, Vasyl
2009-01-01
The special interest is devoted to such situations when the material space of our object with affine degrees of freedom has generally lower dimension than the one of the physical space. In other words when we have the $m$-dimensional affinely-rigid body moving in the $n$-dimensional physical space, $m
Higher-spin Chern-Simons theories in odd dimensions
Energy Technology Data Exchange (ETDEWEB)
Engquist, Johan [Institute for Theoretical Physics and Spinoza Institute, Utrecht University, 3508 TD Utrecht (Netherlands)], E-mail: j.engquist@phys.uu.nl; Hohm, Olaf [Institute for Theoretical Physics and Spinoza Institute, Utrecht University, 3508 TD Utrecht (Netherlands)], E-mail: o.hohm@phys.uu.nl
2007-12-10
We construct consistent bosonic higher-spin gauge theories in odd dimensions D>3 based on Chern-Simons forms. The gauge groups are infinite-dimensional higher-spin extensions of the anti-de Sitter groups SO(D-1,2). We propose an invariant tensor on these algebras, which is required for the definition of the Chern-Simons action. The latter contains the purely gravitational Chern-Simons theories constructed by Chamseddine, and so the entire theory describes a consistent coupling of higher-spin fields to a particular form of Lovelock gravity. It contains topological as well as non-topological phases. Focusing on D=5 we consider as an example for the latter an AdS{sub 4}xS{sup 1} Kaluza-Klein background. By solving the higher-spin torsion constraints in the case of a spin-3 field, we verify explicitly that the equations of motion reduce in the linearization to the compensator form of the Fronsdal equations on AdS{sub 4}.
Gamma ray lines from a universal extra dimension
Energy Technology Data Exchange (ETDEWEB)
Bertone, Gianfranco; Jackson, C. B.; Shaughnessy, Gabe; Tait, Tim M.P.; Vallinotto, Alberto
2012-03-01
Indirect Dark Matter searches are based on the observation of secondary particles produced by the annihilation or decay of Dark Matter. Among them, gamma-rays are perhaps the most promising messengers, as they do not suffer deflection or absorption on Galactic scales, so their observation would directly reveal the position and the energy spectrum of the emitting source. Here, we study the detailed gamma-ray energy spectrum of Kaluza--Klein Dark Matter in a theory with 5 Universal Extra Dimensions. We focus in particular on the two body annihilation of Dark Matter particles into a photon and another particle, which produces monochromatic photons, resulting in a line in the energy spectrum of gamma rays. Previous calculations in the context of the five dimensional UED model have computed the line signal from annihilations into \\gamma \\gamma, but we extend these results to include \\gamma Z and \\gamma H final states. We find that these spectral lines are subdominant compared to the predicted \\gamma \\gamma signal, but they would be important as follow-up signals in the event of the observation of the \\gamma \\gamma line, in order to distinguish the 5d UED model from other theoretical scenarios.
Large, Extra Dimensions at the Deep Underground Neutrino Experiment
Berryman, Jeffrey M; Kelly, Kevin J; Peres, O L G; Tabrizi, Zahra
2016-01-01
We investigate the potential of the long-baseline Deep Underground Neutrino Experiment (DUNE) to study large-extra-dimension (LED) models originally proposed to explain the smallness of neutrino masses by postulating that right-handed neutrinos, unlike all standard model fermion fields, can propagate in the bulk. The massive Kaluza-Klein (KK) modes of the right-handed neutrino fields modify the neutrino oscillation probabilities and can hence affect their propagation. We show that, as far as DUNE is concerned, the LED model is indistinguishable from a $(3 + 3N)$-neutrino framework for modest values of $N$; $N$ = 1 is usually a very good approximation. Nonetheless, there are no new sources of $CP$-invariance violation other than one $CP$-odd phase that can be easily mapped onto the $CP$-odd phase in the standard three-neutrino paradigm. We analyze the sensitivity of DUNE to the LED framework, and explore the capability of DUNE to differentiate the LED model from the three-neutrino scenario and from a generic $...
Large extra dimensions at the Deep Underground Neutrino Experiment
Berryman, Jeffrey M.; de Gouvêa, André; Kelly, Kevin J.; Peres, O. L. G.; Tabrizi, Zahra
2016-08-01
We investigate the potential of the long-baseline Deep Underground Neutrino Experiment (DUNE) to study large-extra-dimension (LED) models originally proposed to explain the smallness of neutrino masses by postulating that right-handed neutrinos, unlike all standard model fermion fields, can propagate in the bulk. The massive Kaluza-Klein (KK) modes of the right-handed neutrino fields modify the neutrino oscillation probabilities and can hence affect their propagation. We show that, as far as DUNE is concerned, the LED model is indistinguishable from a (3 +3 N )-neutrino framework for modest values of N ; N =1 is usually a very good approximation. Nonetheless, there are no new sources of C P -invariance violation other than one C P -odd phase that can be easily mapped onto the C P -odd phase in the standard three-neutrino paradigm. We analyze the sensitivity of DUNE to the LED framework and explore the capability of DUNE to differentiate the LED model from the three-neutrino scenario and from a generic (3 +1 )-neutrino model.
B-factory Signals for a Warped Extra Dimension
Agashe, K; Soni, A; Agashe, Kaustubh; Perez, Gilad; Soni, Amarjit
2004-01-01
We study predictions for B-physics in a class of models, recently introduced, with a non-supersymmetric warped extra dimension. In these models few ($\\sim 3$) TeV Kaluza-Klein masses are consistent with electroweak data due to bulk custodial symmetry. Furthermore, there is an analog of GIM mechanism which is violated by the heavy top quark (just as in SM) leading to striking signals at $B$-factories: (i) New Physics (NP) contributions to $\\Delta F= 2$ transitions are comparable to SM. This implies that, within this NP model, the success of the SM unitarity triangle fit is a ``coincidence''. Thus, clean extractions of unitarity angles via e.g. $B \\to \\pi \\pi,\\rho \\pi, \\rho \\rho, DK$ are likely to be affected, in addition to O(1) deviation from SM prediction in $B_s$ mixing. (ii) O(1) deviation from SM predictions for $B \\to X_s l^+ l^-$ in rate as well as in forward-backward and direct CP asymmetry. (iii) Large mixing-induced CP asymmetry in radiative B decays, wherein the SM unamibgously predicts very small a...
Extra dimensions, SN1987a, and nucleon-nucleon scattering data
Hanhart, C; Reddy, S; Savage, M J; Hanhart, Christoph; Phillips, Daniel R.; Reddy, Sanjay; Savage, Martin J.
2001-01-01
One of the strongest constraints on the existence of large, compact, "gravity-only" dimensions comes from SN1987a. If the rate of energy loss into these putative extra dimensions is too high, then the neutrino pulse from the supernova will differ from that actually seen. The dominant mechanism for the production of Kaluza-Klein gravitons and dilatons in the supernova is via gravistrahlung and dilastrahlung from the nucleon-nucleon system. In this paper we compute the rates for these processes in a model-independent way using low-energy theorems which relate the emissivities to the measured nucleon-nucleon cross section. This is possible because for soft gravitons and dilatons the leading contribution to the energy-loss rate is from graphs in which the gravitational radiation is produced from external nucleon legs. Previous calculations neglected these mechanisms. We re-evaluate the bounds on toroidally-compactified "gravity-only" dimensions (GODs), and find that consistency with the observed SN1987a neutrino ...
One-loop effects of extra dimensions on the WWγ and WWZ vertices
Flores-Tlalpa, A.; Montaño, J.; Novales-Sánchez, H.; Ramírez-Zavaleta, F.; Toscano, J. J.
2011-01-01
The one-loop contribution of the excited Kaluza-Klein (KK) modes of the SUL(2) gauge group on the off-shell W-W+γ and W-W+Z vertices is calculated in the context of a pure Yang-Mills theory in five dimensions and its phenomenological implications discussed. The use of a gauge-fixing procedure for the excited KK modes that is covariant under the standard gauge transformations of the SUL(2) group is stressed. A gauge-fixing term and the Faddeev-Popov ghost sector for the KK gauge modes that are separately invariant under the standard gauge transformations of SUL(2) are presented. It is shown that the one-loop contributions of the KK modes to the off-shell W-W+γ and W-W+Z vertices are free of ultraviolet divergences and well-behaved at high energies. It is found that for a size of the fifth dimension of R-1˜1TeV, the one-loop contribution of the KK modes to these vertices is about 1 order of magnitude lower than the corresponding standard model radiative correction. This contribution is similar to the one estimated for new gauge bosons contributions in other contexts. Tree-level effects on these vertices induced by operators of higher canonical dimension are also investigated. It is found that these effects are lower than those generated at the one-loop order by the KK gauge modes.
Qiang, Li-E.; Zhao, Shu Hong; Xu, Peng
2016-12-01
Gravitational waves from coalescing black-hole binaries (BHBs) were recently observed by the advanced LIGO detectors. Based on the perturbation analysis, for general Kaluza-Klein theories with compact extra dimensions, we find a 1st-order post-Newtonian correction to the inspiral gravitational waveforms of black-hole binaries, that comes from the variations of the volume of the extra dimensions in near source zones. Such correction depends on a new parameter χ=\\frac{n}{2+n} with n the dimensionality of the extra space and it is irrelevant to the particular choice of the topology of the extra space. For the ideal case of a black-hole binary system following nearly circular orbital motion with almost equal or intermediate mass ratio, such higher-dimensional corrections to the chirping amplitude are worked out. Giving the power of tracing inspiral waves from coalescing massive BHBs with high signal-to-noise ratios, the planned space-borne antennas such as the eLISA and DECIGO may give us a measurement of the parameter χ in the near future and may serve us as new probes in the searching for the evidence of the hidden compact dimensions.
Hanhart, C; Phillips, D R; Reddy, S; Hanhart, Christoph; Pons, Jose A.; Phillips, Daniel R.; Reddy, Sanjay
2001-01-01
The existence of compact dimensions which are accessible only to gravity represents an intriguing possible solution to the hierarchy problem. At present the strongest constraint on the existence of such compact Gravity-Only Dimensions (GODs) comes from SN1987a. Here we report on the first self-consistent simulations of the early, neutrino-emitting phase of a proto-neutron star which include energy losses due to the coupling of the Kaluza-Klein modes of the graviton which arise in a world with GODs. We compare the neutrino signals from these simulations to that from SN1987a and use a rigorous probabilistic analysis to derive improved bounds for the radii of such GODs. We find that the possibility that there are two compact extra dimensions with radii larger than 0.66 $\\mu$m is excluded at the 95% confidence level---as is the possibility that there are three compact extra dimensions larger than 0.8 nm.
One-loop effects of extra dimensions on the WW\\gamma and WWZ vertices
Flores-Tlalpa, A; Novales-Sánchez, H; Ramirez-Zavaleta, F; Toscano, J J
2010-01-01
The one-loop contribution of the excited Kaluza-Klein (KK) modes of the $SU_L(2)$ gauge group on the off-shell $WW\\gamma$ and $WWZ$ vertices is calculated in the context of a pure Yang-Mills theory in five dimensions and its phenomenological implications discussed. The use of a gauge-fixing procedure for the excited KK modes that is covariant under the standard gauge transformations of the $SU_L(2)$ group is stressed. A gauge-fixing term and the Faddeev-pov ghost sector for the KK gauge modes that are separately invariant under the standard gauge transformations of $SU_L(2)$ are presented. It is shown that the contributions of the KK modes to the off shell $WW\\gamma$ and $WWZ$ vertices are free of ultraviolet divergences and well-behaved at high energies. It is found that for a size of the fifth dimension of the order of 1 TeV, the one-loop contribution of the KK modes to these vertices is about one order of magnitude lower than the corresponding standard model radiative correction. This contribution is simil...
Bubbles of Nothing in Flux Compactifications
Blanco-Pillado, Jose J
2010-01-01
We construct a simple $5d$ flux compactification stabilized by a complex scalar field winding the extra dimension and demonstrate an instability via nucleation of a bubble of nothing. This occurs when the Kaluza -- Klein dimension degenerates to a point, defining the bubble surface. Because the extra dimension is stabilized by a flux, the bubble surface must be charged, in this case under the axionic part of the complex scalar. This smooth geometry can be seen as a de Sitter topological defect with asymptotic behavior identical to the pure compactification. We discuss how a similar construction can be implemented in more general Freund -- Rubin compactifications.
Effect of compactification of twisted toroidal extra-dimension on sterile neutrino
Mohanty, Ajit Kumar
2016-01-01
We consider a toroidal extra-dimensional space with shape moduli $\\theta$ which is the angle between the two large extra dimensions $R_1$ and $R_2$ (twisted LED with $\\delta=2$). The Kaluza-Klein (KK) compactification results in a tower of KK bulk neutrinos which are sterile in nature and couple to the active neutrinos in the brane. The active-sterile mixing probability strongly depends on the angle $\\theta$ due to changing pattern of KK mass gaps which leads to level crossing. Considering only the first two lowest KK states in analogy with $(3+2)$ model, it is shown that $|U_{\\alpha 4}| > |U_{\\alpha 5}|$ when $\\theta = \\pi/2$ corresponding to the case of a normal torus. Since $\\Delta_{14}^2 < \\Delta_{15}^2$, this is expected in normal LED model as higher the sterile mass lower is the mixing probability. Contrary to this expectation, it is found that there exists a range in $\\theta$ where $|U_{\\alpha 5}| \\ge |U_{\\alpha 4}|$ even though $\\Delta m_{14}^2 < \\Delta m_{15}^2$ which has been demonstrated qant...
Search for Large Extra Dimensions Based on Observations of Neutron Stars with the Fermi-LAT
Energy Technology Data Exchange (ETDEWEB)
Berenji, Bijan [Stanford Univ., CA (United States)
2012-09-19
Large extra dimensions (LED) have been proposed to account for the apparent weakness of gravitation. These theories also indicate that the postulated massive Kaluza-Klein (KK) gravitons may be produced by nucleon-nucleon bremsstrahlung in the course of core collapse of supernovae. Hannestad and Raffelt have predicted energy spectra of gamma ray emission from the decay of KK gravitons trapped by the gravity of the remnant neutron stars (NS). These and other authors have used EGRET data on NS to obtain stringent limits on LED. Fermi-LAT is observing radio pulsar positions obtained from radio and x-ray catalogs. NS with certain characteristics are unlikely emitter of gamma rays, and emit in radio and perhaps x-rays. This talk will focus on the blind analysis we plan to perform, which has been developed using the 1st 2 months of all sky data and Monte Carlo simulations, to obtain limits on LED based on about 1 year of Fermi-LAT data. Preliminary limits from this analysis using these first 2 months of data will be also be discussed.
Darabi, F
2009-01-01
We study a $(4+D)$-dimensional Kaluza-Klein cosmology with a Robertson-Walker type metric having two scale factors $a$ and $R$, corresponding to $D$-dimensional internal space and 4-dimensional universe, respectively. By introducing an exotic matter in the form of perfect fluid with an special equation of state, as the space-time part of the higher dimensional energy-momentum tensor, a four dimensional effective decaying cosmological term appears as $\\lambda \\sim R^{-m}$ with $0 \\leq m\\leq 2$, playing the role of an evolving dark energy in the universe. By taking $m=2$, which has some interesting implications in reconciling observations with inflationary models and is consistent with quantum tunneling, the resulting Einstein's field equations yield the exponential solutions for the scale factors $a$ and $R$. These exponential behaviors may account for the dynamical compactification of extra dimensions and the accelerating expansion of the 4-dimensional universe in terms of Hubble parameter, $H$. The accelerat...
Ghosh, Kirtiman; Huitu, Katri
2012-06-01
We discuss the collider phenomenology of Universal Extra Dimension models with gravity mediated decays. We concentrate on diphoton associated with large missing transverse energy signature. At the collider, level-1 Kaluza-Klein (KK) particles are produced in pairs due to the conservation of KK-parity. Subsequently, KK-particles decay via cascades involving lighter KK-particles until reaching the lightest KK-particle (LKP). Finally, gravity induced decay of the LKP into photons gives rise to the diphoton signature. The search for diphoton events with large missing transverse energy was recently communicated by the ATLAS collaboration for 7 TeV center-of-mass energy and 3.1 inverse femtobarn integrated luminosity of the Large Hadron Collider. Above the Standard Model background prediction, no excess of such events was reported. We translate the absence of any excess of the diphoton events to constrain the model parameters, namely, the radius of compactification ( R) and the fundamental Planck mass ( M D ).
Ghosh, Kirtiman
2012-01-01
We discuss the collider phenomenology of Universal Extra Dimension models with gravity mediated decays. We concentrate on diphoton associated with large missing transverse energy signature. At the collider, level-1 Kaluza-Klein (KK) particles are produced in pairs due to the conservation of KK-parity. Subsequently, KK-particles decay via cascades involving lighter KK-particles until reaching the lightest KK-particle (LKP). Finally, gravity induced decay of the LKP into photons gives rise to the diphoton signature. The search for diphoton events with large missing transverse energy was recently communicated by the ATLAS collaboration for 7 TeV center-of-mass energy and 3.1 inverse femtobarn integrated luminosity of the Large Hadron Collider. Above the Standard Model background prediction, no excess of such events was reported. We translate the absence of any excess of the diphoton events to constrain the model parameters, namely, the radius of compactification (R) and the fundamental Planck mass ($M_D$).
Associated Productions of HZZ and HHZ at Linear Colliders in Large Extra Dimension Model
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
In this paper we investigate the effects of the large extra dimensions on the two processes e+ e → H0 Z0 Z0 and e+e- → H0H0Z0 at linear colliders in both unpolarized and polarized collision modes. We find that the virtual Kaluza-Klein graviton exchange can significantly enhance the cross section from their standard model expectations for these two processes. The results show that the LED effect on the process e+ e- → H0 Z0 Z0 allows the observation limits on the effective scale Ms to be probed up to 9.75 TeVand 10.1 TeV in the unpolarized and +-(λe+ = 1/2, λe- = -1/2) polarized beam collision modes (with Pe+ = 0.6, Pe- = 0.8), respectively. For the process e+ e- → H0 H0 Z0, these limits on Ms can be probed up to 6.06 TeV and 6.38 TeV in the unpolarized and polarized collision modes separately. We find that the λe+ = 1/2, λe- = -1/2 polarization collision mode in both process e+e- → H0Z0Z0 and e+e- → H0H0Z0 may provide a possibility to improve the sensitivity in probing the LED effects.
Gravitational wave source counts at high redshift and in models with extra dimensions
García-Bellido, Juan; Trashorras, Manuel
2016-01-01
Gravitational wave (GW) source counts have been recently shown to be able to test how gravitational radiation propagates with the distance from the source. Here, we extend this formalism to cosmological scales, i.e. the high redshift regime, and we also allow for models with large or compactified extra dimensions like in the Kaluza-Klein (KK) model. We found that in the high redshift regime one would potentially expect two windows where observations above the minimum signal-to-noise threshold can be made, assuming there are no higher order corrections in the redshift dependence of the signal-to-noise $S/N(z)$ for the expected prediction. Furthermore, we also considered the case of intermediate redshifts, i.e. $0
$ZZW$ production at the LHC within large extra dimensions model in next-to-leading order QCD
Chong, Chen; Wen-Gan, Ma; Ren-You, Zhang; Xiao-Zhou, Li; Yu, Zhang
2014-01-01
We investigate the large extra dimensions (LED) effects induced by the Kaluza-Klein gravitons up to the QCD next-to-leading order (NLO) on the $ZZW$ production at the large hardron collider (LHC). The integrated cross sections and some kinematic distributions are presented in both the standard model (SM) and the LED model. Our results show that the leading order (LO) relative deviations between the predictions in the LED model and the SM are significant, especially in the large $M_{ZZ}$ region, large $p_T$ and the central rapidity regions of the final products separately, while the NLO QCD corrections remarkably reduce the relative LED deviations. We find that if we take $M_S=4.8~{\\rm TeV}$, $d=3$, and adopt the event selection scheme with $M_{ZZ}>500~{\\rm GeV}$, $p_T^{Z}>100~{\\rm GeV}$ and $p_T^{W}>20~{\\rm GeV}$, the LO (NLO) relative deviations at the $14~{\\rm TeV}$ LHC increase to $19.8 \\%$ ($8.05\\%$) and $12.30\\%$ ($5.63\\%$) for the $ZZW^+$ and $ZZW^-$ productions, respectively. We also see that with the ...
Kaluza-Klein reduction of massive and partially massless spin-2 fields
Bonifacio, James; Hinterbichler, Kurt
2017-01-01
We describe the dimensional reduction of massive and partially massless spin-2 fields on general Einstein direct product manifolds. As with massless fields, the higher-dimensional gauge symmetry of the partially massless field displays itself upon dimensional reduction as a tower of Stückelberg symmetries for the massive modes of the tower. Unlike the massless case, the zero mode of the gauge symmetry does not display itself as a lower-dimensional non-Stückelberg gauge symmetry enforcing partial masslessness on the zero mode. Partial masslessness is destroyed by the dimensional reduction and the zero-mode gauge symmetry instead serves to eliminate the radion. In addition, we study the fully nonlinear dimensional reduction of de Rham-Gabadadze-Tolley massive gravity on a circle, which results in a massive scalar-tensor-vector theory which we expect to be ghost free, and whose scalar-tensor sector is a special case of mass-varying massive gravity.
Standard cosmological evolution in the f(R) model to Kaluza-Klein cosmology
Energy Technology Data Exchange (ETDEWEB)
Aghmohammadi, A; Abolhassani, M R [Plasma Physics Research Center, Science and Research Branch, Islamic Azad University of Tehran (Iran, Islamic Republic of); Saaidi, Kh; Vajdi, A [Department of Physics, Faculty of Science, University of Kurdistan, Pasdaran Ave., Sanandaj (Iran, Islamic Republic of)], E-mail: agha35484@yahoo.com, E-mail: ksaaidi@uok.ac.ir, E-mail: mrhasani@modares.ac.ir, E-mail: Avajdi@uok.ac.ir
2009-12-15
In this paper, using f(R) theory of gravity we explicitly calculate cosmological evolution in the presence of a perfect fluid source in four- and five-dimensional space-time in which this cosmological evolution in self-creation is presented by Reddy et al (2009 Int. J. Theor. Phys. 48 10). An exact cosmological model is presented using a relation between Einstein's gravity field equation components due to a metric with the same component from f(R) theory of gravity. Some physics and kinematical properties of the model are also discussed.
Gauge invariance, quantization and integration of heavy modes in a gauge Kaluza-Klein theory
Novales-Sánchez, H.
This dissertation examines topics at the intersection of environmental and energy economics. The first two chapters explore how policies can induce more efficient use of the energy sources available for generating electricity. The electricity sector is a major source of a wide variety of harmful pollutants. To mitigate the environmental impacts of electricity production, a variety of policies are being implemented to increase the quantity of generation from clean, renewable energy sources. The first chapter identifies the short-run reductions in emissions caused by generation from a particular renewable technology; wind turbines. Using the estimates of the pollution offset by the renewable production, I explore the efficiency of the incentives created by the current set of renewable energy policies. The second chapter examines the impact adding bulk electricity storage capacity will have on the full social costs of generating electricity. The third chapter explores the impact of various gasoline tax structures on both retail price volatility and state revenue volatility.
Kaluza-Klein Theory as a Dynamics in a Dual Geometry
Gershon, Avi
2009-01-01
It has been shown that the orbits of motion for a wide class of non-relativistic Hamiltonian systems can be described as geodesic flow on a manifold and an associated dual. This method can be applied to a four dimensional manifold of orbits in space-time associated with a relativistic system. One can study the consequences on the geometry of the introduction of electromagnetic interaction. We find that resulting geometrical structure in the dual space is that of Kaluza and Klein.
Tunnelling of scalar and Dirac particles from squashed charged rotating Kaluza-Klein black holes
Energy Technology Data Exchange (ETDEWEB)
Stetsko, M.M. [Ivan Franko National University of Lviv, Department of Theoretical Physics, Lviv (Ukraine)
2016-02-15
The thermal radiation of scalar particles and Dirac fermions from squashed charged rotating five-dimensional black holes is considered. To obtain the temperature of the black holes we use the tunnelling method. In the case of scalar particles we make use of the Hamilton-Jacobi equation. To consider tunnelling of fermions the Dirac equation was investigated. The examination shows that the radial parts of the action for scalar particles and fermions in the quasi-classical limit in the vicinity of horizon are almost the same and as a consequence it gives rise to identical expressions for the temperature in the two cases. (orig.)
Tunnelling of scalar and Dirac particles from squashed charged rotating Kaluza-Klein black holes
Stetsko, M. M.
2016-02-01
The thermal radiation of scalar particles and Dirac fermions from squashed charged rotating five-dimensional black holes is considered. To obtain the temperature of the black holes we use the tunnelling method. In the case of scalar particles we make use of the Hamilton-Jacobi equation. To consider tunnelling of fermions the Dirac equation was investigated. The examination shows that the radial parts of the action for scalar particles and fermions in the quasi-classical limit in the vicinity of horizon are almost the same and as a consequence it gives rise to identical expressions for the temperature in the two cases.
Kaluza-Klein Reduction of Massive and Partially Massless Spin-2
Bonifacio, James
2016-01-01
We describe the dimensional reduction of massive and partially massless spin-2 fields on general Einstein direct product manifolds. As with massless fields, the higher-dimensional gauge symmetry of the partially massless field displays itself upon dimensional reduction as a tower of St\\"uckelberg symmetries for the massive modes of the tower. Unlike the massless case, the zero mode of the gauge symmetry does not display itself as a lower-dimensional non-Stuckelberg gauge symmetry enforcing partial masslessness on the zero mode. Partial masslessness is destroyed by the dimensional reduction and the zero mode gauge symmetry instead serves to eliminate the radion. In addition, we study the fully non-linear dimensional reduction of dRGT massive gravity on a circle, which results in a massive scalar-tensor-vector theory which we expect to be ghost-free, and whose scalar-tensor sector is a special case of mass-varying massive gravity.
Einstein-Yang-Mills-Dirac systems from the discretized Kaluza-Klein theory
Nguyen, Ai Viet; Nguyen, Suan Han; Wali, Kameshwar C
2016-01-01
A unified theory of the non-Abelian gauge interactions with gravity in the framework of a discretized Kaluaza-Kleine theory is constructed with a modified Dirac operator and wedge product. All the couplings of chiral spinors to the non-Abelian gauge fields emerge naturally as components of the couplings of the chiral spinors to the generalized gravity together with some new interactions. In particular, the currently prevalent gravity-QCD-quark and gravity-electroweak-quark-lepton models are shown to follow as special cases of the general framework.
Gravitational wave source counts at high redshift and in models with extra dimensions
García-Bellido, Juan; Nesseris, Savvas; Trashorras, Manuel
2016-07-01
Gravitational wave (GW) source counts have been recently shown to be able to test how gravitational radiation propagates with the distance from the source. Here, we extend this formalism to cosmological scales, i.e. the high redshift regime, and we discuss the complications of applying this methodology to high redshift sources. We also allow for models with compactified extra dimensions like in the Kaluza-Klein model. Furthermore, we also consider the case of intermediate redshifts, i.e. 0 < z lesssim 1, where we show it is possible to find an analytical approximation for the source counts dN/d(S/N). This can be done in terms of cosmological parameters, such as the matter density Ωm,0 of the cosmological constant model or the cosmographic parameters for a general dark energy model. Our analysis is as general as possible, but it depends on two important factors: a source model for the black hole binary mergers and the GW source to galaxy bias. This methodology also allows us to obtain the higher order corrections of the source counts in terms of the signal-to-noise S/N. We then forecast the sensitivity of future observations in constraining GW physics but also the underlying cosmology by simulating sources distributed over a finite range of signal-to-noise with a number of sources ranging from 10 to 500 sources as expected from future detectors. We find that with 500 events it will be possible to provide constraints on the matter density parameter at present Ωm,0 on the order of a few percent and with the precision growing fast with the number of events. In the case of extra dimensions we find that depending on the degeneracies of the model, with 500 events it may be possible to provide stringent limits on the existence of the extra dimensions if the aforementioned degeneracies can be broken.
Limits on large extra dimensions based on observations of neutron stars with the Fermi-LAT
Energy Technology Data Exchange (ETDEWEB)
Ajello, M.; Bechtol, K.; Berenji, B.; Bloom, E.D.; Borgland, A.W.; Buehler, R.; Cameron, R.A. [W.W. Hansen Experimental Physics Laboratory, Kavli Institute for Particle Astrophysics and Cosmology, Department of Physics and SLAC National Accelerator Laboratory, Stanford University, Stanford, CA 94305 (United States); Baldini, L.; Bellazzini, R.; Bregeon, J. [INFN — Sezione di Pisa, I-56127 Pisa (Italy); Barbiellini, G. [INFN — Sezione di Trieste, I-34127 Trieste (Italy); Bastieri, D.; Buson, S. [INFN — Sezione di Padova, I-35131 Padova (Italy); Bonamente, E.; Cecchi, C. [INFN — Sezione di Perugia, I-06123 Perugia (Italy); Brigida, M. [Dipartimento di Fisica ' M. Merlin' dell' Università e del Politecnico di Bari, I-70126 Bari (Italy); Bruel, P. [Laboratoire Leprince-Ringuet, École polytechnique, CNRS/IN2P3, Palaiseau (France); Caliandro, G.A. [Institut de Ciències de l' Espai (IEEE-CSIC), Campus UAB, 08193 Barcelona (Spain); Caraveo, P.A. [INAF-Istituto di Astrofisica Spaziale e Fisica Cosmica, I-20133 Milano (Italy); Casandjian, J.M., E-mail: bijanb@alumni.stanford.edu, E-mail: elliott@slac.stanford.edu, E-mail: johann.cohen-tanugi@lupm.in2p3.fr [Laboratoire AIM, CEA-IRFU/CNRS/Université Paris Diderot, Service d' Astrophysique, CEA Saclay, 91191 Gif sur Yvette (France); Collaboration: Fermi-LAT collaboration; and others
2012-02-01
We present limits for the compactification scale in the theory of Large Extra Dimensions (LED) proposed by Arkani-Hamed, Dimopoulos, and Dvali. We use 11 months of data from the Fermi Large Area Telescope (Fermi-LAT) to set gamma ray flux limits for 6 gamma-ray faint neutron stars (NS). To set limits on LED we use the model of Hannestad and Raffelt (HR) that calculates the Kaluza-Klein (KK) graviton production in supernova cores and the large fraction subsequently gravitationally bound around the resulting NS. The predicted decay of the bound KK gravitons to γγ should contribute to the flux from NSs. Considering 2 to 7 extra dimensions of the same size in the context of the HR model, we use Monte Carlo techniques to calculate the expected differential flux of gamma-rays arising from these KK gravitons, including the effects of the age of the NS, graviton orbit, and absorption of gamma-rays in the magnetosphere of the NS. We compare our Monte Carlo-based differential flux to the experimental differential flux using maximum likelihood techniques to obtain our limits on LED. Our limits are more restrictive than past EGRET-based optimistic limits that do not include these important corrections. Additionally, our limits are more stringent than LHC based limits for 3 or fewer LED, and comparable for 4 LED. We conclude that if the effective Planck scale is around a TeV, then for 2 or 3 LED the compactification topology must be more complicated than a torus.
Limits on Large Extra Dimensions Based on Observations of Neutron Stars with the Fermi-LAT
Energy Technology Data Exchange (ETDEWEB)
Ajello, M.; /SLAC /KIPAC, Menlo Park; Baldini, L.; /INFN, Pisa; Barbiellini, G.; /INFN, Trieste /Trieste U.; Bastieri, D.; /INFN, Padua /Padua U.; Bechtol, K.; /SLAC /KIPAC, Menlo Park; Bellazzini, R.; /INFN, Pisa; Berenji, B.; /SLAC /KIPAC, Menlo Park; Bloom, E.D.; /SLAC /KIPAC, Menlo Park; Bonamente, E.; /INFN, Perugia /Perugia U.; Borgland, A.W.; /SLAC /KIPAC, Menlo Park; Bregeon, J.; /INFN, Pisa; Brigida, M.; /Bari Polytechnic /INFN, Bari; Bruel, P.; /Ecole Polytechnique; Buehler, R.; /SLAC /KIPAC, Menlo Park; Buson, S.; /INFN, Padua /Padua U.; Caliandro, G.A.; /CSIC, Catalunya; Cameron, R.A.; /SLAC /KIPAC, Menlo Park; Caraveo, P.A.; /Brera Observ.; Casandjian, J.M.; /AIM, Saclay; Cecchi, C.; /INFN, Perugia /Perugia U.; Charles, E.; /SLAC /KIPAC, Menlo Park /Naval Research Lab, Wash., D.C. /SLAC /KIPAC, Menlo Park /ASDC, Frascati /Perugia U. /SLAC /KIPAC, Menlo Park /Montpellier U. /Stockholm U. /Stockholm U., OKC /Royal Swedish Acad. Sci. /ASDC, Frascati /Udine U. /INFN, Trieste /Bari Polytechnic /INFN, Bari /Naval Research Lab, Wash., D.C. /SLAC /KIPAC, Menlo Park /SLAC /KIPAC, Menlo Park /SLAC /KIPAC, Menlo Park /SLAC /KIPAC, Menlo Park /Bari Polytechnic /INFN, Bari /Ecole Polytechnique /NASA, Goddard /Hiroshima U. /Bari Polytechnic /INFN, Bari /INFN, Bari /ASDC, Frascati /INFN, Perugia /Perugia U. /Bari Polytechnic /INFN, Bari /Bari Polytechnic /INFN, Bari /Bologna Observ. /SLAC /KIPAC, Menlo Park /SLAC /KIPAC, Menlo Park /SLAC /KIPAC, Menlo Park /AIM, Saclay /Alabama U., Huntsville /INFN, Padua; /more authors..
2012-08-17
We present limits for the compactification scale in the theory of Large Extra Dimensions (LED) proposed by Arkani-Hamed, Dimopoulos, and Dvali. We use 11 months of data from the Fermi Large Area Telescope (Fermi-LAT) to set gamma ray flux limits for 6 gamma-ray faint neutron stars (NS). To set limits on LED we use the model of Hannestad and Raffelt (HR) that calculates the Kaluza-Klein (KK) graviton production in supernova cores and the large fraction subsequently gravitationally bound around the resulting NS. The predicted decay of the bound KK gravitons to {gamma}{gamma} should contribute to the flux from NSs. Considering 2 to 7 extra dimensions of the same size in the context of the HR model, we use Monte Carlo techniques to calculate the expected differential flux of gamma-rays arising from these KK gravitons, including the effects of the age of the NS, graviton orbit, and absorption of gamma-rays in the magnetosphere of the NS. We compare our Monte Carlo-based differential flux to the experimental differential flux using maximum likelihood techniques to obtain our limits on LED. Our limits are more restrictive than past EGRET-based optimistic limits that do not include these important corrections. Additionally, our limits are more stringent than LHC based limits for 3 or fewer LED, and comparable for 4 LED. We conclude that if the effective Planck scale is around a TeV, then for 2 or 3 LED the compactification topology must be more complicated than a torus.
Natural Dirac Neutrinos from Warped Extra Dimension
Wu, Jackson M S
2010-01-01
Dirac neutrinos arising from gauged discrete symmetry \\`a la Krauss-Wilczek are implemented in the minimal custodial Randall-Sundrum model. In the case of a normal hierarchy, all lepton masses and mixing pattern can be naturally reproduced at the TeV scale set by the electroweak constraints, while simultanously satisfy bounds from lepton flavour violation. A nonzero neutrino mixing angle, $\\theta_{13}$, is generic in the scenario, as well as the existence of sub-TeV right-handed Kaluza-Klein neutrinos, which may be searched for at the LHC.
Peng, Jun-Jin
2016-01-01
In this paper, we investigate the conserved charges of generally diffeomorphism invariant gravity theories with a wide variety of matter fields, particularly of the theories with multiple scalar fields and $p$-form potentials, in the context of the off-shell generalized Abbott-Deser-Tekin (ADT) formalism. We first construct a new off-shell ADT current that consists of the terms for the variation of a Killing vector and expressions of the field equations as well as the Lie derivative of a surface term with respect to the Killing vector within the framework of generally diffeomorphism invariant gravity theories involving various matter fields. After deriving the off-shell ADT potential corresponding to this current, we propose a formula of conserved charges for these theories due to the potential. Next, we derive the off-shell ADT potential associated with the generic Lagrangian that describes a large range of gravity theories with a number of scalar fields and $p$-form potentials. Finally, the properties of th...
Effect of Self-Interaction on Vacuum Energy for Yang-Mills System in Kaluza-Klein Theory
Shiraishi, Kiyoshi
2015-01-01
We calculate the vacuum energy for Yang--Mills (YM) system in the background space-time $M^4 \\times S^3$, taking the effect of self-interaction of the YM fields into account. The compactification scale obtained by Candelas--Weinberg mechanism becomes large if the YM coupling is large. The case with an extra space $S^3/Z_2$ is also considered, and it is shown that the vacuum associated with broken gauge symmetry is unstable.
Yazadjiev, S
2012-01-01
We present a new solution in 5D Einstein-Maxwell-dilaton gravity describing an equilibrium configuration of extremal rotating black holes with lens space horizon topologies. The basic properties of the solution are investigated and the basic physical quantities are calculated. It is shown that the black hole horizons are superconducting in the sense that they expel the magnetic flux lines.
Saharian, Aram; Kotanjyan, Anna; Sargsyan, Hayk; Simonyan, David
2016-07-01
The models with compact spatial dimensions appear in a number of fundamental physical theories. In particular, the idea of compactified dimensions has been extensively used in supergravity and superstring theories. In quantum field theory, the modification of the vacuum fluctuations spectrum by the periodicity conditions imposed on the field operator along compact dimensions leads to a number of interesting physical effects. A well known example of this kind, demonstrating the close relation between quantum phenomena and global geometry, is the topological Casimir effect. In models with extra compact dimensions, the Casimir energy creates a nontrivial potential for the compactification radius. This can serve as a stabilization mechanism for moduli fields and for the effective gauge couplings. The Casimir effect has also been considered as a possible origin for the dark energy in Kaluza-Klein-type and braneworld models. In the resent presentation we investigate the effects of the gravity and topology on the local properties of the quantum vacuum for a charged scalar field in the presence of a classical gauge field. Vacuum expectation value of the energy-momentum tensor and current density are investigated for a charged scalar field in dS spacetime with toroidally compact spatial dimensions in the presence of a classical constant gauge field. Due to the nontrivial topology, the latter gives rise to Aharonov-Bohm-like effect on the vacuum characteristics. The vacuum current density, energy density and stresses are even periodic functions of the magnetic flux enclosed by compact dimensions. For small values of the comoving lengths of compact dimensions, compared with the dS curvature radius, the effects of gravity on the topological contributions are small and the expectation values are expressed in terms of the corresponding quantities in the Minkowski bulk by the standard conformal relation. For large values of the comoving lengths, depending on the field mass, two
Energy Technology Data Exchange (ETDEWEB)
Albrecht, Michaela E.
2010-08-16
The minimal-flavour-violating (MFV) hypothesis considers the Standard Model (SM) Yukawa matrices as the only source of flavour violation. In this work, we promote their entries to dynamical scalar spurion fields, using an effective field theory approach, such that the maximal flavour symmetry (FS) of the SM gauge sector is formally restored at high energy scales. The non-vanishing vacuum expectation values of the spurions induce a sequence of FS breaking and generate the observed hierarchy in the SM quark masses and mixings. The fact that there exists no explanation for it in the SM is known as the flavour puzzle. Gauging the non-abelian subgroup of the spontaneously broken FS, we interpret the associated Goldstone bosons as the longitudinal degrees of freedom of the corresponding massive gauge bosons. Integrating out the heavy Higgs modes in the Yukawa spurions leads directly to flavour-changing neutral currents (FCNCs) at tree level. The coefficients of the effective four-quark operators, resulting from the exchange of heavy flavoured gauge bosons, strictly follow the MFV principle. On the other hand, the Goldstone bosons associated with the global abelian symmetry group behave as weakly coupled axions which can be used to solve the strong CP problem within a modified Peccei-Quinn formalism. Models with a warped fifth dimension contain five-dimensional (5D) fermion bulk mass matrices in addition to their 5D Yukawa matrices, which thus represent an additional source of flavour violation beyond MFV. They can address the flavour puzzle since their eigenvalues allow for a different localisation of the fermion zero mode profiles along the extra dimension which leads to a hierarchy in the effective four-dimensional (4D) Yukawa matrices. At the same time, the fermion splitting introduces non-universal fermion couplings to Kaluza-Klein (KK) gauge boson modes, inducing tree-level FCNCs. Within a Randall-Sundrum model with custodial protection (RSc model) we carefully work
SO(10) GUT in Four and Five Dimensions: a Review
Fukuyama, Takeshi
2013-04-01
transmitted to the PS brane through the gaugino mediation with bulk gauge multiplet. Further breaking of the PS gauge group to the SM group is realized by VEVs of the Higgs multiplets (4, 1, 2) ⊕ (\\bar {4}, 1, 2). We show that this model not only cures all pathologies in SO(10) GUT in 4D but also provides the consistent inflation scenario and dark matter candidate and leptogenesis. The gauge coupling unification is successfully realized after incorporating the threshold corrections of the Kaluza-Klein modes. Finally we add some comments on the impacts of the discovery of a Higgs-like particle by the Large Hadronic Collider at CERN (LHC) on SUSY GUTs.
Extremal Static AdS Black Hole/CFT Correspondence in Gauged Supergravities
Lü, H; Pope, C N; Vazquez-Poritz, J
2009-01-01
A recently proposed holographic duality allows the Bekenstein-Hawking entropy of extremal rotating black holes to be calculated microscopically, by applying the Cardy formula to the two-dimensional chiral CFTs associated with certain reparameterisations of azimuthal angular coordinates in the solutions. The central charges are proportional to the angular momenta of the black hole, and so the method degenerates in the case of static (non-rotating) black holes. We show that the method can be extended to encompass such charged static extremal AdS black holes by using consistent Kaluza-Klein sphere reduction ansatze to lift them to exact solutions in the low-energy limits of string theory or M-theory, where the electric charges become reinterpreted as angular momenta associated with internal rotations in the reduction sphere. We illustrate the procedure for the examples of extremal charged static AdS black holes in four, five, six and seven dimensions.
Representation and Dimensional Reduction of the Universe
Institute of Scientific and Technical Information of China (English)
吴忠超
2004-01-01
The external space we live in or the apparent dimension in the Kaluza-Klein model can be identified by using the right representation in quantum cosmology. The external dimension of the Freund-Rubin model is min(s, n - s),where s is the rank of the antisymmetric field strength in the model.
Energy Technology Data Exchange (ETDEWEB)
Micheli, Fiorenza de [Centro de Estudios Cientificos, Arturo Prat 514, Valdivia (Chile); Instituto de Fisica, Pontificia Universidad Catolica de Valparaiso, Casilla 4059, Valparaiso (Chile); Zanelli, Jorge [Centro de Estudios Cientificos, Arturo Prat 514, Valdivia (Chile); Universidad Andres Bello, Av. Republica 440, Santiago (Chile)
2012-10-15
A degenerate dynamical system is characterized by a symplectic structure whose rank is not constant throughout phase space. Its phase space is divided into causally disconnected, nonoverlapping regions in each of which the rank of the symplectic matrix is constant, and there are no classical orbits connecting two different regions. Here the question of whether this classical disconnectedness survives quantization is addressed. Our conclusion is that in irreducible degenerate systems-in which the degeneracy cannot be eliminated by redefining variables in the action-the disconnectedness is maintained in the quantum theory: there is no quantum tunnelling across degeneracy surfaces. This shows that the degeneracy surfaces are boundaries separating distinct physical systems, not only classically, but in the quantum realm as well. The relevance of this feature for gravitation and Chern-Simons theories in higher dimensions cannot be overstated.
Monopole in the dilatonic gauge field theory
Karczewska, D
2000-01-01
A numerical study of coupled to the dilaton field, static, spherically symmetric monopole solutions inspired by the Kaluza-Klein theory with large extra dimensions are presented. The generalized Prasad-Sommerfield solution is obtained. We show that monopole may have also the dilaton cloud configurations.
Consistent truncations with massive modes and holography
Cassani, Davide; Faedo, Anton F
2011-01-01
We review the basic features of some recently found consistent Kaluza-Klein truncations including massive modes. We emphasize the general ideas underlying the reduction procedure, then we focus on type IIB supergravity on 5-dimensional manifolds admitting a Sasaki-Einstein structure, which leads to half-maximal gauged supergravity in five dimensions. Finally, we comment on the holographic picture of consistency.
Emergent of non-gravitational fields in dimensional reduction of 4d spin foam models
Fani, Somayeh
2011-01-01
We consider a Kaluza-Klein like approach for a 4d spin foam model. We apply this approach to a 4d TOCY model based on group field theory; and using the Peter-Weyl expansion of the gravitational field we will find a mechanism for gen- eration of matter and new dimensions from pure gravity.
Maeda-Dadhich Solutions as Real Black Holes
Alexeyev, S. O.; Petrov, A. N.; Latosh, B. N.
2016-10-01
A four-dimensional static Schwarzschild-like solutions obtained in [4, 5] in the frames of the Einstein-Gauss-Bonnet gravity at the Kaluza-Klein split are analyzed. In such models matter is created by auxiliary dimensions. The main goal of our work is to check that these solutions are physically sensible, and to examine their characteristics, which could be observable.
Smolyakov, Mikhail N
2015-01-01
In the present paper we discuss some problems which arise, when the matter, gauge and Higgs fields are allowed to propagate in the bulk of five-dimensional brane world models with compact extra dimension and their zero Kaluza-Klein modes are supposed to exactly reproduce the Standard Model fields and their interactions.
Fermions in five-dimensional brane world models
Energy Technology Data Exchange (ETDEWEB)
Smolyakov, Mikhail N. [Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University,119991, Moscow (Russian Federation)
2016-06-28
In the present paper the fermion fields, living in the background of five-dimensional warped brane world models with compact extra dimension, are thoroughly examined. The Kaluza-Klein decomposition and isolation of the physical degrees of freedom is performed for those five-dimensional fermion field Lagrangians, which admit such a decomposition to be performed in a mathematically consistent way and provide a physically reasonable four-dimensional effective theory. It is also shown that for the majority of five-dimensional fermion field Lagrangians there are no (at least rather obvious) ways to perform the Kaluza-Klein decomposition consistently. Moreover, in these cases one may expect the appearance of various pathologies in the four-dimensional effective theory. Among the cases, for which the Kaluza-Klein decomposition can be performed in a mathematically consistent way, the case, which reproduces the Standard Model by the zero Kaluza-Klein modes most closely regardless of the size of the extra dimension, is examined in detail in the background of the Randall-Sundrum model.
Fermions in five-dimensional brane world models
Smolyakov, Mikhail N
2016-01-01
In the present paper the fermion fields, living in the background of five-dimensional warped brane world models with compact extra dimension, are thoroughly examined. The Kaluza-Klein decomposition and isolation of the physical degrees of freedom is performed for those five-dimensional fermion field Lagrangians, which admit such a decomposition to be performed in a mathematically consistent way and provide a physically reasonable four-dimensional effective theory. It is also shown that for the majority of five-dimensional fermion field Lagrangians there are no (at least rather obvious) ways to perform the Kaluza-Klein decomposition consistently. Moreover, in these cases one may expect the appearance of various pathologies in the four-dimensional effective theory. Among the cases, for which the Kaluza-Klein decomposition can be performed in a mathematically consistent way, the case, which reproduces the Standard Model by the zero Kaluza-Klein modes most closely regardless of the size of the extra dimension, is...
Fermions in five-dimensional brane world models
Smolyakov, Mikhail N.
2016-06-01
In the present paper the fermion fields, living in the background of five-dimensional warped brane world models with compact extra dimension, are thoroughly examined. The Kaluza-Klein decomposition and isolation of the physical degrees of freedom is performed for those five-dimensional fermion field Lagrangians, which admit such a decomposition to be performed in a mathematically consistent way and provide a physically reasonable four-dimensional effective theory. It is also shown that for the majority of five-dimensional fermion field Lagrangians there are no (at least rather obvious) ways to perform the Kaluza-Klein decomposition consistently. Moreover, in these cases one may expect the appearance of various pathologies in the four-dimensional effective theory. Among the cases, for which the Kaluza-Klein decomposition can be performed in a mathematically consistent way, the case, which reproduces the Standard Model by the zero Kaluza-Klein modes most closely regardless of the size of the extra dimension, is examined in detail in the background of the Randall-Sundrum model.
Constraints on gauge-Higgs unification models at the LHC
Kitazawa, Noriaki
2015-01-01
We examine the possibility of observing the Kaluza-Klein gluons in gauge-Higgs unification models at the LHC with the energy sqrt{s}=14 TeV. We consider a benchmark model with the gauge symmetry SU(3)_C x SU(3)_W in five-dimensional space-time, where SU(3)_C is the gauge symmetry of the strong interaction and SU(3)_W is that for the electroweak interaction and a Higgs doublet field. It is natural in general to introduce SU(3)_C gauge symmetry in five-dimensional space-time as well as SU(3)_W gauge symmetry in gauge-Higgs unification models. Since the fifth dimension is compactified to S1/Z2 orbifold, there are Kaluza-Klein modes of gluons in low-energy effective theory in four-dimensional space-time. We investigate the resonance contribution of the first Kaluza-Klein gluon to dijet invariant mass distribution at the LHC, and provide signal-to-noise ratios in various cases of Kaluza-Klein gluon masses and kinematical cuts. Although the results are given in a specific benchmark model, we discuss their applicati...
Running of soft parameters in extra space-time dimensions
Energy Technology Data Exchange (ETDEWEB)
Kobayashi, Tatsuo; Kubo, Jisuke; Mondragon, Myriam; Zoupanos, George
1999-06-14
The evolution of the parameters including those in the soft supersymmetry-breaking (SSB) sector is studied in the minimal supersymmetric standard model (MSSM) with a certain set of Kaluza-Klein towers which has been recently considered by Dienes et al. We use the continuous Wilson renormalization group technique to derive the one-loop matching condition between the effective, renormalizable and original, unrenormalizable theories. We investigate whether the assumption of a large compactification radius in the model is consistent with the gauge coupling unification, the b-{tau} unification and the radiative breaking of the electroweak gauge symmetry with the universal SSB terms. We calculate the superpartner spectrum under the assumption of the universal SSB parameters to find differences between the model and the MSSM.
[Hepatolenticular degeneration].
Zudenigo, D; Relja, M
1990-01-01
Hepatolenticular degeneration (Wilson's disease) is a hereditary disease in which metabolic disorder of copper leads to its accumulation in the liver, brain, cornea and kidneys with consequent pathologic changes in those organs. Hereditary mechanism of the disease is autosomal recessive with prevalence of 30-100 per 1,000,000 inhabitants. Etiology of this disease is not yet explained. There are two hypotheses. The first one is that it is the disorder of ceruloplasmine metabolism caused by insufficient synthesis of normal ceruloplasmine, or synthesis of functionally abnormal ceruloplasmine. The second one is: the block of copper biliar excretion which is the consequence of the liver lysosomes functional defect. Pathogenetic mechanism of disease is firstly long-term accumulation of copper in the liver, and later, when the liver depo is full, its releasing in circulation and accumulation in the brain, cornea, kidneys and bones, which causes adequate pathologic changes. Toxic activity of copper is the consequence of its activity on enzymes, particularly on those with -SH group. There are two basic clinical forms of the disease: liver disease or neurologic disease. Before puberty the liver damage is more frequent, while in adolescents and young adults neurologic form of the disease is usual. The liver disease is nonspecific and characterized by symptoms of cirrhosis and chronic aggressive hepatitis. The only specificity is hemolytic anemia which, in combination with previous symptoms, is important for diagnosis of the disease. Neurologic symptoms are the most frequent consequence of pathologic changes in the basal ganglia. In our patients the most frequent symptoms were tremor (63%); dysarthria, choreoathetosis and rigor (38%); ataxia and mental disorders (31%); dysphagia and dystonia (12%), diplopia, hypersalivation, nystagmus and Babinski's sign (6%). Among pathologic changes in other tissues and organs the most important is the finding of Kayser-Fleischer ring in the
Institute of Scientific and Technical Information of China (English)
韩毅昂; 郭宗宽
2001-01-01
在五维黎曼流形基础上,将K1ein-Gordon标量场方程由最小耦合情况推广到共形耦合情况,并深入讨论了质量相对变化率,结果表明:在静态球对称解和Friedman宇宙学解下检验粒子的四维有效质量是可变的.
Non-autonomous Degenerate KdV Systems
Turhan, Refik
2002-01-01
Non-autonomous degenerate KdV systems in (1+1) dimensions are considered for integrability classification. Integrability of the systems is associated with the existence of a recursion operator. Some new non-autonomous degenerate two-component KdV systems are found.
... macular degeneration Overview By Mayo Clinic Staff Wet macular degeneration is a chronic eye disease that causes blurred vision or a blind spot in your visual field. It's generally caused by abnormal blood vessels that leak fluid or blood into ... macular degeneration is one of two types of age-related ...
Nonunital Spectral Triples Associated to Degenerate Metrics
Rennie, A.
We show that one can define (p,∞)-summable spectral triples using degenerate metrics on smooth manifolds. Furthermore, these triples satisfy Connes-Moscovici's discrete and finite dimension spectrum hypothesis, allowing one to use the Local Index Theorem [1] to compute the pairing with K-theory. We demonstrate this with a concrete example.
On the quasi-linearity of the Einstein- "Gauss-Bonnet" gravity field equations
Deruelle, N; Deruelle, Nathalie; Madore, John
2003-01-01
We review some properties of the Einstein-"Gauss-Bonnet" equations for gravity--also called the Einstein-Lanczos equations in five and six dimensions, and the Lovelock equations in higher dimensions. We illustrate, by means of simple Kaluza-Klein and brane cosmological models, some consequences of the quasi-linearity of these equations on the Cauchy problem and structure of characteristics (a point first studied by Yvonne Choquet-Bruhat), as well as on "junction conditions".
Degenerate Euler zeta function
Kim, Taekyun
2015-01-01
Recently, T. Kim considered Euler zeta function which interpolates Euler polynomials at negative integer (see [3]). In this paper, we study degenerate Euler zeta function which is holomorphic function on complex s-plane associated with degenerate Euler polynomials at negative integers.
Phase space methods for degenerate quantum gases
Dalton, Bryan J; Barnett, Stephen M
2015-01-01
Recent experimental progress has enabled cold atomic gases to be studied at nano-kelvin temperatures, creating new states of matter where quantum degeneracy occurs - Bose-Einstein condensates and degenerate Fermi gases. Such quantum states are of macroscopic dimensions. This book presents the phase space theory approach for treating the physics of degenerate quantum gases, an approach already widely used in quantum optics. However, degenerate quantum gases involve massive bosonic and fermionic atoms, not massless photons. The book begins with a review of Fock states for systems of identical atoms, where large numbers of atoms occupy the various single particle states or modes. First, separate modes are considered, and here the quantum density operator is represented by a phase space distribution function of phase space variables which replace mode annihilation, creation operators, the dynamical equation for the density operator determines a Fokker-Planck equation for the distribution function, and measurable...
Hartl, M; Mikhailov, R.; Passi, I. B. S.
2008-01-01
We present two approaches, one homological and the other simplicial, for the investigation of dimension quotients of groups. The theory is illustrated, in particular, with a conceptual discussion of the fourth and fifth dimension quotients.
Fermionic impurities in Chern-Simons-matter theories
Benincasa, Paolo; Ramallo, Alfonso V.
2012-02-01
We study the addition of quantum fermionic impurities to the mathcal{N} = 6 super-symmetric Chern-Simons-matter theories in 2 + 1 spacetime dimensions. The impurities are introduced by means of Wilson loops in the antisymmetric representation of the gauge group. In a holographic setup, the system is represented by considering D6-branes probing the AdS 4 × mathbb{C}mathbb{P} 3 background of type IIA supergravity. We study the thermodynamic properties of the system and show how a Kondo lattice model with holographic dimers can be constructed. By computing the Kaluza-Klein fluctuation modes of the probe brane we determine the complete spectrum of dimensions of the impurity operators. A very rich structure is found, depending both on the Kaluza-Klein quantum numbers and on the filling fraction of the impurities.
Fermionic impurities in Chern-Simons-matter theories
Benincasa, Paolo
2011-01-01
We study the addition of quantum fermionic impurities to the N=6 supersymmetric Chern-Simons-matter theories in 2+1 spacetime dimensions. The impurities are introduced by means of Wilson loops in the antisymmetric representation of the gauge group. In a holographic setup, the system is represented by considering D6-branes probing the AdS_4 x CP^3 background of type IIA supergravity. We study the thermodynamic properties of the system and show how a Kondo lattice model with holographic dimers can be constructed. By computing the Kaluza-Klein fluctuation modes of the probe brane we determine the complete spectrum of dimensions of the impurity operators. A very rich structure is found, depending both on the Kaluza-Klein quantum numbers and on the filling fraction of the impurities.
AdS/CFT as classical to quantum correspondence in a Virtual Extra Dimension
Dolce, Donatello
2013-01-01
The correspondence between classical extra dimensional geometry and quantum behavior, typical of the AdS/CFT, has a heuristic semiclassical interpretation in terms of undulatory mechanics and relativistic geometrodynamics. We note, in fact, that the quantum recurrence of ordinary particles enters into the equations of motions in formal duality with the extra dimensional dynamics of a Kaluza-Klein theory. The kinematics of the particle in a generic interaction scheme can be described as modulations of the spacetime recurrences and encoded in corresponding geometrodynamics. The quantization can be obtained semiclassically by means of boundary conditions, so that the interference of the classical paths with different windings numbers associated to the resulting recurrences turns out to be described by the ordinary Feynman Path Integral. This description applied to the Quark-Gluon-Plasma freeze-out yields basic aspects of AdS/QCD phenomenology.
Localization and mass spectrum of q-form fields on branes
Fu, Chun-E.; Zhong, Yuan; Xie, Qun-Ying; Liu, Yu-Xiao
2016-06-01
In this paper, we investigate localization of a bulk massless q-form field on codimension-one branes by using a new Kaluza-Klein (KK) decomposition, for which there are two types of KK modes for the bulk q-form field, the q-form and (q - 1)-form modes. The first modes may be massive or massless while the second ones are all massless. These two types of KK modes satisfy two Schrödinger-like equations. For a five-dimensional brane model with a finite extra dimension, the spectrum of a bulk 3-form field on the brane consists of some massive bound 3-form KK modes as well as some massless bound 2-form ones with different configuration along the extra dimension. These 2-form modes are different from those obtained from a bulk 2-form field. For a five-dimensional degenerated Bloch brane model with an infinite extra dimension, some massive 3-form resonant KK modes and corresponding massless 2-form resonant ones are obtained for a bulk 3-form field.
Hidden symmetries of black holes in five-dimensional supergravity
Chow, David D K
2016-01-01
We consider a general charged, rotating black hole in five-dimensional STU supergravity, and show that its six-dimensional Kaluza-Klein lift admits a Killing-Yano 3-form with torsion. This underlies its known Killing tensors in five dimensions. In the generalization to gauged supergravity, we present a five-dimensional Killing-Yano 3-form with torsion when two of the gauge fields are equal, and a Killing-Stackel tensor in the general 3-charge Wu solution.
Electrodynamics and Time Orientability
Hadley, Mark J.
2017-06-01
On spacetimes that are not time orientable we construct a U(1) bundle to measure the twisting of the time axis. This single assumption, and simple construction, gives rise to Maxwell's equations of electromagnetism, the Lorentz force law and the Einstein-Maxwell equations for electromagnetism coupled to General relativity. The derivations follow the Kaluza Klein theory, but with the constraints required for connections on a U(1) bundle rather than five spacetime dimensions. The non time orientability is seen to justify and constrain Kaluza Klein theories exactly as required to unify gravitation with electromagnetism. Unlike any other schemes, apparent net electric charges arise naturally because the direction of the electric field reverses along a time reversing path. The boundary of a time reversing region can therefore have a net electric flux and appear exactly as a region containing an electric charge. The treatment is purely classical, but motivated by links between acausal structures and quantum theory.
Phenomenology of TeV little string theory from holography.
Antoniadis, Ignatios; Arvanitaki, Asimina; Dimopoulos, Savas; Giveon, Amit
2012-02-24
We study the graviton phenomenology of TeV little string theory by exploiting its holographic gravity dual five-dimensional theory. This dual corresponds to a linear dilaton background with a large bulk that constrains the standard model fields on the boundary of space. The linear dilaton geometry produces a unique Kaluza-Klein graviton spectrum that exhibits a ~TeV mass gap followed by a near continuum of narrow resonances that are separated from each other by only ~30 GeV. Resonant production of these particles at the LHC is the signature of this framework that distinguishes it from large extra dimensions, where the Kaluza-Klein states are almost a continuum with no mass gap, and warped models, where the states are separated by a TeV.
Degenerate Density Perturbation Theory
Palenik, Mark C
2016-01-01
Fractional occupation numbers can be used in density functional theory to create a symmetric Kohn-Sham potential, resulting in orbitals with degenerate eigenvalues. We develop the corresponding perturbation theory and apply it to a system of $N_d$ degenerate electrons in a harmonic oscillator potential. The order-by-order expansions of both the fractional occupation numbers and unitary transformations within the degenerate subspace are determined by the requirement that a differentiable map exists connecting the initial and perturbed states. Using the X$\\alpha$ exchange-correlation (XC) functional, we find an analytic solution for the first-order density and first through third-order energies as a function of $\\alpha$, with and without a self-interaction correction. The fact that the XC Hessian is not positive definite plays an important role in the behavior of the occupation numbers.
Degenerate density perturbation theory
Palenik, Mark C.; Dunlap, Brett I.
2016-09-01
Fractional occupation numbers can be used in density functional theory to create a symmetric Kohn-Sham potential, resulting in orbitals with degenerate eigenvalues. We develop the corresponding perturbation theory and apply it to a system of Nd degenerate electrons in a harmonic oscillator potential. The order-by-order expansions of both the fractional occupation numbers and unitary transformations within the degenerate subspace are determined by the requirement that a differentiable map exists connecting the initial and perturbed states. Using the X α exchange-correlation (XC) functional, we find an analytic solution for the first-order density and first- through third-order energies as a function of α , with and without a self-interaction correction. The fact that the XC Hessian is not positive definite plays an important role in the behavior of the occupation numbers.
Vortices as degenerate metrics
Baptista, J M
2012-01-01
We note that the Bogomolny equation for abelian vortices is precisely the condition for invariance of the Hermitian-Einstein equation under a degenerate conformal transformation. This leads to a natural interpretation of vortices as degenerate hermitian metrics that satisfy a certain curvature equation. Using this viewpoint, we rephrase standard results about vortices and make some new observations. We note the existence of a conceptually simple, non-linear rule for superposing vortex solutions, and we describe the natural behaviour of the L^2-metric on the moduli space upon certain restrictions.
Small automorphic representations and degenerate Whittaker vectors
Gustafsson, Henrik P A; Persson, Daniel
2014-01-01
We investigate Fourier coefficients of automorphic forms on split simply-laced Lie groups G. We show that for automorphic representations of small Gelfand-Kirillov dimension the Fourier coefficients are completely determined by certain degenerate Whittaker vectors on G. Although we expect our results to hold for arbitrary simply-laced groups, we give complete proofs only for G=SL(3) and G=SL(4). This is based on a method of Ginzburg that associates Fourier coefficients of automorphic forms with nilpotent orbits of G. Our results complement and extend recent results of Miller and Sahi. We also use our formalism to calculate various local (real and p-adic) spherical vectors of minimal representations of the exceptional groups E_6, E_7, E_8 using global (adelic) degenerate Whittaker vectors, correctly reproducing existing results for such spherical vectors obtained by very different methods.
Kraepelin and degeneration theory.
Hoff, Paul
2008-06-01
Emil Kraepelin's contribution to the clinical and scientific field of psychiatry is recognized world-wide. In recent years, however, there have been a number of critical remarks on his acceptance of degeneration theory in particular and on his political opinion in general, which was said to have carried "overtones of proto-fascism" by Michael Shepherd [28]. The present paper discusses the theoretical cornerstones of Kraepelinian psychiatry with regard to their relevance for Kraepelin's attitude towards degeneration theory. This theory had gained wide influence not only in scientific, but also in philosophical and political circles in the last decades of the nineteenth century. There is no doubt that Kraepelin, on the one hand, accepted and implemented degeneration theory into the debate on etiology and pathogenesis of mental disorders. On the other hand, it is not appropriate to draw a simple and direct line from early versions of degeneration theory to the crimes of psychiatrists and politicians during the rule of national socialism. What we need, is a differentiated view, since this will be the only scientific one. Much research needs to be done here in the future, and such research will surely have a significant impact not only on the historical field, but also on the continuous debate about psychiatry, neuroscience and neurophilosophy.
X-82 to Treat Age-related Macular Degeneration
2017-01-12
Age-Related Macular Degeneration (AMD); Macular Degeneration; Exudative Age-related Macular Degeneration; AMD; Macular Degeneration, Age-related, 10; Eye Diseases; Retinal Degeneration; Retinal Diseases
The precision electroweak data in warped extra-dimension models
Bouchart, Charles
2008-01-01
The Randall-Sundrum scenario with Standard Model fields in the bulk and a custodial symmetry is considered. We determine the several minimal quark representations allowing to address the anomalies in the forward-backward b-quark asymmetry A^b_FB, while reproducing the bottom and top masses via wave function overlaps. The calculated corrections of the Zbb coupling include the combined effects of mixings with both Kaluza-Klein excitations of gauge bosons and new b'-like states. It is shown that the mechanism, in which the left-handed doublet of third generation quarks results from a mixing on the UV boundary of introduced fields Q_1L and Q_2L, is necessary for phenomenological reasons. Within the obtained models, both the global fit of R_b with A^b_FB [at the various center of mass energies] and the fit of last precision electroweak data in the light fermion sector can simultaneously be improved significantly with respect to the pure Standard Model case, for M_KK = 3,4,5 TeV (first KK gauge boson) and m_h > 115...
Uber-naturalness: unexpectedly light scalars from supersymmetric extra dimensions
Burgess, C P; Quevedo, F
2010-01-01
Standard lore asserts that quantum effects generically forbid the occurrence of light (non-pseudo-Goldstone) scalars having masses smaller than the Kaluza Klein scale, M_KK, in extra-dimensional models, or the gravitino mass, M_3/2, in supersymmetric situations. We argue that a hidden assumption underlies this lore: that the scale of gravitational physics, M_g, (e.g. the string scale, M_s, in string theory) is of order the Planck mass, M_p = 10^18 GeV. We explore sensitivity to this assumption using the spectrum of masses arising within the specific framework of large-volume string compactifications, for which the ultraviolet completion at the gravity scale is explicitly known to be a Type IIB string theory. In such models the separation between M_g and M_p is parameterized by the (large) size of the extra dimensional volume, V (in string units), according to M_p: M_g: M_KK: M_3/2 = 1: V^{-1/2}: V^{-2/3}: V^{-1}. We find that the generic size of quantum corrections to masses is of the order of M_KK M_3/2 / M_...
On Degenerate Partial Differential Equations
Chen, Gui-Qiang G.
2010-01-01
Some of recent developments, including recent results, ideas, techniques, and approaches, in the study of degenerate partial differential equations are surveyed and analyzed. Several examples of nonlinear degenerate, even mixed, partial differential equations, are presented, which arise naturally in some longstanding, fundamental problems in fluid mechanics and differential geometry. The solution to these fundamental problems greatly requires a deep understanding of nonlinear degenerate parti...
Christensen, Lars Winther
2000-01-01
This book is intended as a reference for mathematicians working with homological dimensions in commutative algebra and as an introduction to Gorenstein dimensions for graduate students with an interest in the same. Any admirer of classics like the Auslander-Buchsbaum-Serre characterization of regular rings, and the Bass and Auslander-Buchsbaum formulas for injective and projective dimension of f.g. modules will be intrigued by this book's content. Readers should be well-versed in commutative algebra and standard applications of homological methods. The framework is that of complexes, but all major results are restated for modules in traditional notation, and an appendix makes the proofs accessible for even the casual user of hyperhomological methods.
Oscillatory integrals for phase functions having certain degenerate critical points
Institute of Scientific and Technical Information of China (English)
Jinmyong KIM; ZHENG Quan
2008-01-01
The paper is concerned with oscillatory integrals for phase functions having certain de-generate critical points. Under a finite type condition of phase functions we show the estimate of oscillatory integrals of the first kind. The decay of the oscillatory integral depends on indices of the finite type, the spatial dimension and the symbol.
Laenderyggens degeneration og radiologi
DEFF Research Database (Denmark)
Jacobsen, Steffen; Gosvig, Kasper Kjaerulf; Sonne-Holm, Stig
2006-01-01
Low back pain (LBP) is one of the most common conditions, and at the same time one of the most complex nosological entities. The lifetime prevalence is approximately 80%, and radiological features of lumbar degeneration are almost universal in adults. The individual risk factors for LBP and signi......Low back pain (LBP) is one of the most common conditions, and at the same time one of the most complex nosological entities. The lifetime prevalence is approximately 80%, and radiological features of lumbar degeneration are almost universal in adults. The individual risk factors for LBP...... and significant relationships between radiological findings and subjective symptoms have both been notoriously difficult to identify. The lack of consensus on clinical criteria and radiological definitions has hampered the undertaking of properly executed epidemiological studies. The natural history of LBP...
Cataracts and macular degeneration.
Shoch, D
1979-09-01
The intraocular lens restores general vision and some degree of independence and mobility to patients with dense cataracts and macular degeneration. The patient, however, must be repeatedly warned that fine central vision, particularly reading, will not be possible after the surgery. An aphakic spectacle leaves such patients a narrow band of vision when superimposed over the macular lesion, and contact lenses are too small for the patient to manage insertion without help.
Scaling dimensions in hidden Kerr/CFT
Lowe, David A; Skanata, Antun
2011-01-01
It has been proposed that a hidden conformal field theory (CFT) governs the dynamics of low frequency scattering in a general Kerr black hole background. We further investigate this correspondence by mapping higher order corrections to the massless wave equations in a Kerr background to an expansion within the CFT in terms of higher dimension operators. This implies the presence of infinite towers of CFT primary operators with positive conformal dimensions compatible with unitarity. The exact Kerr background softly breaks the conformal symmetry and the scaling dimensions of these operators run with frequency. The scale-invariant fixed point is dual to a degenerate case of flat spacetime.
Geometric phases for non-degenerate and degenerate mixed states
Singh, K; Basu, K; Chen, J L; Du Jiang Feng
2003-01-01
This paper focuses on the geometric phase of general mixed states under unitary evolution. Here we analyze both non-degenerate as well as degenerate states. Starting with the non-degenerate case, we show that the usual procedure of subtracting the dynamical phase from the total phase to yield the geometric phase for pure states, does not hold for mixed states. To this end, we furnish an expression for the geometric phase that is gauge invariant. The parallelity conditions are shown to be easily derivable from this expression. We also extend our formalism to states that exhibit degeneracies. Here with the holonomy taking on a non-abelian character, we provide an expression for the geometric phase that is manifestly gauge invariant. As in the case of the non-degenerate case, the form also displays the parallelity conditions clearly. Finally, we furnish explicit examples of the geometric phases for both the non-degenerate as well as degenerate mixed states.
Degenerate elliptic resonances
Gentile, G
2004-01-01
Quasi-periodic motions on invariant tori of an integrable system of dimension smaller than half the phase space dimension may continue to exists after small perturbations. The parametric equations of the invariant tori can often be computed as formal power series in the perturbation parameter and can be given a meaning via resummations. Here we prove that, for a class of elliptic tori, a resummation algorithm can be devised and proved to be convergent, thus extending to such lower-dimensional invariant tori the methods employed to prove convergence of the Lindstedt series either for the maximal (i.e. KAM) tori or for the hyperbolic lower-dimensional invariant tori
Intervertebral disc degeneration in dogs
Bergknut, Niklas
2011-01-01
Back pain is common in both dogs and humans, and is often associated with intervertebral disc (IVD) degeneration. The IVDs are essential structures of the spine and degeneration can ultimately result in diseases such as IVD herniation or spinal instability. In order to design new treatments halting
Institute of Scientific and Technical Information of China (English)
LUO Xin-Lian; BAI Hua; ZHAO Lei
2008-01-01
Regardless of the formation mechanism, an exotic object, the double degenerate star (DDS), is introduced and investigated, which is composed of baryonic matter and some unknown fermion dark matter. Different from the simple white dwarfs (WDs), there is additional gravitational force provided by the unknown fermion component inside DDSs, which may strongly affect the structure and the stability of such kind of objects. Many possible and strange observational phenomena connecting with them are concisely discussed. Similar to the normal WD, this object can also experience thermonuclear explosion as type Ia supernova explosion when DDS's mass exceeds the maximum mass that can be supported by electron degeneracy pressure. However, since the total mass of baryonic matter can be much lower than that of WD at Chandrasekhar mass limit, the peak luminosity should be much dimmer than what we expect before, which may throw a slight shadow on the standard candle of SN Ia in the research of cosmology.
Facts about Age-Related Macular Degeneration
... Degeneration (AMD) > Facts About Age-Related Macular Degeneration Facts About Age-Related Macular Degeneration This information was ... an Eye Care Professional Last Reviewed: September 2015 Fact Sheet Blurb The National Eye Institute (NEI) is ...
2013-01-01
A few weeks ago, I had a vague notion of what TED was, and how it worked, but now I’m a confirmed fan. It was my privilege to host CERN’s first TEDx event last Friday, and I can honestly say that I can’t remember a time when I was exposed to so much brilliance in such a short time. TEDxCERN was designed to give a platform to science. That’s why we called it Multiplying Dimensions – a nod towards the work we do here, while pointing to the broader importance of science in society. We had talks ranging from the most subtle pondering on the nature of consciousness to an eighteen year old researcher urging us to be patient, and to learn from our mistakes. We had musical interludes that included encounters between the choirs of local schools and will.i.am, between an Israeli pianist and an Iranian percussionist, and between Grand Opera and high humour. And although I opened the event by announcing it as a day off from physics, we had a quite brill...
Institute of Scientific and Technical Information of China (English)
Piotr Dowbor; Adam Hajduk
2007-01-01
Three different notions of geometric degeneration for finite dimensional alge-bras are compared.It is proved that for algebras A0 and A1 of same dimension,if A0 is a CB-degeneration of A1,then A0 is a degeneration of A1 in the classical sense; moreover,if additionally A0 and A1 are basic,then Ao is a CB-degeneration of A1 if and only if A0is a rigid degeneration of A1.It is also shown that CB-degenerations along affine lines in the different dimension case do not differ so much from those in the equal dimension case.
[Age related macular degeneration].
Sayen, Alexandra; Hubert, Isabelle; Berrod, Jean-Paul
2011-02-01
Age-related macular degeneration (ARMD) is a multifactorial disease caused by a combination of genetic and environmental factors. It is the first cause of blindness in patients over 50 in the western world. The disease has been traditionally classified into early and late stages with dry (atrophic) and wet (neovascular) forms: neovascular form is characterized by new blood vessels development under the macula (choroidal neovascularisation) which lead to a rapid decline of vision associated with metamorphopsia and requiring an urgent ophtalmological examination. Optical coherence tomography is now one of the most important part of the examination for diagnosis and treatment. Patient with age related maculopathy should consider taking a dietary supplement such that used in AREDS. The treatment of the wet ARMD has largely beneficied since year 2006 of anti-VEGF (vascular endothelial growth factor) molecules such as ranibizumab or bevacizumab given as repeated intravitreal injections. A systematic follow up each 4 to 8 week in required for several years. There is no effective treatment at the moment for dry AMD. For patients with binocular visual acuity under 60/200 rehabilitation includes low vision specialist, vision aids and psychological support.
Integrable systems, toric degenerations and Okounkov bodies
Harada, Megumi
2012-01-01
Let X be a smooth projective variety of dimension n over C equipped with a very ample line bundle L. Using the theory of Okounkov bodies and an associated toric degeneration, we construct -- under a mild technical hypothesis on X -- an integrable system on X in the sense of symplectic geometry. More precisely, we construct a collection of real-valued functions {H_1, ..., H_n} on X which are continuous on all of X, smooth on an open dense subset U of X, and pairwise Poisson-commute on U. Here the symplectic structure on X is the pullback of the Fubini-Study form on P(H^0(X, L)^*) via the Kodaira embedding. The image of the `moment map' (H_1, ..., H_n): X to R^n is precisely the Okounkov body \\Delta = \\Delta(R, v) associated to the homogeneous coordinate ring R of X, and an appropriate choice of valuation v on R. Our main technical tools come from algebraic geometry, differential (Kaehler) geometry, and analysis. Specifically, we use: a toric degeneration of X to a (not necessarily normal) toric variety X_0, th...
On the degenerated Arnold-Givental conjecture
Lu, Guangcun
2008-01-01
Let $(M, \\omega, \\tau)$ be a real symplectic manifold with nonempty and compact real part $L={\\rm Fix}(\\tau)$. We study the following degenerated version of the Arnold-Givental conjecture: $\\sharp(L\\cap\\phi(L))\\ge{\\rm Cuplength}_{\\F}(L)$ for any Hamiltonian diffeomorphism $\\phi:M\\to M$ and $\\F=\\Z, \\Z_2$. Suppose that $(M, \\omega)$ is geometrical bounded for some $J\\in{\\cal J}(M, \\omega)$ with $\\tau^\\ast J=-J$. We prove $\\sharp(L\\cap\\phi(L))\\ge {\\rm Cuplength}_{\\F}(L)$ for $\\F=\\Z_2$, and $\\F=\\Z_2, \\Z$ if $L$ is orientable, and for every Hamiltonian diffeomorphism $\\phi$ generated by a compactly supported Hamiltonian function whose Hofer norm is less than the minimal area of all nonconstant $J$-holomorphic spheres in $M$. In particular, this implies that the above degenerated Arnold-Givental conjecture holds on the K3-surfaces and closed negative monotone real symplectic manifolds of dimension $2n$ with either $n\\le 3$ or minimal Chern number $N\\ge n-2$. As consequences we get that every Hamiltonian diffeomorph...
Institute of Scientific and Technical Information of China (English)
吴迪; 吴双清; 杨树政
2015-01-01
将转动带电的Rasheed-Larsen双荷黑洞解推广到ω-变形的Kaluza-Klein超引力理论中,得到了新的ω-变形的转动双荷黑洞精确解,并对其热力学性质进行了仔细地分析,发现除了在电磁规范势1-形式、电荷、磁荷、静电势和静磁势中需要同时作一个电磁对偶转动以外,ω-变形参数对黑洞度规、质量、角动量、热力学第一定律和Smarr公式没有影响.
Degenerate pseudo-Riemannian metrics
Hervik, Sigbjorn; Yamamoto, Kei
2014-01-01
In this paper we study pseudo-Riemannian spaces with a degenerate curvature structure i.e. there exists a continuous family of metrics having identical polynomial curvature invariants. We approach this problem by utilising an idea coming from invariant theory. This involves the existence of a boost, the existence of this boost is assumed to extend to a neighbourhood. This approach proves to be very fruitful: It produces a class of metrics containing all known examples of degenerate metrics. To date, only Kundt and Walker metrics have been given, however, our study gives a plethora of examples showing that degenerate metrics extend beyond the Kundt and Walker examples. The approach also gives a useful criterion for a metric to be degenerate. Specifically, we use this to study the subclass of VSI and CSI metrics (i.e., spaces where polynomial curvature invariants are all vanishing or constants, respectively).
Age-Related Macular Degeneration
... version of this page please turn Javascript on. Age-related Macular Degeneration About AMD Click for more ... a leading cause of vision loss among people age 60 and older. It causes damage to the ...
Warped extra dimensions. Flavor, precision tests and Higgs physics
Energy Technology Data Exchange (ETDEWEB)
Goertz, Florian
2011-07-01
In this thesis, the phenomenology of the Randall-Sundrum setup is investigated. In this context models with and without an enlarged SU(2){sub L} x SU(2){sub R} x U(1){sub X} x P{sub LR} gauge symmetry, which removes corrections to the T parameter and to the Zb{sub L}b{sub L} coupling, are compared with each other. The Kaluza-Klein decomposition is formulated within the mass basis, which allows for a clear understanding of various model-specific features. A complete discussion of tree-level flavor-changing effects is presented. Exact expressions for five dimensional propagators are derived, including Yukawa interactions that mediate flavor-off-diagonal transitions. The symmetry that reduces the corrections to the left-handed Zbb coupling is analyzed in detail. In the literature, Randall-Sundrum models have been used to address the measured anomaly in the tt forward-backward asymmetry. However, it is shown that this is not possible within a natural approach to flavor. The rare decays t{yields}cZ and t{yields}ch are investigated, where in particular the latter could be observed at the LHC. A calculation of {gamma}{sup B}{sub s12} in the presence of new physics is presented. It is shown that the Randall-Sundrum setup allows for an improved agreement with measurements of A{sup s}{sub SL}, S{sub {psi}}{sub {phi}}, and {delta}{gamma}{sub s}. For the first time, a complete one-loop calculation of all relevant Higgs-boson production and decay channels in the custodial Randall-Sundrum setup is performed, revealing a sensitivity to large new-physics scales at the LHC.
On the degenerate phase boundaries
Ma, Y; Kuang, Z; Ma, Yongge; Liang, Canbin; Kuang, Zhiquan
1999-01-01
The structure of the phase boundary between degenerate and non-degenerate regions in Ashtekar's gravity has been studied by Bengtsson and Jacobson who conjectured that the "phase boundary" should always be null. In this paper, we reformulate the reparametrization procedure in the mapping language and distinguish a phase boundary from its image. It is shown that the image has to be null, while the nullness of the phase boundary requries more suitable criterion.
Wilson's disease (hepatolenticular degeneration).
Herron, B E
1976-01-01
Wilson's disease, or hepatolenticular degeneration, is a rare inherited disorder of copper metabolism which usually affects young people. Excess copper accumulates in the tissues, primarily in the liver, brain, and cornea. This copper deposition results in a wide range of hepatic and neurological symptoms, and may produce psychiatric illness. Hepatic involvement often occurs in childhood, while neurological deficits generally are detected at a later age. The disease is inherited in an autosomal recessive fashion. Ocular findings are of particular importance because the corneal copper deposition, forming the Kayser-Fleischer ring,is the only pathognomonic sign of the disease. The structure of the ring and the presence of copper have been well established. An anterior capsular deposition of copper in the lens results in a characteristic sunflower cataract in some of these patients. Other ocular abnormalities have been described but are much less common. The pathogenesis of the disease and the basic genetic defect remain obscure. It is clear that there is excess copper in the tissues, but the mechanism of its deposition is unknown. It is in some way associated with a failure to synthesize the serum copper protein ceruloplasmin normally. Another theory suggests that an abnormal protein with a high affinity for copper may bind the metal in the tissues. The diagnosis may be suggested by the clinical manifestations and confirmed by the presence of a Kayser-Fleischer ring. In the absence of these findings biochemical determinations are necessary. The most important of these are the serum ceruloplasmin, the urinary copper, and the hepatic copper concentration on biopsy. Treatment consists in the administration of the copper chelating agent, penicillamine, and the avoidance of a high copper intake. This usually results in marked clinical improvement if irreversible tissue damage has not occurred. Maintenance therapy for life is necessary in order to continue the negative
Kinematic Quantities and Raychaudhuri Equations in a $5D$ Universe
Bejancu, Aurel
2015-01-01
Based on some ideas emerged from the classical Kaluza-Klein theory, we present a $5D$ universe as a product bundle over the $4D$ spacetime. This enables us to introduce and study two categories of kinematic quantities (expansions, shear, vorticity) in a $5D$ universe. One category is related to the fourth dimension (time), and the other one comes from the assumption of the existence of the fifth dimension. The Raychaudhuri type equations that we obtain in the paper, lead us to results on the evolution of both the $4D$ expansion and $5D$ expansion in a $5D$ universe.
Phenomenology of Noncommutative Field Theories
Carone, C D
2006-01-01
Experimental limits on the violation of four-dimensional Lorentz invariance imply that noncommutativity among ordinary spacetime dimensions must be small. In this talk, I review the most stringent bounds on noncommutative field theories and suggest a possible means of evading them: noncommutativity may be restricted to extra, compactified spatial dimensions. Such theories have a number of interesting features, including Abelian gauge fields whose Kaluza-Klein excitations have self couplings. We consider six-dimensional QED in a noncommutative bulk, and discuss the collider signatures of the model.
Kinematic quantities and Raychaudhuri equations in a 5D universe
Energy Technology Data Exchange (ETDEWEB)
Bejancu, Aurel [Kuwait University, Department of Mathematics, Safat (Kuwait)
2015-07-15
Based on some ideas that have emerged from the classical Kaluza-Klein theory, we present a 5D universe as a product bundle over the 4D spacetime. This enables us to introduce and study two categories of kinematic quantities (expansions, shear, vorticity) in a 5D universe. One category is related to the fourth dimension (time), and the other one comes from the assumption of the existence of the fifth dimension. The Raychaudhuri type equations that we obtain in the paper, lead us to results on the evolution of both the 4D expansion and the 5D expansion in a 5D universe. (orig.)
Higgs Dark Matter from a Warped Extra-Dimension -- the truncated-inert-doublet model
Ahmed, Aqeel; Gunion, John F; Jiang, Yun
2015-01-01
We construct a 5D $\\mathbb{Z}_2$-symmetric model with three D3-branes: two IR ones with negative tension located at ends of an extra-dimensional interval and one UV-brane with positive tension placed in the middle of the interval. Within this setup we investigate the low-energy effective theory for the bulk SM bosonic sector. The $\\mathbb{Z}_2$-even zero-modes correspond to known standard degrees of freedom, whereas the $\\mathbb{Z}_2$-odd zero modes might serve as dark sector. We discuss two scenarios for spontaneous breaking of the gauge symmetry, one based on expansion of the bulk Higgs field around extra-dimensional vev with non-trivial profile and the second in which the symmetry breaking is triggered by a vev of Kaluza-Klein modes of the bulk Higgs field. It is shown that they lead to the same low-energy effective theory. The effective low-energy scalar sector contains a scalar which mimics the Standard Model (SM) Higgs boson and a second stable scalar particle (dark-Higgs) that is a dark matter candidat...
Delta F=2 Observables and Fine-Tuning in a Warped Extra Dimension with Custodial Protection
Blanke, Monika; Duling, Bjoern; Gori, Stefania; Weiler, Andreas
2009-01-01
We present a complete study of Delta S = 2 and Delta B = 2 processes in warped extra dimensional models with a custodial protection of Z b_L anti-b_L, including epsilon_K, Delta M_K, Delta M_s, Delta M_d, A_SL^q, Delta Gamma_q, A_CP(B_d -> psi K_S) and A_CP(B_s -> psi phi). These processes are affected by tree level contributions from Kaluza-Klein gluons and new heavy electroweak gauge bosons Z_H and Z', with the latter implied by the custodial protection mechanism. We confirm recent findings that the fully anarchic approach where all the hierarchies in quark masses and weak mixing angles are geometrically explained seems implausible and we confirm that the KK mass scale M_KK generically has to be at least ~ 20TeV to satisfy the epsilon_K constraint. We point out, however, that there exist regions in parameter space with only modest fine-tuning in the 5D Yukawa couplings which satisfy all existing Delta F = 2 and electroweak precision constraints for scales M_KK ~ 3TeV in reach of the LHC. Simultaneously we f...
Warping, Extra Dimensions and a Slice of AdS_d
McDonald, Kristian L
2009-01-01
Inspired by the Randall-Sundrum (RS) framework we consider a number of phenomenologically relevant model building questions on a slice of compactified AdS_d for d >5. Such spaces are interesting as they enable one to realize the weak scale via warping. We perform the Kaluza-Klein (KK) reduction for gravitons and bulk vectors in these spaces and for the case of AdS_6 consider the KK spectrum of gauge-scalars. We further obtain the KK towers for bulk fermions on a slice of AdS_7 and AdS_9 and show that the RS approach to flavor generalizes to these spaces with the localization of chiral zero mode fermions controlled by their bulk Dirac mass parameters. However for the phenomenologically interesting case where the transverse radius is R^{-1}\\sim TeV we show that bulk Standard Model fields are not viable due to a resulting volume suppression of the gauge coupling constants. A similar suppression occurs for the case of UV localization. Thus it seems that the Standard Model fields should be confined to the infrared...
On the computational complexity of degenerate unit distance representations of graphs
Kratochvil, Jan; Pisanski, Tomaz
2010-01-01
Some graphs admit drawings in the Euclidean k-space in such a (natu- ral) way, that edges are represented as line segments of unit length. Such drawings will be called k dimensional unit distance representations. When two non-adjacent vertices are drawn in the same point, we say that the representation is degenerate. The dimension (the Euclidean dimension) of a graph is defined to be the minimum integer k needed that a given graph has non-degenerate k dimensional unit distance representation (with the property that non-adjacent vertices are mapped to points, that are not distance one appart). It is proved that deciding if an input graph is homomorphic to a graph with dimension k >= 2 (with the Euclidean dimension k >= 2) are NP-hard problems.
Genetics Home Reference: age-related macular degeneration
... Resources (3 links) BrightFocus Foundation: Macular Degeneration Treatment Macular Degeneration Partnership: Low Vision Rehabilitation Prevent Blindness America: Age-Related Macular Degeneration (AMD) ...
Gribov ambiguity and degenerate systems
Canfora, Fabrizio; Salgado-Rebolledo, Patricio; Zanelli, Jorge
2014-01-01
The relation between Gribov ambiguity and degeneracies in the symplectic structure of physical systems is analyzed. It is shown that, in finite-dimensional systems, the presence of Gribov ambiguities in regular constrained systems (those where the constraints are functionally independent) always leads to a degenerate symplectic structure upon Dirac reduction. The implications for the Gribov-Zwanziger approach to QCD are discussed.
Energy Technology Data Exchange (ETDEWEB)
Terning, J. (John)
2002-01-01
The author reviews the calculation of the glueball spectrum in non-supersymmetric Yang-Mills theory (in 3 and 4 dimensions) using the conjectured duality between supergravity and large N gauge theories. The glueball masses are obtained by solving the supergravity wave equations in a black hole geometry. The masses obtained this way are in unexpectedly good agreement with the available lattice data, and are much better than strong-coupling expansion results. The author also shows how to use a modified version of the duality to calculate the glueball mass spectrum with some of the Kaluza-Klein states of the supergravity theory decoupled from the spectrum.
Einstein Gravity-Supergravity Correspondence
Chen, C M; Sharakin, S A; Chen, Chiang-Mei; Gal'tsov, Dmitri V.; Sharakin, Sergei A.
1999-01-01
A correspondence between the three-block truncated 11D supergravity and the 8D pure Einstein gravity with two commuting Killing symmetries is discussed. The Kaluza-Klein two-forms of the 6D theory obtained after dimensional reduction along the Killing orbits generate the four-form field of supergravity via an inverse dualization. Thus any solution to the vacuum Einstein equations in eight dimensions depending on six coordinates have 11D-supergravity counterparts with the non-trivial four-form field. Using this proposed duality we derive a new dyon solution of 11D supergravity describing the M2 and M5-branes intersecting at a point.
The near-horizon geometry of dilaton-axion black holes
Clément, G
2001-01-01
Static black holes of dilaton-axion gravity become singular in the extreme limit, which prevents a direct determination of their near-horizon geometry. This is addressed by first taking the near-horizon limit of extreme rotating NUT-less black holes, and then going to the static limit. The resulting four-dimensional geometry may be lifted to a Bertotti-Robinson-like solution of six-dimensional vacuum gravity, which also gives the near-horizon geometry of extreme Kaluza-Klein black holes in five dimensions.
The Einstein field equation in a multidimensional universe.
Pekonen, Osmo
1988-07-01
String theory [4] predicts that the universe has 10 or 26 dimensions. A salient problem is how the Einstein field equation should be written in terms of these revivified Kaluza-Klein cosmologies. The answer is by now well-known, yet nobody seems to have rewritten the seminal computation in [6] where an unnecessarily involved Euler-Lagrange variational method is employed and, curiously enough, no allusion to the Gauss-Bonnet-Chern theorem is made. We provide a more straightforward argument, which has been inspired by Hilbert's original derivation of the Einstein field equation [5].
Supersymmetric 4D rotating black holes from 5D black rings
Energy Technology Data Exchange (ETDEWEB)
Elvang, Henriette [Department of Physics, University of California, Santa Barbara, CA 93106-9530 (United States); Emparan, Roberto [Institucio Catalana de Recerca i Estudis Avancats (ICREA) (Mexico); Departament de Fisica Fonamental, and C.E.R. en Astrofisica, Fisica de PartIcules i Cosmologia, Universitat de Barcelona, Diagonal 647, E-08028 Barcelona (Spain); Mateos, David [Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2L 2Y5 (Canada); Reall, Harvey S. [Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA 93106-4030 (United States)
2005-08-01
We present supersymmetric solutions describing black holes with non-vanishing angular momentum in four dimensional asymptotically flat space. The solutions are obtained by Kaluza-Klein reduction of five-dimensional supersymmetric black rings wrapped on the fiber of a Taub-NUT space. We show that in the four-dimensional description the singularity of the nut can be hidden behind a regular black hole event horizon and thereby obtain an explicit example of a non-static multi-black hole solution in four asymptotically flat dimensions.
Five-Dimensional Cosmological Model with Variable G and Λ
Institute of Scientific and Technical Information of China (English)
H. Baysal; (I). Yilmaz
2007-01-01
@@ Einstein's field equations with G and Λ both varying with time are considered in the presence of a perfect fluid for five-dimensional cosmological model in a way which conserves the energy momentum tensor of the matter content. Several sets of explicit solutions in the five-dimensional Kaluza-Klein type cosmological models with variable G and Λ are obtained. The diminishment of extra dimension with the evolution of the universe for the five-dimensional model is exhibited. The physical properties of the models are examined.
Abelian tensor hierarchy in 4D, N = 1 superspace
Becker, Katrin; Becker, Melanie; Linch, William D.; Robbins, Daniel
2016-03-01
With the goal of constructing the supersymmetric action for all fields, massless and massive, obtained by Kaluza-Klein compactification from type II theory or M-theory in a closed form, we embed the (Abelian) tensor hierarchy of p-forms in four-dimensional, N =1superspaceandconstructitsChern-Simons-likeinvariants. Whenspecializedtothe case in which the tensors arise from a higher-dimensional theory, the invariants may be interpreted as higher-dimensional Chern-Simons forms reduced to four dimensions. As an application of the formalism, we construct the eleven-dimensional Chern-Simons form in terms of four-dimensional, N = 1 superfields.
Abazov, V; Abolins, M; Acharya, B S; Adams, M; Adams, T; Aguiló, E; Ahn, S H; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Anastasoaie, M; Ancu, L S; Andeen, T; Anderson, S; Andrieu, B; Anzelc, M S; Arnoud, Y; Arov, M; Arthaud, M; Askew, A; Åsman, B; Assis-Jesus, A C S; Atramentov, O; Autermann, C; Avila, C; Ay, C; Badaud, F; Baden, A; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, S; Banerjee, P; Barberis, E; Barfuss, A F; Bargassa, P; Baringer, P; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Beale, S; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Bellavance, A; Benítez, J A; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Biscarat, C; Blazey, G; Blekman, F; Blessing, S; Bloch, D; Bloom, K; Böhnlein, A; Boline, D; Bolton, T A; Borissov, G; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Brown, D; Buchanan, N J; Buchholz, D; Bühler, M; Büscher, V; Bunichev, S; Burdin, S; Burke, S; Burnett, T H; Buszello, C P; Butler, J M; Calfayan, P; Calvet, S; Cammin, J; Carvalho, W; Casey, B C K; Cason, N M; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chan, K; Chandra, A; Charles, F; Cheu, E; Chevallier, F; Cho, D K; Choi, S; Choudhary, B; Christofek, L; Christoudias, T; Cihangir, S; Claes, D; Coadou, Y; Cooke, M; Cooper, W E; Corcoran, M; Couderc, F; Cousinou, M C; Crepe-Renaudin, S; Cutts, D; Cwiok, M; Da Motta, H; Das, A; Davies, G; De, K; De Jong, S J; De La Cruz-Burelo, E; De Oliveira Martins, C; Degenhardt, J D; Déliot, F; Demarteau, M; Demina, R; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Dominguez, A; Dong, H; Dudko, L V; Duflot, L; Dugad, S R; Duggan, D; Duperrin, A; Dyer, J; Dyshkant, A; Eads, M; Edmunds, D; Ellison, J; Elvira, V D; Enari, Y; Eno, S; Ermolov, P; Evans, H; Evdokimov, A; Evdokimov, V N; Ferapontov, A V; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Ford, M; Fortner, M; Fox, H; Fu, S; Fuess, S; Gadfort, T; Galea, C F; Gallas, E; Galyaev, E; García, C; García-Bellido, A; Gavrilov, V; Gay, P; Geist, W; Gelé, D; Gerber, C E; Gershtein, Yu; Gillberg, D; Ginther, G; Gollub, N; Gómez, B; Goussiou, A; Grannis, P D; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, P; Grivaz, J F; Grohsjean, A; Grünendahl, S; Grünewald, M W; Guo, J; Guo, F; Gutíerrez, P; Gutíerrez, G; Haas, A; Hadley, N J; Haefner, P; Hagopian, S; Haley, J; Hall, I; Hall, R E; Han, L; Hanagaki, K; Hansson, P; Harder, K; Harel, A; Harrington, R; Hauptman, J M; Hauser, R; Hays, J; Hebbeker, T; Hedin, D; Hegeman, J G; Heinmiller, J M; Heinson, A P; Heintz, U; Hensel, C; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hobbs, J D; Hoeneisen, B; Hoeth, H; Hohlfeld, M; Hong, S J; Hossain, S; Houben, P; Hu, Y; Hubacek, Z; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jakobs, K; Jarvis, C; Jesik, R; Johns, K; Johnson, C; Johnson, M; Jonckheere, A; Jonsson, P; Juste, A; Käfer, D; Kajfasz, E; Kalinin, A M; Kalk, J R; Kalk, J M; Kappler, S; Karmanov, D; Kasper, P; Katsanos, I; Kau, D; Kaur, R; Kaushik, V; Kehoe, R; Kermiche, S; Khalatyan, N; Khanov, A; Kharchilava, A; Kharzheev, Yu M; Khatidze, D; Kim, H; Kim, T J; Kirby, M H; Kirsch, M; Klima, B; Kohli, J M; Konrath, J P; Kopal, M; Korablev, V M; Kozelov, A V; Krop, D; Kühl, T; Kumar, A; Kunori, S; Kupco, A; Kurca, T; Kvita, J; Lacroix, F; Lam, D; Lammers, S; Landsberg, G; Lebrun, P; Lee, W M; Leflat, A; Lehner, F; Lellouch, J; Lévêque, J; Lewis, P; Li, J; Li, Q Z; Li, L; Lietti, S M; Lima, J G R; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Y; Liu, Z; Lobo, L; Lobodenko, A; Lokajícek, M; Love, P; Lubatti, H J; Lyon, A L; Maciel, A K A; Mackin, D; Madaras, R J; Mättig, P; Magass, C; Magerkurth, A; Mal, P K; Malbouisson, H B; Malik, S; Malyshev, V L; Mao, H S; Maravin, Y; Martin, B; McCarthy, R; Melnitchouk, A; Mendes, A; Mendoza, L; Mercadante, P G; Merkin, M; Merritt, K W; Meyer, J; Meyer, A; Millet, T; Mitrevski, J; Molina, J; Mommsen, R K; Mondal, N K; Moore, R W; Moulik, T; Muanza, G S; Mulders, M; Mulhearn, M; Mundal, O; Mundim, L; Nagy, E; Naimuddin, M; Narain, M; Naumann, N A; Neal, H A; Negret, J P; Neustroev, P; Nilsen, H; Nogima, H; Nomerotski, A; Novaes, S F; Nunnemann, T; O'Dell, V; O'Neil, D C; Obrant, G; Ochando, C; Onoprienko, D; Oshima, N; Osta, J; Otec, R; Oteroy-Garzon, G J; Owen, M; Padley, P; Pangilinan, M; Parashar, N; Park, S J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Pawloski, G; Penning, B; Perfilov, M; Peters, K; Peters, Y; Petroff, P; Petteni, M; Piegaia, R; Piper, J; Pleier, M A; Podesta-Lerma, P L M; Podstavkov, V M; Pogorelov, Y; Pol, M E; Polozov, P; Pope, B G; Popov, A V; Potter, C; Prado da Silva, W L; Prosper, H B; Protopopescu, S; Qian, J; Quadt, A; Quinn, B; Rakitine, A; Rangel, M S; Ranjan, K; Ratoff, P N; Renkel, P; Reucroft, S; Rich, P; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F; Robinson, S; Rodrigues, R F; Rominsky, M; Royon, C; Rubinov, P; Ruchti, R; Safronov, G; Sajot, G; Sánchez-Hernández, A; Sanders, M P; Santoro, A; Savage, G; Sawyer, L; Scanlon, T; Schaile, A D; Schamberger, R D; Scheglov, Y; Schellman, H; Schieferdecker, P; Schliephake, T; Schwanenberger, C; Schwartzman, A; Schwienhorst, R; Sekaric, J; Severini, H; Shabalina, E; Shamim, M; Shary, V; Shchukin, A A; Shivpuri, R K; Siccardi, V; Simák, V; Sirotenko, V; Skubic, P; Slattery, P; Smirnov, D; Snow, J; Snow, G R; Snyder, S; Söldner-Rembold, S; Sonnenschein, L; Sopczak, A; Sosebee, M; Soustruznik, K; Souza, M; Spurlock, B; Stark, J; Steele, J; Stolin, V; Stoyanova, D A; Strandberg, J; Strandberg, S; Strang, M A; Strauss, M; Strauss, E; Ströhmer, R; Strom, D; Stutte, L; Sumowidagdo, S; Svoisky, P; Sznajder, A; Talby, M; Tamburello, P; Tanasijczuk, A; Taylor, W; Temple, J; Tiller, B; Tissandier, F; Titov, M; Tokmenin, V V; Toole, T; Torchiani, I; Trefzger, T; Tsybychev, D; Tuchming, B; Tully, C; Tuts, P M; Unalan, R; Uvarov, S; Uvarov, L; Uzunyan, S; Vachon, B; vanden Berg, P J; Van Kooten, R; Van Leeuwen, W M; Varelas, N; Varnes, E W; Vasilyev, I A; Vaupel, M; Verdier, P; Vertogradov, L S; Verzocchi, M; Villeneuve-Séguier, F; Vint, P; Vokac, P; Von Törne, E; Voutilainen, M; Wagner, R; Wahl, H D; Wang, L; SWang, M H L; Warchol, J; Watts, G; Wayne, M; Weber, M; Weber, G; Wenger, A; Wermes, N; Wetstein, M; White, A; Wicke, D; Wilson, G W; Wimpenny, S J; Wobisch, M; Wood, D R; Wyatt, T R; Xie, Y; Yacoob, S; Yamada, R; Yan, M; Yasuda, T; Yatsunenko, Y A; Yip, K; Yoo, H D; Youn, S W; Yu, J; Zatserklyaniy, A; Zeitnitz, C; Zhao, T; Zhou, B; Zhu, J; Zielinski, M; Zieminska, D; Zieminski, A; Zivkovic, L; Zutshi, V; Zverev, E G
2007-01-01
Using 1 fb-1 of data from ppbar collisions at $\\sqrt{s}$=1.96 TeV at the Fermilab Tevatron collider collected by the D0 detector, we search for decays of Kaluza-Klein excitations of the graviton in the Randall-Sundrum model of extra dimensions to $e^+e^-$ and diphotons. We set 95% confidence level upper limits on the production cross section times branching fraction which translate into lower limits on the mass of the lightest excitation between 300 and 900 GeV for values of the coupling k/M(Planck) between 0.01 and 0.1.
General self-tuning solutions and no-go theorem
Energy Technology Data Exchange (ETDEWEB)
Förste, Stefan [Bethe Center for Theoretical Physics and Physikalisches Institut der Universität Bonn, Nussallee 12, 53115 Bonn (Germany); Kim, Jihn E. [Department of Physics, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Lee, Hyun Min, E-mail: forste@th.physik.uni-bonn.de, E-mail: jihnekim@gmail.com, E-mail: hyun.min.lee@kias.re.kr [School of Physics, KIAS, Seoul 130-722 (Korea, Republic of)
2013-03-01
We consider brane world models with one extra dimension. In the bulk there is in addition to gravity a three form gauge potential or equivalently a scalar (by generalisation of electric magnetic duality). We find classical solutions for which the 4d effective cosmological constant is adjusted by choice of integration constants. No go theorems for such self-tuning mechanism are circumvented by unorthodox Lagrangians for the three form respectively the scalar. It is argued that the corresponding effective 4d theory always includes tachyonic Kaluza-Klein excitations or ghosts. Known no go theorems are extended to a general class of models with unorthodox Lagrangians.
750 GeV Diphoton Resonance in Warped Geometries
Hewett, JoAnne L
2016-01-01
We examine the scenario of a warped extra dimension containing bulk SM fields in light of the observed diphoton excess at 750 GeV. We demonstrate that a bulk spin-2 graviton whose action contains localized kinetic brane terms is compatible with the excess, while being consistent with all other constraints. This model contains a single free parameter, the mass of the first gauge Kaluza-Klein excitation. The scale of physics on the IR-brane is found to lie in the range of a ~ few TeV, relevant to the gauge hierarchy.
Gravity in the brane-world for two-branes model with stabilized modulus
Energy Technology Data Exchange (ETDEWEB)
Tanaka, Takahiro; Montes, Xavier
2000-08-28
We present a complete scheme to discuss linear perturbations in the two-branes model of the Randall and Sundrum scenario with the stabilization mechanism proposed by Goldberger and Wise. We confirm that under the approximation of zero-mode truncation the induced metric on the branes reproduces that of the usual 4-dimensional Einstein gravity. We also present formulas to evaluate the mass spectrum and the contribution to the metric perturbations from all the Kaluza-Klein modes. We also conjecture that the model has tachyonic modes unless the background configuration for the bulk scalar field introduced to stabilize the distance between the two branes is monotonic in the fifth dimension.
Magnetic monopoles and relativistic cosmological models
Energy Technology Data Exchange (ETDEWEB)
Stein-Schabes, J.A.
1984-01-01
A dissertation is presented on magnetic monopoles and relativistic cosmological models. The maximum number density of monopoles in various astrophysical scenarios was investigated along with: the monopole flux in the galaxy, the allowed monopole abundance, and the formation of stable monopole orbits. Limits on the mass and lifetime of monopolonium were calculated. Boltzmann's equation was used to calculate the monopole abundance in a magnetic axisymmetric Bianchi I cosmological model, and a solution was found describing an axisymmetric Bianchi I magnetic cosmology with monopoles. New inhomogeneous solutions to Einstein's equations were found. Finally, stability and inflation in Kaluza-Klein cosmologies in d + D + 1 dimensions was studied.
Remarks on scale separation in flux vacua
Gautason, F F; Van Riet, T; Williams, M
2015-01-01
We argue that the Maldacena-Nunez no-go theorem excluding Minkowski and de Sitter vacua in flux compactifications can be extended to exclude anti-de Sitter (AdS) vacua for which the Kaluza-Klein scale is parametrically smaller than the AdS length scale. As a practical application of this observation we demonstrate that the mechanism to resolve O6 singularities in massive type IIA at the classical level is likely not to occur in AdS compactifications with scale separation. We furthermore remark that a compactification to four observable dimensions implies a large cosmological hierarchy.
Asymptotic behavior of solutions to a degenerate quasilinear parabolic equation with a gradient term
Directory of Open Access Journals (Sweden)
Huilai Li
2015-12-01
Full Text Available This article concerns the asymptotic behavior of solutions to the Cauchy problem of a degenerate quasilinear parabolic equations with a gradient term. A blow-up theorem of Fujita type is established and the critical Fujita exponent is formulated by the spacial dimension and the behavior of the coefficient of the gradient term at infinity.
On nulls of perturbed Fredholm operators and degenerate homoclinic bifurcations
Institute of Scientific and Technical Information of China (English)
无
2004-01-01
It is known that small perturbations of a Fredholm operator L have nulls of dimension not larger than dirnN(L). In this paper for any given positive integer κ≤ dimN(L)we prove that there is a perturbation of L which has an exactlyκ-dimensional null. Actually,our proof gives a construction of the perturbation. We further apply our result to concrete examples of differential equations with degenerate homoclinic orbits, showing how many independent homoclinic orbits can be bifurcated from a perturbation.
Spheroidal Degeneration of the Cornea
Directory of Open Access Journals (Sweden)
Erdem Dinç
2011-08-01
Full Text Available A thirty-one-year-old male patient presented with bilateral epiphora and stinging sensation in the cornea. Detailed history revealed that a bilateral corneal scraping had been made regarding the initial diagnosis of fungal keratitis. His bestcorrected visual acuities were 20/20 and 20/30 in right and left eyes, respectively. Biomicroscopy showed bilateral amber colored spherules in the anterior stroma of the central cornea. The diagnosis of spheroidal corneal degeneration was established and symptomatic therapy with artificial tear drops was prescribed. Ultraviolet light is widely accepted to be the main etiological factor in the pathogenesis of spheroidal degeneration. Because of difficulties in the early stages of the diagnostic process of the disease, incorrect diagnoses can be made with inappropriate interventions. (Turk J Ophthalmol 2011; 41: 264-6
Radial keratotomy associated endothelial degeneration
Directory of Open Access Journals (Sweden)
Moshirfar M
2012-02-01
Full Text Available Majid Moshirfar, Andrew Ollerton, Rodmehr T Semnani, Maylon HsuJohn A Moran Eye Center, Department of Ophthalmology and Visual Sciences, University of Utah, Salt Lake City, UT, USAPurpose: To describe the presentation and clinical course of eyes with a history of radial keratotomy (RK and varying degrees of endothelial degeneration.Methods: Retrospective case series were used.Results: Thirteen eyes (seven patients were identified with clinical findings of significant guttata and a prior history of RK. The mean age of presentation for cornea evaluation was 54.3 years (range: 38–72 years, averaging 18.7 years (range: 11–33 years after RK. The presentation of guttata varied in degree from moderate to severe. Best corrected visual acuity (BCVA ranged from 20/25 to 20/80. All patients had a history of bilateral RK, except one patient who did not develop any guttata in the eye without prior RK. No patients reported a family history of Fuch’s Dystrophy. One patient underwent a penetrating keratoplasty in one eye and a Descemet’s stripping automated endothelial keratoplasty (DSAEK in the other eye.Conclusions: RK may induce a spectrum of endothelial degeneration. In elderly patients, the findings of guttata may signify comorbid Fuch’s dystrophy in which RK incisions could potentially hasten endothelial decomposition. In these select patients with stable cornea topography and prior RK, DSAEK may successfully treat RK endothelial degeneration.Keywords: radial keratotomy, RK, Descemet’s stripping automated endothelial keratoplasty, DSAEK, guttata, endothelial degeneration, Fuch’s dystrophy
Degenerating the elliptic Schlesinger system
Aminov, G. A.; Artamonov, S. B.
2013-01-01
We study various ways of degenerating the Schlesinger system on the elliptic curve with R marked points. We construct a limit procedure based on an infinite shift of the elliptic curve parameter and on shifts of the marked points. We show that using this procedure allows obtaining a nonautonomous Hamiltonian system describing the Toda chain with additional spin sl(N, ℂ) degrees of freedom.
Radial keratotomy associated endothelial degeneration.
Moshirfar, Majid; Ollerton, Andrew; Semnani, Rodmehr T; Hsu, Maylon
2012-01-01
To describe the presentation and clinical course of eyes with a history of radial keratotomy (RK) and varying degrees of endothelial degeneration. Retrospective case series were used. Thirteen eyes (seven patients) were identified with clinical findings of significant guttata and a prior history of RK. The mean age of presentation for cornea evaluation was 54.3 years (range: 38-72 years), averaging 18.7 years (range: 11-33 years) after RK. The presentation of guttata varied in degree from moderate to severe. Best corrected visual acuity (BCVA) ranged from 20/25 to 20/80. All patients had a history of bilateral RK, except one patient who did not develop any guttata in the eye without prior RK. No patients reported a family history of Fuch's Dystrophy. One patient underwent a penetrating keratoplasty in one eye and a Descemet's stripping automated endothelial keratoplasty (DSAEK) in the other eye. RK may induce a spectrum of endothelial degeneration. In elderly patients, the findings of guttata may signify comorbid Fuch's dystrophy in which RK incisions could potentially hasten endothelial decomposition. In these select patients with stable cornea topography and prior RK, DSAEK may successfully treat RK endothelial degeneration.
On Universal Quantum Dimensions
Mkrtchyan, R L
2016-01-01
We derive universal expressions for quantum dimensions (universal characters) of some series of irreps of simple Lie algebras. This allows us to check Deligne's hypothesis on universal quantum dimensions for symmetric cube of adjoint representation.
Goparaju Purna SUDHAKAR
2014-01-01
Popularity of teams is growing in 21st Century. Organizations are getting their work done through different types of teams. Teams have proved that the collective performance is more than the sum of the individual performances. Thus, the teams have got different dimensions such as quantitative dimensions and qualitative dimensions. The Quantitative dimensions of teams such as team performance, team productivity, team innovation, team effectiveness, team efficiency, team decision making and tea...
Sudhakar, Goparaju Purna
2013-01-01
Popularity of teams is growing in 21st Century. Organizations are getting their work done through different types of teams. Teams have proved that the collective performance is more than the sum of the individual performances. Thus, the teams have got different dimensions such as quantitative dimensions and qualitative dimensions. The Quantitative dimensions of teams such as team performance, team productivity, team innovation, team effectiveness, team efficiency, team decision making and tea...
Strongly Gorenstein Flat Dimensions
Institute of Scientific and Technical Information of China (English)
Chun Xia ZHANG; Li Min WANG
2011-01-01
This article is concerned with the strongly Gorenstein flat dimensions of modules and rings.We show this dimension has nice properties when the ring is coherent,and extend the well-known Hilbert's syzygy theorem to the strongly Gorenstein flat dimensions of rings.Also,we investigate the strongly Gorenstein flat dimensions of direct products of rings and (almost)excellent extensions of rings.
The custodially protected Randall-Sundrum model. Global features and distinct flavor signatures
Energy Technology Data Exchange (ETDEWEB)
Duling, Bjoern
2010-04-19
Models with a warped extra dimension as first proposed by Randall and Sundrum offer possible solutions to the gauge hierarchy and flavor hierarchy problems. In this thesis we concentrate on the particularly well-motivated Randall-Sundrum model with custodial protection of the T parameter and the Zb{sub L} anti b{sub L} vertex and carefully work out its flavor structure. Based on these results we study how the presence of additional Kaluza-Klein states affects particle-antiparticle oscillations and rare decays and derive analytic expressions for the most relevant K and B physics observables. In the course of the ensuing global numerical analysis we conform the stringent bound on the Kaluza-Klein mass scale which is imposed by indirect CP violation in K{sup 0} - anti K{sup 0} oscillations. Yet, we are able to show that agreement with all available data on {delta}F=2 observables can be obtained for TeV-scale Kaluza-Klein masses without significant fine tuning. Furthermore we find large possible effects in CP violation in B{sub s}- anti B{sub s} oscillations as well as in rare K decays, which however are mutually exclusive. The impact on rare decay branching ratios of B mesons on the other hand turns out to be small and very challenging to measure in the near future. In addition we identify a number of distinct correlations between different observables and find that a very specific pattern of flavor violation is present. This pattern can be used to distinguish the model under consideration from other frameworks of new physics, as we demonstrate explicitly for the Littlest Higgs model with T-parity and the Standard Model with a sequential fourth generation of quarks and leptons. (orig.)
Dimensions of Creative Evaluation
DEFF Research Database (Denmark)
Christensen, Bo; Ball, Linden J.
2016-01-01
We examined evaluative reasoning taking place during expert ‘design critiques’. We focused on key dimensions of creative evaluation (originality, functionality and aesthetics) and ways in which these dimensions impact reasoning strategies and suggestions offered by experts for how the student could...... continue. Each dimension was associated with a specific underpinning ‘logic’ determining how these dimensions were evaluated in practice. Our analysis clarified how these dimensions triggered reasoning strategies such as running mental simulations or making design suggestions, ranging from ‘go...
Malm, Raoul; Schmell, Christoph
2015-01-01
We calculate the electro- and chromomagnetic dipole coefficients $C_{7\\gamma,8g}$ and $\\tilde C_{7\\gamma,8g}$ in the context of the minimal Randall-Sundrum (RS) model with a Higgs sector localized on the IR brane using the five-dimensional (5D) approach, where the coefficients are expressed in terms of integrals over 5D propagators. Since we keep the full dependence on the Yukawa matrices, the integral expressions are formally valid to all orders in $v^2/M_{\\rm KK}^2$. In addition we relate our results to the expressions obtained in the Kaluza-Klein (KK) decomposed theory and show the consistency in both pictures analytically and numerically, which presents a non-trivial cross-check. In Feynman-'t Hooft gauge, the dominant corrections from virtual KK modes arise from the scalar parts of the $W^\\pm$-boson penguin diagrams, including the contributions from the scalar component of the 5D gauge-boson field and from the charged Goldstone bosons in the Higgs sector. The size of the KK corrections depends on the par...
Disc degeneration: current surgical options
Directory of Open Access Journals (Sweden)
C Schizas
2010-10-01
Full Text Available Chronic low back pain attributed to lumbar disc degeneration poses a serious challenge to physicians. Surgery may be indicated in selected cases following failure of appropriate conservative treatment. For decades, the only surgical option has been spinal fusion, but its results have been inconsistent. Some prospective trials show superiority over usual conservative measures while others fail to demonstrate its advantages. In an effort to improve results of fusion and to decrease the incidence of adjacent segment degeneration, total disc replacement techniques have been introduced and studied extensively. Short-term results have shown superiority over some fusion techniques. Mid-term results however tend to show that this approach yields results equivalent to those of spinal fusion. Nucleus replacement has gained some popularity initially, but evidence on its efficacy is scarce. Dynamic stabilisation, a technique involving less rigid implants than in spinal fusion and performed without the need for bone grafting, represents another surgical option. Evidence again is lacking on its superiority over other surgical strategies and conservative measures. Insertion of interspinous devices posteriorly, aiming at redistributing loads and relieving pain, has been used as an adjunct to disc removal surgery for disc herniation. To date however, there is no clear evidence on their efficacy. Minimally invasive intradiscal thermocoagulation techniques have also been tried, but evidence of their effectiveness is questioned. Surgery using novel biological solutions may be the future of discogenic pain treatment. Collaboration between clinicians and basic scientists in this multidisciplinary field will undoubtedly shape the future of treating symptomatic disc degeneration.
Regularized degenerate multi-solitons
Correa, Francisco
2016-01-01
We report complex PT-symmetric multi-soliton solutions to the Korteweg de-Vries equation that asymptotically contain one-soliton solutions, with each of them possessing the same amount of finite real energy. We demonstrate how these solutions originate from degenerate energy solutions of the Schroedinger equation. Technically this is achieved by the application of Darboux-Crum transformations involving Jordan states with suitable regularizing shifts. Alternatively they may be constructed from a limiting process within the context Hirota's direct method or on a nonlinear superposition obtained from multiple Baecklund transformations. The proposed procedure is completely generic and also applicable to other types of nonlinear integrable systems.
Degenerate Neutrinos and CP Violation
Ioannisian, A N
2003-01-01
We have studied mixing and masses of three left handed Majorana neutrinos in the model, which assumes exactly degenerate neutrino masses at some "neutrino unification" scale. Such a simple theoretical ansatz naturally leads to quasidegenerate neutrinos. The neutrino mass splittings induced by renormalization effects. In the model we found that the parameters of the neutrino physics (neutrino mass spectrum, mixing angles and CP violation phases) are strongly intercorrelated to each other. From these correlations we got strong bounds on the parameters which could be checked in the oscillation experiments.
Radiative seesaw and degenerate neutrinos
Bajc, B; Bajc, Borut; Senjanovic, Goran
2005-01-01
The radiative see-saw mechanism of Witten generates the right-handed neutrino masses in SO(10) with the spinorial 16_H Higgs field. We study here analytically the 2nd and 3rd generations for the minimal Yukawa structure containing 10_H and 120_H Higgs representations. In the approximation of small 2nd generation masses and gauge loop domination we find the following results : (1) b-tau unification, (2) natural coexistence between large theta_l and small theta_q, (3) degenerate neutrinos.
Black Strings, Black Rings and State-space Manifold
Bellucci, Stefano
2011-01-01
State-space geometry is considered, for diverse three and four parameter non-spherical horizon rotating black brane configurations, in string theory and $M$-theory. We have explicitly examined the case of unit Kaluza-Klein momentum $D_1D_5P$ black strings, circular strings, small black rings and black supertubes. An investigation of the state-space pair correlation functions shows that there exist two classes of brane statistical configurations, {\\it viz.}, the first category divulges a degenerate intrinsic equilibrium basis, while the second yields a non-degenerate, curved, intrinsic Riemannian geometry. Specifically, the solutions with finitely many branes expose that the two charged rotating $D_1D_5$ black strings and three charged rotating small black rings consort real degenerate state-space manifolds. Interestingly, arbitrary valued $M_5$-dipole charged rotating circular strings and Maldacena Strominger Witten black rings exhibit non-degenerate, positively curved, comprehensively regular state-space con...
Macular Degeneration Prevention and Risk Factors
... Grant Terms & Conditions Patent & Intellectual Property Policy For Current Awardees FAQs Our Funding Philosophy ... Alzheimer’s Disease Research Macular Degeneration Research National Glaucoma Research ...
[Pathogenesis of age-related macular degeneration].
Kaarniranta, Kai; Seitsonen, Sanna; Paimela, Tuomas; Meri, Seppo; Immonen, Ilkka
2009-01-01
Age-related macular degeneration is a multiform disease of the macula, the region responsible for detailed central vision. In recent years, plenty of new knowledge of the pathogenesis of this disease has been obtained, and the treatment of exudative macular degeneration has greatly progressed. The number of patients with age-related macular degeneration will multiply in the following decades, because knowledge of mechanisms of development of macular degeneration that could be subject to therapeutic measures is insufficient. Central underlying factors are genetic inheritance, exposure of the retina to chronic oxidative stress and accumulation of inflammation-inducing harmful proteins into or outside of retinal cells.
DEFF Research Database (Denmark)
Lykke, Marianne; Jantzen, Christian
2016-01-01
The present study develops a set of 10 dimensions based on a systematic understanding of the concept of experience as a holistic psychological. Seven of these are derived from a psychological conception of what experiencing and experiences are. Three supplementary dimensions spring from...... the observation that experiences apparently have become especially valuable phenomena in Western societies. The 10 dimensions are tried out in a field study at the Center for Art and Media (ZKM) in Germany with the purpose to study their applicability in the evaluation of interactive sound archives. 29 walk......-alongs were carried out with 58 museums visitors. Our analysis showed that it was possible to identify the 10 experience dimensions in the study material. Some dimensions were expressed more frequently than others. The distribution of expressed dimensions and the content of the user comments provided a clear...
Institute of Scientific and Technical Information of China (English)
无
2005-01-01
In this paper, we are interested in the following general question: Given a module Mwhich has finite hollow dimension and which has a finite collection of submodules Ki (1≤i≤n) such that M=K1+... +Kn, can we find an expression for the hollow dimension of Min terms of hollow dimensions of modules built up in some way from K1 Kn? We prove the following theorem:Let Mbe an amply supplemented module having finite hollow dimension and let Ki (1≤i≤n) be a finite collection of submodules of Msuch that M=K1+...+Kn. Then the hollow dimension h(M) of Mis the sum of the hollow dimensions of Ki (1≤i≤n) ifand only if Ki is a supplement of K1+...+Ki-1+Ki+1+...+Kn in Mfor each 1≤i≤n.
Structure of Degenerate Block Algebras
Institute of Scientific and Technical Information of China (English)
Linsheng Zhu; Daoji Meng
2003-01-01
Given a non-trivial torsion-free abelian group (A,+,0), a field F of characteristic 0, and a non-degenerate bi-additive skew-symmetric map φ :A × A → F, we define a Lie algebra ∑ = ∑(A, φ) over F with basis {ex | x ∈ A\\{0}}and Lie product [ex, ey] = φ(x, y)ex+y. We show that ∑ is endowed uniquely with a non-degenerate symmetric invariant bilinear form and the derivation algebra Der ∑ of ∑ is a complete Lie algebra. We describe the double extension D(∑, T) of ∑ by T, where T is spanned by the locally finite derivations of ∑, and determine the second cohomology group H2(D(∑,T),F) using anti-derivations related to the form on D(∑, T). Finally, we compute the second Leibniz cohomology groups HL2(∑, F) and HL2(D(∑, T), F).
DEFF Research Database (Denmark)
Høskuldsson, Agnar
1996-01-01
Determination of the proper dimension of a given linear model is one of the most important tasks in the applied modeling work. We consider here eight criteria that can be used to determine the dimension of the model, or equivalently, the number of components to use in the model. Four...... the basic problems in determining the dimension of linear models. Then each of the eight measures are treated. The results are illustrated by examples....
Multiple dimensions of performance
Torenvlied, René
2013-01-01
This presentation considers the multiple dimensions of performance in performance studies, and potentially contradicting effects of different management strategies on separate indicators of performance
Directory of Open Access Journals (Sweden)
Quznetsov G.
2014-10-01
Full Text Available Each vector of state has its own corresponing element of the CayleyDickson algebra. Properties of a state vector require that this algebra was a normalized division algebra. By the Hurwitz and Frobenius theorems maximal dimension of s uch algebra is 8. Con- sequently, a dimension of corresponding complex state vectors is 4, and a dimension of the Clifford set elements is 4 × 4. Such set contains 5 matrices — among them — 3-diagonal. Hence, a dimension of the dot events space is equal to 3 + 1.
THE DISTRIBUTIONAL DIMENSION OF FRACTALS
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
In the book [1] H.Triebel introduces the distributional dimension of fractals in and distributional dimension, respectively. Thus we might say that the distributional dimension is an analytical definition for Hausdorff dimension. Therefore we can study Hausdorff dimension through the distributional dimension analytically.By discussing the distributional dimension, this paper intends to set up a criterion for estimating the upper and lower bounds of Hausdorff dimension analytically. Examples illustrating the criterion are included in the end.
DEFF Research Database (Denmark)
Lykke, Marianne; Jantzen, Christian
2016-01-01
The present study develops a set of 10 dimensions based on a systematic understanding of the concept of experience as a holistic psychological. Seven of these are derived from a psychological conception of what experiencing and experiences are. Three supplementary dimensions spring from the obser...
Gorenstein homological dimensions
DEFF Research Database (Denmark)
Holm, Henrik Granau
2004-01-01
In basic homological algebra, the projective, injective and 2at dimensions of modules play an important and fundamental role. In this paper, the closely related Gorenstein projective, Gorenstein injective and Gorenstein 2at dimensions are studied. There is a variety of nice results about Gorenstein...
Gorenstein homological dimensions
DEFF Research Database (Denmark)
Holm, Henrik Granau
2004-01-01
In basic homological algebra, the projective, injective and 2at dimensions of modules play an important and fundamental role. In this paper, the closely related Gorenstein projective, Gorenstein injective and Gorenstein 2at dimensions are studied. There is a variety of nice results about Gorenstein...
Universal Extra Dimension models with right-handed neutrinos
Matsumoto, Shigeki; Senami, Masato; Yamanaka, Masato
2008-01-01
Relic abundance of dark matter is investigated in the framework of universal extra dimension (UED) models with right-handed neutrinos. These models are free from the KK graviton problem in the minimal UED model. The first KK particle of the right-handed neutrino is a dark matter candidate in this framework. When ordinary neutrino masses are large enough such as the degenerate mass spectrum case, the dark matter relic abundance can increase significantly. The scale of the extra dimension consistent with cosmological observations can be 500 GeV in the minimal setup of UED models with right-handed neutrinos.
Genetic association studies in lumbar disc degeneration
DEFF Research Database (Denmark)
Eskola, Pasi J; Lemmelä, Susanna; Kjaer, Per
2012-01-01
Low back pain is associated with lumbar disc degeneration, which is mainly due to genetic predisposition. The objective of this study was to perform a systematic review to evaluate genetic association studies in lumbar disc degeneration as defined on magnetic resonance imaging (MRI) in humans....
Degenerated differential pair with controllable transconductance
Mensink, Clemens; Mensink, Clemens H.J.; Nauta, Bram
1998-01-01
A differential pair with input transistors and provided with a variable degeneration resistor. The degeneration resistor comprises a series arrangement of two branches of coupled resistors which are shunted in mutually corresponding points by respective control transistors whose gates are interconne
Regularized degenerate multi-solitons
Correa, Francisco; Fring, Andreas
2016-09-01
We report complex {P}{T} -symmetric multi-soliton solutions to the Korteweg de-Vries equation that asymptotically contain one-soliton solutions, with each of them possessing the same amount of finite real energy. We demonstrate how these solutions originate from degenerate energy solutions of the Schrödinger equation. Technically this is achieved by the application of Darboux-Crum transformations involving Jordan states with suitable regularizing shifts. Alternatively they may be constructed from a limiting process within the context Hirota's direct method or on a nonlinear superposition obtained from multiple Bäcklund transformations. The proposed procedure is completely generic and also applicable to other types of nonlinear integrable systems.
Naturalness of nearly degenerate neutrinos
Casas, J A; Ibarra, Alejandro; Navarro, I
1999-01-01
If neutrinos are to play a relevant cosmological role, they must be essentially degenerate. We study whether radiative corrections can or cannot be responsible for the small mass splittings, in agreement with all the available experimental data. We perform an exhaustive exploration of the bimaximal mixing scenario, finding that (i) the vacuum oscillations solution to the solar neutrino problem is always excluded; (ii) if the mass matrix is produced by a see-saw mechanism, there are large regions of the parameter space consistent with the large angle MSW solution, providing a natural origin for the Delta m^2_{sol} << Delta m^2_{atm} hierarchy; (iii) the bimaximal structure becomes then stable under radiative corrections. We also provide analytical expressions for the mass splittings and mixing angles and present a particularly simple see-saw ansatz consistent with all the observations.
Degenerate doping of metallic anodes
Friesen, Cody A; Zeller, Robert A; Johnson, Paul B; Switzer, Elise E
2015-05-12
Embodiments of the invention relate to an electrochemical cell comprising: (i) a fuel electrode comprising a metal fuel, (ii) a positive electrode, (iii) an ionically conductive medium, and (iv) a dopant; the electrodes being operable in a discharge mode wherein the metal fuel is oxidized at the fuel electrode and the dopant increases the conductivity of the metal fuel oxidation product. In an embodiment, the oxidation product comprises an oxide of the metal fuel which is doped degenerately. In an embodiment, the positive electrode is an air electrode that absorbs gaseous oxygen, wherein during discharge mode, oxygen is reduced at the air electrode. Embodiments of the invention also relate to methods of producing an electrode comprising a metal and a doped metal oxidation product.
Heterotic-type IIA duality and degenerations of K3 surfaces
Energy Technology Data Exchange (ETDEWEB)
Braun, A.P. [Department of Mathematics, University of Oxford,Andrew Wiles Building, Woodstock Rd, Oxford OX2 6GG (United Kingdom); Watari, T. [Kavli Institute for the Physics and Mathematics of the Universe, University of Tokyo,Kashiwano-ha 5-1-5, 277-8583 (Japan)
2016-08-04
We study the duality between four-dimensional N=2 compactifications of heterotic and type IIA string theories. Via adiabatic fibration of the duality in six dimensions, type IIA string theory compactified on a K3-fibred Calabi-Yau threefold has a potential heterotic dual compactification. This adiabatic picture fails whenever the K3 fibre degenerates into multiple components over points in the base of the fibration. Guided by monodromy, we identify such degenerate K3 fibres as solitons generalizing the NS5-brane in heterotic string theory. The theory of degenerations of K3 surfaces can then be used to find which solitons can be present on the heterotic side. Similar to small instanton transitions, these solitons escort singular transitions between different Calabi-Yau threefolds. Starting from well-known examples of heterotic-type IIA duality, such transitions can take us to type IIA compactifications with unknown heterotic duals.
Thick Brane Worlds Arising From Pure Geometry
Cardenas, R; Cardenas, Rolando; Quiros, Israel
2002-01-01
We study a non-Riemannian modification of 5-dimensional Kaluza-Klein theory. In our proposal the Riemannian structure of the five-dimensional manifold is replaced by a Weyl-integrable one. In this context a 4-dimensional Poincar$\\grave{e}$ invariant solution is studied. A spacetime structure with two thick (smooth) branes separated in the extra dimension arises. The massless graviton is located in one of the thick branes at the origin, meanwhile the matter degrees of freedom are confined to the other brane. Due to the small overlap of the graviton's wave-function with the second thick brane, the model accounts for a resolution of the mass hierarchy problem a la Randall-Sundrum. Although, initially, no assumptions are made about the topology of the extra dimension, the solution found yields an extra space that is effectivelly compact and respects $Z_2$ symmetry. Unlike other models with branes, the spectrum of massive Kaluza-Klein states is quantized and free of tachyonic modes.
DEFF Research Database (Denmark)
Dalsgaard, Christian; Thestrup, Klaus
2015-01-01
as a matter of engaging educational activities in sociocultural practices of a surrounding society. Openness is not only a matter of opening up the existing, but of developing new educational practices that interact with society. The paper outlines three pedagogical dimensions of openness: transparency...... practices. Openness as joint engagement in the world aims at establishing interdependent collaborative relationships between educational institutions and external practices. To achieve these dimensions of openness, educational activities need to change and move beyond the course as the main format...... for openness. With examples from a university case, the paper discusses how alternative pedagogical formats and educational technologies can support the three dimensions of openness....
Rucker, Rudy
2014-01-01
""This is an invigorating book, a short but spirited slalom for the mind."" - Timothy Ferris, The New York Times Book Review ""Highly readable. One is reminded of the breadth and depth of Hofstadter's Gödel, Escher, Bach."" - Science""Anyone with even a minimal interest in mathematics and fantasy will find The Fourth Dimension informative and mind-dazzling... [Rucker] plunges into spaces above three with a zest and energy that is breathtaking."" - Martin Gardner ""Those who think the fourth dimension is nothing but time should be encouraged to read The Fourth Dimension, along with anyone else
Directory of Open Access Journals (Sweden)
Goparaju Purna SUDHAKAR
2014-01-01
Full Text Available Popularity ofteams is growing in 21st Century. Organizations are getting theirwork done through different types of teams. Teams have proved that thecollective performance is more than the sum of the individual performances.Thus, the teams have got different dimensions such as quantitative dimensionsand qualitative dimensions. The Quantitative dimensions of teams such as teamperformance, team productivity, team innovation, team effectiveness, teamefficiency, team decision making and team conflicts and Qualitative dimensionsof teams such as team communication, team coordination, team cooperation, teamcohesion, team climate, team creativity, team leadership and team conflictshave been discussed in this article.
Dimension control of Superradiance
Hill, Tyler; Hui Deng Collaboration; Barry C. Sanders Collaboration
2016-05-01
We develop a theory for quantum dipole-dipole coupling when the electromagnetic fields are confined to an open line, open plane, or open space, commensurate with experimental capability for collective atomic effects subject to dimensional confinement. Our mathematical model naturally interpolates for all real dimension between one dimension for the line to three dimensions for open space. We show how superradiant emission can be controlled by dimensional confinement, including near-field and dipole-orientation effects, and we propose a two-dimensional confinement experiment to test our theory's efficacy. University of Michigan.
DEFF Research Database (Denmark)
Due, Jesper Jørgen; Madsen, Jørgen Steen; Jensen, Carsten Strøby
En analyse af EU's institutioner og udviklingen af den sociale dimension i forbindelse med etbaleringen af det indre marked med særlig henblik på effekterne på det danske aftalesystem.......En analyse af EU's institutioner og udviklingen af den sociale dimension i forbindelse med etbaleringen af det indre marked med særlig henblik på effekterne på det danske aftalesystem....
Modified gravitational instability of degenerate and non-degenerate dusty plasma
Jain, Shweta; Sharma, Prerana
2016-09-01
The gravitational instability of strongly coupled dusty plasma (SCDP) is studied considering degenerate and non-degenerate dusty plasma situations. The SCDP system is assumed to be composed of the electrons, ions, neutrals, and strongly coupled dust grains. First, in the high density regime, due to small interparticle distance, the electrons are considered degenerate, whereas the neutrals, dust grains, and ions are treated non-degenerate. In this case, the dynamics of inertialess electrons are managed by Fermi pressure and Bohm potential, while the inertialess ions are by only thermal pressure. Second, in the non-degenerate regime, both the electrons and ions are governed by the thermal pressure. The generalized hydrodynamic model and the normal mode analysis technique are employed to examine the low frequency waves and gravitational instability in both degenerate and non-degenerate cases. The general dispersion relation is discussed for a characteristic timescale which provides two regimes of frequency, i.e., hydrodynamic regime and kinetic regime. Analytical solutions reveal that the collisions reduce the growth rate and have a strong impact on structure formation in both degenerate and non-degenerate circumstances. Numerical estimation on the basis of observed parameters for the degenerate and non-degenerate cases is presented to show the effects of dust-neutral collisions and dust effective velocity in the presence of polarization force. The values of Jeans length and Jeans mass have been estimated for degenerate white dwarfs as Jeans length L J = 1.3 × 10 5 cm and Jeans mass M J = 0.75 × 10 - 3 M⊙ and for non-degenerate laboratory plasma Jeans length L J = 6.86 × 10 16 cm and Jeans mass M J = 0.68 × 10 10 M⊙. The stability of the SCDP system is discussed using the Routh-Hurwitz criterion.
DeLucca, John F; Peloquin, John M; Smith, Lachlan J; Wright, Alexander C; Vresilovic, Edward J; Elliott, Dawn M
2016-08-01
Geometry is an important indicator of disc mechanical function and degeneration. While the geometry and associated degenerative changes in the nucleus pulposus and the annulus fibrosus are well-defined, the geometry of the cartilage endplate (CEP) and its relationship to disc degeneration are unknown. The objectives of this study were to quantify CEP geometry in three dimensions using an MRI FLASH imaging sequence and evaluate relationships between CEP geometry and age, degeneration, spinal level, and overall disc geometry. To do so, we assessed the MRI-based measurements for accuracy and repeatability. Next, we measured CEP geometry across a larger sample set and correlated CEP geometric parameters to age, disc degeneration, level, and disc geometry. The MRI-based measures resulted in thicknesses (0.3-1 mm) that are comparable to prior measurements of CEP thickness. CEP thickness was greatest at the anterior/posterior (A/P) margins and smallest in the center. The CEP A/P thickness, axial area, and lateral width decreased with age but were not related to disc degeneration. Age-related, but not degeneration-related, changes in geometry suggest that the CEP may not follow the progression of disc degeneration. Ultimately, if the CEP undergoes significant geometric changes with aging and if these can be related to low back pain, a clinically feasible translation of the FLASH MRI-based measurement of CEP geometry presented in this study may prove a useful diagnostic tool. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1410-1417, 2016.
Hirshberg, Ilan; Szabó, Gábor; Winter, Wilhelm; Wu, Jianchao
2017-07-01
We introduce a notion of Rokhlin dimension for one parameter automorphism groups of {C^*}-algebras. This generalizes Kishimoto's Rokhlin property for flows, and is analogous to the notion of Rokhlin dimension for actions of the integers and other discrete groups introduced by the authors and Zacharias in previous papers. We show that finite nuclear dimension and absorption of a strongly self-absorbing {C^*}-algebra are preserved under forming crossed products by flows with finite Rokhlin dimension, and that these crossed products are stable. Furthermore, we show that a flow on a commutative {C^*}-algebra arising from a free topological flow has finite Rokhlin dimension, whenever the spectrum is a locally compact metrizable space with finite covering dimension. For flows that are both free and minimal, this has strong consequences for the associated crossed product {C^{*}}-algebras: Those containing a non-zero projection are classified by the Elliott invariant (for compact manifolds this consists of topological {K}-theory together with the space of invariant probability measures and a natural pairing given by the Ruelle-Sullivan map).
A Monte Carlo algorithm for degenerate plasmas
Energy Technology Data Exchange (ETDEWEB)
Turrell, A.E., E-mail: a.turrell09@imperial.ac.uk; Sherlock, M.; Rose, S.J.
2013-09-15
A procedure for performing Monte Carlo calculations of plasmas with an arbitrary level of degeneracy is outlined. It has possible applications in inertial confinement fusion and astrophysics. Degenerate particles are initialised according to the Fermi–Dirac distribution function, and scattering is via a Pauli blocked binary collision approximation. The algorithm is tested against degenerate electron–ion equilibration, and the degenerate resistivity transport coefficient from unmagnetised first order transport theory. The code is applied to the cold fuel shell and alpha particle equilibration problem of inertial confinement fusion.
Horizon Supertranslation and Degenerate Black Hole Solution
Cai, Rong-Gen; Zhang, Yun-Long
2016-01-01
In this note we first review the degenerate vacua arising from the BMS symmetries. According to the discussion in [1] one can define BMS-analogous supertranslation and superrotation for spacetime with black hole in Gaussian null coordinates. In the leading and subleading orders of near horizon approximation, the infinitely degenerate black hole solutions are derived by considering Einstein equations with or without cosmological constant, and they are related to each other by the diffeomorphism generated by horizon supertranslation. Higher order results and degenerate Rindler horizon solutions also are given in appendices.
A variational principle for the Hausdorff dimension of fractal sets
DEFF Research Database (Denmark)
Olsen, Lars; Cutler, Colleen D.
1994-01-01
Matematik, fraktal (fractal), Hausdorff dimension, Renyi dimension, pakke dimension (packing dimension)......Matematik, fraktal (fractal), Hausdorff dimension, Renyi dimension, pakke dimension (packing dimension)...
Genetics of frontotemporal lobar degeneration
Directory of Open Access Journals (Sweden)
Aswathy P
2010-10-01
Full Text Available Frontotemporal lobar degeneration (FTLD is a highly heterogenous group of progressive neurodegenerative disorders characterized by atrophy of prefrontal and anterior temporal cortices. Recently, the research in the field of FTLD has gained increased attention due to the clinical, neuropathological, and genetic heterogeneity and has increased our understanding of the disease pathogenesis. FTLD is a genetically complex disorder. It has a strong genetic basis and 50% of patients show a positive family history for FTLD. Linkage studies have revealed seven chromosomal loci and a number of genes including MAPT, PGRN, VCP, and CHMB-2B are associated with the disease. Neuropathologically, FTLD is classified into tauopathies and ubiquitinopathies. The vast majority of FTLD cases are characterized by pathological accumulation of tau or TDP-43 positive inclusions, each as an outcome of mutations in MAPT or PGRN, respectively. Identification of novel proteins involved in the pathophysiology of the disease, such as progranulin and TDP-43, may prove to be excellent biomarkers of disease progression and thereby lead to the development of better therapeutic options through pharmacogenomics. However, much more dissections into the causative pathways are needed to get a full picture of the etiology. Over the past decade, advances in research on the genetics of FTLD have revealed many pathogenic mutations leading to different clinical manifestations of the disease. This review discusses the current concepts and recent advances in our understanding of the genetics of FTLD.
Quantum unique ergodicity on locally symmetric spaces: the degenerate lift
Silberman, Lior
2011-01-01
Given a measure $\\bar\\mu$ on a locally symmetric space $Y=\\Gamma\\backslash G/K$, obtained as a weak-{*} limit of probability measures associated to eigenfunctions of the ring of invariant differential operators, we construct a measure $\\mu$ on the homogeneous space $X=\\Gamma\\backslash G$ which lifts $\\bar\\mu$ and which is invariant by a connected subgroup $A_{1}\\subset A$ of positive dimension, where $G=NAK$ is an Iwasawa decomposition. If the functions are, in addition, eigenfunctions of the Hecke operators, then $\\mu$ is also the limit of measures associated to Hecke eigenfunctions on $X$. This generalizes previous results of the author and A.\\ Venkatesh to the case of "degenerate" limiting spectral parameters.
Vitelliform macular degeneration associated with mitochondrial myopathy.
Modi, G; Heckman, J M; Saffer, D
1992-01-01
A patient with mitochondrial myopathy is described. Examination of his fundus revealed bilateral vitelliform degeneration of the maculae. This lesion is a focal abnormality of the retinal pigment epithelium and may be a manifestation of the underlying mitochondrial disease.
Magnetic resonance imaging of intervertebral disc degeneration
Energy Technology Data Exchange (ETDEWEB)
Maeda, Hiroshi; Noguchi, Masao (Kitakyushu City Yahata Hospital, Fukuoka (Japan)); Kira, Hideaki; Fujiki, Hiroshi; Shimokawa, Isao; Hinoue, Kaichi
1993-02-01
The aim of this study was to correlate the degree of lumbar intervertebral disc degeneration with findings of magnetic resonance imaging (MRI). Seventeen autopsied (from 7 patients) and 21 surgical (from 20 patients) intervertebral discs were used as specimens for histopathological examination. In addition, 21 intervertebral discs were examined on T2-weighted images. Histopathological findings from both autopsied and surgical specimens were well correlated with MRI findings. In particular, T2-weighted images reflected increased collagen fibers and rupture within the fibrous ring accurately. However, when severely degenerated intervertebral discs and hernia protruding the posterior longitudinal ligament existed, histological findings were not concordant well with T2-weighted images. Morphological appearances of autopsy specimens, divided into four on T2-weighted images, were well consistent with histological degeneration. This morphological classification, as shown on T2-weighted images, could also be used in the evaluation of intervertebral disc degeneration. (N.K.).
Degenerate primer design for highly variable genomes.
Li, Kelvin; Shrivastava, Susmita; Stockwell, Timothy B
2015-01-01
The application of degenerate PCR primers towards target amplification and sequencing is a useful technique when a population of organisms under investigation is evolving rapidly, or is highly diverse. Degenerate bases in these primers are specified with ambiguity codes that represent alternative nucleotide configurations. Degenerate PCR primers allow the simultaneous amplification of a heterogeneous population by providing a mixture of PCR primers each of which anneal to an alternative genotype found in the isolated sample. However, as the number of degenerate bases specified in a pair of primers rises, the likelihood of amplifying unwanted alternative products also increases. These alternative products may confound downstream data analyses if their levels begin to obfuscate the desired PCR products. This chapter describes a set of computational methodologies that may be used to minimize the degeneracy of designed primers, while still maximizing the proportion of genotypes assayed in the targeted population.
DEFF Research Database (Denmark)
Borstnik, N. M.; Nielsen, Holger Frits Bech
2008-01-01
The genuine Kaluza-Klein-like theories-with no fields in addition to gravity-have difficulties with the existence of massless spinors after the compactification of some space dimensions [E. Witten, Nucl. Phys. B 186 (1981) 412; E. Witten, Fermion quantum numbers in Kaluza-Klein theories, Princeton...... Technical Rep. PRINT-83-1056, October 1983]. We proposed in [N.S. Mankoc Borštnik, H.B. Nielsen, Phys. Lett. B 633 (2006) 771, hep-th/0509101; N.S. Mankoc Borštnik, H.B. Nielsen, hep-th/0311037] a boundary condition for spinors in (1+5) compactified on a flat disk that ensures masslessness of spinors (with...... all positive half integer charges) in d=(1+3) as well as their chiral coupling to the corresponding background gauge gravitational field. In this Letter we study the same toy model, proposing a boundary condition allowing a massless spinor of one handedness and only one charge (1/2) and infinitely...
Search with the CMS detector for heavy resonances decaying into an electron pair
Clerbaux, Barbara; Collard, Caroline; Miné, Philippe
2006-01-01
This note presents the CMS experiment potential to discover heavy resonances decaying into an electron-positron pair, such as Kaluza-Klein excitations of a Z or graviton boson predicted in extra dimension models (the TeV^-1 model and the Randall-Sundrum model), or as neutral heavy Z' boson predicted by Grand Unified Theories. Full and fast simulation and reconstruction are used to investigate these productions, with the pileup condition corresponding to a luminosity equal to 2 times 10^ 33; mathrm cm ^ -2 mathrm s ^ -1 . For an integrated luminosity of 60 fbinv, a 5 sigma discovery limit has been obtained for a mass of 5.9 tevct in the case of Kaluza-Klein excitation Z boson production. For the Randall-Sundrum graviton production, the limit is found for graviton masses of 1.8 tevct with a coupling parameter constant c=0.01 and 4.1 tevct for c=0.1 . For the six Z' models considered here, the 5 sigma discovery limit ranges for masses from 3.6 tevct (rm Z_psi) to 4.6 tevct (rm Z_ALRM).
Search for light custodians in a clean decay channel at the LHC
de Sandes, H
2008-01-01
Models of warped extra dimensions with custodial symmetry usually predict the existence of a light Kaluza-Klein fermion arising as a partner of the right-handed top quark, sometimes called light custodians which we will denote $\\tilde{b}_R$. The production of these particles at the LHC can give rise to multi-W events which could be observed in same-sign dilepton channels, but its mass reconstruction is challenging. In this letter we study the possibility of finding a signal for the pair production of this new particle at the LHC focusing on a rarer, but cleaner decay mode of a light custodian into a $Z$ boson and a $b$-quark. In this mode it would be possible to reconstruct the light custodian mass. In addition to the dominant standard model QCD production processes, we include the contribution of a Kaluza-Klein gluon first mode. We find that the $\\tilde{b}_R$ stands out from the background as a peak in the $b Z$ invariant mass. However, when taking into account only the electronic and muonic decay modes of t...
Enhanced Higgs Mass in Compact Supersymmetry
Tobioka, Kohsaku; Murayama, Hitoshi
2015-01-01
The current LHC results make weak scale supersymmetry difficult due to relatively heavy mass of the discovered Higgs boson and the null results of new particle searches. Geometrical supersymmetry breaking from extra dimensions, Scherk-Schwarz mechanism, is possible to accommodate such situations. A concrete example, the Compact Supersymmetry model, has a compressed spectrum ameliorating the LHC bounds and large mixing in the top and scalar top quark sector with $|A_t|\\sim 2m_{\\tilde{t}}$ which radiatively raises the Higgs mass. While the zero mode contributions of the model has been considered, in this paper we calculate the Kaluza-Klein tower effect to the Higgs mass. Although such contributions are naively expected to be as small as a percent level for 10 TeV Kaluza-Klein modes, we find the effect significantly enhances the radiative correction to the Higgs quartic coupling by from 10 to 50 %. This is mainly because the top quark wave function is pushed out from the brane, which makes the top Yukawa couplin...
Enhanced Higgs mass in Compact Supersymmetry
Tobioka, Kohsaku; Kitano, Ryuichiro; Murayama, Hitoshi
2016-04-01
The current LHC results make weak scale supersymmetry difficult due to relatively heavy mass of the discovered Higgs boson and the null results of new particle searches. Geometrical supersymmetry breaking from extra dimensions, Scherk-Schwarz mechanism, is possible to accommodate such situations. A concrete example, the Compact Supersymmetry model, has a compressed spectrum ameliorating the LHC bounds and large mixing in the top and scalar top quark sector with |{A}_t|˜ 2{m}_{tilde{t}} which radiatively raises the Higgs mass. While the zero mode contribution of the model has been considered, in this paper we calculate the Kaluza-Klein tower effect to the Higgs mass. Although such contributions are naively expected to be as small as a percent level for 10 TeV Kaluza-Klein modes, we find the effect significantly enhances the radiative correction to the Higgs quartic coupling by from 10 to 50%. This is mainly because the top quark wave function is pushed out from the brane, which makes the top mass depend on higher powers in the Higgs field. As a result the Higgs mass is enhanced up to 15 GeV from the previous calculation. We also show the whole parameter space is testable at the LHC run II.
Effective action of 6D F-Theory with U(1) factors: Rational sections make Chern-Simons terms jump
Grimm, Thomas W; Keitel, Jan
2013-01-01
We derive the six-dimensional (1,0) effective action arising from F-theory on an elliptically fibered Calabi-Yau threefold with multiple sections. The considered theories admit both non-Abelian and Abelian gauge symmetries. Our derivation employs the M-theory to F-theory duality in five-dimensions after circle reduction. Five-dimensional gauge and gravitational Chern-Simons terms are shown to arise at one-loop by integrating out massive Coulomb branch and Kaluza-Klein modes. In the presence of a non-holomorphic zero section, we find an improved systematic for performing the F-theory limit by using the concept of the extended relative Mori cone. In this situation Kaluza-Klein modes can become lighter than Coulomb branch modes and a jump in the Chern-Simons levels occurs. By determining Chern-Simons terms for various threefold examples we are able to compute the complete six-dimensional charged matter spectrum and show consistency with six-dimensional anomalies.
Heun equation in a 5D sine-Gordon brane-world model with dilaton
Energy Technology Data Exchange (ETDEWEB)
Cunha, M.S.; Christiansen, H. [Universidade Estadual do Ceara (GFT/UECE), CE (Brazil). Grupo de Fisica Teorica
2011-07-01
Full text: In a brane-world scenario we find the propagation modes of the gauge field in a five-dimensional space-time. We adopt warping factors of the Randall-Sundrum type which are appropriate to regularize the hierarchy problem without imposing finite compactified extra dimensions. The existence and localization of gauge particles in the ordinary four-dimensional world is studied in detail on a thick brane derived out from the equations of motion of an action with a sine-Gordon potential contribution. Maxwell zero modes together with torsion effective fields are then obtained in a gravity-dilaton background inspired in close string theories. The dilaton plays a crucial role in order that the gauge field gets localized in a conformally invariant context. Kaluza-Klein massive states are also computed and, depending on certain parameters like dilaton coupling constant and asymptotic curvature, we are able to do it fully analytically. In a general approach we find that the solutions are of the Heun type. In some specific cases we can show that the Heun general solutions can be transformed into hypergeometric functions. In others, confluent Heun solutions can be transformed into simpler functions like Mathieu functions. Exact mass spectra are found in several cases. In others, we performed numerical calculations that show a well behaved phenomenology as well. In all the cases, Kaluza-Klein modes are strongly suppressed on the brane in the effective four-dimensional theory. (author)
Degenerate second order mean field games systems
Tonon, Daniela; Cardaliaguet, Pierre; Graber, Philip,; Poretta, Alessio
2014-01-01
Parallel session; International audience; We consider degenerate second order mean field games systems with a local coupling. The starting point is the idea that mean field games systems can be understood as an optimality condition for optimal control of PDEs. Developing this strategy for the degenerate second order case, we discuss the existence and uniqueness of a weak solution as well as its stability (vanishing viscosity limit). Speaker: Daniela TONON
The nature of apraxia in corticobasal degeneration.
Leiguarda, R; Lees, A J; Merello, M; STARKSTEIN, S; Marsden, C D
1994-01-01
Although apraxia is one of the most frequent signs in corticobasal degeneration, the phenomenology of this disorder has not been formally examined. Hence 10 patients with corticobasal degeneration were studied with a standardised evaluation for different types of apraxia. To minimise the confounding effects of the primary motor disorder, apraxia was assessed in the least affected limb. Whereas none of the patients showed buccofacial apraxia, seven showed deficits on tests of ideomotor apraxia...
Retinal Cell Degeneration in Animal Models
Masayuki Niwa; Hitomi Aoki; Akihiro Hirata; Hiroyuki Tomita; Green, Paul G.; Akira Hara
2016-01-01
The aim of this review is to provide an overview of various retinal cell degeneration models in animal induced by chemicals (N-methyl-d-aspartate- and CoCl2-induced), autoimmune (experimental autoimmune encephalomyelitis), mechanical stress (optic nerve crush-induced, light-induced) and ischemia (transient retinal ischemia-induced). The target regions, pathology and proposed mechanism of each model are described in a comparative fashion. Animal models of retinal cell degeneration provide insi...
2006-01-01
The author develops a deformation theory for degenerations of complex curves; specifically, he treats deformations which induce splittings of the singular fiber of a degeneration. He constructs a deformation of the degeneration in such a way that a subdivisor is "barked" (peeled) off from the singular fiber. These "barking deformations" are related to deformations of surface singularities (in particular, cyclic quotient singularities) as well as the mapping class groups of Riemann surfaces (complex curves) via monodromies. Important applications, such as the classification of atomic degenerations, are also explained.
Selective Attention to Perceptual Dimensions and Switching between Dimensions
Meiran, Nachshon; Dimov, Eduard; Ganel, Tzvi
2013-01-01
In the present experiments, the question being addressed was whether switching attention between perceptual dimensions and selective attention to dimensions are processes that compete over a common resource? Attention to perceptual dimensions is usually studied by requiring participants to ignore a never-relevant dimension. Selection failure…
Cultural dimensions and innovation
Directory of Open Access Journals (Sweden)
Anna Strychalska-Rudzewicz
2015-11-01
Full Text Available This paper examines the effect of culture’s dimensions on national innovation index. The results of Pearson correlation coefficient between culture dimensions and the Global Innovation Index (GII are very similar to the results obtained in the case of Summary Innovation Index (SII in European countries. The strong negative correlation was observed in the case of power distance and uncertainty avoidance whereas individualism has a positive effect on innovation index. The results suggest that low power distance and uncertainty-accepting countries may be more innovative than high power distance and uncertainty-avoiding societies.
DEFF Research Database (Denmark)
Wölfel, Christiane; Merritt, T.
2013-01-01
. The card-based tools are explained in terms of five design dimensions including the intended purpose and scope of use, duration of use, methodology, customization, and formal/material qualities. Our analysis suggests three design patterns or archetypes for existing card-based design method tools...
DEFF Research Database (Denmark)
Frederiksen, Morten
2012-01-01
in scope and mode influenced by the intersecting dimensions of relations, objects and situations. Furthermore, trust exists between an outer threshold of expected deceit and an inner threshold of confident reliance. The findings from the qualitative study contribute new knowledge on the diversity of trust...
Prospectives for gene therapy of retinal degenerations.
Thumann, Gabriele
2012-08-01
Retinal degenerations encompass a large number of diseases in which the retina and associated retinal pigment epithelial (RPE) cells progressively degenerate leading to severe visual disorders or blindness. Retinal degenerations can be divided into two groups, a group in which the defect has been linked to a specific gene and a second group that has a complex etiology that includes environmental and genetic influences. The first group encompasses a number of relatively rare diseases with the most prevalent being Retinitis pigmentosa that affects approximately 1 million individuals worldwide. Attempts have been made to correct the defective gene by transfecting the appropriate cells with the wild-type gene and while these attempts have been successful in animal models, human gene therapy for these inherited retinal degenerations has only begun recently and the results are promising. To the second group belong glaucoma, age-related macular degeneration (AMD) and diabetic retinopathy (DR). These retinal degenerations have a genetic component since they occur more often in families with affected probands but they are also linked to environmental factors, specifically elevated intraocular pressure, age and high blood sugar levels respectively. The economic and medical impact of these three diseases can be assessed by the number of individuals affected; AMD affects over 30 million, DR over 40 million and glaucoma over 65 million individuals worldwide. The basic defect in these diseases appears to be the relative lack of a neurogenic environment; the neovascularization that often accompanies these diseases has suggested that a decrease in pigment epithelium-derived factor (PEDF), at least in part, may be responsible for the neurodegeneration since PEDF is not only an effective neurogenic and neuroprotective agent but also a potent inhibitor of neovascularization. In the last few years inhibitors of vascularization, especially antibodies against vascular endothelial cell
Gang, Zhou
2008-01-01
Nonlinear Schrodinger / Gross-Pitaevskii equations play a central role in the understanding of nonlinear optical and macroscopic quantum systems. The large time dynamics of such systems is governed by interactions of the nonlinear ground state manifold, discrete neutral modes (``excited states'') and dispersive radiation. Systems with symmetry, in spatial dimensions larger than one, typically have degenerate neutral modes. Thus, we study the large time dynamics of systems with degenerate neutral modes. This requires a new normal form (nonlinear matrix Fermi Golden Rule) governing the system's large time asymptotic relaxation to the ground state (soliton) manifold.
On linear degeneracy of integrable quasilinear systems in higher dimensions
Ferapontov, E V; Klein, C
2010-01-01
We investigate $(d+1)$-dimensional quasilinear systems which are integrable by the method of hydrodynamic reductions. In the case $d\\geq 3$ we formulate a conjecture that any such system with an irreducible dispersion relation must be linearly degenerate. We prove this conjecture in the 2-component case, providing a complete classification of multi-dimensional integrable systems in question. In particular, our results imply the non-existence of 2-component integrable systems of hydrodynamic type for $d\\geq 6$. In the second half of the paper we discuss a numerical and analytical evidence for the impossibility of the breakdown of smooth initial data for linearly degenerate systems in 2+1 dimensions.
Optic pathway degeneration in Japanese black cattle.
Chiba, Shiori; Funato, Shingo; Horiuchi, Noriyuki; Matsumoto, Kotaro; Inokuma, Hisashi; Furuoka, Hidefumi; Kobayashi, Yoshiyasu
2015-02-01
Degeneration of the optic pathway has been reported in various animal species including cattle. We experienced a case of bilateral optic tract degeneration characterized by severe gliosis in a Japanese black cattle without any obvious visual defects. To evaluate the significance, pathological nature and pathogenesis of the lesions, we examined the optic pathway in 60 cattle (41 Japanese black, 13 Holstein and 6 crossbreed) with or without ocular abnormalities. None of these animals had optic canal stenosis. Degenerative changes with severe gliosis in the optic pathway, which includes the optic nerve, optic chiasm and optic tract, were only observed in 8 Japanese black cattle with or without ocular abnormalities. Furthermore, strong immunoreactivity of glial fibrillary acidic protein was observed in the retinal stratum opticum and ganglion cell layer in all 5 cattle in which the optic pathway lesions could be examined. As etiological research, we also examined whether the concentrations of vitamin A and vitamin B12 or bovine viral diarrhea virus (BVDV) infection was associated with optic pathway degeneration. However, our results suggested that the observed optic pathway degeneration was probably not caused by these factors. These facts indicate the presence of optic pathway degeneration characterized by severe gliosis that has never been reported in cattle without bilateral compressive lesions in the optic pathway or bilateral severe retinal atrophy.
The cell stress machinery and retinal degeneration.
Athanasiou, Dimitra; Aguilà, Monica; Bevilacqua, Dalila; Novoselov, Sergey S; Parfitt, David A; Cheetham, Michael E
2013-06-27
Retinal degenerations are a group of clinically and genetically heterogeneous disorders characterised by progressive loss of vision due to neurodegeneration. The retina is a highly specialised tissue with a unique architecture and maintaining homeostasis in all the different retinal cell types is crucial for healthy vision. The retina can be exposed to a variety of environmental insults and stress, including light-induced damage, oxidative stress and inherited mutations that can lead to protein misfolding. Within retinal cells there are different mechanisms to cope with disturbances in proteostasis, such as the heat shock response, the unfolded protein response and autophagy. In this review, we discuss the multiple responses of the retina to different types of stress involved in retinal degenerations, such as retinitis pigmentosa, age-related macular degeneration and glaucoma. Understanding the mechanisms that maintain and re-establish proteostasis in the retina is important for developing new therapeutic approaches to fight blindness.
Families and degenerations of conformal field theories
Energy Technology Data Exchange (ETDEWEB)
Roggenkamp, D.
2004-09-01
In this work, moduli spaces of conformal field theories are investigated. In the first part, moduli spaces corresponding to current-current deformation of conformal field theories are constructed explicitly. For WZW models, they are described in detail, and sigma model realizations of the deformed WZW models are presented. The second part is devoted to the study of boundaries of moduli spaces of conformal field theories. For this purpose a notion of convergence of families of conformal field theories is introduced, which admits certain degenerated conformal field theories to occur as limits. To such a degeneration of conformal field theories, a degeneration of metric spaces together with additional geometric structures can be associated, which give rise to a geometric interpretation. Boundaries of moduli spaces of toroidal conformal field theories, orbifolds thereof and WZW models are analyzed. Furthermore, also the limit of the discrete family of Virasoro minimal models is investigated. (orig.)
Kaluza theory with zero-length extra dimensions
Stoica, Ovidiu Cristinel
2016-01-01
A new approach to the Kaluza theory and its relation to the gauge theory is presented. Two degenerate metrics on the $4+d$-dimensional total manifold are used, one corresponding to the spacetime metric and giving the fiber of the gauge bundle, and the other one to the metric of the fiber and giving the horizontal bundle of the connection. When combined, the two metrics give the Kaluza metric and its generalization to the non-abelian case, justifying thus his choice. Considering the two metrics as fundamental rather than the Kaluza metric explains why Kaluza's theory should not be regarded as five-dimensional vacuum gravity. This approach suggests that the only evidence of extra dimensions is given by the existence of the gauge forces, explaining thus why other kinds of evidence are not available. In addition, because the degenerate metric corresponding to the spacetime metric vanishes along the extra dimensions, the lengths in the extra dimensions is zero, preventing us to directly probe them. Therefore this ...
Cultural dimensions of learning
Eyford, Glen A.
1990-06-01
How, what, when and where we learn is frequently discussed, as are content versus process, or right brain versus left brain learning. What is usually missing is the cultural dimension. This is not an easy concept to define, but various aspects can be identified. The World Decade for Cultural Development emphasizes the need for a counterbalance to a quantitative, economic approach. In the last century poets also warned against brutalizing materialism, and Sorokin and others have described culture more recently in terms of cohesive basic values expressed through aesthetics and institutions. Bloom's taxonomy incorporates the category of affective learning, which internalizes values. If cultural learning goes beyond knowledge acquisition, perhaps the surest way of understanding the cultural dimension of learning is to examine the aesthetic experience. This can use myths, metaphors and symbols, and to teach and learn by using these can help to unlock the human potential for vision and creativity.
Quantum Gravity signatures in the Unruh effect
Alkofer, Natalia; Saueressig, Frank; Versteegen, Fleur
2016-01-01
We study quantum gravity signatures emerging from phenomenologically motivated multiscale models, spectral actions, and Causal Set Theory within the detector approach to the Unruh effect. We show that while the Unruh temperature is unaffected, Lorentz-invariant corrections to the two-point function leave a characteristic fingerprint in the induced emission rate of the accelerated detector. Generically, quantum gravity models exhibiting dynamical dimensional reduction exhibit a suppression of the Unruh rate at high energy while the rate is enhanced in Kaluza-Klein theories with compact extra dimensions. We quantify this behavior by introducing the "Unruh dimension" as the effective spacetime dimension seen by the Unruh effect and show that it is related, though not identical, to the spectral dimension used to characterize spacetime in quantum gravity. We comment on the physical origins of these effects and their relevance for black hole evaporation.
Quantum gravity signatures in the Unruh effect
Alkofer, Natalia; D'Odorico, Giulio; Saueressig, Frank; Versteegen, Fleur
2016-11-01
We study quantum gravity signatures emerging from phenomenologically motivated multiscale models, spectral actions, and causal set theory within the detector approach to the Unruh effect. We show that while the Unruh temperature is unaffected, Lorentz-invariant corrections to the two-point function leave a characteristic fingerprint in the induced emission rate of the accelerated detector. Generically, quantum gravity models exhibiting dynamical dimensional reduction exhibit a suppression of the Unruh rate at high energy while the rate is enhanced in Kaluza-Klein theories with compact extra dimensions. We quantify this behavior by introducing the "Unruh dimension" as the effective spacetime dimension seen by the Unruh effect and show that it is related, though not identical, to the spectral dimension used to characterize spacetime in quantum gravity. We comment on the physical origins of these effects and their relevance for black hole evaporation.
Introduction to Extra Dimensions
Energy Technology Data Exchange (ETDEWEB)
Rizzo, Thomas G.; /SLAC
2010-04-29
Extra dimensions provide a very useful tool in addressing a number of the fundamental problems faced by the Standard Model. The following provides a very basic introduction to this very broad subject area as given at the VIII School of the Gravitational and Mathematical Physics Division of the Mexican Physical Society in December 2009. Some prospects for extra dimensional searches at the 7 TeV LHC with {approx}1 fb{sup -1} of integrated luminosity are provided.
DEFF Research Database (Denmark)
Eskjær, Mikkel Fugl
2013-01-01
is largely dependent on regional media systems, yet the role this regional dimension plays has been largely overlooked. This article presents a comparative study of climate-change coverage in three geo-cultural regions, The Middle East, Scandinavia, and North America, and explores the link between global...... climate-change communication and regional media systems. It finds that regional variations in climate-change communication carry important communicative implications concerning perceptions of climate change's relevance and urgency...
[New aspects in age related macular degeneration].
Turlea, C
2012-01-01
Being the leading cause of blindness in modern world Age Related Macular Degeneration has beneficiated in the last decade of important progress in diagnosis, classification and the discovery of diverse factors who contribute to the etiology of this disease. Treatments have arised who can postpone the irreversible evolution of the disease and thus preserve vision. Recent findings have identified predisposing genetic factors and also inflamatory and imunological parameters that can be modified trough a good and adequate prevention and therapy This articole reviews new aspects of patology of Age Related Macular Degeneration like the role of complement in maintaining inflamation and the role of oxidative stress on different structures of the retina.
Intracavity frequency-doubled degenerate laser
Liew, Seng Fatt; Weiler, Sascha; Monjardin-Lopez, Jesus Fernando; Ramme, Mark; Redding, Brandon; Choma, Michael A; Cao, Hui
2016-01-01
We develop a green light source with low spatial coherence via intracavity frequency doubling of a solid-state degenerate laser. The second harmonic emission supports many more transverse modes than the fundamental emission, and exhibit lower spatial coherence. A strong suppression of speckle formation is demonstrated for both fundamental and second harmonic beams. Using the green emission for fluorescence excitation, we show the coherent artifacts are removed from the full-field fluorescence images. The high power, low spatial coherence and good directionality makes the green degenerate laser an attractive illumination source for parallel imaging and projection display.
Angels and Degenerates: Artistic Virtuosity and Degeneration Theory in Fin de Siècle Fiction
2015-01-01
The aim in "Angels and Degenerates: Artistic Virtuosity and Degeneration Theory in Fin de Siècle Fiction" is to complicate the popular image of the fin de siècle as uniformly pessimistic by examining the continuities between a range of novelists, as well as other late nineteenth century writers from such disparate fields as psychology and cultural criticism, as they critique degeneration theory. Some of these writers, like Thomas Hardy, H.G. Wells, and Sarah Grand, are typically read as promo...
Inert scalar dark matter in an extra dimension inspired model
Energy Technology Data Exchange (ETDEWEB)
Lineros, R.A.; Santos, F.A. Pereira dos, E-mail: rlineros@ific.uv.es, E-mail: fabio.alex@fis.puc-rio.br [Instituto de Física Corpuscular – CSIC/U. Valencia, Parc Científic, calle Catedrático José Beltrán 2, E-46980 Paterna (Spain)
2014-10-01
In this paper we analyze a dark matter model inspired by theories with extra dimensions. The dark matter candidate corresponds to the first Kaluza–Klein mode of an real scalar added to the Standard Model. The tower of new particles enriches the calculation of the relic abundance. For large mass splitting, the model converges to the predictions of the inert singlet dark matter model. For nearly degenerate mass spectrum, coannihilations increase the cross-sections used for direct and indirect dark matter searches. Moreover, the Kaluza–Klein zero mode can mix with the SM higgs and further constraints can be applied.
Motor axon excitability during Wallerian degeneration
DEFF Research Database (Denmark)
Moldovan, Mihai; Alvarez, Susana; Krarup, Christian
2008-01-01
, action potential propagation and structural integrity of the distal segment are maintained. The aim of this study was to investigate in vivo the changes in membrane function of motor axons during the 'latent' phase of Wallerian degeneration. Multiple indices of axonal excitability of the tibial nerve...
MR findings of degenerating parenchymal neurocysticercosis
Energy Technology Data Exchange (ETDEWEB)
Lee, Yul; Chung, Eun A; Yang, Ik; Park, Hae Jung; Chung, Soo Young [Hallym Univ. Kangnam Sungshim Hospital, Seoul (Korea, Republic of)
1996-06-01
To evaluate MR imaging findings of degenerating parenchymal neurocysticercosis and to determine the characteristics which distinguish it from other brain diseases. MR imagings of 19 patients (56 lesions) of degenerating parenchymal neurocysticercosis were retrospectively evaluated, focusing on the size and location of lesions signal intensity patterns of cyst fluid and wall, the extent of the surrounding edema and features of contrast enhancement. Degenerating parenchymal neurocysticercosis was located in gray or subcortical while matter in 89.3% of 56 lesions (50/56) ; most of these (98.2%) were smaller than 2 cm in diameter. Cyst fluid signal was hyperintense relative to CSF on T1 and proton density weighted images (92.9%). A hypointense signal rim of the cyst wall was noted in the lesions on proton density (92.9%) and T2 weighted (98.2%) images, Surrounding edema was mostly mild. Peripheral rim enhancement was noted in all lesions, and this was frequently irregular and lobulated (67.9%) with a focal defect in the enhancing rim(41.1%). Findings which could be helpful in distinguishing degenerating parencymal neurocysticercosis from other brain diseases are as follows : small, superficial lesions ; hyperintense signal of the cyst fluid on T1 and proton density weighted images ; hypointense signal of the cyst wall on proton density and T2 weighted images ; relatively mild extent of surrounding edema, and peripheral rim enhancement which is frequently irregular and lobulated with a focal defect in the enhancing rim.
Single Degenerate Progenitors of Type Ia Supernovae
Bours, Madelon; Toonen, Silvia; Nelemans, Gijs
2013-01-01
There is a general agreement that Type Ia supernovae correspond to the thermonuclear runaway of a white dwarf (WD) in a compact binary. The details of these progenitor systems are still unclear. Using the population synthesis code SeBa and several assumption for the WD retention efficiency, we estimate the delay times and supernova rates for the single degenerate scenario.
Driving and Age-Related Macular Degeneration
Owsley, Cynthia; McGwin, Gerald, Jr.
2008-01-01
This article reviews the research literature on driving and age-related macular degeneration, which is motivated by the link between driving and the quality of life of older adults and their increased collision rate. It addresses the risk of crashes, driving performance, driving difficulty, self-regulation, and interventions to enhance, safety,…
The nature of apraxia in corticobasal degeneration.
Leiguarda, R; Lees, A J; Merello, M; Starkstein, S; Marsden, C D
1994-01-01
Although apraxia is one of the most frequent signs in corticobasal degeneration, the phenomenology of this disorder has not been formally examined. Hence 10 patients with corticobasal degeneration were studied with a standardised evaluation for different types of apraxia. To minimise the confounding effects of the primary motor disorder, apraxia was assessed in the least affected limb. Whereas none of the patients showed buccofacial apraxia, seven showed deficits on tests of ideomotor apraxia and movement imitation, four on tests of sequential arm movements (all of whom had ideomotor apraxia), and three on tests of ideational apraxia (all of whom had ideomotor apraxia). Ideomotor apraxia significantly correlated with deficit in both the mini mental state examination and in a task sensitive to frontal lobe dysfunction (picture arrangement). Two of the three patients with ideomotor apraxia and ideational apraxia showed severe cognitive impairments. The alien limb behaviour was present only in patients with ideomotor apraxia. In conclusion, ideomotor apraxia is the most frequent type of apraxia in corticobasal degeneration, and may be due to dysfunction of the supplementary motor area. There is a subgroup of patients with corticobasal degeneration who have a severe apraxia (ideomotor and ideational apraxia), which correlates with global cognitive impairment, and may result from additional parietal or diffuse cortical damage. PMID:8163995
Specific heats of degenerate ideal gases
Caruso, Francisco; Oguri, Vitor; Silveira, Felipe
2017-01-01
From arguments based on Heisenberg's uncertainty principle and Pauli's exclusion principle, the molar specific heats of degenerate ideal gases at low temperatures are estimated, giving rise to values consistent with the Nerst-Planck Principle (third law of Thermodynamics). The Bose-Einstein condensation phenomenon based on the behavior of specific heat of massive and non-relativistic boson gases is also presented.
Transversal heteroclinic orbits in general degenerate cases
Institute of Scientific and Technical Information of China (English)
朱德明
1996-01-01
A geometrical method using the exponential dichotomy and the invariant manifold thoery is given to set up the criteria for the existence of transversal and tangential heterodinic orbits under the most general degenerate cases. Conclusions given here extend and contain the relevant known results.
Depression in Age-Related Macular Degeneration
Casten, Robin; Rovner, Barry
2008-01-01
Age-related macular degeneration (AMD) is a major cause of disability in the elderly, substantially degrades the quality of their lives, and is a risk factor for depression. Rates of depression in AMD are substantially greater than those found in the general population of older people, and are on par with those of other chronic and disabling…
DNA sequencing by synthesis with degenerate primers
Institute of Scientific and Technical Information of China (English)
2008-01-01
The degenerate primer-based sequencing Was developed by a synthesis method(DP-SBS)for high-throughput DNA sequencing,in which a set of degenerate primers are hybridized on the arrayed DNA templates and extended by DNA polymerase on microarrays.In this method,adifferent set of degenerate primers containing a give nnumber(n)of degenerate nucleotides at the 3'-ends were annealed to the sequenced templates that were immobilized on the solid surface.The nucleotides(n+1)on the template sequences were determined by detecting the incorporation of fluorescent labeled nucleotides.The fluorescent labeled nucleotide was incorporated into the primer in a base-specific manner after the enzymatic primer extension reactions and nine-base length were read out accurately.The main advanmge of the DP-SBS is that the method only uses very conventional biochemical reagents and avoids the complicated special chemical reagents for removing the labeled nucleotides and reactivating the primer for further extension.From the present study,it is found that the DP-SBS method is reliable,simple,and cost-effective for laboratory-sequencing a large amount of short DNA fragments.
DEFF Research Database (Denmark)
Andersen, lotte bøgh; Beck Jørgensen, Torben; Kjeldsen, Anne-Mette
2012-01-01
Further integration of the public value literature with other strands of literature within Public Administration necessitates a more specific classification of public values. This paper applies a typology linked to organizational design principles, because this is useful for empirical public...... administration studies. Based on an existing typology of modes of governance, we develop a classification and test it empirically, using survey data from a study of the values of 501 public managers. We distinguish between seven value dimensions (the public at large, rule abidance, societal interests, budget...... the integration between the public value literature and other parts of the Public Administration discipline....
On Doubly Degenerate Quasilinear Parabolic Equations of Higher Order
Institute of Scientific and Technical Information of China (English)
Zhen Hai LIU
2005-01-01
We deal with the existence of periodic solutions for doubly degenerate quasilinear parabolic equations of higher order, which can degenerate, on a part of the boundary, on a segment in the interior of the domain and in time.
Quasiconformal mappings and degenerate elliptic and parabolic equations
Directory of Open Access Journals (Sweden)
Filippo Chiarenza
1987-11-01
Full Text Available In this paper two Harnak inequalities are proved concerning a degenerate elliptic and a degenerate parabolic equation. In both cases the weight giving the degeneracy is a power of the jacobian of a quasiconformal mapping.
Degenerate solutions obtained from several variants of factor analysis
Zijlstra, Bonne J.H.; Kiers, Henk A.L.
2002-01-01
Considerable research has been performed concerning degenerate solutions from the Parafac model. However, degenerate solutions have also been reported to occur with the shifted multiplicative model and a model for component analysis of multitrait multimethod matrices. Furthermore, we obtained
Adjoint Functors and Representation Dimensions
Institute of Scientific and Technical Information of China (English)
Chang Chang XI
2006-01-01
We study the global dimensions of the coherent functors over two categories that are linked by a pair of adjoint functors. This idea is then exploited to compare the representation dimensions of two algebras. In particular, we show that if an Artin algebra is switched from the other, then they have the same representation dimension.
Generalised Eisenhart lift of the Toda chain
Energy Technology Data Exchange (ETDEWEB)
Cariglia, Marco, E-mail: marco@iceb.ufop.br [DEFIS, Universidade Federal de Ouro Preto, Campus Morro do Cruzeiro, 35400-000 Ouro Preto, MG (Brazil); Gibbons, Gary, E-mail: g.w.gibbons@damtp.cam.ac.uk [DAMTP, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA (United Kingdom)
2014-02-15
The Toda chain of nearest neighbour interacting particles on a line can be described both in terms of geodesic motion on a manifold with one extra dimension, the Eisenhart lift, or in terms of geodesic motion in a symmetric space with several extra dimensions. We examine the relationship between these two realisations and discover that the symmetric space is a generalised, multi-particle Eisenhart lift of the original problem that reduces to the standard Eisenhart lift. Such generalised Eisenhart lift acts as an inverse Kaluza-Klein reduction, promoting coupling constants to momenta in higher dimension. In particular, isometries of the generalised lift metric correspond to energy preserving transformations that mix coordinates and coupling constants. A by-product of the analysis is that the lift of the Toda Lax pair can be used to construct higher rank Killing tensors for both the standard and generalised lift metrics.
Generalised Eisenhart lift of the Toda chain
Cariglia, Marco
2013-01-01
The Toda chain of nearest neighbour interacting particles on a line can be described both in terms of geodesic motion on a manifold with one extra dimension, the Eisenhart lift, or in terms of geodesic motion in a symmetric space with several extra dimensions. We examine the relationship between these two realisations and discover that the symmetric space is a generalised, multi-particle Eisenhart lift of the original problem, that reduces to the standard Eisenhart lift. Such generalised Eisenhart lift acts as an inverse Kaluza-Klein reduction, promoting coupling constants to momenta in higher dimension. In particular, isometries of the generalised lift metric correspond to energy preserving transformations that mix coordinates and coupling constants. A by-product of the analysis is that the lift of the Toda Lax pair can be used to construct higher rank Killing tensors for both the standard and generalised lift metrics.
Examples of naked singularity formation in higher-dimensional Einstein-vacuum spacetimes
An, Xinliang; Lü, H
2015-01-01
The vacuum Einstein equations in 5+1 dimensions are shown to admit solutions describing naked singularity formation in gravitational collapse from nonsingular asymptotically locally flat initial data. We present a class of specific examples with spherical extra dimensions. Thanks to the Kaluza-Klein dimensional reduction, these spacetimes are constructed by lifting continuously self-similar solutions of the 4-dimensional Einstein-scalar field system with a negative exponential potential. Their existence provides a new test-bed for weak cosmic censorship in higher-dimensional gravity. In addition, we point out why a similar attempt of embedding Christodoulou's well-known solutions for massless scalar fields fails to capture formation of naked singularities in 4+1 dimensions.
Simple 5D SO(10) GUT and sparticle masses
Fukuyama, Takeshi; Okada, Nobuchika
2008-12-01
Simple supersymmetric SO(10) grand unified theory in five dimensions is proposed, in which the fifth dimension is compactified on the S1/(Z2×Z2') orbifold with two inequivalent branes at the orbifold fixed points. In this model, all matter and Higgs multiplets reside on one brane (PS brane) where the Pati-Salam (PS) symmetry is manifest, while only the SO(10) gauge multiplet resides on the bulk. The supersymmetry breaking on the other brane [SO(10) brane] is transmitted to the PS brane through the gaugino mediation with the bulk gauge multiplet. We examine sparticle mass spectrum in this setup and show that the neutralino LSP as the dark matter candidate can be realized when the compactification scale of the fifth dimension is higher than the PS symmetry breaking scale, keeping the successful gauge coupling unification after incorporating threshold corrections of Kaluza-Klein modes of the bulk gauge multiplets.
Borromean ground state of fermions in two dimensions
Volosniev, A. G.; Fedorov, D. V.; Jensen, A. S.; Zinner, N. T.
2014-09-01
The study of quantum mechanical bound states is as old as quantum theory itself. Yet, it took many years to realize that three-body Borromean systems that are bound when any two-body subsystem is unbound are abundant in nature. Here we demonstrate the existence of Borromean systems of spin-polarized (spinless) identical fermions in two spatial dimensions. The ground state with zero orbital (planar) angular momentum exists in a Borromean window between critical two- and three-body strengths. The doubly degenerate first excited states of angular momentum one appears only very close to the two-body threshold. They are the lowest in a possible sequence of so-called super-Efimov states. While the observation of the super-Efimov scaling could be very difficult, the Borromean ground state should be observable in cold atomic gases and could be the basis for producing a quantum gas of three-body states in two dimensions.
Urban Screen and Spatial Dimension
Directory of Open Access Journals (Sweden)
Litta Primasari
2013-11-01
Full Text Available This paper is discussing about the urban screen phenomena and its influence to spatial dimension in urban space. The visual characteristics which are forming a spatial dimension will be an emphasis to be presented. Urban screen as a visual intervention has an impact to spatial configuration in urban space. The space dimension was not dominated with materiality limitation, but also images. We have to consider that people senses can measure a spatial dimension, knowing as a perception. That is a human visual and mind relation. The spatial dimension has no longer tangible boundary, but also has intangible ones. Spatial dimension in urban screens phenomena is not merely mathematics, nor spatial dimension in physics which are based on a three-dimensional Cartesian coordinate system. Movement can be expressed in other terms, by how far we can move depends on our eyes to catch that space limitation, and how fast we can move is depends on our mind to perceive some visual phenomenon, that is a spatial dimension. So, the dimension will depend on a visual quality that we perceived. The movement of the body and people’s thought will be an important term to generate the space dimension in urban screen phenomenon. The activity of body’s movement and thought will influence the depth of space dimension.
Correlation dimension of financial market
Nie, Chun-Xiao
2017-05-01
In this paper, correlation dimension is applied to financial data analysis. We calculate the correlation dimensions of some real market data and find that the dimensions are significantly smaller than those of the simulation data based on geometric Brownian motion. Based on the analysis of the Chinese and US stock market data, the main results are as follows. First, by calculating three data sets for the Chinese and US market, we find that large market volatility leads to a significant decrease in the dimensions. Second, based on 5-min stock price data, we find that the Chinese market dimension is significantly larger than the US market; this shows a significant difference between the two markets for high frequency data. Third, we randomly extract stocks from a stock set and calculate the correlation dimensions, and find that the average value of these dimensions is close to the dimension of the original set. In addition, we analyse the intuitional meaning of the relevant dimensions used in this paper, which are directly related to the average degree of the financial threshold network. The dimension measures the speed of the average degree that varies with the threshold value. A smaller dimension means that the rate of change is slower.
Jackson, David J
2016-01-01
A physical theory of the world is presented under the unifying principle that all of nature is laid out before us and experienced through the passage of time. The one-dimensional progression in time is opened out into a multi-dimensional mathematically consistent flow, with the simplicity of the former giving rise to symmetries of the latter. The act of perception identifies an extended spacetime arena of intermediate dimension, incorporating the symmetry of geometric spatial rotations, against which physical objects are formed and observed. The spacetime symmetry is contained as a subgroup of, and provides a natural breaking mechanism for, the higher general symmetry of time. It will be described how the world of gravitation and cosmology, as well as quantum theory and particle physics, arises from these considerations.
DEFF Research Database (Denmark)
Wölfel, Christiane; Merritt, T.
2013-01-01
. The card-based tools are explained in terms of five design dimensions including the intended purpose and scope of use, duration of use, methodology, customization, and formal/material qualities. Our analysis suggests three design patterns or archetypes for existing card-based design method tools...... and highlights unexplored areas in the design space. The paper concludes with recommendations for the future development of card-based methods for the field of interaction design.......There are many examples of cards used to assist or provide structure to the design process, yet there has not been a thorough articulation of the strengths and weaknesses of the various examples. We review eighteen card-based design tools in order to understand how they might benefit designers...
Schweitzer, Eugen
2009-01-01
In different passages of his dialogues, Plato showed deep mathematically-based physical insights. Regrettably most readers overlooked the respective statements, or they utterly did not understand those hints since they were full of philological fallacious terms. Respectable translators misinterpreted such statements and therefore Plato's respective remarks were not recognized as substantial knowledge. Furthermore, Plato often supplemented such basic remarks by diffusely veiled and varied allusions that were often ironically hidden somewhere in his dialogues by inconspicuous double meanings. However, this mode of intentionally coded discrete communication was generally not understood because such irony is not to everyone's taste. However, the attempts to reconstruct Plato's system on the basis of admittedly individually interpreted double meanings lead to a conclusive mathematical-physical cyclical system of dimensions. Additionally it was possible to assign Plato's system of philosophical ideas analogously to...
Phenomenology of Extra Dimensions
Energy Technology Data Exchange (ETDEWEB)
Hewett, J.L.; /SLAC
2006-11-07
If the structure of spacetime is different than that readily observed, gravitational physics, particle physics and cosmology are all immediately affected. The physics of extra dimensions offers new insights and solutions to fundamental questions arising in these fields. Novel ideas and frameworks are continuously born and evolved. They make use of string theoretical features and tools and they may reveal if and how the 11-dimensional string theory is relevant to our four-dimensional world. We have outlined some of the experimental observations in particle and gravitational physics as well as astrophysical and cosmological considerations that can constrain or confirm these scenarios. These developing ideas and the wide interdisciplinary experimental program that is charted out to investigate them mark a renewed effort to describe the dynamics behind spacetime. We look forward to the discovery of a higher dimensional spacetime.
Lévay, Péter
2011-01-01
We link the recently discovered black hole-qubit correspondence to the structure of extra dimensions. In particular we show that for toroidal compactifications of type IIB string theory simple qubit systems arise naturally from the geometrical data of the tori parametrized by the moduli. We also generalize the recently suggested idea of the attractor mechanism as a distillation procedure of GHZ-like entangled states on the event horizon, to moduli stabilization for flux attractors in F-theory compactifications on elliptically fibered Calabi-Yau four-folds. Finally using a simple example we show that the natural arena for qubits to show up is an embedded one within the realm of fermionic entanglement of quantum systems with indistinguishable constituents.
Supersymmetry in 6d Dirac Action
Fujimoto, Yukihiro; Nishiwaki, Kenji; Sakamoto, Makoto; Tatsumi, Kentaro
2016-01-01
We investigate a 6d Dirac fermion on a rectangle. It is found that the 4d spectrum is governed by $N = 2$ supersymmetric quantum mechanics. Then we demonstrate that the supersymmetry is very useful to classify all allowed boundary conditions and to expand the 6d Dirac field in Kaluza-Klein modes. A striking feature of the model is that even though the 6d Dirac fermion has non-vanishing bulk mass, the 4d mass spectrum can contain degenerate massless chiral fermions, which may provide a hint to solve the generation problem of the quarks and leptons. It is pointed out that zero energy solutions are not affected by the presence of the boundaries, while the boundary conditions work well for determining the positive energy solutions.
State-space Manifold and Rotating Black Holes
Bellucci, Stefano
2010-01-01
We study a class of fluctuating higher dimensional black hole configurations obtained in string theory/ $M$-theory compactifications. We explore the intrinsic Riemannian geometric nature of Gaussian fluctuations arising from the Hessian of the coarse graining entropy, defined over an ensemble of brane microstates. It has been shown that the state-space geometry spanned by the set of invariant parameters is non-degenerate, regular and has a negative scalar curvature for the rotating Myers-Perry black holes, Kaluza-Klein black holes, supersymmetric $AdS_5$ black holes, $D_1$-$D_5$ configurations and the associated BMPV black holes. Interestingly, these solutions demonstrate that the principal components of the state-space metric tensor admit a positive definite form, while the off diagonal components do not. Furthermore, the ratio of diagonal components weakens relatively faster than the off diagonal components, and thus they swiftly come into an equilibrium statistical configuration. Novel aspects of the scali...
Ultracompact quantum splitter of degenerate photon pairs
He, Jiakun; Casas-Bedoya, Alvaro; Zhang, Yanbing; Xiong, Chunle; Eggleton, Benjamin J
2015-01-01
Integrated sources of indistinguishable photons have attracted a lot of attention because of their applications in quantum communication and optical quantum computing. Here, we demonstrate an ultra-compact quantum splitter for degenerate single photons based on a monolithic chip incorporating Sagnac loop and a micro-ring resonator with a footprint of 0.011 mm2, generating and deterministically splitting indistinguishable photon pairs using time-reversed Hong-Ou-Mandel interference. The ring resonator provides enhanced photon generation rate, and the Sagnac loop ensures the photons travel through equal path lengths and interfere with the correct phase to enable the reversed HOM effect to take place. In the experiment, we observed a HOM dip visibility of 94.5 +- 3.3 %, indicating the photons generated by the degenerate single photon source are in a suitable state for further integration with other components for quantum applications, such as controlled-NOT gates.
Acquired hepatocerebral degeneration: A case report
Institute of Scientific and Technical Information of China (English)
Wei-Xing Chen; Ping Wang; Sen-Xiang Yan; You-Ming Li; Chao-Hui Yu; Ling-Ling Jiang
2005-01-01
AIM: Acquired hepatocerebral degeneration (AHD) is an exceptional type of hepatic encephalopathies (HE). It is characterized by neuropsychiatric and extrapyramidal symptomathology similar to that seen in hepatolenticular degeneration (Wilson's disease). In this paper, we report a case of AHD with unusual presenting features.METHODS: A 28-year-old man with AHD was described and the literature was reviewed.RESULTS: The man had a history of HBV-related liver cirrhosis. He was admitted to our hospital with apathy,dysarthria, mild consciousness impairment and extrapyramidal symptoms after hematemesis. By review of the literature,cases with AHD often did not present consciousness impairment. So our case was once diagnosed incorrectly as Wilson's disease.CONCLUSION: AHD is a rare syndrome and its variable clinical manifestations make it difficult to be diagnosed.But we believe that extensive examination and thorough understanding of the disease are beneficial to a correct diagnosis. Moreover, biocoene is effective in treating the case.
Impact of warped extra dimensions on the dipole coefficients in b → sγ transitions
Malm, Raoul; Neubert, Matthias; Schmell, Christoph
2016-04-01
We calculate the electro- and chromomagnetic dipole coefficients C 7 γ,8 g and {tilde{C}}_{7γ, 8g} in the context of the minimal Randall-Sundrum (RS) model with a Higgs sector localized on the IR brane using the five-dimensional (5D) approach, where the coefficients are expressed in terms of integrals over 5D propagators. Since we keep the full dependence on the Yukawa matrices, the integral expressions are formally valid to all orders in v 2/ M KK 2 . In addition we relate our results to the expressions obtained in the Kaluza-Klein (KK) decomposed theory and show the consistency in both pictures analytically and numerically, which presents a non-trivial cross-check. In Feynman-'t Hooft gauge, the dominant corrections from virtual KK modes arise from the scalar parts of the W ±-boson penguin diagrams, including the contributions from the scalar component of the 5D gauge-boson field and from the charged Goldstone bosons in the Higgs sector. The size of the KK corrections depends on the parameter y *, which sets the upper bound for the anarchic 5D Yukawa matrices. We find that for y * ≳ 1 the KK corrections are proportional to y ∗ 2 . We discuss the phenomenological implications of our results for the branching ratio Br(overline{B}to {X}_sγ ) , the time-dependent CP asymmetry S K ∗ γ , the direct CP asymmetry A CP b → sγ and the CP asymmetry difference Δ A CP b → sγ . We can derive a lower bound on the first KK gluon resonance of 3 .8 TeV for y * = 3, requiring that at least 10% of the RS parameter space covers the experimental 2 σ error margins. We further discuss the branching ratio Br(overline{B}to {X}_s{l}+{l}-) and compare our predictions for C 7γ,9,10 and {tilde{C}}_{7γ, 9,10} with phenomenological results derived from model-independent analyses.
Interactive Dimensioning of Parametric Models
Kelly, T.
2015-05-01
We propose a solution for the dimensioning of parametric and procedural models. Dimensioning has long been a staple of technical drawings, and we present the first solution for interactive dimensioning: A dimension line positioning system that adapts to the view direction, given behavioral properties. After proposing a set of design principles for interactive dimensioning, we describe our solution consisting of the following major components. First, we describe how an author can specify the desired interactive behavior of a dimension line. Second, we propose a novel algorithm to place dimension lines at interactive speeds. Third, we introduce multiple extensions, including chained dimension lines, controls for different parameter types (e.g. discrete choices, angles), and the use of dimension lines for interactive editing. Our results show the use of dimension lines in an interactive parametric modeling environment for architectural, botanical, and mechanical models. © 2015 The Author(s) Computer Graphics Forum © 2015 The Eurographics Association and John Wiley & Sons Ltd. Published by John Wiley & Sons Ltd.
Dichromatic Langmuir waves in degenerate quantum plasma
Dubinov, A. E.; Kitayev, I. N.
2015-06-01
Langmuir waves in fully degenerate quantum plasma are considered. It is shown that, in the linear approximation, Langmuir waves are always dichromatic. The low-frequency component of the waves corresponds to classical Langmuir waves, while the high-frequency component, to free-electron quantum oscillations. The nonlinear problem on the profile of dichromatic Langmuir waves is solved. Solutions in the form of a superposition of waves and in the form of beatings of its components are obtained.
Immunology of age related macular degeneration
Institute of Scientific and Technical Information of China (English)
Kijlstra Aize; Yang Peizeng
2011-01-01
@@ Age-related macular degeneration(AMD)is the most important cause of blindness in persons over 55 years of age in the Western world.In view of the increasing life expectancy we can assume that the problem will increase dramatically over the coming decades unless preventive or therapeutic measures are developed.Towards this goal many groups all over the world have performed epidemiological studies to identify potential risk factors for AMD.
Degenerate spacetimes in first order gravity
Kaul, Romesh K
2016-01-01
We present a systematic framework to obtain the most general solutions of the equations of motion in first order gravity theory with degenerate tetrads. There are many possible solutions. Generically, these exhibit non-vanishing torsion even in the absence of any matter coupling. These solutions are shown to contain a special set of eight configurations which are associated with the homogeneous model three-geometries of Thurston.
Degenerate RFID Channel Modeling for Positioning Applications
Directory of Open Access Journals (Sweden)
A. Povalac
2012-12-01
Full Text Available This paper introduces the theory of channel modeling for positioning applications in UHF RFID. It explains basic parameters for channel characterization from both the narrowband and wideband point of view. More details are given about ranging and direction finding. Finally, several positioning scenarios are analyzed with developed channel models. All the described models use a degenerate channel, i.e. combined signal propagation from the transmitter to the tag and from the tag to the receiver.
Biomechanical study of intervertebral disc degeneration
González Guitiérrez, Ramiro Arturo
2012-01-01
Degeneration and age affect the biomechanics of the intervertebral disc, by reducing its stiffness, flexibility and shock absorption capacities against daily movement and spinal load. The biomechanical characterization of intervertebral discs is achieved by conducting mechanical testing to vertebra-disc-vertebra segments and applying axial, shear, bend and torsion loads, statically or dynamically, with load magnitudes corresponding to the physiological range. However, traditional testing does...
Biomechanical study of intervertebral disc degeneration
González Guitiérrez, Ramiro Arturo
2012-01-01
Degeneration and age affect the biomechanics of the intervertebral disc, by reducing its stiffness, flexibility and shock absorption capacities against daily movement and spinal load. The biomechanical characterization of intervertebral discs is achieved by conducting mechanical testing to vertebra-disc-vertebra segments and applying axial, shear, bend and torsion loads, statically or dynamically, with load magnitudes corresponding to the physiological range. However, traditional testing does...
Depression in Age-Related Macular Degeneration
Casten,Robin; Rovner,Barry
2008-01-01
Age-related macular degeneration (AMD) is a major cause of disability in the elderly, substantially degrades the quality of their lives, and is a risk factor for depression. Rates of depression in AMD are substantially greater than those found in the general population of older people, and are on par with those of other chronic and disabling diseases. This article discusses the effect of depression on vision-related disability in patients with AMD, suggests methods for screening for depressio...
Stem cell horizons in intervertebral disc degeneration
Directory of Open Access Journals (Sweden)
Joseph Ciacci
2009-01-01
Full Text Available Joseph Ciacci1, Allen Ho1,2, Christopher P Ames3, Rahul Jandial41Division of Neurosurgery, University of California, San Diego, La Jolla, California, USA; 2Del E Webb Neurosciences, Aging and Stem Cell Research Center, The Burnham Institute for Medical Research, La Jolla, California, USA; 3Department of Neurological Surgery, University of California, San Francisco, San Francisco, CA, USA; 4Division of Neurosurgery, Department of Surgery, City of Hope Cancer Center, Duarte, CA, USAAbstract: Intervertebral disc degeneration remains a pervasive and intractable disease arising from a combination of aging and stress on the back and spine. The growing field of regenerative medicine brings the promise of stem cells in the treatment of disc disease. Scientists and physicians hope to employ stem cells not only to stop, but also reverse degeneration. However, there are many important outstanding issues, including the hostile avascular, apoptotic physiological environment of the intervertebral disc, and the difficulty of obtaining mesenchymal stem cells, and directing them towards chondrocytic differentiation and integration within the nucleus pulposus of the disc. Given the recent advances in minimally invasive spine surgery, and developing body of work on stem cell manipulation and transplantation, stem cells are uniquely poised to bring about large-scale improvements in treatment and outcomes for degenerative disc disease. In this review we will first discuss the cellular and molecular factors influencing degeneration, and then examine the efficacy and difficulties of stem cell transplantation.Keywords: intervertebral disc degeneration, stem cells, disc disease, mesenchymal stem cells, stem cell transplantation
Rehabilitation Approaches in Macular Degeneration Patients
Maniglia, Marcello; Benoit R Cottereau; Soler, Vincent; Trotter, Yves
2016-01-01
Age related macular degeneration (AMD) is a visual disease that affects elderly population. It entails a progressive loss of central vision whose consequences are dramatic for the patient’s quality of life. Current rehabilitation programs are restricted to technical aids based on visual devices. They only temporarily improve specific visual functions such as reading skills. Considering the rapid increase of the aging population worldwide, it is crucial to intensify clinical research on AMD in...
Controllability of nonlinear degenerate parabolic cascade systems
Directory of Open Access Journals (Sweden)
Mamadou Birba
2016-08-01
Full Text Available This article studies of null controllability property of nonlinear coupled one dimensional degenerate parabolic equations. These equations form a cascade system, that is, the solution of the first equation acts as a control in the second equation and the control function acts only directly on the first equation. We prove positive null controllability results when the control and a coupling set have nonempty intersection.
Animal models of age related macular degeneration
Pennesi, Mark E.; Neuringer, Martha; Courtney, Robert J.
2012-01-01
Age related macular degeneration (AMD) is the leading cause of vision loss of those over the age of 65 in the industrialized world. The prevalence and need to develop effective treatments for AMD has lead to the development of multiple animal models. AMD is a complex and heterogeneous disease that involves the interaction of both genetic and environmental factors with the unique anatomy of the human macula. Models in mice, rats, rabbits, pigs and non-human primates have recreated many of the ...
Conceptual foundations of schizophrenia: I. Degeneration.
Barrett, R J
1998-10-01
This is the first of two papers that aim to identify some of the institutional processes of 19th century European psychiatry, and some prevailing cultural themes of that era that played a role in shaping the development of schizophrenia as a disease concept. Three areas of psychiatric history are examined: the first is concerned with the key figures who coined the concept of dementia praecox; the second with the rise of the asylum; and the third is to do with the ideology of 19th century psychiatric science and its relationship to a broader intellectual milieu. These three literatures are examined for common themes. The theme of degeneration is evident in all three literatures, and denotes both a biological process (neuro-degeneration) and a moral state (degeneracy). The idea of degeneration, a pervasive cultural theme of the 19th century, dominated psychiatric thinking long before schizophrenia was developed as a diagnostic category. It contributed to the ideational form-work that gave foundation, structure and shape to the concept of schizophrenia.
Propagation of Disturbances in Degenerate Quantum Systems
Chancellor, Nicholas
2011-01-01
Disturbances in gapless quantum many-body models are known to travel an unlimited distance throughout the system. Here, we explore this phenomenon in finite clusters with degenerate ground states. The specific model studied here is the one-dimensional J1-J2 Heisenberg Hamiltonian at and close to the Majumdar-Ghosh point. Both open and periodic boundary conditions are considered. Quenches are performed using a local magnetic field. The degenerate Majumdar-Ghosh ground state allows disturbances which carry quantum entanglement to propagate throughout the system, and thus dephase the entire system within the degenerate subspace. These disturbances can also carry polarization, but not energy, as all energy is stored locally. The local evolution of the part of the system where energy is stored drives the rest of the system through long-range entanglement. We also examine approximations for the ground state of this Hamiltonian in the strong field limit, and study how couplings away from the Majumdar-Ghosh point aff...
Visual hallucinations in patients with macular degeneration.
Holroyd, S; Rabins, P V; Finkelstein, D; Nicholson, M C; Chase, G A; Wisniewski, S C
1992-12-01
This study was undertaken to determine the prevalence of visual hallucinations in patients with macular degeneration, describe such hallucinations phenomenologically, and possibly determine factors predisposing to their development. Using a case-control design, the authors screened 100 consecutive patients with age-related macular degeneration for visual hallucinations. Each patient with visual hallucinations was matched to the next three patients without hallucinations. The patients and comparison subjects were compared in terms of scores on the Beck Depression Inventory, Eysenck Personality Questionnaire, Telephone Interview for Cognitive Status, and a structured questionnaire including demographic characteristics, family history, and medical and psychiatric history. Ophthalmologic data were obtained by chart review. Of the 100 patients, 13 experienced visual hallucinations. Four variables were significantly associated with having hallucinations: living alone, lower cognition score, history of stroke, and bilaterally worse visual acuity. Hallucinations were not associated with family or personal history of psychiatric disorder or with personality traits. In 11 (84.6%) of the 13 patients, the hallucinations had begun in association with an acute change in vision. These results indicate that visual hallucinations are prevalent among patients with macular degeneration. They appear unrelated to primary psychiatric disorder. The predisposing factors of bilaterally worse vision and living alone support an association with sensory deprivation, while history of stroke and worse cognition support a decreased cortical inhibition theory.
Symmetry, stability, and computation of degenerate lasing modes
Liu, David; Ge, Li; Hernandez, Felipe; Pick, Adi; Burkhardt, Stephan; Liertzer, Matthias; Rotter, Stefan; Johnson, Steven G
2016-01-01
We present a general method to obtain the stable lasing solutions for the steady-state ab-initio lasing theory (SALT) for the case of a degenerate symmetric laser in two dimensions (2d). We find that under most regimes (with one pathological exception), the stable solutions are clockwise and counterclockwise circulating modes, generalizing previously known results of ring lasers to all 2d rotational symmetry groups. Our method uses a combination of semi-analytical solutions close to lasing threshold and numerical solvers to track the lasing modes far above threshold. Near threshold, we find closed-form expressions for both circulating modes and other types of lasing solutions as well as for their linearized Maxwell--Bloch eigenvalues, providing a simple way to determine their stability without having to do a full nonlinear numerical calculation. Above threshold, we show that a key feature of the circulating mode is its "chiral" intensity pattern, which arises from spontaneous symmetry-breaking of mirror symme...
Activity loss and depression in age-related macular degeneration.
Rovner, Barry W; Casten, Robin J
2002-01-01
Age-related macular degeneration (AMD) is the most frequent cause of severe vision loss in older persons and is associated with high rates of disability and depression. The authors evaluated 51 patients with bilateral AMD to investigate the interrelationships of disease severity, disability, and depression and focused on loss of valued activities as an emblematic disabling consequence of AMD. They characterized depression by the Center for Epidemiologic Studies-Depression (CES-D) score, a syndromal state based on the CES-D, and as a level of distress (Index of Affective Suffering; IAS). Thirty subjects (58.8%) had loss of a valued, discretionary activity. They had worse visual acuity and more depressive symptoms and were represented in higher IAS levels than other subjects. Visual acuity was significantly correlated with IAS levels, but not with CES-D scores or syndromal depression. A regression model demonstrated that activity loss mediated the relationship between visual acuity and IAS level. Affective distress occurs in AMD, largely to the extent that valued activities are relinquished because of vision loss. IAS levels best illuminated this relationship, suggesting the value of this dimension of affective functioning in studies of the consequences of chronic disease.
Thermal dimension of quantum spacetime
Amelino-Camelia, Giovanni; Gubitosi, Giulia; Santos, Grasiele
2016-01-01
Recent results suggest that a crucial crossroad for quantum gravity is the characterization of the effective dimension of spacetime at short distances, where quantum properties of spacetime become significant. This is relevant in particular for various scenarios of "dynamical dimensional reduction" which have been discussed in the literature. We are here concerned with the fact that the related research effort has been based exclusively on analyses of the "spectral dimension", which involves an unphysical Euclideanization of spacetime and is highly sensitive to the off-shell properties of a theory. As here shown, different formulations of the same physical theory can have wildly different spectral dimension. We propose that dynamical dimensional reduction should be described in terms of the "thermal dimension" which we here introduce, a notion that only depends on the physical content of the theory. We analyze a few models with dynamical reduction both of the spectral dimension and of our thermal dimension, f...
[New drug therapy for retinal degeneration].
Ohguro, Hiroshi
2008-01-01
Retinitis pigmentosa (RP) is an inherited retinal degeneration characterized by nyctalopia, ring scotoma, and bone-spicule pigmentation of the retina. So far, no effective therapy has been found for RP. As a possible molecular etiology of RP, retina-specific gene deficits are most likely involved, but little has been identified in terms of intracellular mechanisms leading to retinal photoreceptor cell death at post-translational levels. In order to find an effective therapy for RP, we must look for underlying common mechanisms that are responsible for the development of RP, instead of designing a specific therapy for each of the RP types with different causes. Therefore, in the present study, several animal models with different causes of RP were studied, including (1)Royal College of Surgeons (RCS) rats with a deficit of retinal pigment epithelium (RPE) function caused by rhodopsin mutation; (2) P23H rats, (3) S334ter rats, (4) photo stress rats, (5) retinal degeneration (rd) mice with a deficit of phosphodiesterase(PDE) function; and (6) cancer-associated retinopathy (CAR) model rats with a deficit of recoverin-dependent photoreceptor adaptation function. In each of these models, the following assessments were made in order to elucidate common pathological mechanisms among the models: (1) retinal function assessed by electroretinogram (ERG), (2) retinal morphology, (3) retinoid analysis, (4) rhodopsin regeneration, (5) rhodopsin phosphorylation and dephosphorylation, and (6) cytosolic cGMP levels. We found that unregulated photoreceptor adaptation processes caused by an imbalance of rhodopsin phosphorylation and dephosphorylation caused retinal dysfunction leading to photoreceptor cell death. As possible candidate drugs for normalizing these retinal dysfunctions and stopping further retinal degeneration, nilvadipine, a Ca channel blocker, retinoid derivatives, and anthocyanine were chosen and tested to determine their effect on the above animal models with
Graviscalars from higher-dimensional metrics and curvature-Higgs mixing
Giudice, Gian Francesco; Wells, J D; Giudice, Gian F.; Rattazzi, Riccardo; Wells, James D.
2001-01-01
We investigate the properties of scalar fields arising from gravity propagating in extra dimensions. In the scenario of large extra dimensions, proposed by Arkani-Hamed, Dimopoulos and Dvali (1998), graviscalar Kaluza-Klein excitations are less important than the spin-2 counterparts in most processes. However, there are important exceptions. The Higgs boson can mix to these particles by coupling to the Ricci scalar. Because of the large number of states involved, this mixing leads, in practice, to a sizeable invisible width for the Higgs. In the Randall-Sundrum scenario, the only graviscalar is the radion. It can be produced copiously at hadron colliders by virtue of its enhanced coupling to two gluons through the trace anomaly of QCD. We study both the production and decay of the radion, and compare it to the Standard Model Higgs boson. Furthermore, we find that radion detectability depends crucially on the curvature-Higgs boson mixing parameter. (29 refs).
It is a Graviton! or maybe not
Fok, Ricky; Lewis, Randy; Sanz, Veronica
2012-01-01
The discovery of Kaluza-Klein (KK) gravitons is a smoking gun of extra dimen- sions. Other scenarios, however, could give rise to spin-two resonances of a new strongly- coupled sector and act as impostors. In this paper we prove that a spin-two resonance does not couple to the Standard Model through dimension-four operators. We then show that the massive graviton and its impostor both couple to the Standard Model through the same dimension-five operators. Therefore the spin determination is identical. Never- theless, we also show that one can use the ratio of branching ratios to photons and to jets for distinguishing between KK gravitons and their impostors. The capacity to distinguish between KK gravitons and impostors is a manifestation of the breakdown of the duality between AdS and strongly-coupled theories.
Cosmology in nonlinear multidimensional gravity and the Casimir effect
Bolokhov, S. V.; Bronnikov, K. A.
2017-01-01
We study the possible cosmological models in Kaluza-Klein-type multidimensional gravity with a curvature-nonlinear Lagrangian and a spherical extra space, taking into account the Casimir energy. First, we find a minimum of the effective potential of extra dimensions, leading to a physically reasonable value of the effective cosmological constant in our 4D space-time. In this model, the huge Casimir energy density is compensated by a fine-tuned contribution of the curvature-nonlinear terms in the original action. Second, we present a viable model with slowly evolving extra dimensions and power-law inflation in our space-time. In both models, the results formulated in Einstein and Jordan frames are compared.
Neutrino masses and mixing from S4 flavor twisting
Ishimori, Hajime; Tanimoto, Morimitsu; Watanabe, Atsushi
2010-01-01
We discuss a neutrino mass model based on the S4 discrete symmetry where the symmetry breaking is triggered by the boundary conditions of the bulk right-handed neutrino in the fifth spacial dimension. While the symmetry restricts bare mass parameters to flavor-diagonal forms, the viable mixing angles emerge from the wave functions of the Kaluza-Klein modes which carry symmetry breaking effect. The magnitudes of the lepton mixing angles, especially the reactor angle is related to the neutrino mass patterns and the model will be tested in future neutrino experiments, e.g., an early (late) discovery of the reactor angle favors the normal (inverted) hierarchy. The size of extra dimension has a connection to the possible mass spectrum; a small (large) volume corresponds to the normal (inverted) mass hierarchy.
Shadows of the Planck Scale The Changing Face of Compactification Geometry
Dienes, Keith R; Dienes, Keith R.; Mafi, Arash
2002-01-01
By studying the effects of the shape moduli associated with toroidal compactifications, we demonstrate that Planck-sized extra dimensions can cast significant ``shadows'' over low-energy physics. These shadows can greatly distort our perceptions of the compactification geometry associated with large extra dimensions, and place a fundamental limit on our ability to probe the geometry of compactification simply by measuring Kaluza-Klein states. We also discuss the interpretation of compactification radii and hierarchies in the context of geometries with non-trivial shape moduli. One of the main results of this paper is that compactification geometry is effectively renormalized as a function of energy scale, with ``renormalization group equations'' describing the ``flow'' of geometric parameters such as compactification radii and shape angles as functions of energy.
Dark energy observational evidence and theoretical models
Novosyadlyj, B; Shtanov, Yu; Zhuk, A
2013-01-01
The book elucidates the current state of the dark energy problem and presents the results of the authors, who work in this area. It describes the observational evidence for the existence of dark energy, the methods and results of constraining of its parameters, modeling of dark energy by scalar fields, the space-times with extra spatial dimensions, especially Kaluza---Klein models, the braneworld models with a single extra dimension as well as the problems of positive definition of gravitational energy in General Relativity, energy conditions and consequences of their violation in the presence of dark energy. This monograph is intended for science professionals, educators and graduate students, specializing in general relativity, cosmology, field theory and particle physics.
Anomalous Dimensions of Conformal Baryons
DEFF Research Database (Denmark)
Pica, Claudio; Sannino, Francesco
2016-01-01
We determine the anomalous dimensions of baryon operators for the three color theory as function of the number of massless flavours within the conformal window to the maximum known order in perturbation theory. We show that the anomalous dimension of the baryon is controllably small, within...... the $\\delta$-expansion, for a wide range of number of flavours. We also find that this is always smaller than the anomalous dimension of the fermion mass operator. These findings challenge the partial compositeness paradigm....
Beta Function and Anomalous Dimensions
Pica, Claudio
2010-01-01
We demonstrate that it is possible to determine the coefficients of an all-order beta function linear in the anomalous dimensions using as data the two-loop coefficients together with the first one of the anomalous dimensions which are universal. The beta function allows to determine the anomalous dimension of the fermion masses at the infrared fixed point, and the resulting values compare well with the lattice determinations.
Anomalous Dimensions of Conformal Baryons
Pica, Claudio
2016-01-01
We determine the anomalous dimensions of baryon operators for the three color theory as function of the number of massless flavours within the conformal window to the maximum known order in perturbation theory. We show that the anomalous dimension of the baryon is controllably small for a wide range of number of flavours. We also find that this is always smaller than the anomalous dimension of the fermion mass operator. These findings challenge the partial compositeness paradigm.
Prakash, Manu
2011-01-01
Diversity and specialization of behavior in insects is unmatched. Insects hop, walk, run, jump, row, swim, glide and fly to propel themselves in a variety of environments. We have uncovered an unusual mode of propulsion of aerodynamic flight in two dimensions in Waterlilly Beetles \\emph{(Galerucella)}. The adult beetles, often found in water lilly ponds, propel themselves strictly in a two-dimensional plane on the surface of water via flapping wing flight. Here we analyze the aerodynamics of this peculiar flight mode with respect to forces exerted on the organism during flight. The complexity of 2-D flight is captured by accounting for additional forces beyond gravitational, thrust, lift and drag, exerted on the insect body in 3D flight. Understanding this constrained propulsion mode requires accounting for viscous drag, surface tension, buoyancy force, and capillary-wave drag. Moreover, dramatic differences exist in the magnitude of the resultant forces in 2D vs. 3D flight. Here, in this fluid dynamics video...
van Houselt, A.; Schäfer, J.; Zandvliet, H. J. W.; Claessen, R.
2013-01-01
With modern microelectronics moving towards smaller and smaller length scales on the (sub-) nm scale, quantum effects (apart from band structure and band gaps) have begun to play an increasingly important role. This especially concerns dimensional confinement to 2D (high electron mobility transistors and integer/fractional quantum Hall effect physics, graphene and topological insulators) and 1D (with electrical connections eventually reaching the quantum limit). Recent developments in the above-mentioned areas have revealed that the properties of electron systems become increasingly exotic as one progresses from the 3D case into lower dimensions. As compared to 2D electron systems, much less experimental progress has been achieved in the field of 1D electron systems. The main reason for the lack of experimental results in this field is related to the difficulty of realizing 1D electron systems. Atom chains created in quantum mechanical break junction set-ups are too short to exhibit the typically 1D signatures. As an alternative, atomic chains can be produced on crystal surfaces, either via assembling them one-by-one using a scanning tunnelling microscope or via self-assembly. The drawback of the latter systems is that the atomic chains are not truly 1D since they are coupled to the underlying crystal and sometimes even to the neighbouring chains. In retrospect, this coupling turns out to be an absolute necessity in the experiment since true 1D systems are disordered at any non-zero temperature [1]. The coupling to the crystal and/or neighbouring chains shifts the phase transition, for example, a Peierls instability, to a non-zero temperature and thus allows experiments to be performed in the ordered state. Here, we want to emphasize that the electronic properties of the 1D electron system are fundamentally different from its 2D and 3D counterparts. The Fermi liquid theory, which is applicable to 2D and 3D electron systems, breaks down spectacularly in the 1D case
DIMENSION STONE DEPOSITS IN CROATIA
Directory of Open Access Journals (Sweden)
Branko Crnković
1993-12-01
Full Text Available The geology, petrographycal composition and properties of dimension stone deposits in Croatia are described. Dimension stone deposits in the conception of mobilistic view of the genesis and structure of Dinarides, as well as after stratigraphic units, are considered. Valuation of the dimension stones of the active quarries is exposed. The marketable categories of dimension stone in Croatia are different varietes of limestones and calcareous clastites, primarly of Cretaceous age, and to lesser degree of Jurassic and Paleogene. The greatest part of deposits is concentrated in the Adriatic carbonate platform or Adriaticum.
Exterior dimension of fat fractals
Grebogi, C.; Mcdonald, S. W.; Ott, E.; Yorke, J. A.
1985-01-01
Geometric scaling properties of fat fractal sets (fractals with finite volume) are discussed and characterized via the introduction of a new dimension-like quantity which is called the exterior dimension. In addition, it is shown that the exterior dimension is related to the 'uncertainty exponent' previously used in studies of fractal basin boundaries, and it is shown how this connection can be exploited to determine the exterior dimension. Three illustrative applications are described, two in nonlinear dynamics and one dealing with blood flow in the body. Possible relevance to porous materials and ballistic driven aggregation is also noted.
Institute of Scientific and Technical Information of China (English)
蒋威; 郑祖庥; 王志成
2001-01-01
In this paper we establish V-functional criterion theorems for the stability of general autonomous degenerate differential systems with delay. Then for a kind of degenerate differential systems with delay-the mixed systems of difference differential systems with difference systems, we give a specific form of V-functional, a corresponding criterion theorem and examples. Finally, for the stability of two dimension degenerate differential systems with delay, we obtain the necessary and sufficient condition for the existence of a kind of V-functional.
Degenerate Bogdanov-Takens bifurcations in a one-dimensional transport model of a fusion plasma
de Blank, H. J.; Kuznetsov, Yu. A.; Pekkér, M. J.; Veldman, D. W. M.
2016-09-01
Experiments in tokamaks (nuclear fusion reactors) have shown two modes of operation: L-mode and H-mode. Transitions between these two modes have been observed in three types: sharp, smooth and oscillatory. The same modes of operation and transitions between them have been observed in simplified transport models of the fusion plasma in one spatial dimension. We study the dynamics in such a one-dimensional transport model by numerical continuation techniques. To this end the MATLAB package CL_MATCONTL was extended with the continuation of (codimension-2) Bogdanov-Takens bifurcations in three parameters using subspace reduction techniques. During the continuation of (codimension-2) Bogdanov-Takens bifurcations in 3 parameters, generically degenerate Bogdanov-Takens bifurcations of codimension-3 are detected. However, when these techniques are applied to the transport model, we detect a degenerate Bogdanov-Takens bifurcation of codimension 4. The nearby 1- and 2-parameter slices are in agreement with the presence of this codimension-4 degenerate Bogdanov-Takens bifurcation, and all three types of L-H transitions can be recognized in these slices. The same codimension-4 situation is observed under variation of the additional parameters in the model, and under some modifications of the model.
Warped Geometry in Higher Dimensions with an Orbifold Extra Dimension
Ito, M
2001-01-01
We solve the Einstein equations in higher dimensions with warped geometry where an extra dimension is assumed to have orbifold symmetry, $S^{1}/Z_{2}$. The setup we consider here is an extension to (5+D)-dimensions of the 5-dimensional Randall-Sundrum model, and two hidden brane and observable brane are fixed on orbifold. Anisotropic cosmological constant on each brane with (4+D)-dimensional spacetime is assumed, and the warped metric of 4-dimensions is generally different from one of extra D-dimensions. It is pointed out that the form of metric depends on both the sign of bulk cosmological constant and initial condition of brane world. Furthermore, anisotropic cosmological constant on each brane can be realized due to the presence of brane.
Saliency of social comparison dimensions
Kuyper, H.
2007-01-01
The present article discusses a theory of the saliency of social comparison dimensions and presents the results of an experiment about the effects of two different experimental situations on the saliency of exterior, task-related and socio-emotional dimensions. Saliency was operationalized with a
Dimensioning, Tolerancing, and Machine Finishes.
Adams, George C.
Intended for use with the vocational education student interested in technical drawing, this guide provides answers to questions relating to dimensioning and tolerancing machine drawings. It also gives examples of standard dimensioning practices, tolerancing applications, and finish applications. The problems and examples presented are based on…
Anomalous Dimensions of Conformal Baryons
DEFF Research Database (Denmark)
Pica, Claudio; Sannino, Francesco
2016-01-01
We determine the anomalous dimensions of baryon operators for the three color theory as function of the number of massless flavours within the conformal window to the maximum known order in perturbation theory. We show that the anomalous dimension of the baryon is controllably small, within...
Mathematics Teachers' Criteria of Dimension
Ural, Alattin
2014-01-01
The aim of the study is to determine mathematics teachers' decisions about dimensions of the geometric figures, criteria of dimension and consistency of decision-criteria. The research is a qualitative research and the model applied in the study is descriptive method on the basis of general scanning model. 15 mathematics teachers attended the…
The Hausdorff Dimension of Sections
Institute of Scientific and Technical Information of China (English)
Min NIU; Lifeng XI
2007-01-01
The notion of finite-type open set condition is defined to calculate the Hausdorff dimensions of the sections of some self-similar sets, such as the dimension of intersection of the Koch curve and the line x = a with a ∈(Q).
Anomalous Dimensions of Conformal Baryons
DEFF Research Database (Denmark)
Pica, Claudio; Sannino, Francesco
2016-01-01
We determine the anomalous dimensions of baryon operators for the three color theory as function of the number of massless flavours within the conformal window to the maximum known order in perturbation theory. We show that the anomalous dimension of the baryon is controllably small, within the $...
Beta Function and Anomalous Dimensions
DEFF Research Database (Denmark)
Pica, Claudio; Sannino, Francesco
2011-01-01
We demonstrate that it is possible to determine the coefficients of an all-order beta function linear in the anomalous dimensions using as data the two-loop coefficients together with the first one of the anomalous dimensions which are universal. The beta function allows to determine the anomalou...
Degenerate Neutrinos in Left Right Symmetric Theory
Joshipura, Anjan S.
1994-01-01
Various hints on the neutrino masses namely, ({\\em i}) the solar neutrino deficit ({\\em ii}) the atmospheric neutrino deficit ({\\em iii}) the need for the dark matter and/or ({\\em iv}) the non-zero neutrinoless double beta decay collectively imply that all the three neutrinos must be nearlty degenerate. This feature can be understood in the left right symmetric theory. We present a model based on the group $SU(2)_{L}\\times SU(2)_R\\times U(1)_{B-L}\\times SU(2)_H$ which can explain the required...
REITERATED HOMOGENIZATION OF DEGENERATE NONLINEAR ELLIPTIC EQUATIONS
Institute of Scientific and Technical Information of China (English)
无
2002-01-01
The authors study homogenization of some nonlinear partial differential equations of the form -div (a (hx,h2x,Duh)) = f,where a is periodic in the first two arguments and monotone in the third.In particular the case where a satisfies degenerated structure conditions is studied.It is proved that uh converges weakly in Wo1.1 (Ω) to the unique solution of a limit problem as h →∞.Moreover,explicit expressions for the limit problem are obtained.
Length spectra and degeneration of flat metrics
Duchin, Moon; Rafi, Kasra
2009-01-01
In this paper we consider flat metrics (semi-translation structures) on surfaces of finite type. There are two main results. The first is a complete description of when a set of simple closed curves is spectrally rigid, that is, when the length vector determines a metric among the class of flat metrics. Secondly, we give an embedding into the space of geodesic currents and use this to get a boundary for the space of flat metrics. The geometric interpretation is that flat metrics degenerate to "mixed structures" on the surface: part flat metric and part measured foliation.
Aneutronic Fusion in a Degenerate Plasma
Energy Technology Data Exchange (ETDEWEB)
S. Son; N.J. Fisch
2004-09-03
In a Fermi-degenerate plasma, the electronic stopping of a slow ion is smaller than that given by the classical formula, because some transitions between the electron states are forbidden. The bremsstrahlung losses are then smaller, so that the nuclear burning of an aneutronic fuel is more efficient. Consequently, there occurs a parameter regime in which self-burning is possible. Practical obstacles in this regime that must be overcome before net energy can be realized include the compression of the fuel to an ultra dense state and the creation of a hot spot.