BPS Spectra, Barcodes and Walls
Cirafici, Michele
2015-01-01
BPS spectra give important insights into the non-perturbative regimes of supersymmetric theories. Often from the study of BPS states one can infer properties of the geometrical or algebraic structures underlying such theories. In this paper we approach this problem from the perspective of persistent homology. Persistent homology is at the base of topological data analysis, which aims at extracting topological features out of a set of points. We use these techniques to investigate the topological properties which characterize the spectra of several supersymmetric models in field and string theory. We discuss how such features change upon crossing walls of marginal stability in a few examples. Then we look at the topological properties of the distributions of BPS invariants in string compactifications on compact threefolds, used to engineer black hole microstates. Finally we discuss the interplay between persistent homology and modularity by considering certain number theoretical functions used to count dyons i...
Wall Crossing of BPS States on the Conifold from Seiberg Duality and Pyramid Partitions
Chuang, Wu-yen
2008-01-01
In this paper we study the relation between pyramid partitions with a general empty room configuration (ERC) and the BPS states of D-branes on the resolved conifold. We find that the generating function for pyramid partitions with a length n ERC is exactly the same as the D6/D2/D0 BPS partition function on the resolved conifold in particular Kaehler chambers. We define a new type of pyramid partition with a finite ERC that counts the BPS degeneracies in certain other chambers. The D6/D2/D0 partition functions in different chambers were obtained by applying the wall crossing formula. On the other hand, the pyramid partitions describe $T^3$ fixed points of the moduli space of a quiver quantum mechanics. This quiver arises after we apply Seiberg dualities to the D6/D2/D0 system on the conifold and choose a particular set of FI parameters. The arrow structure of the dual quiver is confirmed by computation of the Ext group between the sheaves. We show that the superpotential and the stability condition of the dual...
BPS state counting using wall-crossing, holomorphic anomalies and modularity
Wotschke, Thomas
2013-05-15
In this thesis we examine the counting of BPS states using wall-crossing, holomorphic anomalies and modularity. We count BPS states that arise in two setups: multiple M5-branes wrapping P x T{sup 2}, where P denotes a divisor inside a Calabi-Yau threefold and topological string theory on elliptic Calabi-Yau threefolds. The first setup has a dual description as type IIA string theory via a D4-D2-D0 brane system. Furthermore it leads to two descriptions depending on the size of P and T{sup 2} relative to each other. For the case of a small divisor P this setup is described by the (0,4) Maldacena-Strominger-Witten conformal field theory of a black hole in M-theory and for the case of small T{sup 2} the setup can by described by N=4 topological Yang-Mills theory on P. The BPS states are counted by the modified elliptic genus, which can be decomposed into a vector-valued modular form that provides the generating function for the BPS invariants and a Siegel-Narain theta function. In the first part we discuss the holomorphic anomaly of the modified elliptic genus for the case of two M5-branes and divisors with b{sup +}{sub 2}(P)=1. Due to the wall-crossing effect the change in the generating function is captured by an indefinite theta function, which is a mock modular form. We use the Kontsevich-Soibelman wall-crossing formula to determine the jumps in the modified elliptic genus. Using the regularisation procedure for mock modular forms of Zwegers, modularity can be restored at the cost of holomorphicity. We show that the non-holomorphic completion is due to bound states of single M5-branes. At the attractor point in the moduli space we prove the holomorphic anomaly equation, which is compatible with the holomorphic anomaly equations observed in the context of N=4 Yang-Mills theory on P{sup 2} and E-strings on a del Pezzo surface. We calculate the generating functions of BPS invariants for the divisors P{sup 2}, F{sub 0}, F{sub 1} and the del Pezzo surface dP{sub 8} and
BPS state counting using wall-crossing, holomorphic anomalies and modularity
In this thesis we examine the counting of BPS states using wall-crossing, holomorphic anomalies and modularity. We count BPS states that arise in two setups: multiple M5-branes wrapping P x T2, where P denotes a divisor inside a Calabi-Yau threefold and topological string theory on elliptic Calabi-Yau threefolds. The first setup has a dual description as type IIA string theory via a D4-D2-D0 brane system. Furthermore it leads to two descriptions depending on the size of P and T2 relative to each other. For the case of a small divisor P this setup is described by the (0,4) Maldacena-Strominger-Witten conformal field theory of a black hole in M-theory and for the case of small T2 the setup can by described by N=4 topological Yang-Mills theory on P. The BPS states are counted by the modified elliptic genus, which can be decomposed into a vector-valued modular form that provides the generating function for the BPS invariants and a Siegel-Narain theta function. In the first part we discuss the holomorphic anomaly of the modified elliptic genus for the case of two M5-branes and divisors with b+2(P)=1. Due to the wall-crossing effect the change in the generating function is captured by an indefinite theta function, which is a mock modular form. We use the Kontsevich-Soibelman wall-crossing formula to determine the jumps in the modified elliptic genus. Using the regularisation procedure for mock modular forms of Zwegers, modularity can be restored at the cost of holomorphicity. We show that the non-holomorphic completion is due to bound states of single M5-branes. At the attractor point in the moduli space we prove the holomorphic anomaly equation, which is compatible with the holomorphic anomaly equations observed in the context of N=4 Yang-Mills theory on P2 and E-strings on a del Pezzo surface. We calculate the generating functions of BPS invariants for the divisors P2, F0, F1 and the del Pezzo surface dP8 and dP9 ((1)/(2) K3). In the second part we study the quantum
BPS domain walls from backreacted orientifolds
Blåbäck, Johan; Van Riet, Thomas; Vercnocke, Bert
2013-01-01
Compactifications with D-brane and orientifold sources lead to standard gauged supergravity theories if the sources are smeared over the internal directions. It is therefore of interest to find how the solutions described by the gauged supergravity are altered by properly localising the sources. In this paper we analyse this for BPS domain wall solutions in the seven-dimensional gauged supergravity obtained from an O6 toroidal orientifold compactification in massive IIA supergravity. This is one of the simplest no-scale supergravities that can be constructed and analysed in full detail. We find and discuss the BPS domain walls both when the O6 planes are smeared and localised. When the O6 planes are localised the domain wall solutions live in a warped compactification. In order to get explicit expressions we also consider the non-compact versions of the solutions for which the O6 planes have been traded for D6 branes. Through T-duality we obtain partially localised solutions for compactifications to four dime...
Global structure of moduli space for BPS walls
We study the global structure of the moduli space of BPS walls in the Higgs branch of supersymmetric theories with eight supercharges. We examine the structure in the neighborhood of a special Lagrangian submanifold M, and find that the dimension of the moduli space can be larger than that naively suggested by the index theorem, contrary to previous examples of BPS solitons. We investigate BPS wall solutions in an explicit example of M using Abelian gauge theory. Its Higgs branch turns out to contain several special Lagrangian submanifolds including M. We show that the total moduli space of BPS walls is the union of these submanifolds. We also find interesting dynamics between BPS walls as a by-product of the analysis. Namely, mutual repulsion and attraction between BPS walls sometimes forbid a movement of a wall and lock it in a certain position; we also find that a pair of walls can transmute to another pair of walls with different tension after they pass through
Exact BPS domain walls at finite gauge coupling
Blaschke, Filip
2016-01-01
Bogomol'nyi-Prasad-Sommerfield solitons in models with spontaneously broken gauge symmetry have been intensively studied at infinite gauge coupling limit, where the governing equation -- so-called master equation -- is exactly solvable. Except of handful of special solutions, the standing impression is that analytic results at finite coupling are generally unavailable. The aim of this paper is to demonstrate, using domain walls in Abelian-Higgs models as a simplest example, that exact solitons at finite gauge coupling can be readily obtained, if the number of Higgs fields ($N_F$) is large enough. In particular, we present a family of exact solutions, describing $N$ domain walls at arbitrary positions in models with at least $N_F \\geq 2N+1$. We have also found that adding together any pair of solution can produce a new exact solution, if the combined tension is below certain limit.
Pioline, Boris
2015-01-01
In $D=4,N=2$ theories on $R^{3,1}$, the index receives contributions not only from single-particle BPS states, counted by the BPS indices, but also from multi-particle states made of BPS constituents. In a recent work [arXiv:1406.2360], a general formula expressing the index in terms of the BPS indices was proposed, which is smooth across walls of marginal stability and reproduces the expected single-particle contributions. In this note, I analyze the two-particle contributions predicted by this formula, and show agreement with the spectral asymmetry of the continuum of scattering states in the supersymmetric quantum mechanics of two non-relativistic, mutually non-local dyons. This provides a physical justification for the error function profile used in the mathematics literature on indefinite theta series, and in the physics literature on black hole partition functions.
Semiclassical framed BPS states
Moore, Gregory W; Bleeken, Dieter Van den
2015-01-01
We provide a semiclassical description of framed BPS states in four-dimensional N = 2 super Yang-Mills theories probed by 't Hooft defects, in terms of a supersymmetric quantum mechanics on the moduli space of singular monopoles. Framed BPS states, like their ordinary counterparts in the theory without defects, are associated with the L^2 kernel of certain Dirac operators on moduli space, or equivalently with the L^2 cohomology of related Dolbeault operators. The Dirac/Dolbeault operators depend on two Cartan-valued Higgs vevs. We conjecture a map between these vevs and the Seiberg-Witten special coordinates, consistent with a one-loop analysis and checked in examples. The map incorporates all perturbative and nonperturbative corrections that are relevant for the semiclassical construction of BPS states, over a suitably defined weak coupling regime of the Coulomb branch. We use this map to translate wall crossing formulae and the no exotics theorem to statements about the Dirac/Dolbeault operators. The no exo...
BPS Domain Walls in super Yang-Mills and Landau-Ginzburg models
We study domain walls in two different extensions of super Yang-Mills characterized by the absence of a logarithmic term in their effective superpotential. The models, defined by the usual gaugino condensate and an extra field Y, give different patterns of domain walls despite both leading to the same effective limit for heavy Y, i.e. the Veneziano-Yankielowicz effective Lagrangian of super Yang-Mills. We explain the origin of those differences and also give a physical motivation for introducing the field Y. (author)
BPS spectrum of Argyres-Douglas theory via spectral network
Maruyoshi, Kazunobu; Yan, Wenbin
2013-01-01
We study the BPS spectrum of four-dimensional N=2 superconformal field theory of Argyres-Douglas type, obtained via twisted compactification of six-dimensional A_{N-1} (2,0) theory on a sphere with an irregular puncture, by using spectral networks. We give strong evidence of the equivalence of N=2 superconformal field theories from six-dimensional theories of different ranks by systematically comparing the chamber structure and wall-crossing phenomena.
Quantum Black Holes, Wall Crossing, and Mock Modular Forms
Dabholkar, Atish; Zagier, Don
2012-01-01
We show that the meromorphic Jacobi form that counts the quarter-BPS states in N=4 string theories can be canonically decomposed as a sum of a mock Jacobi form and an Appell-Lerch sum. The quantum degeneracies of single-centered black holes are Fourier coefficients of this mock Jacobi form, while the Appell-Lerch sum captures the degeneracies of multi-centered black holes which decay upon wall-crossing. The completion of the mock Jacobi form restores the modular symmetries expected from $AdS_3/CFT_2$ holography but has a holomorphic anomaly reflecting the non-compactness of the microscopic CFT. For every positive integral value m of the magnetic charge invariant of the black hole, our analysis leads to a special mock Jacobi form of weight two and index m, which we characterize uniquely up to a Jacobi cusp form. This family of special forms and another closely related family of weight-one forms contain almost all the known mock modular forms including the mock theta functions of Ramanujan, the generating funct...
Wall-Crossing Holomorphic Anomaly and Mock Modularity of Multiple M5-Branes
Alim, Murad; Haghighat, Babak; Hecht, Michael; Klemm, Albrecht; Rauch, Marco; Wotschke, Thomas
2015-11-01
Using wall-crossing formulae and the theory of mock modular forms we derive a holomorphic anomaly equation for the modified elliptic genus of two M5-branes wrapping a rigid divisor inside a Calabi-Yau manifold. The anomaly originates from restoring modularity of an indefinite theta-function capturing the wall-crossing of BPS invariants associated to D4-D2-D0 brane systems. We show the compatibility of this equation with anomaly equations previously observed in the context of topological Yang-Mills theory on and E-strings obtained from wrapping M5-branes on a del Pezzo surface. The non-holomorphic part is related to the contribution originating from bound-states of singly wrapped M5-branes on the divisor. We show in examples that the information provided by the anomaly is enough to compute the BPS degeneracies for certain charges. We further speculate on a natural extension of the anomaly to higher D4-brane charge.
Knots, BPS States, and Algebraic Curves
Garoufalidis, Stavros; Kucharski, Piotr; Sułkowski, Piotr
2016-08-01
We analyze relations between BPS degeneracies related to Labastida-Mariño-Ooguri-Vafa (LMOV) invariants and algebraic curves associated to knots. We introduce a new class of such curves, which we call extremal A-polynomials, discuss their special properties, and determine exact and asymptotic formulas for the corresponding (extremal) BPS degeneracies. These formulas lead to nontrivial integrality statements in number theory, as well as to an improved integrality conjecture, which is stronger than the known M-theory integrality predictions. Furthermore, we determine the BPS degeneracies encoded in augmentation polynomials and show their consistency with known colored HOMFLY polynomials. Finally, we consider refined BPS degeneracies for knots, determine them from the knowledge of super-A-polynomials, and verify their integrality. We illustrate our results with twist knots, torus knots, and various other knots with up to 10 crossings.
Gukov, Sergei; Saberi, Ingmar; Stosic, Marko; Sulkowski, Piotr
2015-01-01
This paper provides both a detailed study of color-dependence of link homologies, as realized in physics as certain spaces of BPS states, and a broad study of the behavior of BPS states in general. We consider how the spectrum of BPS states varies as continuous parameters of a theory are perturbed. This question can be posed in a wide variety of physical contexts, and we answer it by proposing that the relationship between unperturbed and perturbed BPS spectra is described by a spectral sequence. These general considerations unify previous applications of spectral sequence techniques to physics, and explain from a physical standpoint the appearance of many spectral sequences relating various link homology theories to one another. We also study structural properties of colored HOMFLY homology for links and evaluate Poincar\\'e polynomials in numerous examples. Among these structural properties is a novel "sliding" property, which can be explained by using (refined) modular $S$-matrix. This leads to the identifi...
Seo, Jihye
2012-01-01
N=2 Seiberg-Witten theories allow an interesting interplay between the Argyres-Douglas loci, singularity structures and wall-crossing formulae. In this paper we investigate this connection by first studying the singularity structures of hyper-elliptic Seiberg-Witten curves for pure N=2 gauge theories with SU(r+1) and Sp(2r) gauge groups, and propose new methods to locate the Argyres-Douglas loci in the moduli space, where multiple mutually non-local BPS states become massless. In a region of the moduli space, we compute dyon charges for all 2r+2 and 2r+1 massless dyons for SU(r+1) and Sp(2r) gauge groups respectively for rank r>1. From here we elucidate the connection to the wall-crossing phenomena for pure Sp(4) Seiberg-Witten theory near the Argyres-Douglas loci, despite our emphasis being only at the massless sector of the BPS spectra. We also present 2r-1 candidates for the maximal Argyres-Douglas points for pure SO(2r+1) Seiberg-Witten theory.
Gudnason, Sven Bjarke; Sawado, Nobuyuki
2015-01-01
The BPS Skyrme model has many exact analytic solutions in flat space. We generalize the model to a curved space or spacetime and find that the solutions can only be BPS for a constant time-time component of the metric tensor. We find exact solutions on the curved spaces: a 3-sphere and a 3-hyperboloid; and we further find an analytic gravitating Skyrmion on the 3-sphere. For the case of a nontrivial time-time component of the metric, we suggest a potential for which we find analytic solutions on anti-de Sitter and de Sitter spacetimes in the limit of no gravitational backreaction. We take the gravitational coupling into account in numerical solutions and show that they are well approximated by the analytic solutions for weak gravitational coupling.
Wall-Crossing in Genus Zero Landau-Ginzburg Theory
Ross, Dustin; Ruan, Yongbin
2014-01-01
We study genus zero wall-crossing for a family of moduli spaces introduced recently by Fan-Farvis-Ruan. The family has a wall and chamber structure relative to a positive rational parameter. For a Fermat quasi-homogeneous polynomial W (not necessarily Calabi-Yau type), we study natural generating functions of invariants associated to these moduli spaces. Our wall-crossing formula relates the generating functions by showing that they all lie on the same Lagrangian cone associated to the Fan-Ja...
Ioannidou, Theodora
2016-01-01
An extended version of the BPS Skyrme model that admits time-dependent solutions is discussed. Initially, by introducing a power law at the original potential term of the BPS Skyrme model the existence, stability and structure of the corresponding solutions is investigated. Then, the frequencies and half-lifes of the radial oscillations of the constructed time-dependent solutions are determined.
Non-perturbative effects and wall-crossing from topological strings
We argue that the Gopakumar-Vafa interpretation of the topological string partition function can be used to compute and resum certain non-perturbative brane instanton effects of type II CY compactifications. In particular the topological string A-model encodes the non-perturbative corrections to the hypermultiplet moduli space metric from general D1/D(-1)-brane instantons in 4d N = 2 IIB models. We also discuss the reduction to 4d N = 1 by fluxes and/or orientifolds and/or D-branes, and the prospects to resum brane instanton contributions to non-perturbative superpotentials. We argue that the connection between non-perturbative effects and the topological string underlies the continuity of non-perturbative effects across lines of BPS stability. We also confirm this statement in mirror B-model matrix model examples, relating matrix model instantons to non-perturbative D-brane instantons. The computation of non-perturbative effects from the topological string requires a 3d circle compactification and T-duality, relating effects from particles and instantons, reminiscent of that involved in the physical derivation of the Kontsevich-Soibelmann wall-crossing formula.
Superfluid properties of BPS monopoles
Lantsman, L
2006-01-01
This paper is devoted to demonstrating manifest superfluid properties of the Minkowskian Higgs model with vacuum BPS monopole solutions at assuming the "continuous" $\\sim S^2$ vacuum geometry in that model. It will be also argued that point hedgehog topological defects are present in the Minkowskian Higgs model with BPS monopoles. It turns out, and we show this, that the enumerated phenomena are compatible with the Faddeev-Popov "heuristic" quantization of the Minkowskian Higgs model with vacuum BPS monopoles, coming to fixing the Weyl (temporal) gauge $A_0=0$ for gauge fields $A$ in the Faddeev-Popov path integral.
Analytic continuation of a parametric polytope and wall-crossing
Berline, Nicole
2011-01-01
We define a set theoretic "analytic continuation" of a polytope defined by inequalities. For the regular values of the parameter, our construction coincides with the parallel transport of polytopes in a mirage introduced by Varchenko. We determine the set-theoretic variation when crossing a wall in the parameter space, and we relate this variation to Paradan's wall-crossing formulas for integrals and discrete sums. As another application, we refine the theorem of Brion on generating functions of polytopes and their cones at vertices. We describe the relation of this work with the equivariant index of a line bundle over a toric variety and Morelli constructible support function.
Connecting Localization and Wall-Crossing via D-Branes
Chang, Chih-Kai; Jain, Dharmesh; Lee, Norton
2015-01-01
We demonstrate explicitly that the vacuum expectation values (vevs) of BPS line operators in 4d N=2 super Yang-Mills theory compactified on a circle, computed by localization techniques, can be expanded in terms of Darboux coordinates as proposed by Gaiotto, Moore, and Neitzke [arXiv:1006.0146]. However, we need to refine the expansion by including additional novel monopole bubbling contributions to obtain a precise match. Using D-brane realization of these singular BPS line operators, we derive and incorporate the monopole bubbling contributions as well as predict the degeneracies of framed BPS states contributing to the line operator vevs in the limit of vanishing simultaneous spatial and R-symmetry rotation fugacity parameter.
Halyo, Edi
2009-01-01
We describe domain walls that live on $A_2$ and $A_3$ singularities. The walls are BPS if the singularity is resolved and non--BPS if it is deformed and fibered. We show that these domain walls may interpolate between vacua that support monopoles and/or vortices.
Radial vibrations of BPS skyrmions
Adam, C; Romanczukiewicz, T; Wereszczynski, A
2016-01-01
We study radial vibrations of spherically symmetric skyrmions in the BPS Skyrme model. Concretely, we numerically solve the linearised field equations for small fluctuations in a skyrmion background, both for linearly stable oscillations and for (unstable) resonances. This is complemented by numerical solutions of the full nonlinear system, which confirm all the results of the linear analysis. In all cases, the resulting fundamental excitation provides a rather accurate value for the Roper resonance, supporting the hypothesis that the BPS Skyrme model already gives a reasonable approximate description of this resonance.
Adam, C.; C. Naya; Sanchez-Guillen, J.; Wereszczynski, A.
2012-01-01
We analyze the vector meson formulation of the BPS Skyrme model in (3+1) dimensions, where the term of sixth power in first derivatives characteristic for the original, integrable BPS Skyrme model (the topological or baryon current squared) is replaced by a coupling between the vector meson $\\omega_\\mu$ and the baryon current. We find that the model remains integrable in the sense of generalized integrability and almost solvable (reducible to a set of two first order ODEs) for any value of th...
Gravitating BPS dyons witout a dilaton
Lee, C; Lee, Choonkyu; Park, Q Han
1996-01-01
We describe curved-space BPS dyon solutions, the ADM mass of which saturates the gravitational version of the Bogomol'nyi bound. This generalizes self-gravitating BPS monopole solutions of Gibbons et al. when there is no dilaton.
Adam, C; Sanchez-Guillen, J; Wereszczynski, A
2012-01-01
We analyze the vector meson formulation of the BPS Skyrme model in (3+1) dimensions, where the term of sixth power in first derivatives characteristic for the original, integrable BPS Skyrme model (the topological or baryon current squared) is replaced by a coupling between the vector meson $\\omega_\\mu$ and the baryon current. We find that the model remains integrable in the sense of generalized integrability and almost solvable (reducible to a set of two first order ODEs) for any value of the baryon charge. Further, we analyze the appearance of topological solitons for two one-parameter families of one vacuum potentials: the old Skyrme potentials and the so-called BPS potentials. Depending on the value of the parameters we find several qualitatively different possibilities. In the massless case we have a parameter region with no skyrmions, a unique compact skyrmion with a discontinuous first derivative at the boundary (equivalently, with a source term located at the boundary, which screens the topological ch...
BPS Skyrmions as neutron stars
Adam, C., E-mail: adam@fpaxp1.usc.es [Departamento de Física de Partículas, Universidad de Santiago de Compostela and Instituto Galego de Física de Altas Enerxias (IGFAE), E-15782 Santiago de Compostela (Spain); Naya, C.; Sanchez-Guillen, J.; Vazquez, R. [Departamento de Física de Partículas, Universidad de Santiago de Compostela and Instituto Galego de Física de Altas Enerxias (IGFAE), E-15782 Santiago de Compostela (Spain); Wereszczynski, A. [Institute of Physics, Jagiellonian University, Reymonta 4, Kraków (Poland)
2015-03-06
The BPS Skyrme model has been demonstrated already to provide a physically intriguing and quantitatively reliable description of nuclear matter. Indeed, the model has both the symmetries and the energy–momentum tensor of a perfect fluid, and thus represents a field theoretic realization of the “liquid droplet” model of nuclear matter. In addition, the classical soliton solutions together with some obvious corrections (spin–isospin quantization, Coulomb energy, proton-neutron mass difference) provide an accurate modeling of nuclear binding energies for heavier nuclei. These results lead to the rather natural proposal to try to describe also neutron stars by the BPS Skyrme model coupled to gravity. We find that the resulting self-gravitating BPS Skyrmions provide excellent results as well as some new perspectives for the description of bulk properties of neutron stars when the parameter values of the model are extracted from nuclear physics. Specifically, the maximum possible mass of a neutron star before black-hole formation sets in is a few solar masses, the precise value of which depends on the precise values of the model parameters, and the resulting neutron star radius is of the order of 10 km.
Theta Series, Wall-Crossing and Quantum Dilogarithm Identities
Alexandrov, Sergei; Pioline, Boris
2016-08-01
Motivated by mathematical structures which arise in string vacua and gauge theories with N=2 supersymmetry, we study the properties of certain generalized theta series which appear as Fourier coefficients of functions on a twisted torus. In Calabi-Yau string vacua, such theta series encode instanton corrections from k Neveu-Schwarz five-branes. The theta series are determined by vector-valued wave-functions, and in this work we obtain the transformation of these wave-functions induced by Kontsevich-Soibelman symplectomorphisms. This effectively provides a quantum version of these transformations, where the quantization parameter is inversely proportional to the five-brane charge k. Consistency with wall-crossing implies a new five-term relation for Faddeev's quantum dilogarithm {Φ_b} at b = 1, which we prove. By allowing the torus to be non-commutative, we obtain a more general five-term relation valid for arbitrary b and k, which may be relevant for the physics of five-branes at finite chemical potential for angular momentum.
Theta series, wall-crossing and quantum dilogarithm identities
Alexandrov, Sergei
2015-01-01
Motivated by mathematical structures which arise in string vacua and gauge theories with N=2 supersymmetry, we study the properties of certain generalized theta series which appear as Fourier coefficients of functions on a twisted torus. In Calabi-Yau string vacua, such theta series encode instanton corrections from $k$ Neveu-Schwarz five-branes. The theta series are determined by vector-valued wave-functions, and in this work we obtain the transformation of these wave-functions induced by Kontsevich-Soibelman symplectomorphisms. This effectively provides a quantum version of these transformations, where the quantization parameter is inversely proportional to the five-brane charge $k$. Consistency with wall-crossing implies a new five-term relation for Faddeev's quantum dilogarithm $\\Phi_b$ at $b=1$, which we prove. By allowing the torus to be non-commutative, we obtain a more general five-term relation valid for arbitrary $b$ and $k$, which may be relevant for the physics of five-branes at finite chemical po...
Wall Crossing Invariants: from quantum mechanics to knots
Galakhov, D; Morozov, A
2014-01-01
We offer a pedestrian level review of the wall-crossing invariants. The story begins from the scattering theory in quantum mechanics where the spectrum reshuffling can be related to permutations of S-matrices. In non-trivial situations, starting from spin chains and matrix models, the S-matrices are operator-valued and their algebra is described in terms of R- and mixing (Racah) U-matrices. Then, the Kontsevich-Soibelman invariants are nothing but the standard knot invariants made out of these data within the Reshetikhin-Turaev-Witten approach. The R- and Racah matrices acquire a relatively universal form in the quasiclassical limit, where the basic reshufflings with the change of moduli are those of the Stokes line. Natural from this point of view are matrices provided by the modular transformations of conformal blocks (with the usual identification R=T and U=S), and in the simplest case of the first degenerate field (2,1), when the conformal blocks satisfy a second order Shroedinger-like equation, the invar...
Theta Series, Wall-Crossing and Quantum Dilogarithm Identities
Alexandrov, Sergei; Pioline, Boris
2016-05-01
Motivated by mathematical structures which arise in string vacua and gauge theories with {{{N}=2}} supersymmetry, we study the properties of certain generalized theta series which appear as Fourier coefficients of functions on a twisted torus. In Calabi-Yau string vacua, such theta series encode instanton corrections from k Neveu-Schwarz five-branes. The theta series are determined by vector-valued wave-functions, and in this work we obtain the transformation of these wave-functions induced by Kontsevich-Soibelman symplectomorphisms. This effectively provides a quantum version of these transformations, where the quantization parameter is inversely proportional to the five-brane charge k. Consistency with wall-crossing implies a new five-term relation for Faddeev's quantum dilogarithm {Φ_b} at b = 1, which we prove. By allowing the torus to be non-commutative, we obtain a more general five-term relation valid for arbitrary b and k, which may be relevant for the physics of five-branes at finite chemical potential for angular momentum.
Multiply Phased Traveling BPS Vortex
Kimm, Kyoungtae; Cho, Y M
2016-01-01
We present the multiply phased current carrying vortex solutions in the U(1) gauge theory coupled to an $(N+1)$-component SU(N+1) scalar multiplet in the Bogomolny limit. Our vortex solutions correspond to the static vortex dressed with traveling waves along the axis of symmetry. What is notable in our vortex solutions is that the frequencies of traveling waves in each component of the scalar field can have different values. The energy of the static vortex is proportional to the topological charge of $CP^N$ model in the BPS limit, and the multiple phase of the vortex supplies additional energy contribution which is proportional to the Noether charge associated to the remaining symmetry.
Wenqi Yu
Full Text Available A fluorescence microscopy method to directly follow the localization of defined proteins in Staphylococcus was hampered by the unstable fluorescence of fluorescent proteins. Here, we constructed plasmid (pCX encoded red fluorescence (RF mCherry (mCh hybrids, namely mCh-cyto (no signal peptide and no sorting sequence, mCh-sec (with signal peptide, and mCh-cw (with signal peptide and cell wall sorting sequence. The S. aureus clones targeted mCh-fusion proteins into the cytosol, the supernatant and the cell envelope respectively; in all cases mCherry exhibited bright fluorescence. In staphylococci two types of signal peptides (SP can be distinguished: the +YSIRK motif SP(lip and the -YSIRK motif SP(sasF. mCh-hybrids supplied with the +YSIRK motif SP(lip were always expressed higher than those with -YSIRK motif SP(sasF. To study the location of the anchoring process and also the influence of SP type, mCh-cw was supplied on the one hand with +YSIRK motif (mCh-cw1 and the other hand with -YSIRK motif (mCh-cw2. MCh-cw1 preferentially localized at the cross wall, while mCh-cw2 preferentially localized at the peripheral wall. Interestingly, when treated with sub-lethal concentrations of penicillin or moenomycin, both mCh-cw1 and mCh-cw2 were concentrated at the cross wall. The shift from the peripheral wall to the cross wall required Sortase A (SrtA, as in the srtA mutant this effect was blunted. The effect is most likely due to antibiotic mediated increase of free anchoring sites (Lipid II at the cross wall, the substrate of SrtA, leading to a preferential incorporation of anchored proteins at the cross wall.
Analysis of moderately thin-walled beam cross-sections by cubic isoparametric elements
Høgsberg, Jan Becker; Krenk, Steen
2014-01-01
numerically by introducing a cubic-linear two-dimensional isoparametric element. The cubic interpolation of this element accurately represents quadratic shear stress variations along cross-section walls, and thus moderately thin-walled cross-sections are effectively discretized by these elements. The ability...... of this element to represent curved geometries, and to accurately determine cross-section parameters and shear stress distributions is demonstrated....
BPS Boojums in N=2 supersymmetric gauge theories
Arai, Masato; Eto, Minoru
2016-01-01
We study 1/4 Bogomol'nyi-Prasad-Sommerfield (BPS) composite solitons of vortex strings, domain walls and boojums in N=2 supersymmetric Abelian gauge theories in four dimensions. We obtain solutions to the 1/4 BPS equations with the finite gauge coupling constant. To obtain numerical solutions for generic coupling constants, we construct globally correct approximate functions which allow us to easily find fixed points of a gradient flow equations. We analytically/numerically confirm that the negative mass of a single boojum appearing at the end point of the vortex string on the logarithmically bent domain wall is equal to the half-mass of the 't Hooft-Polyakov monopole. We examine various configurations and clarify how the shape of the boojum depends on the coupling constants and moduli parameters. We find a semi-local boojum with a size moduli which appears when the semi-local string ends on the domain wall. We introduce a magnetic scalar potential which offers an intuitive understanding that the end point of...
We construct an infinite E9 multiplet of BPS states for 11D supergravity. For each positive real root of E9 we obtain a BPS solution of 11D supergravity, or of its exotic counterparts, depending on two non-compact transverse space variables. All these solutions are related by U-dualities realised via E9 Weyl transformations in the regular embedding E9-E10-E11. In this way we recover the basic BPS solutions, namely the KK-wave, the M2 brane, the M5 brane and the KK6-monopole, as well as other solutions admitting eight longitudinal space dimensions. A novel technique of combining Weyl reflexions with compensating transformations allows the construction of many new BPS solutions, each of which can be mapped to a solution of a dual effective action of gravity coupled to a certain higher rank tensor field not contained in 11D supergravity. For real roots of E10 which are not roots of E9, we obtain additional BPS solutions transcending 11D supergravity (as exemplified by the lowest level solution corresponding to the M9 brane). The relation between the dual formulation and the one in terms of the original 11D supergravity fields has significance beyond the realm of BPS solutions. We establish the link with the Geroch group of general relativity, and explain how the E9 duality transformations generalize the standard Hodge dualities to an infinite set of 'non-closing dualities'
In-vitro fermentability of cell walls as influenced by lignin composition and cross-linking.
We assessed how diverse modifications in lignin composition and reductions in ferulate-lignin cross-linking influence the degradability of cell walls. Cell walls from nonlignified maize cell suspensions were artificially lignified with varying ratios of normal monolignols (coniferyl and sinapyl alco...
Near BPS Skyrmions and Restricted Harmonic Maps
Speight, J M
2014-01-01
Motivated by a class of near BPS Skyrme models introduced by Adam, S\\'anchez-Guill\\'en and Wereszczy\\'nski, the following variant of the harmonic map problem is introduced: a map $\\phi:(M,g)\\rightarrow (N,h)$ between Riemannian manifolds is restricted harmonic (RH) if it locally extremizes $E_2$ on its $SDiff(M)$ orbit, where $SDiff(M)$ denotes the group of volume preserving diffeomorphisms of $(M,g)$, and $E_2$ denotes the Dirichlet energy. It is conjectured that near BPS skyrmions tend to RH maps in the BPS limit. It is shown that $\\phi$ is RH if and only if $\\phi^*h$ has exact divergence, and a linear stability theory of RH maps is developed, whence it follows that all weakly conformal maps, for example, are stable RH. Examples of RH maps in every degree class $R^3\\to SU(2)$ and $R^2\\to S^2$ are constructed. It is shown that the axially symmetric BPS skyrmions on which all previous analytic studies of near BPS Skyrme models have been based, are not RH, so each such field can be deformed along $SDiff(R^3)$ ...
Cho, Inyong; Kim, Yoonbai
2008-01-01
We investigate the BPS configuration of the multi D-vortices produced from the D2${\\bar {\\rm D}}$2 system. Based on the DBI-type action with a Gaussian-type runaway potential for a complex tachyon field, the BPS limit is achieved when the tachyon profile is thin. The solution states randomly-distributed $n$ static D-vortices with zero interaction. With the obtained BPS configuration, we derive the relativistic Lagrangian which describes the dynamics of free massive D-vortices. We also discuss the 90${}^{\\circ}$ and 180${}^{\\circ}$ scattering of two identical D-vortices, and present its implications on the reconnection in the dynamics of cosmic superstrings.
Near BPS skyrmions and restricted harmonic maps
Speight, J. M.
2015-06-01
Motivated by a class of near BPS Skyrme models introduced by Adam, Sánchez-Guillén and Wereszczyński, the following variant of the harmonic map problem is introduced: a map φ :(M, g) →(N, h) between Riemannian manifolds is restricted harmonic if it locally extremizes E2 on its SDiff(M) orbit, where SDiff(M) denotes the group of volume preserving diffeomorphisms of (M, g), and E2 denotes the Dirichlet energy. It is conjectured that near BPS skyrmions tend to restricted harmonic maps in the BPS limit. It is shown that φ is restricted harmonic if and only if φ∗ h has exact divergence, and a linear stability theory of restricted harmonic maps is developed, from which it follows that all weakly conformal maps are stable restricted harmonic. Examples of restricted harmonic maps in every degree class R3 → SU(2) and R2 →S2 are constructed. It is shown that the axially symmetric BPS skyrmions on which all previous analytic studies of near BPS Skyrme models have been based, are not restricted harmonic, casting doubt on the phenomenological predictions of such studies. The problem of minimizing E2 for φ :Rk → N over all linear volume preserving diffeomorphisms is solved explicitly, and a deformed axially symmetric family of Skyrme fields constructed which are candidates for approximate near BPS skyrmions at low baryon number. The notion of restricted harmonicity is generalized to restricted F-criticality where F is any functional on maps (M, g) →(N, h) which is, in a precise sense, geometrically natural. The case where F is a linear combination of E2 and E4, the usual Skyrme term, is studied in detail, and it is shown that inverse stereographic projection R3 →S3 ≡ SU(2) is stable restricted F-critical for every such F.
Bouncing universe and non-BPS branes
Loewenfeld, Philipp Höffer v.; Kang, Jin U.; Moeller, Nicolas; Sachs, Ivo
2009-01-01
We describe string frame bouncing universe scenarios involving the creation and annihilation of a non-BPS D9-brane in type IIA superstring theory. We find several classes of solutions, in which the bounce is driven by the tachyon dynamics of the non-BPS brane. The metric and the dilaton are consistently described in terms of the lowest order effective action. The bounce solutions interpolate between contracting and expanding pre-big bang (or post-big bang) solutions. The singular behavior of ...
BPS Electromagnetic Waves on Giant Gravitons
Kim, S; Kim, Seok; Lee, Kimyeong
2005-01-01
We find new 1/8-BPS giant graviton solutions in $AdS_5 \\times S^5$, carrying three angular momenta along $S^5$, and investigate their properties. Especially, we show that nonzero worldvolume gauge fields are admitted preserving supersymmetry. These gauge field modes can be viewed as electromagnetic waves along the compact D3 brane, whose Poynting vector contributes to the BPS angular momenta. We also analyze the (nearly-)spherical giant gravitons with worldvolume gauge fields in detail. Expressing the $S^3$ in Hopf fibration ($S^1$ fibred over $S^2$), the wave propagates along the $S^1$ fiber.
We present a candidate supergravity solution for a stacked configuration of stable non-BPS D-branes in Type II string theory compactified on T4/Z2. This gives a supergravity description of nonabelian tachyon condensation on the brane woldvolume. (author)
Quantification of cross-sectional artery wall motion with IVUS image registration
Oakeson, Kevin D.; Zhu, Hui; Friedman, Morton H.
2004-04-01
Atherosclerotic lesions have been shown to have different mechanical properties than the non-diseased artery. Calculating vessel wall strain from cross-sectional vessel wall motions allows for the measurement of local stiffness. In this paper, a robust method is developed to track cross-sectional displacements of an artery wall using two different intravascular ultrasound (IVUS) images acquired at two different pressure levels respectively. First, the vessel wall region in one image is segmented semi-automatically by refining two spline-based contours to the locations of inner and outer vessel wall borders. Then the ringlike wall region in one image is registered to its counterpart in the other image in polar coordinates. The registration is performed by minimizing an energy function of the 2D motion field based on a spline-deformable-model. Both intensity and gradient information of the images are used to construct the energy function so that an accurate registration can be achieved. Registration accuracy was tested on simulated motions using IVUS images of a human coronary artery and a porcine carotid. The wall displacement fields calculated from real motion images are also demonstrated.
A Low Cross-Polarization Smooth-Walled Horn with Improved Bandwidth
Zeng, Lingzhen; Bennett, Charles L.; Chuss, David T.; Wollack, Edward J.
2009-01-01
Corrugated feed horns offer excellent beam symmetry, main beam efficiency, and cross-polar response over wide bandwidths, but can be challenging to fabricate. An easier-to-manufacture smooth-walled feed is explored that approximates these properties over a finite bandwidth. The design, optimization and measurement of a monotonically-profiled, smooth-walled scalar feedhorn with a diffraction-limited approximately 7 degrees full width at half maximum (FWHM) is presented. The feed was demonstrated to have low cross polarization (<-30 dB) across the frequency range 33-45 GHz (30% fractional bandwidth). A return loss better than -28 dB was measured across the band.
Van, Nguyen Dang; Ihn, Namgung [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)
2014-10-15
The ununiformed deformation of cross section of bent tube also occurs, which is not perfectly circular and uniform but a significant ovality can result in from the fabrication process. In this study, an investigation of the deformation profile of bent tube such as wall thickening/thinning and cross-sectional distortion in cold bending process will be performed. The finite element model, using ANSYS 14.5, is developed and simulated the bending process. The results will be investigated for any change of diameter and circularity perpendicular to the bending axis. The analyses showed that the change of wall thickness of tube will happen in bending process. Consequently, the bend region of tube appears thicker wall at intrados and thinner wall at extrados. Moreover, bending process affects the ovality of tube cross section at bend region. From these results, wall thinning and cross-sectional ovality change need to be considered in the application and design of tube. In case of ICI guide tube, the inner circularity very important since ICI probe has to pass through the bend elbow, and any deviation from the tolerance causes stuck of ICI probe in the bend region. This is one of the particular applications where geometric deviations need to be carefully monitored. In fluid application of tube, the thinning is more of concern than the ovality of cross section. Hence there is also limit on how much wall thinning be allowed. The simulation presented in this paper is focused on the estimation of geometric variation resulted in bending process of tube with typical bending process.
A note on multiply wound BPS Wilson loops in ABJM
Bianchi, Marco S.
2016-01-01
We consider BPS Wilson loops in planar ABJM theory, wound multiple times around the great circle. We compute the expectation value of the 1/6-BPS and 1/2-BPS Wilson loops to three- and two-loop order in perturbation theory, respectively, dealing with the combinatorics of multiple winding via recursive relations. For the 1/6-BPS Wilson loop we perform the computation at generic framing and at framing 1 we find agreement with the localization result. For the 1/2-BPS Wilson loop we compute the e...
Wall-crossing, Rogers dilogarithm, and the QK/HK correspondence
Alexandrov, Sergei; Pioline, Boris
2011-01-01
When formulated in twistor space, the D-instanton corrected hypermultiplet moduli space in N=2 string vacua and the Coulomb branch of rigid N=2 gauge theories on $R^3 \\times S^1$ are strikingly similar and, to a large extent, dictated by consistency with wall-crossing. We elucidate this similarity by showing that these two spaces are related under a general duality between, on one hand, quaternion-Kahler manifolds with a quaternionic isometry and, on the other hand, hyperkahler manifolds with a rotational isometry, further equipped with a hyperholomorphic circle bundle with a connection. We show that the transition functions of the hyperholomorphic circle bundle relevant for the hypermultiplet moduli space are given by the Rogers dilogarithm function, and that consistency across walls of marginal stability is ensured by the motivic wall-crossing formula of Kontsevich and Soibelman. We illustrate the construction on some simple examples of wall-crossing related to cluster algebras for rank 2 Dynkin quivers. In...
Pressure field in flow through uniform straight pipes with varying wall cross curvature.
Naili, Salah; Thiriet, Marc
2005-10-01
Pressure fields in rigid smooth straight tubes with an axially uniform cross section, in which an incompressible Newtonian fluid flows steadily, have been determined. Five cross section shapes are used. The reference cross section S0 is slightly elliptic (ellipticity of 1.005). Four cross section shapes, which mimic collapsed vessels in an uniformly frozen state, are defined according to the curvature of their opposite faces (the mid-face is located on the minor axis) Sq (parallel faces), St (face folding), Sc (point contact between faces) and Sl (line contact). These four selected cross shapes are characterized by large changes in both the cross sectional shape and area with respect to S0. The cross shapes are obtained from the computation of the deformation under uniform transmural pressures, without extension, of a thin-walled conduit of infinite length and of homogeneous purely elastic walls of constant thickness. The Navier-Stokes equations are solved using the finite element method for the five tubes summation operator0, summation operatorq, summation operatort, summation operatorc and summation operatorl, which are associated with S0,Sq,St,Sc and Sl, respectively. The numerical tests are performed with the same value of the volume flow rate whatever the tube configuration for three Reynolds numbers ( [See text] ). The present work is aimed at studying the pressure field for the design of the flow chamber in which endothelial cells are cultured. This field is used not only to define a new relative pressure index to determine the entry length but also to estimate the wall shear stress when the flow is fully developed. PMID:16124988
Baby Skyrme Model, Near-BPS Approximations and Supersymmetric Extensions
Bolognesi, S.; Zakrzewski, W.
2014-01-01
We study the baby Skyrme model as a theory that interpolates between two distinct BPS systems. For this a near-BPS approximation can be used which, however, involves a small deviation from each of the two BPS limits. We provide analytical explanation and numerical support for the validity of this approximation. We then study the set of all possible supersymmetric extensions of the baby Skyrme model with ${\\cal N}=1$ and the particular ones with extended ${\\cal N}=2$ supersymmetries and relate...
Baby Skyrme model, near-BPS approximations, and supersymmetric extensions
Bolognesi, S.; Zakrzewski, W.
2015-02-01
We study the baby Skyrme model as a theory that interpolates between two distinct BPS systems. For this, a near-BPS approximation can be used when there is a small deviation from each of the two BPS limits. We provide analytical explanation and numerical support for the validity of this approximation. We then study the set of all possible supersymmetric extensions of the baby Skyrme model with N =1 and the particular ones with extended N =2 supersymmetries and relate this to the above mentioned almost-BPS approximation.
Baby Skyrme Model, Near-BPS Approximations and Supersymmetric Extensions
Bolognesi, S
2014-01-01
We study the baby Skyrme model as a theory that interpolates between two distinct BPS systems. For this a near-BPS approximation can be used which, however, involves a small deviation from each of the two BPS limits. We provide analytical explanation and numerical support for the validity of this approximation. We then study the set of all possible supersymmetric extensions of the baby Skyrme model with ${\\cal N}=1$ and the particular ones with extended ${\\cal N}=2$ supersymmetries and relate this to the above mentioned almost-BPS approximation.
Level crossings, excess times and transient plasma-wall interactions in fusion plasmas
Theodorsen, Audun
2016-01-01
Based on a stochastic model for intermittent fluctuations in the boundary region of magnetically confined plasmas, an expression for the level crossing rate is derived from the joint distribution of the process and its derivative. From this the average time spent by the process above a certain threshold level is obtained. This provides novel predictions of plasma-wall interactions due to transient transport events associated with radial motion of blob-like structures in the scrape-off layer.
Sati, Hisham
2015-01-01
We uncover higher algebraic structures on Noether currents and BPS charges. It is known that equivalence classes of conserved currents form a Lie algebra. We show that at least for target space symmetries of higher parameterized WZW-type sigma-models this naturally lifts to a Lie (p+1)-algebra structure on the Noether currents themselves. Applied to the Green-Schwarz-type action functionals for super p-brane sigma-models this yields super Lie (p+1)-algebra refinements of the traditional BPS brane charge extensions of supersymmetry algebras. We discuss this in the generality of higher differential geometry, where it applies also to branes with (higher) gauge fields on their worldvolume. Applied to the M5-brane sigma-model we recover and properly globalize the M-theory super Lie algebra extension of 11-dimensional superisometries by 2-brane and 5-brane charges. Passing beyond the infinitesimal Lie theory we find cohomological corrections to these charges in higher analogy to the familiar corrections for D-brane...
The Skyrme model in the BPS limit
Adam, C; Sanchez-Guillen, J; Vazquez, R; Wereszczynski, A
2015-01-01
In this review, we summarise the main features of the BPS Skyrme model which provides a physically well-motivated idealisation of atomic nuclei and nuclear matter: 1) it leads to zero binding energies for classical solitons (while realistic binding energies emerge owing to the semiclassical corrections, the Coulomb interaction and isospin breaking); 2) it describes a perfect non-barotropic fluid already at the microscopic (field theoretical) level which allows to study thermodynamics beyond the mean-field limit. These properties allow for an approximate but analytical calculation of binding energies of the most abundant nuclei, for a determination of the equation of state of skyrmionic matter (both in the full field theory and in a mean-field approximation) as well as the description of neutron stars as Skyrme solitons with a very good agreement with available observational data. All these results suggest that the proper low energy effective model of QCD should be close to the BPS Skyrme model in a certain se...
THIN-WALLED CROSS SECTION SHAPE INFLUENCE ON STEEL MEMBER RESISTANCE
Elżbieta Urbańska-Galewska
2016-03-01
Full Text Available This work describes why trending thin-walled technology is achieving popularity in steel construction sector. A purpose of this article is to present the influence of the cold-formed element cross-section shape on an axial compression and a bending moment resistance. The authors have considered four different shapes assuming constant section area and thickness. Calculations were based on three different steel grades taking into account local, distortional and overall buckling. The results are presented in a tabular and a graphical way and clearly confirm that cross-section forming distinctly impact the cold-formed member resistance. The authors choose these cross-sections that work better in compression state and the other (those slender and high that function more efficiently are subjected to bending.
A note on multiply wound BPS Wilson loops in ABJM
Bianchi, Marco S
2016-01-01
We consider BPS Wilson loops in planar ABJM theory, wound multiple times around the great circle. We compute the expectation value of the 1/6-BPS and 1/2-BPS Wilson loops to three- and two-loop order in perturbation theory, respectively, dealing with the combinatorics of multiple winding via recursive relations. For the 1/6-BPS Wilson loop we perform the computation at generic framing and at framing 1 we find agreement with the localization result. For the 1/2-BPS Wilson loop we compute the expectation value at trivial framing and by comparison with the matrix model expression we extract the framing dependence of the fermion diagrams.
BPS counting for knots and combinatorics on words
Kucharski, Piotr
2016-01-01
We discuss relations between quantum BPS invariants defined in terms of a product decomposition of certain series, and difference equations (quantum A-polynomials) that annihilate such series. We construct combinatorial models whose structure is encoded in the form of such difference equations, and whose generating functions (Hilbert-Poincar\\'e series) are solutions to those equations and reproduce generating series that encode BPS invariants. Furthermore, BPS invariants in question are expressed in terms of Lyndon words in an appropriate language, thereby relating counting of BPS states to the branch of mathematics referred to as combinatorics on words. We illustrate these results in the framework of colored extremal knot polynomials: among others we determine dual quantum extremal A-polynomials for various knots, present associated combinatorial models, find corresponding BPS invariants (extremal Labastida-Mari\\~no-Ooguri-Vafa invariants) and discuss their integrality.
BACKGROUND: We used a biomimetic model system to ascertain how reductions in ferulate-lignin cross-linking and shifts in lignin composition influence ruminal cell wall fermentation. Primary walls from maize cell suspensions with normal or reduced feruloylation were artificially lignified with variou...
Perturbative type II amplitudes for BPS interactions
Basu, Anirban
2015-01-01
We consider the perturbative contributions to the R^4, D^4 R^4 and D^6 R^4 interactions in toroidally compactified type II string theory. These BPS interactions do not receive perturbative contributions beyond genus three. We derive Poisson equations satisfied by these moduli dependent string amplitudes. These T--duality invariant equations have eigenvalues that are completely determined by the structure of the integrands of the multi--loop amplitudes. The source terms are given by boundary terms of the moduli space of Riemann surfaces corresponding to both separating and non--separating nodes. These are determined directly from the string amplitudes, as well as from the logarithmic divergences of maximal supergravity. We explicitly solve these Poisson equations in nine and eight dimensions.
Superconformal Index, BPS Monodromy and Chiral Algebras
Cecotti, Sergio; Vafa, Cumrun; Yan, Wenbin
2015-01-01
We show that specializations of the 4d $\\mathcal{N}=2$ superconformal index labeled by an integer $N$ is given by $\\textrm{Tr}\\,{\\cal M}^N$ where ${\\cal M}$ is the Kontsevich-Soibelman monodromy operator for BPS states on the Coulomb branch. We provide evidence that the states enumerated by these limits of the index lead to a family of 2d chiral algebras $\\mathcal{A}_{N}$. This generalizes the recent results for the $N=-1$ case which corresponds to the Schur limit of the superconformal index. We show that this specialization of the index leads to the same integrand as that of the elliptic genus of compactification of the superconformal theory on $S^2\\times T^2$ where we turn on $\\frac{1}{2} N$ units of $U(1)_r$ flux on $S^2$.
Conover, Matt S.; Redfern, Crystal J.; Ganguly, Tridib; Sukumar, Neelima; Sloan, Gina; Mishra, Meenu; Deora, Rajendar
2012-01-01
Bordetella bacteria are Gram-negative respiratory pathogens of animals, birds, and humans. A hallmark feature of some Bordetella species is their ability to efficiently survive in the respiratory tract even after vaccination. Bordetella bronchiseptica and Bordetella pertussis form biofilms on abiotic surfaces and in the mouse respiratory tract. The Bps exopolysaccharide is one of the critical determinants for biofilm formation and the survival of Bordetella in the murine respiratory tract. In...
Time-resolved magnetization dynamics of cross-tie domain walls in permalloy microstructures
Miguel, J; Kurde, J; Piantek, M; Kuch, W [Institut fuer Experimentalphysik, Freie Universitaet Berlin, Arnimallee 14, D-14195 Berlin (Germany); Sanchez-Barriga, J; Heitkamp, B; Kronast, F; Duerr, H A [Helmholtz-Zentrum Berlin fuer Materialien und Energie, Elektronenspeicherring BESSY II, Albert-Einstein-Strasse 15, D-12489 Berlin (Germany); Bayer, D; Aeschlimann, M, E-mail: jorge.miguel@fu-berlin.d [Fachbereich Physik, Universitaet Kaiserslautern, Erwin-Schroedinger Strasse 46, D-67663 Kaiserslautern (Germany)
2009-12-02
We report on a picosecond time-resolved x-ray magnetic circular dichroic-photoelectron emission microscopy study of the evolution of the magnetization components of a microstructured permalloy platelet comprising three cross-tie domain walls. A laser-excited photoswitch has been used to apply a triangular 80 Oe, 160 ps magnetic pulse. Micromagnetic calculations agree well with the experimental results, both in time and frequency, illustrating the large angle precession in the magnetic domains with magnetization perpendicular to the applied pulse, and showing how the magnetic vortices revert their core magnetization while the antivortices remain unaffected.
BPS black holes in gauged N = 4, D = 4 supergravity
We find solutions of the bosonic sector of gauged N = 4, D = 4 SU(2) x SU(2) supergravity, which represent dilaton black holes with toroidal or spherical event horizons. The axion is consistently truncated, and the gauge group is broken to U(1) x U(1). The spherical black holes carry two electric and two magnetic abelian charges, whereas the toroidal holes have vanishing magnetic charges. The space-time metrics are warped products, and the manifolds turn out to be globally hyperbolic, in contrast to standard gauged supergravity ground states. It is shown that in the toroidal case, there are solutions preserving one quarter or one half of the supersymmetries, while for spherical topologies all supersymmetries are broken. In general, the toroidal BPS states represent naked singularities, but there is also a supersymmetric black hole with vanishing Hawking temperature. The ((1)/(2)) supersymmetric case arises for vanishing charges and mass, and represents the known domain wall solution of the Freedman-Schwarz model. It provides the background in which the black holes live. Finally, we use Chamseddine's and Volkov's Kaluza-Klein interpretation of gauged N = 4, D = 4 SU(2) x SU(2) supergravity to lift our solutions to ten and eleven dimensions and to consider them as solutions to the leading order equations of motion of the string/M-theory effective action
Thin-Walled Cross-Linked Acetabular Liners Need Not Exhibit Reduced Locking Strength.
Murtha, Andrew S; Roy, Marcel E; Whiteside, Leo A; Tilden, David S; Schmitt, Krystal L
2015-08-01
Use of larger diameter femoral heads has emerged as a promising strategy to reduce the risk of dislocation after total hip arthroplasty, but thinning the walls of cross-linked ultra-high-molecular-weight polyethylene (UHMWPE) acetabular liners to accommodate these larger heads may compromise the locking mechanism of the liner. The purpose of this study was to test the mechanical integrity of the locking mechanism in cross-linked and re-melted UHMWPE acetabular components with reduced wall thickness. The locking mechanism of cross-linked (100 kGy/re-melted) acetabular liners in sizes 50/28, 50/36, and 52/36 mm of 1 design was evaluated by lever-out tests and torsion tests. Torsion tests were performed at 2 angles to isolate the liner's locking tabs independent of the contribution of its central post. Lever-out testing demonstrated nominally reduced failure strength in 50/36-mm liners (13.3 N · m) compared with 50/28-mm liners (12.3 N · m; P=.0502), whereas the lever-out strength of 52/36-mm liners was 12.2±0.94 N · m. Failure torques were similar between 50/28- and 50/36-mm liners at 45° and 90°, but the failure torque of size 52/36-mm liners was significantly higher at each angle. The use of larger diameter femoral heads does not compromise the locking mechanism of thinned MicroSeal (Signal Medical Corp, Marysville, Michigan) acetabular liners. Use of a cross-linked UHMWPE acetabular liner, with a locking mechanism that is not compromised when the liner is thinned to a thickness of at least 2.86 mm, appears to be a biomechanically sound construct when articulated with large diameter femoral heads. PMID:26270761
Near BPS Wilson Loop in beta-deformed Theories
Chu, Chong-Sun; Giataganas, Dimitrios
2007-01-01
We propose a definition of the Wilson loop operator in the N=1 beta-deformed supersymmetric Yang-Mills theory. Although the operator is not BPS, it has a finite expectation value at least up to order (g^2 N)^2. This does not happen generally for a generic non-BPS Wilson loop whose expectation value is UV divergent. For this reason we call this a near-BPS Wilson loop and conjecture that its exact expectation value is finite. We derive the general form of the boundary condition satisfied by the...
1/2 BPS geometries of M2 giant gravitons
We construct the general 1/2 BPS M2 giant graviton solutions asymptotic to the 11-dimensional maximally supersymmetric plane-wave background, based on the recent work of Lin, Lunin, and Maldacena. The solutions have null singularity and we argue that it is unavoidable to have null singularity in the proposed framework, although the solutions are still physically relevant. They involve an arbitrary function F(x) which is shown to have a correspondence to the 1/2 BPS states of the Berenstein-Maldacena-Nastase (BMN) matrix model. A detailed map between the 1/2 BPS states of both sides is worked out
Geometric realizations of BPS states in N=2 theories
We study the BPS spectrum of the theory on a D3-brane probe in F-theory. The BPS states are realized by multi-string configurations in space-time. Only certain configurations obeying a selection rule give rise to BPS states in the four-dimensional probe theory. Using these string configurations, we determine the spectrum of N=2 SU(2) Yang-Mills. We also explore the relation between multi-string configurations, M-theory membranes and self-dual strings. (orig.)
No fermionic wigs for BPS attractors in 5 dimensions
Gentile, Lorenzo G.C., E-mail: lgentile@pd.infn.it [DISIT, Università del Piemonte Orientale, via T. Michel, 11, Alessandria I-15120 (Italy); Dipartimento di Fisica “Galileo Galilei”, Università di Padova, via Marzolo 8, I-35131 Padova (Italy); INFN, Sezione di Padova, via Marzolo 8, I-35131 Padova (Italy); Grassi, Pietro A., E-mail: pgrassi@mfn.unipmn.it [DISIT, Università del Piemonte Orientale, via T. Michel, 11, Alessandria I-15120 (Italy); INFN – Gruppo Collegato di Alessandria – Sezione di Torino (Italy); Marrani, Alessio, E-mail: alessio.marrani@fys.kuleuven.be [Instituut voor Theoretische Fysica, KU Leuven, Celestijnenlaan 200D, B-3001 Leuven (Belgium); Mezzalira, Andrea, E-mail: andrea.mezzalira@ulb.ac.be [Physique Théorique et Mathématique, Université Libre de Bruxelles, C.P. 231, B-1050 Bruxelles (Belgium); Sabra, Wafic A., E-mail: ws00@aub.edu.lb [Centre for Advanced Mathematical Sciences and Physics Department, American University of Beirut (Lebanon)
2014-07-30
We analyze the fermionic wigging of 1/2-BPS (electric) extremal black hole attractors in N=2, D=5 ungauged Maxwell–Einstein supergravity theories, by exploiting anti-Killing spinors supersymmetry transformations. Regardless of the specific data of the real special geometry of the manifold defining the scalars of the vector multiplets, and differently from the D=4 case, we find that there are no corrections for the near-horizon attractor value of the scalar fields; an analogous result also holds for 1/2-BPS (magnetic) extremal black string. Thus, the attractor mechanism receives no fermionic corrections in D=5 (at least in the BPS sector)
1/2 BPS Geometries of M2 Giant Gravitons
Bak, D; Yee, H U; Bak, Dongsu; Siwach, Sanjay; Yee, Ho-Ung
2005-01-01
We construct the general 1/2 BPS M2 giant graviton solutions asymptotic to the eleven-dimensional maximally supersymmetric plane wave background, based on the recent work of Lin, Lunin and Maldacena. The solutions have null singularity and we argue that it is unavoidable to have null singularity in the proposed framework, although the solutions are still physically relevant. They involve an arbitrary function F(x) which is shown to have a correspondence to the 1/2 BPS states of the BMN matrix model. A detailed map between the 1/2 BPS states of both sides is worked out.
Monstrous BPS-Algebras and the Superstring Origin of Moonshine
Paquette, Natalie M; Volpato, Roberto
2016-01-01
We provide a physics derivation of Monstrous moonshine. We show that the McKay-Thompson series $T_g$, $g\\in \\mathbb{M}$, can be interpreted as supersymmetric indices counting spacetime BPS-states in certain heterotic string models. The invariance groups of these series arise naturally as spacetime T-duality groups and their genus zero property descends from the behaviour of these heterotic models in suitable decompactification limits. We also show that the space of BPS-states forms a module for the Monstrous Lie algebras $\\mathfrak{m}_g$, constructed by Borcherds and Carnahan. We argue that $\\mathfrak{m}_g$ arise in the heterotic models as algebras of spontaneously broken gauge symmetries, whose generators are in exact correspondence with BPS-states. This gives $\\mathfrak{m}_g$ an interpretation as a kind of BPS-algebra.
Cosmic microwave anisotropies from BPS semilocal strings
Urrestilla, Jon; Hindmarsh, Mark; Kunz, Martin; Liddle, Andrew R
2007-01-01
We present the first ever calculation of cosmic microwave background CMB anisotropy power spectra from semilocal cosmic strings, obtained via simulations of a classical field theory. Semilocal strings are a type of non-topological defect arising in some models of inflation motivated by fundamental physics, and are thought to relax the constraints on the symmetry breaking scale as compared to models with (topological) cosmic strings. We derive constraints on the model parameters, including the string tension parameter mu, from fits to cosmological data, and find that in this regard BPS semilocal strings resemble textures more than topological strings. The observed microwave anisotropy at l=10 is reproduced if Gmu = 4.9x10^{-6} (G is Newton's constant). However as with other defects the spectral shape does not match observations, and in models with inflationary perturbations plus semilocal strings the 95% confidence level upper bound is Gmu<1.9x10^{-6} when CMB data, Hubble Key Project and Big Bang Nucleosyn...
IDENTIFYING GENES CONTROLLING FERULATE CROSS-LINKING FORMATION IN GRASS CELL WALLS
de O Buanafina, Marcia Maria
2013-10-16
DESCRIPTION/ABSTRACT This proposal focuses on cell wall feruloylation and our long term goal is to identify and isolate novel genes controlling feruloylation and to characterize the phenotype of mutants in this pathway, with a spotlight on cell wall properties. Currently, the genes underlying AX feruloylation have not been identified and the isolation of such genes could be of great importance in manipulating ferulates accretion to the wall. Mutation of the feruloyl transferase gene(s) should lead to less ferulates secreted to the cell wall and reduced ferulate cross-linking. Our current research is based on the hypothesis that controlling the level of total feruloylation will have a direct impact on the level of cross-linking and in turn impact biomass utility for forage and biofuel production. Our results/accomplishments for this project so far include: 1. Mutagenised Brachypodium population. We have developed EMS mutagenized populations of model grass species Brachypodium distachyon. EMS populations have been developed from over 28,000 mutagenized seeds generating 5,184 M2 families. A total of 20,793 plants have been screened and 1,233 were originally selected. 2. Selected Brachypodium mutants: Potential mutants on their levels of cell wall ferulates and cell wall AX ? have been selected from 708 M2 families. A total of 303 back-crosses to no-mutagenized parental stock have been done, followed by selfing selected genotypes in order to confirm heritability of traits and to remove extraneous mutations generated by EMS mutagenesis. We are currently growing 12 F5 and F6 populations in order to assess CW composition. If low level of ferulates are confirmed in the candidate lines selected the mutation could be altered in different in one or several kinds of genes such as genes encoding an AX feruloyl transferase; genes encoding the arabinosyl transferase; genes encoding the synthesis of the xylan backbone; genes encoding enzymes of the monolignol pathway affecting FA
Large N BPS states and emergent quantum gravity
Berenstein, David
2006-01-01
This paper provides a heuristic derivation of how classical gravitational physics in the AdS/CFT correspondence appears from the strong dynamics of the Script N = 4 SYM theory in a systematic way. We do this in a minisuperspace approximation by studying 1/8 BPS configurations. We can show that our description matches the semiclassical physics of 1/8 BPS states in supergravity. We also provide a heuristic description of how massive strings appear in the geometry, and how at strong 't Hooft coupling they become local on the S5 suggesting that they can be realized as a sigma model on a weakly curved background. We show that the dynamics of 1/8 BPS dynamics of Script N = 4 SYM on a round S3 can be reduced to that of a matrix model for commuting matrices. Including measure factors, we show that this effective dynamics is related to bosons living on a six dimensional phase space with repulsive interactions. Because of these interactions, we can argue that on the ground state the bosons assemble themselves on a spherical shell in the shape of a round five sphere. This sphere will be identified with the S5 in the AdS dual geometry. To do this, we first define a precise way to coarse grain the dynamics. We use half BPS configurations as a toy model for this coarse graining, and we can reproduce the droplet picture of these half BPS states systematically. The droplet appears as the saddle point approximation of a statistical ensemble related to the square of the wave function of the eigenvalues of a complex matrix. This procedure is also applied to the set of 1/8 BPS configurations to extract the geometry, giving an analog of the droplet picture of half BPS states for the case of 1/8 BPS configurations. We also have a conjectured realization of some 1/8 BPS giant graviton wave functions in the dynamics, which captures all 1/8 BPS giant gravitons constructed by Mikhailov. This leads to a lot of different topology changes which can be treated heuristically.
Arroyo, Javier; Farkaš, Vladimír; Sanz, Ana Belén; Cabib, Enrico
2016-09-01
The cross-linking of polysaccharides to assemble new cell wall in fungi requires transglycosylation mechanisms by which preexisting glycosidic linkages are broken and new linkages are created between the polysaccharides. The molecular mechanisms for these processes, which are essential for fungal cell biology, are only now beginning to be elucidated. Recent development of in vivo and in vitro biochemical approaches has allowed characterization of important aspects about the formation of chitin-glucan covalent cell wall cross-links by cell wall transglycosylases of the CRH family and their biological function. Covalent linkages between chitin and glucan mediated by Crh proteins control morphogenesis and also play important roles in the remodeling of the fungal cell wall as part of the compensatory responses necessary to counterbalance cell wall stress. These enzymes are encoded by multigene families of redundant proteins very well conserved in fungal genomes but absent in mammalian cells. Understanding the molecular basis of fungal adaptation to cell wall stress through these and other cell wall remodeling enzymatic activities offers an opportunity to explore novel antifungal treatments and to identify potential fungal virulence factors. PMID:27185288
Irshad Kashif
2016-01-01
Full Text Available Maintaining indoor climatic conditions of buildings compatible with the occupant comfort by consuming minimum energy, especially in a tropical climate becomes a challenging problem for researchers. This paper aims to investigate this problem by evaluating the effect of different kind of Photovoltaic Trombe wall system (PV-TW on thermal comfort, energy consumption and CO2 emission. A detailed simulation model of a single room building integrated with PV-TW was modelled using TRNSYS software. Results show that 14-35% PMV index and 26-38% PPD index reduces as system shifted from SPV-TW to DGPV-TW as compared to normal buildings. Thermal comfort indexes (PMV and PPD lie in the recommended range of ASHARE for both DPV-TW and DGPV-TW except for the few months when RH%, solar radiation intensity and ambient temperature were high. Moreover PVTW system significantly reduces energy consumption and CO2 emission of the building and also 2-4.8 °C of temperature differences between indoor and outdoor climate of building was examined.
BPS Wilson loops in Minkowski spacetime and Euclidean space
Ouyang, Hao; Wu, Jun-Bao; Zhang, Jia-ju [Chinese Academy of Sciences, Theoretical Physics Division, Institute of High Energy Physics, Beijing (China); Chinese Academy of Sciences, Theoretical Physics Center for Science Facilities, Beijing (China)
2015-12-15
We give evidence that spacelike BPS Wilson loops do not exist in Minkowski spacetime. We show that spacelikeWilson loops in Minkowski spacetime cannot preserve any supersymmetries, in d = 4 N = 4 super Yang-Mills theory, d = 3 N = 2 super Chern-Simons-matter theory, and d = 3 N = 6 Aharony-Bergman-Jafferis- Maldacena theory. We not only show this using infinite straight lines and circles as examples, but also we give proofs for general curves. We attribute this to the conflicts of the reality conditions of the spinors. However, spacelike Wilson loops do exist in Euclidean space. There are both BPS Wilson loops along infinite straight lines and circular BPS Wilson loops. This is because the reality conditions of the spinors are lost after Wick rotation. The result is reasonable in view of the AdS/CFT correspondence. (orig.)
BPS Wilson loops in Minkowski spacetime and Euclidean space
Ouyang, Hao; Wu, Jun-Bao; Zhang, Jia-ju
2015-12-01
We give evidence that spacelike BPS Wilson loops do not exist in Minkowski spacetime. We show that spacelike Wilson loops in Minkowski spacetime cannot preserve any supersymmetries, in d = 4 N = 4 super Yang-Mills theory, d = 3 N = 2 super Chern-Simons-matter theory, and d = 3 N = 6 Aharony-Bergman-Jafferis-Maldacena theory. We not only show this using infinite straight lines and circles as examples, but also we give proofs for general curves. We attribute this to the conflicts of the reality conditions of the spinors. However, spacelike Wilson loops do exist in Euclidean space. There are both BPS Wilson loops along infinite straight lines and circular BPS Wilson loops. This is because the reality conditions of the spinors are lost after Wick rotation. The result is reasonable in view of the AdS/CFT correspondence.
Intravesical liposome drug delivery and IC/BPS
Janicki, Joseph J.; Gruber, Michele A.
2015-01-01
Intravesical therapy has previously shown to be effective in delaying or preventing recurrence of superficial bladder cancer. This local route of drug administration is now demonstrating promise in the treatment of interstitial cystitis/bladder pain syndrome (IC/BPS) with the benefit of minimal systemic side effects. Liposomes (LPs) are lipid vesicles composed of phospholipid bilayers surrounding an aqueous core. They can incorporate drug molecules, both hydrophobic and hydrophilic, and vastly improve cellular uptake of these drug molecules via endocytosis. Intravesical LPs have therapeutic effects on IC/BPS patients, mainly due to their ability to form a protective lipid film on the urothelial surface and repair the damaged urothelium. This review considers the current status of intravesical LPs and LP mediated drug delivery for the treatment of IC/BPS. PMID:26816855
BPS Wilson loops in Minkowski spacetime and Euclidean space
Ouyang, Hao, E-mail: ouyangh@ihep.ac.cn; Wu, Jun-Bao, E-mail: wujb@ihep.ac.cn; Zhang, Jia-ju, E-mail: jjzhang@ihep.ac.cn [Theoretical Physics Division, Institute of High Energy Physics, Chinese Academy of Sciences, 19B Yuquan Rd, 100049, Beijing (China); Theoretical Physics Center for Science Facilities, Chinese Academy of Sciences, 19B Yuquan Rd, 100049, Beijing (China)
2015-12-21
We give evidence that spacelike BPS Wilson loops do not exist in Minkowski spacetime. We show that spacelike Wilson loops in Minkowski spacetime cannot preserve any supersymmetries, in d=4N=4 super Yang–Mills theory, d=3N=2 super Chern–Simons-matter theory, and d=3N=6 Aharony–Bergman–Jafferis–Maldacena theory. We not only show this using infinite straight lines and circles as examples, but also we give proofs for general curves. We attribute this to the conflicts of the reality conditions of the spinors. However, spacelike Wilson loops do exist in Euclidean space. There are both BPS Wilson loops along infinite straight lines and circular BPS Wilson loops. This is because the reality conditions of the spinors are lost after Wick rotation. The result is reasonable in view of the AdS/CFT correspondence.
Some aspects of self-duality and generalised BPS theories
Adam, C.; Ferreira, L. A.; da Hora, E.; Wereszczynski, A.; Zakrzewski, W. J.
2013-08-01
If a scalar field theory in (1+1) dimensions possesses soliton solutions obeying first order BPS equations, then, in general, it is possible to find an infinite number of related field theories with BPS solitons which obey closely related BPS equations. We point out that this fact may be understood as a simple consequence of an appropriately generalised notion of self-duality. We show that this self-duality framework enables us to generalize to higher dimensions the construction of new solitons from already known solutions. By performing simple field transformations our procedure allows us to relate solitons with different topological properties. We present several interesting examples of such solitons in two and three dimensions.
Some aspects of self-duality and generalised BPS theories
Adam, C; da Hora, E; Wereszczynski, A; Zakrzewski, W J
2013-01-01
If a scalar field theory in (1+1) dimensions possesses soliton solutions obeying first order BPS equations, then, in general, it is possible to find an infinite number of related field theories with BPS solitons which obey closely related BPS equations. We point out that this fact may be understood as a simple consequence of an appropriately generalised notion of self-duality. We show that this self-duality framework enables us to generalize to higher dimensions the construction of new solitons from already known solutions. By performing simple field transformations our procedure allows us to relate solitons with different topological properties. We present several interesting examples of such solitons in two and three dimensions.
Abelianization of BPS quivers and the refined Higgs index
We count Higgs “phase” BPS states of general non-Abelian quiver, possibly with loops, by mapping the problem to its Abelian, or toric, counterpart and imposing Weyl invariance later. Precise Higgs index computation is particularly important for quivers with superpotentials; the Coulomb “phase” index is recently shown to miss important BPS states, dubbed intrinsic Higgs states or quiver invariants. We demonstrate how the refined Higgs index is naturally decomposed to a sum over partitions of the charge. We conjecture, and show in simple cases, that this decomposition expresses the Higgs index as a sum over a set of partition-induced Abelian quivers of the same total charge but generically of smaller rank. Unlike the previous approach inspired by a similar decomposition of the Coulomb index, our formulae compute the quiver invariants directly, and thus offer a self-complete routine for counting BPS states
Non-BPS Dirac-Born-Infeld Solitons
Ioannidou, Theodora; Papadopoulos, George; Sutcliffe, Paul(Department of Mathematical Sciences, Durham University, South Road, Durham, DH1 3LE, U.K.)
1999-01-01
We show that CPn sigma model solitons solve the field equations of a Dirac-Born-Infeld (DBI) action and, furthermore, we prove that the non-BPS soliton/anti-soliton solutions of the sigma model also solve the DBI equations. Using the moduli space approximation we compare the dynamics of the BPS sigma model solitons with that of the associated DBI solitons. We find that for the CP1 case the metric on the moduli space of sigma model solitons is identical to that of the moduli space of DBI solit...
BPS index and 4d N=2 superconformal field theories
Sakai, Kazuhiro
2016-01-01
We study the BPS index for the four-dimensional rank-one N=2 superconformal field theories H_0, H_1, H_2, E_6, E_7, E_8. We consider compactifications of the E-string theory on T^2 in which these theories arise as low energy limits. Using this realization we clarify the general structure of the BPS index. The index is characterized by two exponents and a sequence of invariants. We determine the exponents and the first few invariants.
BPS index and 4d N = 2 superconformal field theories
Sakai, Kazuhiro
2016-07-01
We study the BPS index for the four-dimensional rank-one N = 2 superconformal field theories H 0 , H 1 , H 2 , E 6 , E 7 , E 8. We consider compactifications of the E-string theory on T 2 in which these theories arise as low energy limits. Using this realization we clarify the general structure of the BPS index. The index is characterized by two exponents and a sequence of invariants. We determine the exponents and the first few invariants.
Composite BPS skyrmions from an exact isospin symmetry breaking
Klimas, Pawel
2016-01-01
We study the BPS Skyrme model with potentials breaking the isospin symmetry and analyse how properties of exact solitonic solutions depend on a form of the isospin breaking potential. In the case of the strong symmetry breaking a new topologic structure is observed which enables us to decompose a BPS skyrmion into a lower dimensional defect localised on a brane (kink). We investigate some thermodynamical properties of such solitons as well as the role of the symmetry breaking potential in the resulting mean-field equation of state.
Nakagawa, Nozomi; Hasegawa, Hideyuki; Kanai, Hiroshi
2004-05-01
We have developed the phased tracking method [H. Kanai, M. Sato, Y. Koiwa and N. Chubachi: IEEE Trans. UFFC 43 (1996) 791.] for measuring the minute change in thickness during one heartbeat and the elasticity of the arterial wall with transcutaneous ultrasound. When this method is applied to a plane perpendicular to the axis of the artery (short-axis plane) using a linear-type probe, only an ultrasonic beam which passes through the center of the artery coincides with the direction of the change in thickness. At other beam positions, the wall motion cannot be accurately tracked because the direction of wall expansion slips off the beam. To obtain the cross-sectional image of elasticity in the short-axis plane using transcutaneous ultrasound, in this paper, the directions of ultrasonic beams are designed so that each beam always passes through the center of the artery; thus, they always coincide with the direction of the wall expansion. In basic experiments, the accuracy in elasticity measurement was evaluated using a silicone rubber tube. In in vivo experiments, the minute change in wall thickness was measured along each ultrasonic beam, and the cross-sectional image of elasticity was obtained in the short-axis plane with transcutaneous ultrasound.
Tang, Jiang; Hasegawa, Hideyuki; Kanai, Hiroshi
2005-06-01
For the assessment of the elasticity of the arterial wall, we have developed the phased tracking method [H. Kanai et al.: IEEE Trans. Ultrason. Ferroelectr. Freq. Control 43 (1996) 791] for measuring the minute change in thickness due to heartbeats and the elasticity of the arterial wall with transcutaneous ultrasound. For various reasons, for example, an extremely small deformation of the wall, the minute change in wall thickness during one heartbeat is largely influenced by noise in these cases and the reliability of the elasticity distribution obtained from the maximum change in thickness deteriorates because the maximum value estimation is largely influenced by noise. To obtain a more reliable cross-sectional image of the elasticity of the arterial wall, in this paper, a matching method is proposed to evaluate the waveform of the measured change in wall thickness by comparing the measured waveform with a template waveform. The maximum deformation, which is used in the calculation of elasticity, was determined from the amplitude of the matched model waveform to reduce the influence of noise. The matched model waveform was obtained by minimizing the difference between the measured and template waveforms. Furthermore, a random error, which was obtained from the reproducibility among the heartbeats of the measured waveform, was considered useful for the evaluation of the reliability of the measured waveform.
BPS Degeneracies and Superconformal Index in Diverse Dimensions
Iqbal, Amer
2012-01-01
We present a unifying theme relating BPS partition functions and superconformal indices. In the case with complex SUSY central charges (as in N=2 in d=4 and N=(2,2) in d=2) the known results can be reinterpreted as the statement that the BPS partition functions can be used to compute a specialization of the superconformal indices. We argue that in the case with real central charge in the supersymmetry algebra, as in N=1 in d=5 (or the N=2 in d=3), the BPS degeneracy captures the full superconformal index. Furthermore, we argue that refined topological strings, which captures 5d BPS degeneracies of M-theory on CY 3-folds, can be used to compute 5d supersymmetric index including in the sectors with 3d defects for a large class of 5d superconformal theories. Moreover, we provide evidence that distinct Calabi-Yau singularities which are expected to lead to the same SCFT yield the same index.
AdS/CFT and BPS Strings in Four Dimensions
Alishahiha, M; Alishahiha, Mohsen; Oz, Yaron
1999-01-01
We consider N=2 superconformal theories defined on a 3+1 dimensional hyperplane intersection of two sets of M5 branes. These theories have (tensionless) BPS string solitons. We use a dual supergravity formulation to deduce some of their properties via the AdS/CFT correspondence.
Vortex partition functions, wall crossing and equivariant Gromov-Witten invariants
Bonelli, Giulio; Tanzini, Alessandro; Vasko, Petr
2013-01-01
In this paper we identify the problem of equivariant vortex counting in a (2,2) supersymmetric two dimensional quiver gauged linear sigma model with that of computing the equivariant Gromov-Witten invariants of the GIT quotient target space determined by the quiver. We provide new contour integral formulae for the I and J-functions encoding the equivariant quantum cohomology of the target space. Its chamber structure is shown to be encoded in the analytical properties of the integrand. This is explained both via general arguments and by checking several key cases. We show how several results in equivariant Gromov-Witten theory follow just by deforming the integration contour. In particular we apply our formalism to compute Gromov-Witten invariants of the C^3/Z_n orbifold and of the Uhlembeck (partial) compactification of the moduli space of instantons on C^2. Moreover, we analyse dualities of quantum cohomology rings of holomorphic vector bundles over Grassmannians, which are relevant to BPS Wilson loop algeb...
Non-perturbative effects and wall-crossing from topological strings
Collinucci, Andres; Uranga, Angel M
2009-01-01
We argue that the Gopakumar-Vafa interpretation of the topological string partition function can be used to compute and resum certain non-perturbative brane instanton effects of type II CY compactifications. In particular the topological string A-model encodes the non-perturbative corrections to the hypermultiplet moduli space metric from general D1/D(-1)-brane instantons in 4d N=2 IIB models. By introducing fluxes and/or orientifolds and/or D-branes, we describe the reduction to 4d N=1 models, and describe the computation of non-perturbative superpotential contributions from resummed brane instantons. We argue that the connection between non-perturbative effects and the topological string underlies the continuity and holomorphy of non-perturbative effects across lines of BPS stability. The computation of non-perturbative effects from the topological string requires a 3d circle compactification and T-duality, relating effects from particles and instantons, suggesting a realization of the Kontsevich-Soibelmann...
Trajectory measurements of a wall jet impinging onto a forward facing step entering a cross-flow
This study examines a horizontal wall jet impinging onto a forward facing step in a cross-flow. Planar laser induced fluorescence (PLIF) experiments in a water channel indicate that the wall-jet flow after impinging onto the step, becomes a vertical jet with an elliptical cross section. Experiments indicate that the jet trajectory scales with the perimeter of the elliptical jet issuing vertically into the cross-flow. The trajectory consists of three regions: the near-field region which is well described by a power law with an exponent of 1/2, the mid-field region where the jet is fully bent over which is described by a power law with an exponent of 1/3, and a far-field region where the jet is dominated by the cross-flow. This paper provides a prediction of the plume behaviour based on the geometric and initial conditions of the jet (diameter, step height, distance from jet to step, and velocity ratio) alone. The Briggs entrainment model for a round jet was also used to predict the trajectories of the jet in the cross-flow. It was found that the entrainment coefficients, α and β, for the elliptical jet case had average values of 0.15 and 0.58 respectively.
Ahmed, Malik Nazir
1999-01-01
A Constrained Torsional Analysis of Thin-Walled Variable Cross-Section Multi-Cell Laminated Composite Beams has been undertaken . The existing Isotopic theory has been modified using the effective engineering elastic constants to cater for the Composite structures under torsional loads. The relevant computer programs for the Composite structure analysis have also been developed. The results are discussed in detail for single-cell and multi-cell prismatic/tapered beams for all [0/45/-45/90], l...
Domain Walls Zoo in Supersymmetric QCD
Smilga, A V
1998-01-01
Solving numerically the equations of motion for the effective lagrangian describing supersymmetric QCD with the SU(2) gauge group, we find a menagerie of complex domain wall solutions connecting different chirally asymmetric vacua. Some of these solutions are BPS saturated walls; they exist when the mass of the matter fields does not exceed some critical value m m*, the complex walls disappear altogether and only the walls connecting a chirally asymmetric vacuum with the chirally symmetric one survive.
$Spin(7)$ Compactifications and 1/4-BPS Vacua in Heterotic Supergravity
Angus, Stephen; Svanes, Eirik Eik
2015-01-01
We continue the investigation into non-maximally symmetric compactifications of the heterotic string. In particular, we consider compactifications where the internal space is allowed to depend on two or more external directions. For preservation of supersymmetry, this implies that the internal space must in general be that of a $Spin(7)$ manifold, which leads to a $1/4$-BPS four-dimensional non-supersymmetric perturbative vacuum. We find that these solutions allow for internal geometries previously excluded by the domain-wall-type solutions, and hence the resulting four-dimensional superpotential is more generic. In particular, we find an interesting resemblance to the superpotentials that appear in non-geometric flux compactifications of type II string theory. If the vacua are to be used for phenomenological applications, they must be lifted to a maximally symmetric one by some non-perturbative or higher-order effect.
classically or semi classically as their origin here, but to obtain exact results a rather quantum mechanical treatment is also handled. The order of magnitude of quantum effects derived from uncertainty principle. Through this individual research introduced here, the scattering process of the γ radiation including Thomson scattering in one extreme, together with Compton scattering in other extreme leads to heating plasma media again helps to produce thermonuclear reaction yet. The absorption of the γ radiation by the plasma media included also, Rayleigh and Raman (Stokes) scattering in turn served as another agent to heat the cold plasma. Also in this paper, all the possible cross sections of the above mentioned collisions calculated where as the probability of the impact between incident γ-ray with walls, in magnetic confined devices (including tokamaks) has been taken into account and the diagnostics aspects are also discussed. In the conclusion and remarks the fruitfulness of the method elucidated. The simulation of theory is in development. (author)
One-loop Amplitudes as BPS state sums
Florakis, Ioannis
2013-01-01
We review a novel method for evaluating one-loop BPS-saturated amplitudes in string theory. Contrary to traditional techniques of unfolding the fundamental domain F against the Narain lattice, which are only valid in certain regions of the moduli space and which obscure the T- duality invariance of the result, we will describe how the elliptic genus can be represented as a linear combination of certain absolutely convergent Poincar\\'e series, against which F can be unfolded. The result can be expressed as a sum of one-loop contributions of perturbative BPS-states in a manifestly T-duality invariant fashion, valid at any point of (the perturbative) moduli space. Within this framework, the singularity structure of amplitudes around points of gauge symmetry enhancement becomes crystal clear and a series of applications is given in order to better illustrate the power of this approach.
The M2/M5 BPS Partition Functions from Supergravity
Silva, Pedro J
2009-01-01
In the framework of the AdS/CFT duality, we calculate the supersymmetric partition function of the superconformal field theories living in the world volume of either $N$ $M2$-branes or $N$ $M5$-branes. We used the dual supergravity partition function in a saddle point approximation over supersymmetric Black Holes. Since our BHs are written in asymptotically global $AdS_{d+1}$ co-ordinates, the dual SCFTs are in $R x S^{d}$ for $d=2,5$. The resulting partition function shows phase transitions, constraints on the phase space and allowed us to identify unstable BPS Black hole in the $AdS$ phase. This configurations should corresponds to unstable configurations in the dual theory. We also report an intriguing relation between the most general Witten Index, computed in the above theories, and our BPS partition functions.
We study a class of exact supersymmetric solutions of type IIB Supergravity. They have an SO(4) x SU(2) x U(1) isometry and preserve generically 4 of the 32 supersymmetries of the theory. Asymptotically AdS5 x S5 solutions in this class are dual to 1/8 BPS chiral operators which preserve the same symmetries in the N = 4 SYM theory. They are parametrized by a set of four functions that satisfy certain differential equations. We analyze the solutions to these equations in a large radius asymptotic expansion: they carry charges with respect to two U(1) KK gauge fields and their mass saturates the expected BPS bound
We study a class of exact supersymmetric solutions of type IIB Supergravity. They have an SO(4) x SU(2) x U(1) isometry and preserve generically 4 of the 32 supersymmetries of the theory. Asymptotically AdS5 x S5 solutions in this class are dual to 1/8 BPS chiral operators which preserve the same symmetries in the N = 4 SYM theory. They are parametrized by a set of four functions that satisfy certain differential equations. We analyze the solutions to these equations in a large radius asymptotic expansion: they carry charges with respect to two U(1) KK gauge fields and their mass saturates the expected BPS bound. (author)
Nuclear binding energies from a BPS Skyrme model
Adam, C.; Naya, C.; Sanchez-Guillen, J.(Departamento de Física de Partículas, Universidad de Santiago de Compostela and Instituto Galego de Física de Altas Enerxias (IGFAE), Santiago de Compostela, E-15782, Spain); Wereszczynski, A.
2013-01-01
Recently, within the space of generalized Skyrme models, a BPS submodel was identified which reproduces some bulk properties of nuclear matter already on a classical level and, as such, constitutes a promising field theory candidate for the detailed and reliable description of nuclei and hadrons. Here we extend and further develop these investigations by applying the model to the calculation of nuclear binding energies. Concretely, we calculate these binding energies by including the classica...
Properties of non-BPS SU(3) monopoles
This paper is concerned with magnetic monopole solutions of SU(3) Yang-Mills-Higgs system beyond the Bogomol'nyi-Prasad-Sommerfield limit. The different SU(2) embeddings, which correspond to the fundamental monopoles, as well the embedding along composite root are studied. The interaction of two different fundamental monopoles is considered. Dissolution of a single fundamental non-BPS SU(3) monopole in the limit of the minimal symmetry breaking is analyzed. (author)
BPS monopole in the space of boundary conditions
The space of all possible boundary conditions that respect the self-adjointness of the Hamiltonian operator is known to be given by the group manifold U(2) in one-dimensional quantum mechanics. In this paper we study non-Abelian Berry’s connections in the space of boundary conditions in a simple quantum mechanical system. We consider a system for a free spinless particle on a circle with two point-like interactions described by the U(2) × U(2) family of boundary conditions. We show that, for a certain SU(2) ⊂ U(2) × U(2) subfamily of boundary conditions, all the energy levels become doubly-degenerate thanks to the so-called higher-derivative supersymmetry, and the non-Abelian Berry’s connection in the ground-state sector is given by the Bogomolny–Prasad–Sommerfield (BPS) monopole of SU(2) Yang–Mills–Higgs theory. We also show that, in the ground-state sector of this quantum mechanical model, the matrix elements of the position operator give the adjoint Higgs field that satisfies the BPS equation. It is also discussed that Berry’s connections in the excited-state sectors are given by non-BPS ’t Hooft–Polyakov monopoles. (paper)
Some exact BPS solutions for exotic vortices and monopoles
Ramadhan, Handhika S.
2016-07-01
We present several analytical solutions of BPS vortices and monopoles in the generalized Abelian Maxwell-Higgs and Yang-Mills-Higgs theories, respectively. These models have recently been extensively studied and several exact solutions have already been obtained in [1,2]. In each theory, the dynamics is controlled by the additional two positive scalar-field-dependent functions, f (| ϕ |) and w (| ϕ |). For the case of vortices, we work in the ordinary symmetry-breaking Higgs potential, while for the case of monopoles we have the ordinary condition of the Prasad-Sommerfield limit. Our results generalize the exact solutions found previously. We also present solutions for BPS vortices with higher winding number. These solutions suffer from the condition that w (| ϕ |) has negative value at some finite range of r, but we argue that since it satisfies the weaker positive-value conditions then the corresponding energy density is still positive-definite and, thus, they are acceptable BPS solutions.
Diet and its role in interstitial cystitis/bladder pain syndrome (IC/BPS) and comorbid conditions.
Friedlander, Justin I; Shorter, Barbara; Moldwin, Robert M
2012-06-01
What's known on the subject? and What does the study add? Nearly 90% of patients with interstitial cystitis/bladder pain syndrome (IC/BPS) report sensitivities to a wide variety of dietary comestibles. Current questionnaire-based literature suggests that citrus fruits, tomatoes, vitamin C, artificial sweeteners, coffee, tea, carbonated and alcoholic beverages, and spicy foods tend to exacerbate symptoms, while calcium glycerophosphate and sodium bicarbonate tend to improve symptoms. At present we recommend employing a controlled method to determine dietary sensitivities, such as an elimination diet, in order to identify sensitivities while at the same time maintain optimal nutritional intake. We review current literature with regard to diet's effect upon IC/BPS and common comorbidities (irritable bowel syndrome, fibromyalgia, chronic fatigue syndrome, neuropathic pain, vulvodynia, and headache) with a focus upon questionnaire-based investigations. We discuss the pathologic mechanisms that may link diet and IC/BPS related-pain, concentrating upon specific comestibles such as acidic foods, foods high in potassium, caffeine, and alcohol. Up to 90% of patients with interstitial cystitis/bladder pain syndrome (IC/BPS) report sensitivities to a wide variety of comestibles. Pathological mechanisms suggested to be responsible for the relationship between dietary intake and symptom exacerbation include peripheral and/or central neural upregulation, bladder epithelial dysfunction, and organ 'cross-talk', amongst others. Current questionnaire-based data suggests that citrus fruits, tomatoes, vitamin C, artificial sweeteners, coffee, tea, carbonated and alcoholic beverages, and spicy foods tend to exacerbate symptoms, while calcium glycerophosphate and sodium bicarbonate tend to improve symptoms. Specific comestible sensitivities varied between patients and may have been influenced by comorbid conditions. This suggests that a controlled method to determine dietary
Domain Wall Equations, Hessian of Superpotential, and Bogomol'nyi Bounds
Chen, Shouxin
2015-01-01
An important question concerning the classical solutions of the equations of motion arising in quantum field theories at the BPS critical coupling is whether all finite-energy solutions are necessarily BPS. In this paper we present a study of this basic question in the context of the domain wall equations whose potential is induced from a superpotential so that the ground states are the critical points of the superpotential. We prove that the definiteness of the Hessian of the superpotential suffices to ensure that all finite-energy domain-wall solutions are BPS. We give several examples to show that such a BPS property may fail such that non-BPS solutions exist when the Hessian of the superpotential is indefinite.
Leontarakis, Konstantinos; Apostolopoulos, George V.
2013-06-01
A cross-hole Electrical Resistivity Tomography (ERT) study was undertaken near the center of Thessaloniki in order to detect the depth of the existing city walls in the planned route of the new city underground train. This cross-hole setup was used for a study of measurements with various electrode arrays in real urban field conditions to evaluate the resolution of the models which is produced by each array and the reliability of the models which is produced by the newly published "MOST" technique. The pole-tripole array (C2-C1P1P2) produces high resolution models, even when only borehole electrodes are used. The bipole-bipole C1C2-P1P2 array, when used for cross-hole measurements only, produces higher resolution models compared to the C1P1-C2P2 array, even with a lower signal-to-noise ratio, which can result in extremely high RMS error, when noise, systematic or not, must be faced. The models of both arrays are greatly improved by the use of surface electrodes. The pole-bipole array (C1-P1P2) is proved to be less accurate in imaging and quite unstable to the noisy urban environment and to systematic errors. Furthermore, the Model Stacking (MOST) interpretation technique leads to better results with models of greater resolution and fewer artifacts compared even with the combined data inversion. Finally, the ERT cross-hole analysis has been reliable in detecting the city walls.
Domain Walls, Black Holes and Supersymmetric Quantum Mechanics.; TOPICAL
Supersymmetric solutions, such as BPS domain walls or black holes, in four- and five-dimensional supergravity theories with eight supercharges can be described by effective quantum mechanics with a potential term. We show how properties of the latter theory can help us to learn about the physics of supersymmetric vacua and BPS solutions in these supergravity theories. The general approach is illustrated in a number of specific examples where scalar fields of matter multiplets take values in symmetric coset spaces
Yu Jingang; Huang Dushu; Huang Kelong; Hong Yong
2011-01-01
A method of cross-linking multi-walled carbon nanotubes by a nucleophilic substitution of brominated multi-walled carbon nanotubes using hydroxypropyl-β-cyclodextrin anions was studied. The modified multi-walled carbon nanotube samples were characterized using thermogravimetric analysis, energy-dispersive X-ray spectros-copy, transmission electron microscopy, scanning electron microscopy, Raman spectroscopy and Fourier transform infrared spectroscopy. The hydroxypropyi-β-cyclodextrin modified multi-walled carbon nanotubes were used as a chiral stationary phase additive for thin-layer chromatography to separate clenbuterol enantiomers, and the chiral separation factor was increased.
On the Moduli Space of non-BPS Attractors for N=2 Symmetric Manifolds
Ferrara, Sergio
2007-01-01
We study the ``flat'' directions of non-BPS extremal black hole attractors for N=2, d=4 supergravities whose vector multiplets' scalar manifold is endowed with homogeneous symmetric special Kahler geometry. The non-BPS attractors with non-vanishing central charge have a moduli space described by real special geometry (and thus related to the d=5 parent theory), whereas the moduli spaces of non-BPS attractors with vanishing central charge are certain Kahler homogeneous symmetric manifolds. The moduli spaces of the non-BPS attractors of the corresponding N=2, d=5 theories are also indicated, and shown to be rank-1 homogeneous symmetric manifolds.
BPS Limit of Multi- D- and DF-strings in Boundary String Field Theory
Go, Gyungchoon; Ishida, Akira; Kim, Yoonbai
2007-01-01
A BPS limit is systematically derived for straight multi- D- and DF-strings from the D3D3bar system in the context of boundary superstring field theory. The BPS limit is obtained in the limit of thin D(F)-strings, where the Bogomolnyi equation supports singular static multi-D(F)-string solutions. For the BPS multi-string configurations with arbitrary separations, BPS sum rule is fulfilled under a Gaussian type tachyon potential and reproduces exactly the descent relation. For the DF-strings (...
Adam, C.; Sanchez-Guillen, J.; Wereszczynski, A.; Zakrzewski, W. J.
2013-01-01
The Bogomol’nyi-Prasad-Sommerfield (BPS) baby Skyrme models are submodels of baby Skyrme models, where the nonlinear sigma model term is suppressed. They have Skyrmion solutions saturating a BPS bound, and the corresponding static energy functional is invariant under area-preserving diffeomorphisms (APDs). Here we show that the solitons in the BPS baby Skyrme model, which carry a nontrivial topological charge Qb∈π2(S2) (a winding number), are dual to vortices in a BPS vortex model with a topological charge Qv∈π1(S1) (a vortex number), in the sense that there is a map between the BPS solutions of the two models. The corresponding energy densities of the BPS solutions of the two models are identical. A further consequence of the duality is that the dual BPS vortex models inherit the BPS property and the infinitely many symmetries (APDs) of the BPS baby Skyrme models. Finally, we demonstrate that the same topological duality continues to hold for the U(1) gauged versions of the models.
Topological duality between vortices and planar skyrmions in BPS theories with APD symmetries
Adam, C; Wereszczynski, A; Zakrzewski, W J
2012-01-01
The BPS baby Skyrme models are submodels of baby Skyrme models, where the nonlinear sigma model term is suppressed. They have skyrmion solutions saturating a BPS bound, and the corresponding static energy functional is invariant under area-preserving diffeomorphisms (APDs). Here we show that the solitons in the BPS baby Skyrme model, which carry a nontrivial topological charge $Q_{b} \\in \\pi_2(S^2)$ (a winding number), are dual to vortices in a BPS vortex model with a topological charge $Q_{v}\\in \\pi_1(S^1)$ (a vortex number), in the sense that there is a map between the BPS solutions of the two models. The corresponding energy densities of the BPS solutions of the two models are identical. A further consequence of the duality is that the dual BPS vortex models inherit the BPS property and the infinitely many symmetries (APDs) of the BPS baby Skyrme models. Finally, we demonstrate that the same topological duality continues to hold for the U(1) gauged versions of the models.
Topological duality between vortices and planar skyrmions in BPS theories with APD symmetries
Adam, C.; Sanchez-Guillen, J.; Wereszczynski, A.; Zakrzewski, W. J.
2012-01-01
The BPS baby Skyrme models are submodels of baby Skyrme models, where the nonlinear sigma model term is suppressed. They have skyrmion solutions saturating a BPS bound, and the corresponding static energy functional is invariant under area-preserving diffeomorphisms (APDs). Here we show that the solitons in the BPS baby Skyrme model, which carry a nontrivial topological charge $Q_{b} \\in \\pi_2(S^2)$ (a winding number), are dual to vortices in a BPS vortex model with a topological charge $Q_{v...
Twistor Parametrization of Locally BPS Super-Wilson Loops
C. Vergu
2016-01-01
We consider the kinematics of the locally BPS super-Wilson loop in $\\mathcal{N}=4$ super-Yang-Mills with scalar coupling from a twistorial point of view. We find that the kinematics can be described either as supersymmetrized pure spinors or as a point in $G_{2\\vert 2}(4\\vert 4) \\times G_{2\\vert 2}(4\\vert 4)$. In this description of the kinematics the scalar--scalar correlation function appearing in the one-loop evaluation of the super-Wilson loop can be neatly written as a sum of four super-...
Twistor Parametrization of Locally BPS Super-Wilson Loops
Vergu, C
2016-01-01
We consider the kinematics of the locally BPS super-Wilson loop in $\\mathcal{N}=4$ super-Yang-Mills with scalar coupling from a twistorial point of view. We find that the kinematics can be described either as supersymmetrized pure spinors or as a point in $G_{2\\vert 2}(4\\vert 4) \\times G_{2\\vert 2}(4\\vert 4)$. In this description of the kinematics the scalar--scalar correlation function appearing in the one-loop evaluation of the super-Wilson loop can be neatly written as a sum of four super-determinants.
Design of BPS digital frontend for software defined radio receiver
王洪梅; KIM Jae-hyung; 王法广; LEE Sang-hyuk; 王雪松
2015-01-01
In radio receivers, complete implementation of the software defined radio (SDR) concept is mainly limited by frontend. Based on bandpass sampling (BPS) theory, a flexible digital frontend (DFE) platform for SDR receiver is designed. In order to increase the processing speed, Gigabit Ethernet was applied in the platform at speed of 5×108 bit/s. By appropriate design of interpolant according to the position of input RF signals, multi-band receiving can be realized in the platform with suppression more than 35 dB without changing hardware.
Improved concept models for straight thin-walled columns with box cross section
Yu-cheng LIU
2008-01-01
This paper focuses on developing improved concept models for straight thin-walled box sectional columns which can better predict the peak crushing force that occurs during crashworthiness analyses.We develop a nonlinear translational spring based on previous research and apply such a spring element to build the enhanced concept models.The work presented in this article is developed on the basis of the publication of the author(Liu and Day,2006b)and has been applied in a crashworthiness design issue,which is presented by the author in another paper(Liu,2008).
Marginal Stability and the Metamorphosis of BPS States
Ritz, A; Vainshtein, A I; Voloshin, M B; Ritz, Adam; Shifman, Mikhail; Vainshtein, Arkady; Voloshin, Mikhail
2001-01-01
We discuss the restructuring of the BPS spectrum which occurs on certain submanifolds of the moduli/parameter space -- the curves of the marginal stability (CMS) -- using quasiclassical methods. We argue that in general a `composite' BPS soliton swells in coordinate space as one approaches the CMS and that, as a bound state of two `primary' solitons, its dynamics in this region is determined by supersymmetric quantum mechanics with a short range potential. Near the CMS the bound state resembles a deuteron with a wave function which is highly spread out. Precisely on the CMS the bound state level reaches the continuum, the composite state delocalizes in coordinate space, and restructuring of the spectrum can occur. We present a detailed analysis of this behavior in a two-dimensional N=2 Wess-Zumino model with two chiral fields, and then discuss how it arises in the context of `composite' dyons near weak coupling CMS curves in N=2 supersymmetric gauge theories. We also consider exceptional cases where some stat...
BPS states in the duality web of the Omega deformation
Hellerman, Simeon; Orlando, Domenico; Reffert, Susanne
2013-06-01
In this note, we study different limits of an Ω-deformed (2, 0) six-dimensional gauge theory realized in an M-theory fluxtrap background. Via a chain of dualities, we connect the Ω-deformed sym to a new four-dimensional gauge theory which we refer to as the reciprocal gauge theory. This theory has several properties in common with Liouville field theory, such as its gauge coupling b 2 = ɛ 2/ ɛ 1, and its behavior under S-duality. Finally, we realize the bps states on the sym side of the agt correspondence and follow them along the chain of dualities. In the fluxtrap frame, we are dealing with two distinct types of states localized in different radial positions, while in the reciprocal frame, we find single states carrying both charges localized in one place which appear to be perturbatively stable. Our microscopic picture of the small- b limit exhibits semiclassically bps bound states, which are not visible at the level of the partition function.
BPS States in the Duality Web of the Omega deformation
Hellerman, Simeon; Reffert, Susanne
2013-01-01
In this note, we study different limits of an Omega-deformed (2,0) six-dimensional gauge theory realized in a M-theory fluxtrap background. Via a chain of dualities, we connect the Omega-deformed SYM to a new four-dimensional gauge theory which we refer to as the reciprocal gauge theory. This theory has several properties in common with Liouville field theory, such as its gauge coupling b^2 =\\epsilon_2 / \\epsilon_1, and its behavior under S-duality. Finally, we realize the BPS states on the SYM side of the AGT correspondence and follow them along the chain of dualities. In the fluxtrap frame, we are dealing with two distinct types of states localized in different radial positions, while in the reciprocal frame, we find single states carrying both charges localized in one place which appear to be perturbatively stable. Our microscopic picture of the small-b limit exhibits semiclassically BPS bound states, which are not visible at the level of the partition function.
BPS black hole horizons in N=2 gauged supergravity
We study static BPS black hole horizons in four dimensional N=2 gauged supergravity coupled to nv-vector multiplets and with an arbitrary cubic prepotential. We work in a symplectically covariant formalism which allows for both electric and magnetic gauging parameters as well as dyonic background charges and obtain the general solution to the BPS equations for horizons of the form AdS2×Σg. In particular this means we solve for the scalar fields as well as the metric of these black holes as a function of the gauging parameters and background charges. When the special Kähler manifold is a symmetric space, our solution is completely explicit and the entropy is related to the familiar quartic invariant. For more general models our solution is implicit up to a set of holomorphic quadratic equations. For particular models which have known embeddings in M-theory, we derive new horizon geometries with dyonic charges and numerically construct black hole solutions. These correspond to M2-branes wrapped on a Riemann surface in a local Calabi-Yau five-fold with internal spin
Scaling BPS Solutions and pure-Higgs States
Bena, Iosif; de Boer, Jan; El-Showk, Sheer; Bleeken, Dieter Van den
2012-01-01
Depending on the value of the coupling, BPS states of type II string theory compactified on a Calabi-Yau manifold can be described as multicenter supergravity solutions or as states on the Coulomb or the Higgs branch of a quiver gauge theory. While the Coulomb-branch states can be mapped one-to-one to supergravity states, this is not automatically so for Higgs-branch states. In this paper we explicitly compute the BPS spectrum of the Higgs branch of a three-center quiver with a closed loop, and identify the subset of states that are in one-to-one correspondence with Coulomb/supergravity multicenter states. We also show that there exist additional "pure-Higgs" states, that exist if and only if the charges of the centers can form a scaling solution. Using generating function techniques we compute the large charge degeneracy of the "pure-Higgs" sector and show that it is always exponential. We also construct the map between Higgs- and Coulomb-branch states, discuss its relation to the Higgs-Coulomb map of one of...
Melcher, G P; Reed, K D; Rinaldi, M. G.; Lee, J. W.; Pizzo, P A; Walsh, T. J.
1991-01-01
Patients with disseminated infections caused by Trichosporon beigelii have a circulating antigen that cross-reacts with the polysaccharide capsule of Cryptococcus neoformans. We studied the localization of this antigen by immunoelectron microscopy in a rabbit model of experimental disseminated trichosporonosis. Deparaffinized lung sections were examined by using a murine monoclonal anti-cryptococcal polysaccharide antibody and colloidal gold particles coated with goat antibody to murine immun...
Wang, Guangjun; Yu, Ermeng; Li, Zhifei; Yu, Deguang; Wang, Haiying; Gong, Wangbao
2016-06-01
The present study was conducted to evaluate the feasibility of replacing fish meal (FM) with bioactive peptides (BPs) in diet of white shrimp ( Litopenaeus vannamei). The changes in growth performance, body composition, non-specific immunity, and water quality were examined after the shrimp were fed four diets, in which 0% (control), 33.3%, 66.7% and 100% of FM was replaced by BPs, respectively. The groups were designated as Con, 1/3BPs, 2/3BPs, and 3/3BPs. A total of 720 shrimp with an initial body weight of 1.46 ± 0.78 g were fed the experimental diets for 56 days. The results revealed that: 1) the weight gain rate (WGR) in 1/3BPs, 2/3BPs, and 3/3BPs was significantly higher than that in Con ( P levels of acid phosphatase (ACP), lysozyme (LZM), superoxide dismutase (SOD), phenol oxidase (PO) and bactericidal activity increased significantly with the inclusion of BPs; 4) in terms of water quality, no significant difference was found in pH and dissolved oxygen among diets during the whole experimental period. Moreover, even though nitrite and ammonium levels tended to increase with time, there was no significant difference among groups. The results indicated that BPs is an applicable alternative of protein source, which can substitute FM in the diets of L. vannamei; it is able to effectively promote growth performance and improve immunity. Moreover, BPs in the diets had no negative impact on water quality.
A Monte Carlo procedure has been applied in this work in order to address the impact of activation cross-sections (XS) uncertainties on contact dose rate and decay heat calculations for the outboard first wall (FW) of a magnetic fusion energy (MFE) demonstration (DEMO) reactor. The XSs inducing the major uncertainty in the prediction of activation related quantities have been identified. Results have shown that for times corresponding to maintenance activities the uncertainties effect is insignificant since the dominant XSs involved in these calculations are based on accurate experimental data evaluations. However, for times corresponding to waste management/recycling activities, the errors induced by the XSs uncertainties, which in this case are evaluated using systematic models, must be considered. It has been found that two particular isotopes, 6Co and 94Nb, are key contributors to the global DEMO FW activation uncertainty results. In these cases, the benefit from further improvements in the accuracy of the critical reaction XSs is discussed
A Monte Carlo procedure has been applied in this work in order to address the impact of activation cross sections (XS) uncertainties on contact dose rate and decay heat calculations for the outboard first wall (FW) of a magnetic fusion energy (MFE) demonstration (DEMO) reactor. The XSs inducing the major uncertainty in the prediction of activation related quantities have been identified. Results have shown that for times corresponding to maintenance activities the uncertainties effect is insignificant since the dominant XSs involved in these calculations are based on accurate experimental data evaluations. However, for times corresponding to waste management/recycling activities, the errors induced by the XSs uncertainties, which in this case are evaluated using systematic models, must be considered. It has been found that two particular isotopes, 60Co and 94Nb, are key contributors to the global DEMO FW activation uncertainty results. In these cases, the benefit from further improvements in the accuracy of the critical reaction XSs is discussed
Seffer, J.-F.; Detriche, S.; Nagy, J. B.; Delhalle, J.; Mekhalif, Z.
2014-06-01
Surface modification of oxidized carbon nanotubes (O-CNTs) with silicon based anchoring groups (R-SiR3) is a relatively uncommon approach of the CNTs functionalization. Hydrosilane derivatives constitute an attractive subclass of compounds for silanization reactions on the CNTs surface. In this work, we report on the ZnCl2 catalytically controlled reaction (hydrosilane dehydrogenative cross-coupling, DHCC) of fluorinated hydrosilane probes with the carboxylic functions present on the surface of oxidized multi-wall carbon nanotubes. Carbon nanotubes functionalized with essentially alcohol groups are also used to compare the selectivity of zinc chloride toward carboxylic groups. To assess the efficiency of functionalization, X-ray Photoelectron Spectroscopy is used to determine the qualitative and quantitative composition of the different samples. Solubility tests on the oxidized and silanized MWNTs are also carried out in the framework of the Hansen Solubility Parameters (HSP) theory to apprehend at another scale the effect of DHCC.
System design and development of a low data rate voice (1200 bps) rate converter
Hauser, J. P.
1992-09-01
This report presents both a high level and a detailed design for a low data rate voice Rate Converter (RC). On the transmit side, converter reduces 2400 bps voice generated by an Advanced Narrowband Digital Voice Terminal (ANDVT) to a 1200 bps bit stream. On the receive Bide it converts the 1200 bps bit stream back to a 2400 bps stream in ANDVT format. Rate reduction is accomplished with little degradation to the inherent voice quality of the ANDVT. This primary focus is upon the real-time software design which is implemented using VxWorks, a real-time, multi-tasking operating system and development environment. The high level design defines four tasks, each having its own execution thread and its own pipe to facilitate inter-task communication. The Supervisor Task performs initialization and managers input of commands and data to the RC. The Compressor Task reduces a 2400 bps bit stream to 1200 bps while the Decompressor Task converts from 1200 bps back to 2400 bps. The Output Task manages the output of data from the RC. Latter sections of this report describe the software in detail.
Periodic inspection of steam generator tubing is an important consideration in the efficient operation of a power generating facility. Since the operating life of these generators is finite, failures will occur. Due to the chemistry of the environment, thermal cycling, and other factors, flaws may develop that can cause rapid deterioration of the tubing while the overall performance of the unit may appear normal. In earlier presentation, the authors presented an ultrasonic bore-side array transducer which can be used with a conventional flaw detector instrument for the location of circumferential crack type defects on the outside tube surface. since that time, much additional experience has been gained on the performance of these probes. Probe performance has been characterized using fatigue crack samples and these results are reviewed. Probes have also been developed having 16 elements for use in larger diameter (25 mm) tubes. The bore-side array concept has been expanded to normal incidence tube well inspection allowing simultaneous wall thickness and eccentricity measurement which is very useful in the assessment of tube wastage and deformation. Preliminary data obtained in this area is presented
BPS String Webs in the 6-dim (2,0) Theories
Lee, K M; Lee, Ki-Myeong; Yee, Ho-Ung
2007-01-01
In the Coulomb phase of the 6-dim (2,0) superconformal theories, the 1/4, 1/8, 1/16 BPS selfdual string webs are argued to exist such that the spatial SO(5) and internal SO(5) rotations are correlated. The basic constituents are 1/2 BPS strings and 1/4 BPS string junctions. One support comes from the existence of the similar BPS dyonic monostring webs in 5-dim maximally supersymmetric gauge theories. Another comes from the study of the supersymmetry of the intersecting M2 brane stripes terminating on M5 branes. We also discuss the related BPS webs in little string theories and other theories.
Michael Schnoor
2015-01-01
Full Text Available Leukocyte extravasation is one of the essential and first steps during the initiation of inflammation. Therefore, a better understanding of the key molecules that regulate this process may help to develop novel therapeutics for treatment of inflammation-based diseases such as atherosclerosis or rheumatoid arthritis. The endothelial adhesion molecules ICAM-1 and VCAM-1 are known as the central mediators of leukocyte adhesion to and transmigration across the endothelium. Engagement of these molecules by their leukocyte integrin receptors initiates the activation of several signaling pathways within both leukocytes and endothelium. Several of such events have been described to occur during transendothelial migration of all leukocyte subsets, whereas other mechanisms are known only for a single leukocyte subset. Here, we summarize current knowledge on regulatory mechanisms of leukocyte extravasation from a leukocyte and endothelial point of view, respectively. Specifically, we will focus on highlighting common and unique mechanisms that specific leukocyte subsets exploit to succeed in crossing endothelial monolayers.
In this study, we fabricated optically transparent and electrically conductive multi-walled carbon nanotube (MWCNT) thin films using a spray-coating technique. The transparency and the electrical resistance of thin film are dependent on the nanotube content deposited on the polyethylene terephthalate (PET) substrate. Poly(acrylic acid) (PAA) and poly(N-vinyl pyrrolidone) (PVP) were used as adhesion promoters to improve MWCNT coating more significantly. The cross-linked polymer resulted in a superior bond between the MWCNTs and the substrates. The surface electrical resistance was significantly lower than the original sheet after nitric acid (HNO3) treatment because of the removed surfactant and the increased interconnecting networks of MWCNT bundles, thus improving the electrical and optical properties of the films. Stronger interaction between the MWCNTs and the substrates resulted in lower decomposition of the polymer chain and less amounts of MWCNTs separated into the HNO3 solution. The lower sheet electrical resistance of PVP/PAA-g-MWCNT conductive films on the PET substrate was because of a more complete conductive path with the cross-linked polymer than that without. Such an improved sheet of electrical resistance varied from 8.83 x 104 Ω/□ to 2.65 x 103 Ω/□ with 5.0 wt.% PVP/PAA-g-MWCNT sprayed on the PET after acid treatment.
Huang, Yuan-Li; Tien, Hsi-Wen [Department of Chemical Engineering, National Tsing-Hua University, Hsin-Chu 30043, Taiwan (China); Ma, Chen-Chi M., E-mail: ccma@che.nthu.edu.tw [Department of Chemical Engineering, National Tsing-Hua University, Hsin-Chu 30043, Taiwan (China); Teng, Chih-Chun [Department of Chemical Engineering, National Tsing-Hua University, Hsin-Chu 30043, Taiwan (China); Yu, Yi-Hsiuan [Department of Chemical Engineering, National Tsing-Hua University, Hsin-Chu 30043, Taiwan (China); Chemical Systems Research Division, Chung Shan Institute of Science and Technology, Tao Yuan 32546, Taiwan (China); Yang, Shin-Yi [Department of Chemical Engineering, National Tsing-Hua University, Hsin-Chu 30043, Taiwan (China); Wei, Ming-Hsiung [Chemical Systems Research Division, Chung Shan Institute of Science and Technology, Tao Yuan 32546, Taiwan (China); Wu, Sheng-Yen [Department of Chemical Engineering, National Tsing-Hua University, Hsin-Chu 30043, Taiwan (China)
2011-10-15
In this study, we fabricated optically transparent and electrically conductive multi-walled carbon nanotube (MWCNT) thin films using a spray-coating technique. The transparency and the electrical resistance of thin film are dependent on the nanotube content deposited on the polyethylene terephthalate (PET) substrate. Poly(acrylic acid) (PAA) and poly(N-vinyl pyrrolidone) (PVP) were used as adhesion promoters to improve MWCNT coating more significantly. The cross-linked polymer resulted in a superior bond between the MWCNTs and the substrates. The surface electrical resistance was significantly lower than the original sheet after nitric acid (HNO{sub 3}) treatment because of the removed surfactant and the increased interconnecting networks of MWCNT bundles, thus improving the electrical and optical properties of the films. Stronger interaction between the MWCNTs and the substrates resulted in lower decomposition of the polymer chain and less amounts of MWCNTs separated into the HNO{sub 3} solution. The lower sheet electrical resistance of PVP/PAA-g-MWCNT conductive films on the PET substrate was because of a more complete conductive path with the cross-linked polymer than that without. Such an improved sheet of electrical resistance varied from 8.83 x 10{sup 4} {Omega}/{open_square} to 2.65 x 10{sup 3} {Omega}/{open_square} with 5.0 wt.% PVP/PAA-g-MWCNT sprayed on the PET after acid treatment.
Sethi, P.; Murapaka, C.; Lim, G. J.; Lew, W. S., E-mail: wensiang@ntu.edu.sg [School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371 (Singapore)
2015-11-09
Hall cross structures in magnetic nanowires are commonly used for electrical detection of magnetization reversal in which a domain wall (DW) is conventionally nucleated by a local Oersted field. In this letter, we demonstrate DW nucleation in Co/Ni perpendicular magnetic anisotropy nanowire at the magnetic Hall cross junction. The DWs are nucleated by applying an in-plane pulsed current through the nanowire without the need of a local Oersted field. The change in Hall resistance, detected using anomalous Hall effect, is governed by the magnetic volume switched at the Hall junction, which can be tuned by varying the magnitude of the applied current density and pulse width. The nucleated DWs are driven simultaneously under the spin transfer torque effect when the applied current density is above a threshold. The possibility of multiple DW generation and variation in magnetic volume switched makes nucleation process stochastic in nature. The in-plane current induced stochastic nature of DW generation may find applications in random number generation.
Liouville Equation in 1/8 BPS Geometries
Mitsuka, Yoshihiro
2008-01-01
We investigate the 1/8 BPS geometries with SU(2) x U(1) x SO(4) x R symmetry in IIB supergravity which were classified by Gava et al, (hep-th/0611065). It is desirable to have a complete set of differential equations imposed on the controlling functions such that they are not only necessary but also sufficient to produce supergravity solutions with those symmetries. We work on this issue and find a new differential equation for the controlling functions. For a special case, we exhaust all the remaining constraints and show that they reduce to one Liouville equation. The solutions of this equation produce geometries which are locally equivalent to the near horizon geometries of intersecting D3-branes.
Non-BPS multi-bubble microstate geometries
Bena, Iosif; Katmadas, Stefanos; Turton, David
2015-01-01
We construct the first smooth horizonless supergravity solutions that have two topologically-nontrivial three-cycles supported by flux, and that have the same mass and charges as a non-extremal D1-D5-P black hole. Our configurations are solutions to six-dimensional ungauged supergravity coupled to a tensor multiplet, and uplift to solutions of Type IIB supergravity. The solutions represent multi-center generalizations of the non-BPS solutions of Jejjala, Madden, Ross, and Titchener, which have over-rotating angular momenta. By adding an additional Gibbons-Hawking center, we succeed in lowering one of the two angular momenta below the cosmic censorship bound, and bringing the other very close to this bound. Our results demonstrate that it is possible to construct multi-center horizonless solutions corresponding to non-extremal black holes, and offer the prospect of ultimately establishing that finite-temperature black holes have nontrivial structure at the horizon.
Non-BPS multi-bubble microstate geometries
Bena, Iosif; Bossard, Guillaume; Katmadas, Stefanos; Turton, David
2016-02-01
We construct the first smooth horizonless supergravity solutions that have two topologically-nontrivial three-cycles supported by flux, and that have the same mass and charges as a non-extremal D1-D5-P black hole. Our configurations are solutions to six-dimensional ungauged supergravity coupled to a tensor multiplet, and uplift to solutions of Type IIB supergravity. The solutions represent multi-center generalizations of the non-BPS solutions of Jejjala, Madden, Ross, and Titchener, which have over-rotating angular momenta. By adding an additional Gibbons-Hawking center, we succeed in lowering one of the two angular momenta below the cosmic censorship bound, and bringing the other very close to this bound. Our results demonstrate that it is possible to construct multi-center horizonless solutions corresponding to non-extremal black holes, and offer the prospect of ultimately establishing that finite-temperature black holes have nontrivial structure at the horizon.
Quantum Holonomies from Spectral Networks and Framed BPS States
Gabella, Maxime
2016-08-01
We propose a method for determining the spins of BPS states supported on line defects in 4d {{N}=2} theories of class S. Via the 2d-4d correspondence, this translates to the construction of quantum holonomies on a punctured Riemann surface {{C}} . Our approach combines the technology of spectral networks, which decomposes flat {GL(K,{C})} -connections on {{C}} in terms of flat abelian connections on a K-fold cover of {{C}} , and the skein algebra in the 3-manifold {{C} × [0,1]} , which expresses the representation theory of the quantum group U q (gl K ). With any path on {{C}} , the quantum holonomy associates a positive Laurent polynomial in the quantized Fock-Goncharov coordinates of higher Teichmüller space. This confirms various positivity conjectures in physics and mathematics.
Do all BPS black hole microstates carry zero angular momentum?
Chowdhury, Abhishek; Garavuso, Richard S.; Mondal, Swapnamay; Sen, Ashoke
2016-04-01
From the analysis of the near horizon geometry and supersymmetry algebra it has been argued that all the microstates of single centered BPS black holes with four unbroken supersymmetries carry zero angular momentum in the region of the moduli space where the black hole description is valid. A stronger form of the conjecture would be that the result holds for any sufficiently generic point in the moduli space. In this paper we set out to test this conjecture for a class of black hole microstates in type II string theory on T 6, represented by four stacks of D-branes wrapped on various cycles of T 6. For this system the above conjecture translates to the statement that the moduli space of classical vacua must be a collection of points. Explicit analysis of systems carrying a low number of D-branes supports this conjecture.
Quantum lift of non-BPS flat directions
Bellucci, S. [INFN - Laboratori Nazionali di Frascati, Via Enrico Fermi 4000044 Frascati (Italy)], E-mail: bellucci@lnf.infn.it; Ferrara, S. [INFN - Laboratori Nazionali di Frascati, Via Enrico Fermi 4000044 Frascati (Italy); Physics Department, Theory Unit, CERN, CH 1211, Geneva 23 (Switzerland); Miller Institute for Basic Research in Science, University of California, Berkeley, CA 94720 (United States)], E-mail: sergio.ferrara@cern.ch; Marrani, A. [INFN - Laboratori Nazionali di Frascati, Via Enrico Fermi 4000044 Frascati (Italy); Stanford Institute for Theoretical Physics, Stanford University, Stanford, CA 94305-4060 (United States)], E-mail: marrani@lnf.infn.it; Shcherbakov, A. [INFN - Laboratori Nazionali di Frascati, Via Enrico Fermi 4000044 Frascati (Italy); Museo Storico della Fisica e Centro Studi e Ricerche ' Enrico Fermi' Via Panisperna 89A, 00184 Roma (Italy)], E-mail: ashcherb@lnf.infn.it
2009-02-09
We study N=2, d=4 attractor equations for the quantum corrected two-moduli prepotential F=st{sup 2}+i{lambda}, with {lambda} real, which is the only correction which preserves the axion shift symmetry and modifies the geometry. In the classical case the black hole effective potential is known to have a flat direction. We found that in the presence of D0-D6 branes the black hole potential exhibits a flat direction in the quantum case as well. It corresponds to non-BPS Z{ne}0 solutions to the attractor equations. Unlike the classical case, the solutions acquire non-zero values of the axion field. For the cases of D0-D4 and D2-D6 branes the classical flat direction reduces to separate critical points which turn out to have a vanishing axion field.
Quantum Holonomies from Spectral Networks and Framed BPS States
Gabella, Maxime
2016-01-01
We propose a method for determining the spins of BPS states supported on line defects in 4d $\\mathcal{N}=2$ theories of class S. Via the 2d-4d correspondence, this translates to the construction of quantum holonomies on a punctured Riemann surface $\\mathcal{C}$. Our approach combines the technology of spectral networks, which decomposes flat $GL(K,\\mathbb{C})$-connections on $\\mathcal{C}$ in terms of flat abelian connections on a $K$-fold cover of $\\mathcal{C}$, and the skein algebra in the 3-manifold $\\mathcal{C}\\times [0,1]$, which expresses the representation theory of the quantum group $U_q(gl_K)$. With any path on $\\mathcal{C}$, the quantum holonomy associates a positive Laurent polynomial in the quantized Fock-Goncharov coordinates of higher Teichm\\"uller space. This confirms various positivity conjectures in physics and mathematics.
Wall effects on the cross-buoyancy around a square cylinder in the steady regime
A. K. Dhiman
2012-06-01
Full Text Available The effects of blockage ratio on the combined free and forced convection from a long heated square obstacle confined in a horizontal channel are investigated in this work. The numerical computations are performed in the steady regime for Reynolds number = 1 - 30, Richardson number = 0 - 1 for blockage ratios of 0.125 and 0.25 for the fixed Prandtl number of 0.7 (air. The governing equations, along with appropriate boundary conditions, are solved by using a semi-explicit finite volume method implemented on the collocated grid arrangement. The total drag and lift coefficients, local and average Nusselt numbers and the representative streamline, vorticity and isotherm patterns are presented to elucidate the role of blockage ratio on the cross-buoyancy across a confined square cylinder. The asymmetry in the flow and temperature fields decreases with increasing value of the blockage ratio. Similar to forced convection, the total drag coefficient increases with increasing value of the blockage ratio for the fixed values of the Reynolds and Richardson numbers.
Domain Walls Zoo in Supersymmetric QCD
Smilga, A. V.; Veselov, A. I.
1997-01-01
Solving numerically the equations of motion for the effective lagrangian describing supersymmetric QCD with the SU(2) gauge group, we find a menagerie of complex domain wall solutions connecting different chirally asymmetric vacua. Some of these solutions are BPS saturated walls; they exist when the mass of the matter fields does not exceed some critical value m < m* < 4.67059... There are also sphaleron branches (saddle points of the ebergy functional). In the range m* < m < m** \\approx 4.83...
Writing Beyond the Wall: Translation, Cross-cultural Exchange, and Chen Ran's 'A Private Life'
Kay Schaffer
2006-09-01
Full Text Available The past decade has witnessed an unprecedented rise in the global flow of knowledge, nowhere more apparent in the exchange of ideas between China and modern western democracies. Our interest concerns one aspect of this global flow— the translation of Chinese women’s autobiographical writing into English. Taking Chen Ran’s A Private Life (English edition, 2004 as a point of departure, the paper explores issues of translingual practice and cross-cultural exchange. It considers what escapes or is lost in translation as well as the additive potential of the host text. It is sometimes the case that the translation can deliberately make certain ambiguities visible—whether from pragmatic, market-driven motivations or from more complex political, historical and cultural considerations. These negotiations of meaning that occur in the translation process can reverberate on the critical reception of texts in both the ‘guest’ and ‘host’ languages (Liu 1995, with open-ended, incomplete and indeterminate effects. The paper examines the effects of the omission of a brief parenthetical section of three paragraphs from one chapter of the Chinese edition of A Private Life. Yet, even that small emendation changes the original text as a cultural object and alters potential modes of its reception. In this case, the translation results in a loss of ambiguity, irony, philosophic and rhetorical sophistication while also offering additive potentials that enhance the generation of new meanings in the translingual exchange, here with reference Tiananmen and contemporary feminism in China. The translation process provides new channels for readers, writers and theorists to dialogue and communicate across gaps of difference, despite inhibiting factors like the imposition of local restraints, the universalising pressures of western modernity, and asymmetrical relations of power between guest and host language contexts.
The spacetime life of a non-BPS D-particle
We investigate the classical geometry generated by a stable non-BPS D-particle. We consider the boundary state of a stable non-BPS D-particle in the covariant formalism in the type IIB theory orbifolded by (-1)FL·I4. We calculate the scattering amplitude between two D-particles in the non-compact and compact orbifold and analyse the short and long distance behaviour. At short distances we find no force at order υ2 for any radius, and at the critical radius we find a BPS-like behaviour up to υ4 corrections for long and short distances. Projecting the boundary state on the massless states of the orbifold closed string spectrum we obtain the large distance behaviour of the classical solution describing this non-BPS D-particle in the non-compact and compact cases. By using the non-BPS D-particle as a probe of the background geometry of another non-BPS D-particle, we recover the no-force condition at the critical radius and the υ2 behaviour of the probe. Moreover, assuming that the no-force persists for the complete geometry we derive part of the classical solution for the non-BPS D-particle. (author)
Novel BPS Wilson loops in three-dimensional quiver Chern–Simons-matter theories
Hao Ouyang
2016-02-01
Full Text Available We show that generic three-dimensional N=2 quiver super Chern–Simons-matter theories admit Bogomol'nyi–Prasad–Sommerfield (BPS Drukker–Trancanelli (DT type Wilson loops. We investigate both Wilson loops along timelike infinite straight lines in Minkowski spacetime and circular Wilson loops in Euclidean space. In Aharnoy–Bergman–Jafferis–Maldacena theory, we find that generic BPS DT type Wilson loops preserve the same number of supersymmetries as Gaiotto–Yin type Wilson loops. There are several free parameters for generic BPS DT type Wilson loops in the construction, and supersymmetry enhancement for Wilson loops happens for special values of the parameters.
Clustering and decomposition for non BPS solutions of the $\\mathbb{CP}^{N-1}$ models
Bolognesi, S.; Zakrzewski, W.
2013-01-01
We look at solutions [both Bogomol’nyi-Prasad-Sommerfield (BPS) and non-BPS] of the CPN−1 model on R×S1 (with twisted boundary conditions), in particular by using a conformal mapping technique, and we show how to interpret these solutions by decomposing them into expressions describing constituent solitons. We point out the problems that may arise (for non-BPS solutions) when one naively looks at the clustering properties of these solutions. This could lead to misunderstandings when studying ...
Clustering and decomposition for non BPS solutions of the $\\mathbb{CP}^{N-1}$ models
Bolognesi, S
2013-01-01
We look at solutions (both BPS and non-BPS) of the $\\mathbb{CP}^{N-1}$ model on $\\mathbb{R} \\times S^1$ (with twisted boundary conditions), in particular by using a conformal mapping technique, and we show how to interpret these solutions by decomposing them into expressions describing constituent solitons. We point out the problems that may arise (for non-BPS solutions) when one naively looks at the clustering properties of these solutions. This could lead to misunderstandings when studying extrapolations between small and large compactification radii.
Clustering and decomposition for non-BPS solutions of the CPN -1 models
Bolognesi, S.; Zakrzewski, W.
2014-03-01
We look at solutions [both Bogomol'nyi-Prasad-Sommerfield (BPS) and non-BPS] of the CPN -1 model on R×S1 (with twisted boundary conditions), in particular by using a conformal mapping technique, and we show how to interpret these solutions by decomposing them into expressions describing constituent solitons. We point out the problems that may arise (for non-BPS solutions) when one naively looks at the clustering properties of these solutions. This could lead to misunderstandings when studying extrapolations between small and large compactification radii.
Cabellos, O. [Instituto de Fusion Nuclear, Universidad Politecnica de Madrid, Madrid (Spain)]. E-mail: cabellos@din.upm.es; Reyes, S. [Lawrence Livermore National Laboratory, Livermore, CA (United States); Sanz, J. [Instituto de Fusion Nuclear, Universidad Politecnica de Madrid, Madrid (Spain); University Nacional Educacion a Distancia, Dep. Ingenieria Energetica, Juan del Rosal 12, 28040 Madrid (Spain); Rodriguez, A. [University Nacional Educacion a Distancia, Dep. Ingenieria Energetica, Juan del Rosal 12, 28040 Madrid (Spain); Youssef, M. [University of California, Los Angeles, CA (United States); Sawan, M. [University of Wisconsin, Madison, WI (United States)
2006-02-15
A Monte Carlo procedure has been applied in this work in order to address the impact of activation cross-sections (XS) uncertainties on contact dose rate and decay heat calculations for the outboard first wall (FW) of a magnetic fusion energy (MFE) demonstration (DEMO) reactor. The XSs inducing the major uncertainty in the prediction of activation related quantities have been identified. Results have shown that for times corresponding to maintenance activities the uncertainties effect is insignificant since the dominant XSs involved in these calculations are based on accurate experimental data evaluations. However, for times corresponding to waste management/recycling activities, the errors induced by the XSs uncertainties, which in this case are evaluated using systematic models, must be considered. It has been found that two particular isotopes, {sup 6}Co and {sup 94}Nb, are key contributors to the global DEMO FW activation uncertainty results. In these cases, the benefit from further improvements in the accuracy of the critical reaction XSs is discussed.
The 1/2 BPS Wilson loop in ABJM theory at two loops
Bianchi, Marco S.; Giribet, Gaston; Leoni, Matias; Penati, Silvia
2013-01-01
We compute the expectation value of the 1/2 BPS circular Wilson loop in ABJM theory at two loops in perturbation theory. The result shows perfect agreement with the prediction from localization and the proposed framing factor.
Vortex-type half-BPS solitons in Aharony-Bergman-Jafferis-Maldacena theory
We study the Aharony-Bergman-Jafferis-Maldacena (ABJM) theory without and with mass deformation. It is shown that maximally supersymmetry preserving, D-term, and F-term mass deformations of single mass parameter are equivalent. We obtain vortex-type half-BPS equations and the corresponding energy bound. For the undeformed ABJM theory, the resulting half-BPS equation is the same as that in supersymmetric Yang-Mills theory and no finite energy regular BPS solution is found. For the mass-deformed ABJM theory, the half-BPS equations for U(2)xU(2) case reduce to the vortex equation in Maxwell-Higgs theory, which supports static regular multivortex solutions. In U(N)xU(N) case with N>2 the non-Abelian vortex equation of Yang-Mills-Higgs theory is obtained.
The Spacetime Life of a non-BPS D-particle
Eyras, E; Eyras, Eduardo; Panda, Sudhakar
2000-01-01
We investigate the classical geometry generated by a stable non-BPSD-particle. We consider the boundary state of a stable non-BPS D-particle inthe covariant formalism in the type IIB theory orbifolded by (-1)^{F_L} I_4.Projecting the boundary state on the massless states of the orbifold closedstring spectrum we obtain the large distance behaviour of the classicalsolution describing this non-BPS D-particle in the non-compact and compactcases. By using the non-BPS D-particle as a probe of the background geometry ofanother non-BPS D-particle, we recover the no-force condition at the criticalradius. Moreover, considering that the no-force persists at any distance fromthe source we derive part of the full classical solution for the non-BPSD-particle.
BPS Force Balances via Spin-Spin Interactions
Kastor, D A; Kastor, David; Traschen, Jennie
1999-01-01
We study two systems of BPS solitons in which spin-spin interactions are important in establishing the force balances which allow static, multi-soliton solutions to exist. Solitons in the Israel-Wilson-Perjes (IWP) spacetimes each carry arbitrary, classical angular momenta. Solitons in the Aichelburg-Embacher "superpartner" spacetimes carry quantum mechanical spin, which originates in the zero-modes of the gravitino field of N=2 supergravity in an extreme Reissner-Nordstrom background. In each case we find a cancellation between gravitational spin-spin and magnetic dipole-dipole forces, in addition to the usual one between Newtonian gravitational attraction and Coulombic electrostatic repulsion. In both cases, we analyze the forces between two solitons by treating one of the solitons as a probe or test particle, with the appropriate properties, moving in the background of the other. In the IWP case, the equation of motion for a spinning test particle, originally due to Papapetrou, includes a coupling between ...
BPS operators from the Wilson loop in the 3-dimensional supersymmetric Chern-Simons theory
Fujita, Mitsutoshi
2009-01-01
We consider the small deformation of the pointlike Wilson loop in the 3-dimensional N=6 superconformal Chern-Simons theory. By Taylor expansion of the pointlike Wilson loop in powers of the loop variables, we obtain the BPS operators that correspond to the excited string states of the dual IIA string theory on the pp wave background. The BPS conditions of the Wilson loop constrain both the loop variables and the forms of the operators obtained in the Taylor expansion.
Hatefi, Ehsan, E-mail: ehsanhatefi@gmail.com [Centre for Research in String Theory, School of Physics and Astronomy, Queen Mary University of London, Mile End Road, E1 4NS, London (United Kingdom); National Institute for Theoretical Physics, School of Physics, Mandelstam Institute for Theoretical Physics, University of the Witwatersrand, Wits, 2050, Johannesburg (South Africa); Institute des Hautes Etudes Scientifiques, 91440, Bures-sur-Yvette (France)
2015-10-31
From the world-sheet point of view we compute three, four and five point BPS and non-BPS scattering amplitudes of type IIA and IIB superstring theory. All these mixed S-matrix elements including a Ramond–Ramond closed string (RR) in the bulk and a scalar/gauge or tachyons with all different pictures (including an RR in asymmetric and symmetric pictures) have been carried out. We have also shown that in asymmetric pictures various equations must be kept fixed. More importantly, by direct calculations on the upper half plane, it is realised that some of the equations (which must be true) for BPS branes cannot be necessarily applied to non-BPS amplitudes. We also derive the S-matrix elements of 〈V{sub C}{sup -2}V{sub ϕ}{sup 0}V{sub A}{sup 0}V{sub T}{sup 0}〉 and clarify the fact that in the presence of the scalar field and an RR, the terms carrying momentum of an RR in the transverse directions play an important role in the entire form of the S-matrix and their presence is needed in order to have gauge invariance for the entire S-matrix elements of type IIA (IIB) superstring theory.
Hatefi, Ehsan [Queen Mary University of London, Centre for Research in String Theory, School of Physics and Astronomy, London (United Kingdom); University of the Witwatersrand, Wits, National Institute for Theoretical Physics, School of Physics, Mandelstam Institute for Theoretical Physics, Johannesburg (South Africa); Institute des Hautes Etudes Scientifiques, Bures-sur-Yvette (France)
2015-11-15
From the world-sheet point of view we compute three, four and five point BPS and non-BPS scattering amplitudes of type IIA and IIB superstring theory. All these mixed S-matrix elements including a Ramond-Ramond closed string (RR) in the bulk and a scalar/gauge or tachyons with all different pictures (including an RR in asymmetric and symmetric pictures) have been carried out. We have also shown that in asymmetric pictures various equations must be kept fixed. More importantly, by direct calculations on the upper half plane, it is realised that some of the equations (which must be true) for BPS branes cannot be necessarily applied to non-BPS amplitudes. We also derive the S-matrix elements of left angle V{sub C}{sup -2}V{sub φ}{sup 0}V{sub A}{sup 0}V{sub T}{sup 0} right angle and clarify the fact that in the presence of the scalar field and an RR, the terms carrying momentum of an RR in the transverse directions play an important role in the entire form of the S-matrix and their presence is needed in order to have gauge invariance for the entire S-matrix elements of type IIA (IIB) superstring theory. (orig.)
Effective action of domain wall networks
U(NC) gauge theory with NF fundamental scalars admits BPS junctions of domain walls. When the networks/webs of these walls contain loops, their size moduli give localized massless modes. We construct Kaehler potential of their effective action. In the large size limit Kaehler metric is well approximated by kinetic energy of walls and junctions, which is understood in terms of tropical geometry. Kaehler potential can be expressed in terms of hypergeometric functions that are useful to understand small size behavior. Even when the loop shrinks, the metric is regular with positive curvature. Moduli space of a single triangle loop has a geometry between a cone and a cigar
Flores, Aurea E; Chhatwal, G S; Hillier, Sharon L; Baker, Carol J; Ferrieri, Patricia
2014-12-01
Group B protective surface protein (BPS) is expressed on the cell surface of some group B streptococcal (GBS) (Streptococcus agalactiae) strains and adds to the identification by capsular polysaccharide (CPS), and c or R proteins. We investigated the prevalence of BPS among GBS clinical isolates (303 invasive, 4122 colonizing) collected over 11 years in four American cities. Hot HCl cell extracts were tested by immunoprecipitation in agarose with rabbit antisera to BPS; the alpha (α) and beta (β) components of c protein; R1, R3, and R4 species of R protein; and CPS serotypes Ia-VIII. BPS was found in 155 isolates (seven invasive, 148 colonizing). Of these, 87 were Ia, 37 II, 20 V; none were III. BPS was expressed usually with another protein: a species of R by 87 or a component of c by 39. The predominant CPS/protein profiles with BPS were Ia/R1,BPS and II/c(α + β),BPS. Thus, along with CPS serotype and other surface proteins, BPS can be a valuable marker for precise strain characterization of unique GBS clinical isolates with complex surface protein profiles. PMID:25108378
Emma Adhikari; Dong-Keun Lee; Patrick Giavalisco; Leslie E. Sieburth
2013-01-01
Root-to-shoot signaling is used by plants to coordinate shoot development with the conditions experienced by the roots.A mobile and biologically active compound,the bps signal,is over-produced in roots of an Arabidopsis thaliana mutant called bypass1 (bps1),and might also be a normally produced signaling molecule in wild-type plants.Our goal is to identify the bps signal chemically,which will then allow us to assess its production in normal plants.To identify any signaling molecule,a bioassay is required,and here we describe the development of a robust,simple,and quantitative bioassay for the bps signal.The developed bioassay follows the growth-reducing activity of the bps signal using the pCYCB1;1::GUS cell cycle marker.Wild-type plants carrying this marker,and provided the bps signal through either grafts or metabolite extracts,showed reduced cell division.By contrast,control grafts and treatment with control extracts showed no change in pCYCB1;1::GUS expression.To determine the chemical nature of the bps signal,extracts were treated with RNase A,Proteinase K,or heat.None of these treatments diminished the activity of bps1 extracts,suggesting that the active molecule might be a metabolite.This bioassay will be useful for future biochemical fractionation and analysis directed toward bps signal identification.
Evolution and functional diversity of the Calcium Binding Proteins (CaBPs
Lee P Haynes
2012-02-01
Full Text Available The mammalian central nervous system (CNS exhibits a remarkable ability to process, store and transfer information. Key to these activities is the use of highly regulated and unique patterns of calcium signals encoded by calcium channels and decoded by families of specific calcium-sensing proteins. The largest family of eukaryotic calcium sensors are those related to the small EF-hand containing protein calmodulin (CaM. In order to maximise the usefulness of calcium as a signalling species and to permit the evolution and fine tuning of the mammalian CNS, families of related proteins have arisen that exhibit characteristic calcium binding properties and tissue-, cellular- and sub-cellular distribution profiles. The Calcium Binding Proteins (CaBPs represent one such family of vertebrate specific calmodulin like proteins that have emerged in recent years as important regulators of essential neuronal target proteins. Bioinformatic analyses indicate that the CaBPs consist of two subfamilies and that the ancestral members of these are CaBP1 and CaBP8. The CaBPs have distinct intracellular localisations based on different targeting mechanisms including a novel type-II transmembrane domain in CaBPs 7 and 8. Recent work has led to the identification of new target interactions and possible functions for the CaBPs suggesting that they have multiple physiological roles with relevance for the normal functioning of the CNS.
On correlation functions of BPS operators in $3d$ $\\mathcal{N}=6$ superconformal theories
Liendo, Pedro; Mitev, Vladimir
2015-01-01
We introduce a novel harmonic superspace for $3d$ $\\mathcal{N}=6$ superconformal field theories that is tailor made for the study of correlation functions of BPS operators. We calculate a host of two- and three-point functions in full generality and put strong constraints on the form of four-point functions of some selected BPS multiplets. For the four-point function of $\\frac{1}{2}$-BPS operators we obtain the associated Ward identities by imposing the absence of harmonic singularities. The latter imply the existence of a solvable subsector in which the correlator becomes topological. This mechanism can be explained by cohomological reduction with respect to a special nilpotent supercharge.
6d → 5d → 4d reduction of BPS attractors in flat gauged supergravities
Kiril Hristov
2015-08-01
This is achieved starting from the BPS black string in 6d with an AdS3×S3 attractor and taking two different routes to arrive at a 1/2 BPS AdS2×S2 attractor of a non-BPS black hole in 4d N=2 flat gauged supergravity. The two inequivalent routes interchange the order of KK reduction on AdS3 and SS reduction on S3. We also find the commutator between the two operations after performing a duality transformation: on the level of the theory the result is the exchange of electric with magnetic gaugings; on the level of the solution we find a flip of the quartic invariant I4 to −I4.
A Tale of Two Spaces: BPS Wilson Loops in Minkowski Spacetime and Euclidean Space
Ouyang, Hao; Zhang, Jia-ju
2015-01-01
We discuss BPS Wilson loops of $d=4$ $\\mathcal N=4$ super Yang-Mills theory, $d=3$ $\\mathcal N=2$ super Chern-Simons-matter theory, and $d=3$ $\\mathcal N=6$ Aharony-Bergman-Jafferis-Maldacena theory, in both Minkowski spacetime and Euclidean space. We find that there are timelike and null BPS Wilson loops in Minkowski spacetime, but spacelike BPS Wilson loops do not exist. We attribute this to the conflicts of reality conditions of spinors. However, in Euclidean space spacelike Wilson loops do exist. There are both Wilson lines of infinite straight lines and Wilson loops of circles. This is because the reality conditions of spinors are lost after Wick rotation. The result is reasonable in view of AdS/CFT correspondence.
Construction of novel BPS Wilson loops in three-dimensional quiver Chern-Simons-matter theories
Ouyang, Hao; Zhang, Jia-ju
2015-01-01
In this paper, we construct novel Drukker-Trancanelli (DT) type BPS Wilson loops along infinite straight lines in $\\mathcal N=2,3$ quiver super Chern-Simons-matter (CSM) theories, Aharony-Bergman-Jafferis-Maldacena (ABJM) theory, and $\\mathcal N=4$ orbifold ABJM theory. There are several free complex parameters in the DT type BPS Wilson loops, and for Wilson loops in ABJM theory and $\\mathcal N=4$ orbifold ABJM theory there are supersymmetry enhancements at special values of the parameters. We check that the differences of the DT type and Gaiotto-Yin (GY) type Wilson loops are $Q$-exact with $Q$ being some supercharges preserved by both the DT type and GY type Wilson loops. The results would be useful to calculate vacuum expectation values of the Wilson loops in matrix models if they are still BPS quantum mechanically.
Split attractor flows and the spectrum of BPS D-branes on the Quintic
Denef, F; Raugas, M V; Denef, Frederik; Greene, Brian; Raugas, Mark
2001-01-01
We investigate the spectrum of type IIA BPS D-branes on the quintic from a four dimensional supergravity perspective and the associated split attractor flow picture. We obtain some very concrete properties of the (quantum corrected) spectrum, mainly based on an extensive numerical analysis, and to a lesser extent on exact results in the large radius approximation. We predict the presence and absence of some charges in the BPS spectrum in various regions of moduli space, including the precise location of the lines of marginal stability and the corresponding decay products. We explain how the generic appearance of multiple basins of attraction is due to the presence of conifold singularities and give some specific examples of this phenomenon. Some interesting space-time features of these states are also uncovered, such as a nontrivial, moduli independent lower bound on the area of the core of arbitrary BPS solutions, whether they are black holes, empty holes, or more complicated composites.
Three-Charge Black Holes and Quarter BPS States in Little String Theory
Giveon, Amit; Kutasov, David; Lee, Sungjay
2015-01-01
We show that the system of $k$ NS5-branes wrapping $\\mathbb{T}^4\\times S^1$ has non-trivial vacuum structure. Different vacua have different spectra of 1/4 BPS states that carry momentum and winding around the $S^1$. In one vacuum, such states are described by black holes; in another, they can be thought of as perturbative BPS states in Double Scaled Little String Theory. In general, both kinds of states are present. We compute the degeneracy of perturbative BPS states exactly, and show that it differs from that of the corresponding black holes. We comment on the implication of our results to the black hole microstate program, UV/IR mixing in Little String Theory, string thermodynamics, the string/black hole transition, and other issues.
Split attractor flows and the spectrum of BPS D-branes on the Quintic
We investigate the spectrum of type IIA BPS D-branes on the quintic from a four dimensional supergravity perspective and the associated split attractor flow picture. We obtain some very concrete properties of the (quantum corrected) spectrum, mainly based on an extensive numerical analysis, and to a lesser extent on exact results in the large radius approximation. We predict the presence and absence of some charges in the BPS spectrum in various regions of moduli space, including the precise location of the lines of marginal stability and the corresponding decay products. We explain how the generic appearance of multiple basins of attraction is due to the presence of conifold singularities and give some specific examples of this phenomenon. Some interesting space-time features of these states are also uncovered, such as a nontrivial, moduli independent lower bound on the area of the core of arbitrary BPS solutions, whether they are black holes, empty holes, or more complicated composites. (author)
Monopole dynamics and BPS dyons in N=2 super-Yang-Mills theories
We determine the low-energy dynamics of monopoles in pure N=2 Yang-Mills theories for points in the vacuum moduli space where the two Higgs fields are not aligned. The dynamics is governed by a supersymmetric quantum mechanics with potential terms and four real supercharges. The corresponding superalgebra contains a central charge but nevertheless supersymmetric states preserve all four supercharges. The central charge depends on the sign of the electric charges and consequently so does the BPS spectrum. We focus on the SU(3) case where certain BPS states are realized as zero modes of a Dirac operator on Taub-NUT space twisted by the triholomorphic Killing vector field. We show that the BPS spectrum includes hypermultiplets that are consistent with the strong- and weak-coupling behavior of Seiberg-Witten theory. (c) 2000 The American Physical Society
New Massive Gravity Domain Walls
dS, U Camara
2010-01-01
The properties of the asymptotic $AdS_3$ space-times representing flat domain walls (DW's) solutions of the New Massive 3D Gravity with scalar matter are studied. Our analysis is based on $I^{st}$ order BPS-like equations involving an appropriate superpotential. The Brown-York boundary stress-tensor is used for the calculation of DW's tensions as well as of the $CFT_2$'s central charges. The holographic renormalization group flows and the phase transitions in specific deformed $CFT_2$ dual to 3D massive gravity model with quadratic superpotential are discussed.
Bubbling 1/4 BPS solutions in type IIB and supergravity reductions on SnxSn
We extend the construction of bubbling 1/2 BPS solutions of Lin, Lunin and Maldacena (H. Lin, O. Lunin, J. Maldacena, JHEP 0410 (2004) 025, hep-th/0409174) in two directions. First we enquire whether bubbling 1/2 BPS solutions can be constructed in minimal 6d supergravity and second we construct solutions that are 1/4 BPS in type IIB. We find that the S1xS1 bosonic reduction of (1,0) 6d supergravity to 4d gravity coupled to 2 scalars and a gauge field is consistent only provided that the gauge field obeys a constraint (F-bar F=0). This is to be contrasted to the case of the S3xS3 bosonic reduction of type IIB supergravity to 4d gravity, 2 scalars and a gauge field, where consistency is achieved without imposing any such constraints. Therefore, in the case of (1,0) 6d supergravity we are able to construct 1/2 BPS solutions, similar to those derived in type IIB, provided that this additional constraint is satisfied. This ultimately prohibits the construction of a family of 1/2 BPS solutions corresponding to a bubbling AdS3xS3 geometry. Returning to type IIB solutions, by turning on an axion-dilaton field we construct a family of bubbling 1/4 BPS solutions. This corresponds to the inclusion of back-reacted D7 branes to the solutions of Lin, Lunin and Maldacena
BPS operators from the Wilson loop in the 3-dimensional supersymmetric Chern-Simons theory
Fujita, Mitsutoshi
2009-01-01
We consider the small deformation of the point-like Wilson loop in the 3-dimensional $\\mathcal{N}=6$ superconformal Chern-Simons theory. By Taylor expansion of the point-like Wilson loop in powers of the loop variables, we obtain the BPS operators that correspond to the excited string states of the dual IIA string theory on the pp wave background. The BPS conditions of the Wilson loop constrain both the loop variables and the forms of the operators obtained in the Taylor expansion.
BPS Wilson loops and Bremsstrahlung function in ABJ(M): a two loop analysis
Bianchi, M; Griguolo, L.; de Leoni, M. (Massimiliano); Penati, S; Seminara, D.
2014-01-01
We study a family of circular BPS Wilson loops in $ \\mathcal{N} $ = 6 super Chern-Simons-matter theories, generalizing the usual 1/2-BPS circle. The scalar and fermionic couplings depend on two deformation parameters and these operators can be considered as the ABJ(M) counterpart of the DGRT latitudes defined in $ \\mathcal{N} $ = 4 SYM. We perform a complete two-loop analysis of their vacuum expectation value, discuss the appearance of framing-like phases and propose a general relation with c...
Rotational-vibrational coupling in the BPS Skyrme model of baryons
Adam, C; Sanchez-Guillen, J; Wereszczynski, A
2013-01-01
We calculate the rotational-vibrational spectrum in the BPS Skyrme model for the hedgehog skyrmion with baryon number one. The resulting excitation energies for the nucleon and delta Roper resonances are slightly above their experimental values. Together with the fact that in the standard Skyrme model these excitation energies are significantly lower than the experimental ones, this provides strong evidence for the conjecture that the inclusion of the BPS Skyrme model is necessary for a successful quantitative description of physical properties of baryons and nuclei.
Rotational-vibrational coupling in the BPS Skyrme model of baryons
Adam, C.; Naya, C.; Sanchez-Guillen, J. [Departamento de Física de Partículas, Universidad de Santiago de Compostela and Instituto Galego de Física de Altas Enerxias (IGFAE), E-15782 Santiago de Compostela (Spain); Wereszczynski, A. [Institute of Physics, Jagiellonian University, Reymonta 4, Kraków (Poland)
2013-11-04
We calculate the rotational-vibrational spectrum in the BPS Skyrme model for the hedgehog skyrmion with baryon number one. The resulting excitation energies for the nucleon and delta Roper resonances are slightly above their experimental values. Together with the fact that in the standard Skyrme model these excitation energies are significantly lower than the experimental ones, this provides strong evidence for the conjecture that the inclusion of the BPS Skyrme model is required for a successful quantitative description of physical properties of baryons and nuclei.
BPS Equations in Omega-deformed N=4 Super Yang-Mills Theory
Ito, Katsushi; Nakajima, Hiroaki; Sasaki, Shin
2015-01-01
We study supersymmetry of N=4 super Yang-Mills theory in four dimensions deformed in the Omega-background. We take the Nekrasov-Shatashvili limit of the background so that two-dimensional super Poincare symmetry is recovered. We compute the deformed central charge of the superalgebra and study the 1/2 and 1/4 BPS states. We obtain the Omega-deformed 1/2 and 1/4 BPS dyon equations from the deformed supersymmetry transformation and the Bogomol'nyi completion of the energy.
On Toda equation and half BPS supergravity solution in M-theory
Recently, it was shown that half BPS Supergravity solution of theories with SU(2/4) symmetry algebra is given uniformly by determining a single function which obeys three dimensional continuous Toda equation. In this paper, we study the scale invariant solution of Toda equation. Our motivation is that some solutions of half BPS sector of IIB supergravity, as one excepts from the fermion description of the theory, are scale invariant. By defining two auxiliary functions we prove that such solutions of Toda equation obey cubic algebraic equation. We obtain some simpl solutions of Toda equation specially, we observe that the PP-wave solution can be written in this fashion
Non-BPS interactions from the type II one loop four graviton amplitude
Basu, Anirban
2016-06-01
We obtain T-duality invariant second order differential equations satisfied by the {D}8{{ R }}4 and {D}10{{ R }}4 interactions from the low energy expansion of the one loop four graviton amplitude in toroidally compactified type II string theory. The eigenvalues of these equations are completely determined by the structure of the one loop integrands. Unlike the BPS interactions, these non-BPS interactions satisfy Poisson equations having source terms that receive contributions from both the bulk and boundary of the worldsheet moduli space. We explicitly solve these equations in nine-dimensions.
Baryon chemical potential and in-medium properties of BPS skyrmions
Adam, C; Naya, C; Sanchez-Guillen, J; Vazquez, R; Wereszczynski, A
2015-01-01
We continue the investigation of thermodynamical properties of the BPS Skyrme model. In particular, we analytically compute the baryon chemical potential both in the full field theory and in a mean-field approximation. In the full field theory case, we find that the baryon chemical potential is always exactly proportional to the baryon density, for arbitrary solutions. We further find that, in the mean-field approximation, the BPS Skyrme model approaches the Walecka model in the limit of high density - their thermodynamical functions as well as the equation of state agree in this limit. This fact allows to read off some properties of the $\\omega$-meson from the BPS Skyrme action, even though the latter model is entirely based on the (pionic) $SU(2)$ Skyrme field. On the other hand, at low densities, at the order of the usual nuclear matter density, the equations of state of the two models are no longer universal, such that a comparison depends on some model details. Still, also the BPS Skyrme model gives rise...
y-Deformed BPS Dp-branes On a Surface In a Calabi-Yau Threefold
Ospina, J F
2000-01-01
Using y-deformed algebraic geometric techniques the y-deformed Mukay vector of RR-charges of the y-deformed BPS Dp-branes localized on a surface in a Calabi-Yau threefold. The formulas that are obtained here are generalizations of the formulas of the fourth section of the preprint hep-th/0007243 .
Cosmic D- and DF-strings from D3Dbar3: Black Strings and BPS Bound
Kim, T; Kyae, B; Lee, J; Kim, Taekyung; Kim, Yoonbai; Kyae, Bumseok; Lee, Jungjai
2006-01-01
We study D- and DF-strings from D3${\\bar {\\rm D}}3$ in the context of Dirac-Born-Infeld type effective field theory. In the presence of an electric flux from a transverse direction, gravitating thick D-string solutions form a spatial manifold, ${\\rm S}^{2}\\times {\\rm R}^{1}$, and straight D-strings stretched along the R${}^{1}$ direction are located at the south and north poles of the two-sphere. There is a horizon along its equator and then the structure of black strings is supported. We also discuss systematic derivation of the BPS bounds for thin parallel D- and DF-strings in both flat and curved spacetime. The BPS sum rule is obtained for arbitrarily-separated multi-string configuration under a Gaussian type tachyon potential and, at the site of each thin BPS D(F)-string, the pressure does not vanish but is finite. For the conical geometry induced by thin BPS D- and DF-strings, we find that there exists maximum deficit angle $\\pi$.
Rossi, Dolene; van Rensburg, Henriette; Clark, Damien; Harreveld, R. E.; Beer, Colin; Danaher, P. A.
2015-01-01
The article on which this paper reflects ["Exploring a Cross-Institutional Research Collaboration and Innovation: Deploying Social Software and Web 2.0 Technologies to Investigate Online Learning Designs and Interactions in Two Australian Universities"] presented elements of a research project investigating learning interactions in…
Dominis Prester, Predrag; Terzić, Tomislav
2008-12-01
We calculate near-horizon solutions for four-dimensional 4-charge and five-dimensional 3-charge black holes in heterotic string theory from the part of the ten-dimensional tree-level effective action which is connected to gravitational Chern-Simons term by supersymmetry. We obtain that the entropies of large black holes exactly match the α'-exact statistical entropies obtained from microstate counting (D = 4) and AdS/CFT correspondence (D = 5). Especially interesting is that we obtain agreement for both BPS and non-BPS black holes, contrary to the case of R2-truncated (four-derivative) actions (D-dimensional Script N = 2 off-shell supersymmetric or Gauss-Bonnet) were used, which give the entropies agreeing (at best) just for BPS black holes. The key property of the solutions, which enabled us to tackle the action containing infinite number of terms, is vanishing of the Riemann tensor bar RMNPQ obtained from torsional connection defined with barGamma = Γ-½H. Moreover, if every monomial of the remaining part of the effective action would contain at least two Riemanns bar RMNPQ, it would trivially follow that our solutions are exact solutions of the full heterotic effective action in D = 10. The above conjecture, which appeared (in this or stronger form) from time to time in the literature, has controversial status, but is supported by the most recent calculations of Richards (arXiv:0807.3453 [hep-th]). Agreement of our results for the entropies with the microscopic ones supports the conjecture. As for small black holes, our solutions in D = 5 still have singular horizons.
Highlights: ► Diamines were used for one-step functionalization of nanotubes and nanodiamond. ► We found experimental evidences of cross-linking effects in these nanomaterials. ► We found a strong orientation effect in the functionalized carbon nanotubes. - Abstract: The covalent functionalization of carbon nanomaterials with diamines is a way to enhance the mechanical strength of nanocomposites due to cross-linking effects, to form complex networks for nanotube-based electronic circuits, as well as is important for a number of biomedical applications. The main goal of the present work was to covalently functionalize pristine multi-walled carbon nanotubes and nanodiamond with three aliphatic diamines (1,8-diaminooctane, 1,10-diaminodecane and 1,12-diaminododecane) and one aromatic diamine (1,5-diaminonaphthalene), by employing a simple one-step solvent-free methodology, which is based on thermal instead of chemical activation. We looked for experimental evidences of cross-linking effects in the carbon nanomaterials synthesized by using solubility/dispersibility tests, atomic force microscopy, scanning and transmission electron microscopy, as well as Fourier-transform infrared spectroscopy and thermogravimetric analysis for additional characterization.
Mohamad Al Ali
2014-02-01
Full Text Available Part 1 of the paper presents fundamental information about the experimental and theoretical research oriented to determine the resistance of thin-walled cold-formed compressed steel members with closed cross-sections, [1]. The investigated members were made from homogeneous material. The theoretical analysis was oriented to determine the resistance of mentioned members according to European and Slovak standards, while the experimental investigation was to verify the theoretical results and to investigate the behavior of the above-mentioned members during the loading process, [2]. Part 2 is focused on the numerical analysis of the achieved results, as well as on 3D modeling and simulation of the experimental tests.
The Hodge-elliptic genus, spinning BPS states, and black holes
Kachru, Shamit
2016-01-01
We perform a refined count of BPS states in the compactification of M-theory on $K3 \\times T^2$, keeping track of the information provided by both the $SU(2)_L$ and $SU(2)_R$ angular momenta in the $SO(4)$ little group. Mathematically, this four variable counting function may be expressed via the motivic Donaldson-Thomas counts of $K3 \\times T^2$, simultaneously refining Katz, Klemm, and Pandharipande's motivic Donaldson-Thomas counts on $K3$ and Oberdieck-Pandharipande's Gromov-Witten counts on $K3 \\times T^2$. This provides the first full answer for motivic curve counts of a compact Calabi-Yau threefold. Along the way, we develop a Hodge-elliptic genus for Calabi-Yau manifolds -- a new counting function for BPS states that interpolates between the Hodge polynomial and the elliptic genus of a Calabi-Yau.
BPS-saturated string amplitudes: K3 elliptic genus and Igusa cusp form χ10
We study BPS-saturated one-loop amplitudes in type II string theory compactified on K3×T2. The classes of amplitudes we consider are only sensitive to the very basic topological data of the internal K3 manifold. As a consequence, the integrands of the former are related to the elliptic genus of K3, which can be decomposed into representations of the internal N=4 superconformal algebra. Depending on the precise choice of external states these amplitudes capture either only the contribution of the short multiplets or the full series including intermediate multiplets. In the latter case we can define a generating functional for the whole class, which we show is given by the weight ten Igusa cusp form χ10 of Sp(4,Z). We speculate on possible algebraic implications of our result on the BPS states of the N=4 type II compactification.
Phase transitions and statistical mechanics for BPS Black Holes in AdS/CFT
Using the general framework developed in hep-th/0607056, we study in detail the phase space of BPS Black Holes in AdS, for the case where all three electric charges are equal. Although these solitons are supersymmetric with zero Hawking temperature, it turns out that these Black Holes have rich phase structure with sharp phase transitions associated to a corresponding critical generalized temperature. We are able to rewrite the gravity variables in terms of dual CFT variables and compare the gravity phase diagram with the free dual CFT phase diagram. In particular, the elusive supergravity constraint characteristic of these Black Holes is particularly simple and in fact appears naturally in the dual CFT in the definition of the BPS Index. Armed with this constraint, we find perfect match between BH and free CFT charges up to expected constant factors
AdS3 Holography for 1/4 and 1/8 BPS geometries
Giusto, Stefano; Russo, Rodolfo
2015-01-01
Recently a new class of 1/8-BPS regular geometries in type IIB string theory was constructed in arXiv:1502.01254. In this paper we provide a precise description of the semiclassical states dual, in the AdS/CFT sense, to these geometries. In explicit examples we show that the holographic 1-point functions and the Ryu-Takayanagi's Entanglement Entropy for a single small interval match the corresponding CFT calculations performed by using the proposed dual states. We also discuss several new examples of such precision holography analysis in the 1/4-BPS sector and provide an explicit proof that the small interval derivation of the Entanglement Entropy used in arXiv:1405.6185 is fully covariant.
BPS M5-branes as Defects for the 3d-3d Correspondence
Bah, Ibrahima; Halmagyi, Nick
2014-01-01
We study supersymmetric probe M5-branes in the AdS_4 solution that arises from M5-branes wrapped on a hyperbolic 3-manifold M_3. This amounts to introducing internal defects within the framework of the 3d-3d correspondence. The BPS condition for a probe M5-brane extending along all of AdS_4 requires it to wrap a surface embedded in an S^2-fibration over M_3. We find that the projection of this surface to M_3 can be either a geodesic or a tubular surface around a geodesic. These configurations preserve an extra U(1) symmetry, in addition to the one corresponding to the R-symmetry of the dual 3d N=2 gauge theory. BPS M2-branes can stretch between M5-branes wrapping geodesics. We interpret the addition of probe M5-branes on a closed geodesic in terms of conformal Dehn surgery.
Instanton Corrections of 1/6 BPS Wilson Loops in ABJM Theory
Okuyama, Kazumi
2016-01-01
We study instanton corrections to the vacuum expectation value (VEV) of 1/6 BPS Wilson loops in ABJM theory from the Fermi gas approach. We mainly consider Wilson loops in the fundamental representation and winding Wilson loops, but we also initiate the study of Wilson loops with two boundaries. We find that the membrane instanton corrections to the Wilson loop VEV are determined by the refined topological string in the Nekrasov-Shatashvili limit, and the pole cancellation mechanism between m...
Dissecting zero modes and bound states on BPS vortices in Ginzburg-Landau superconductors
Alonso-Izquierdo, Alberto; Guilarte, Juan Mateos
2016-01-01
In this paper the zero modes of fluctuation of cylindrically symmetric self-dual vortices are analyzed and described in full detail. These BPS topological defects arise at the critical point between Type II and Type I superconductors, or, equivalently, when the masses of the Higgs particle and the vector boson in the Abelian Higgs model are equal. In addition, novel bound states of Higss and vector bosons trapped by the self-dual vortices at their core are found and investigated.
Non-BPS Solutions of the Noncommutative CP^1 Model in 2+1 Dimensions
Furuta, Ko; Inami, Takeo(Mathematical Physics Lab., Riken Nishina Center, Saitama 351-0198, Japan); Nakajima, Hiroaki; Yamamoto, Masayoshi
2002-01-01
We find non-BPS solutions of the noncommutative CP^1 model in 2+1 dimensions. These solutions correspond to soliton anti-soliton configurations. We show that the one-soliton one-anti-soliton solution is unstable when the distance between the soliton and the anti-soliton is small. We also construct time-dependent solutions and other types of solutions.
Jung Hans-Joachim G
2010-05-01
Full Text Available Abstract Background The GeneChip® Medicago Genome Array, developed for Medicago truncatula, is a suitable platform for transcript profiling in tetraploid alfalfa [Medicago sativa (L. subsp. sativa]. However, previous research involving cross-species hybridization (CSH has shown that sequence variation between two species can bias transcript profiling by decreasing sensitivity (number of expressed genes detected and the accuracy of measuring fold-differences in gene expression. Results Transcript profiling using the Medicago GeneChip® was conducted with elongating stem (ES and post-elongation stem (PES internodes from alfalfa genotypes 252 and 1283 that differ in stem cell wall concentrations of cellulose and lignin. A protocol was developed that masked probes targeting inter-species variable (ISV regions of alfalfa transcripts. A probe signal intensity threshold was selected that optimized both sensitivity and accuracy. After masking for both ISV regions and previously identified single-feature polymorphisms (SFPs, the number of differentially expressed genes between the two genotypes in both ES and PES internodes was approximately 2-fold greater than the number detected prior to masking. Regulatory genes, including transcription factor and receptor kinase genes that may play a role in development of secondary xylem, were significantly over-represented among genes up-regulated in 252 PES internodes compared to 1283 PES internodes. Several cell wall-related genes were also up-regulated in genotype 252 PES internodes. Real-time quantitative RT-PCR of differentially expressed regulatory and cell wall-related genes demonstrated increased sensitivity and accuracy after masking for both ISV regions and SFPs. Over 1,000 genes that were differentially expressed in ES and PES internodes of genotypes 252 and 1283 were mapped onto putative orthologous loci on M. truncatula chromosomes. Clustering simulation analysis of the differentially expressed genes
Non-BPS exact solutions and their relation to bions in ${\\mathbb C}P^{N-1}$ models
Misumi, Tatsuhiro; Sakai, Norisuke
2016-01-01
We investigate non-BPS exact solutions in ${\\mathbb C}P^{N-1}$ sigma models on ${\\mathbb R}^1 \\times S^{1}$ with twisted boundary conditions, by using the Din-Zakrzewski projection method. We focus on the relation of the non-BPS solutions to the ansatz of multi-instanton (bion) configurations and discuss their significance in the context of the resurgence theory. We find that the transition between seemingly distinct configurations of multi-instantons occur as moduli changes in the non-BPS solutions, and the simplest non-BPS exact solution corresponds to multi-bion configurations with fully-compressed double fractional instantons in the middle. It indicates that the non-BPS solutions make small but nonzero contribution to the resurgent trans-series as special cases of the multi-bion configurations. We observe a generic pattern of transitions between distinct multi-bion configurations (flipping partners), leading to the three essential properties of the non-BPS exact solution: (i) opposite sign for terms corre...
Calculating corrections in F-theory from refined BPS invariants and backreacted geometries
This thesis presents various corrections to F-theory compactifications which rely on the computation of refined Bogomol'nyi-Prasad-Sommerfield (BPS) invariants and the analysis of backreacted geometries. Detailed information about rigid supersymmetric theories in five dimensions is contained in an index counting refined BPS invariants. These BPS states fall into representations of SU(2)L x SU(2)R, the little group in five dimensions, which has an induced action on the cohomology of the moduli space of stable pairs. In the first part of this thesis, we present the computation of refined BPS state multiplicities associated to M-theory compactifications on local Calabi-Yau manifolds whose base is given by a del Pezzo or half K3 surface. For geometries with a toric realization we use an algorithm which is based on the Weierstrass normal form of the mirror geometry. In addition we use the refined holomorphic anomaly equation and the gap condition at the conifold locus in the moduli space in order to perform the direct integration and to fix the holomorphic ambiguity. In a second approach, we use the refined Goettsche formula and the refined modular anomaly equation that govern the (refined) genus expansion of the free energy of the half K3 surface. By this procedure, we compute the refined BPS invariants of the half K3 from which the results of the remaining del Pezzo surfaces are obtained by flop transitions and blow-downs. These calculations also make use of the high symmetry of the del Pezzo surfaces whose homology lattice contains the root lattice of exceptional Lie algebras. In cases where both approaches are applicable, we successfully check the compatibility of these two methods. In the second part of this thesis, we apply the results obtained from the calculation of the refined invariants of the del Pezzo respectively the half K3 surfaces to count non-perturbative objects in F-theory. The first application is given by BPS states of the E-String which are
Calculating corrections in F-theory from refined BPS invariants and backreacted geometries
Poretschkin, Maximilian
2015-07-01
This thesis presents various corrections to F-theory compactifications which rely on the computation of refined Bogomol'nyi-Prasad-Sommerfield (BPS) invariants and the analysis of backreacted geometries. Detailed information about rigid supersymmetric theories in five dimensions is contained in an index counting refined BPS invariants. These BPS states fall into representations of SU(2){sub L} x SU(2){sub R}, the little group in five dimensions, which has an induced action on the cohomology of the moduli space of stable pairs. In the first part of this thesis, we present the computation of refined BPS state multiplicities associated to M-theory compactifications on local Calabi-Yau manifolds whose base is given by a del Pezzo or half K3 surface. For geometries with a toric realization we use an algorithm which is based on the Weierstrass normal form of the mirror geometry. In addition we use the refined holomorphic anomaly equation and the gap condition at the conifold locus in the moduli space in order to perform the direct integration and to fix the holomorphic ambiguity. In a second approach, we use the refined Goettsche formula and the refined modular anomaly equation that govern the (refined) genus expansion of the free energy of the half K3 surface. By this procedure, we compute the refined BPS invariants of the half K3 from which the results of the remaining del Pezzo surfaces are obtained by flop transitions and blow-downs. These calculations also make use of the high symmetry of the del Pezzo surfaces whose homology lattice contains the root lattice of exceptional Lie algebras. In cases where both approaches are applicable, we successfully check the compatibility of these two methods. In the second part of this thesis, we apply the results obtained from the calculation of the refined invariants of the del Pezzo respectively the half K3 surfaces to count non-perturbative objects in F-theory. The first application is given by BPS states of the E
SUSY QM from three domain walls in a scalar potential
We investigate the linear classical stability of Bogomol'nyi-Prasad-Sommerfield (BPS) on three domain wall solutions in a system of three coupled real scalar fields, for a general positive potential with a square form. From a field theoretic superpotential evaluated on the domain states, the connection between the supersymmetric quantum mechanics involving three-component eigenfunctions and the stability equation associated with three classical configurations is elaborated. (author)
Ma, Deyou; Yang, Hongsheng; Sun, Lina
2014-12-01
Sea cucumber ( Apostichopus japonicus) is one of the most important aquaculture animals in China. Usually its normal body color is black that fits its living environment. The juvenile individuals obtained by crossing albino sea cucumber segregated in body color. To document the transcriptome difference between albino associating sea cucumber and the control, we sequenced their transcriptomes with RNA-seq. Approximately, 4.790 million (M) and 4.884 M reads, 200 nt in length, were generated from the body wall of albino associating sea cucumber and the control, respectively, from them, 9550 (46.81%) putative genes were identified. In total, 583 genes were found to express differentially between albino associating sea cucumber and the control. Of these differentially expressed genes (DEGs), 4.8% changed more than five-folds. The expression levels of eight DEGs were confirmed with real-time PCR. The changing trend of these DEGs detected with real-time PCR agreed well with that detected with RNA-seq, although the change degree of some DEGs was different. Four significantly enriched pathways were identified for DEGs, which included phagocytosis, Staphylococcus aureus infection, ECM-receptor interaction and focal adhesion. These pathways were helpful for understanding the physiological difference between albino associating sea cucumber and the control.
Effective Action of Domain Wall Networks
Eto, M; Nagashima, T; Nitta, M; Ohashi, K; Sakai, N; Eto, Minoru; Fujimori, Toshiaki; Nagashima, Takayuki; Nitta, Muneto; Ohashi, Keisuke; Sakai, Norisuke
2007-01-01
U(Nc) gauge theory with Nf fundamental scalars admits BPS junctions of domain walls. When the networks/webs of these walls contain loops, their size moduli give localized massless modes. We construct K\\"ahler potential of their effective action. In the large size limit K\\"ahler metric is well approximated by kinetic energy of walls and junctions, which is understood in terms of tropical geometry. K\\"ahler potential can be expressed in terms of hypergeometric functions which are useful to understand small size behavior. Even when the loop shrinks, the metric is regular with positive curvature. Moduli space of a single triangle loop has a geometry between a cone and a cigar.
Developing a dynamic website using WordPress CMS for BPS Finland Oy
K.C., Kiran
2014-01-01
This Bachelor’s thesis aims to develop a website for a small-to-medium-sized enterprise (SME), BPS Finland Oy, which is fully based on the customer’s requirements. In this thesis project, a completely new dynamic website was developed from the design layout provided by the case company in a Photoshop version. WordPress, a Content Management System (CMS), was used to create a dynamic website. CMS is a software programme to power, manage and modify the website’s contents and avoid the need ...
Instanton Corrections of 1/6 BPS Wilson Loops in ABJM Theory
Okuyama, Kazumi
2016-01-01
We study instanton corrections to the vacuum expectation value (VEV) of 1/6 BPS Wilson loops in ABJM theory from the Fermi gas approach. We mainly consider Wilson loops in the fundamental representation and winding Wilson loops, but we also initiate the study of Wilson loops with two boundaries. We find that the membrane instanton corrections to the Wilson loop VEV are determined by the refined topological string in the Nekrasov-Shatashvili limit, and the pole cancellation mechanism between membrane instantons and worldsheet instantons works also in the Wilson loop VEVs as in the case of the partition functions.
Diagonal Form Factors and Hexagon Form Factors II. Non-BPS Light Operator
Jiang, Yunfeng
2016-01-01
We study the asymptotic volume dependence of the heavy-heavy-light three-point functions in the $\\mathcal{N}=4$ Super-Yang-Mills theory using the hexagon bootstrap approach, where the volume is the length of the heavy operator. We extend the analysis of our previous short letter 1511.06199 to the general case where the heavy operators can be in any rank one sector and the light operator being a generic non-BPS operator. We prove the conjecture of Bajnok, Janik and Wereszczynski 1404.4556 up to leading finite size corrections.
Self-intersection number of BPS junctions in backgrounds of three and seven-branes
In a recent paper DeWolfe et al. have shown how to use the self-intersection number of junctions to constrain the BPS spectrum of N=2, D=4 theories with ADE flavor symmetry arising on a single D3-brane probe in a 7-brane background. Motivated by the existence of more general N=2, D=4 theories arising on the worldvolume of multiple D3-brane probes we show how to compute the self-intersection number of junctions in the presence of 7-branes and multiple D3-branes. (author)
Half BPS states in AdS_5 x Y^{p,q}
Gava, Edi; Narain, Kumar S.; Milanesi, Giuseppe; O'Loughlin, Martin
2007-01-01
We study a class of solutions of IIB Supergravity which are asymptotically AdS_5 x Y^{p,q}. They have an R x SO(4) x SU(2) x U(1) isometry and preserve half of the 8 supercharges of the background geometry. They are described by a set of second order differential equations that we have found and analysed in a previous paper, where we studied 1/8 BPS states in the maximally supersymmetric AdS_5 x S^5 background. These geometries correspond to certain chiral primary operators of the N=1 superco...
Collisions of domain walls in a supersymmetric model
A collision of two parallel domain walls in a supersymmetric model is analyzed by using both the effective-Lagrangian approximation and a numerical solution to the equations of motion for the scalar components of the superfields involved. Two cases - that where a configuration belonging to the type of two parallel walls is saturated in the sense of Bogomol'nyi, Prasad, and Sommerfeld (BPS) and that where such a configuration is not BPS-saturated - are considered individually. For the first case, it is shown that, at low initial velocities, a collision of the walls is virtually an elastic reflection somewhat delayed in time. It is also demonstrated that, in this case, it is possible to introduce a collective variable that has the meaning of an internal parameter of the configuration and which can be treated as a dynamical (time-dependent) variable and to describe the dynamics of the system in terms of an effective Lagrangian. For the second case, it is found that, for collisions, there is a critical value of vcr ≅ 0.9120 for the initial velocity vi. For vi cr, the reflection of the walls occurs, the vacuum between the walls remaining unchanged. For vi > vcr, the collision process is accompanied by a change in the vacuum state between the walls
Near-BPS-saturated rotating electrically charged black holes as string states
We construct generating solutions for general D-dimensional (4≤D≤9) rotating, electrically charged, black holes in the effective action of toroidally compactified heterotic (or Type IIA) string. The generating solution is parameterized by the ADM mass, two electric charges and [(D-1)/2] angular momenta (as well as the asymptotic values of one toroidal modulus and the dilaton field). For D≥6, those are generating solutions for general black holes in toroidally compactified heterotic (or type IIA) string. Since in the BPS-limit (extreme limit) these solutions have singular horizons or naked singularities, we address the near extreme solutions with all the angular momenta small enough. In this limit, the thermodynamic entropy can be cast in a suggestive form, which has a qualitative interpretation as microscopic entropy of (near)-BPS-saturated charged string states of toroidally compactified heterotic string, whose target-space angular momenta are identified as [(D-1)/2] U(1) left-moving world-sheet currents. (orig.)
The stem cell walls of alfalfa [Medicago sativa (L.) ssp. sativa] genotype 252 have high cellulose and lignin concentrations, while stem cell walls of genotype 1283 have low cellulose and lignin concentrations. The GeneChip® Medicago Genome Array, developed for Medicago truncatula, is a suitable pla...
Huang, Chuan-Hsiang; Gabelli, Sandra B.; Oldfield, Eric; Amzel, L. Mario (UIUC); (JHU-MED)
2010-11-15
Bisphosphonates (BPs) are a class of compounds that have been used extensively in the treatment of osteoporosis and malignancy-related hypercalcemia. Some of these compounds act through inhibition of farnesyl diphosphate synthase (FPPS), a key enzyme in the synthesis of isoprenoids. Recently, nitrogen-containing bisphosphonates (N-BPs) used in bone resorption therapy have been shown to be active against Trypanosoma cruzi, the parasite that causes American trypanosomiasis (Chagas disease), suggesting that they may be used as anti-trypanosomal agents. The crystal structures of TcFPPS in complex with substrate (isopentenyl diphosphate, IPP) and five N-BP inhibitors show that the C-1 hydroxyl and the nitrogen-containing groups of the inhibitors alter the binding of IPP and the conformation of two TcFPPS residues, Tyr94 and Gln167. Isothermal titration calorimetry experiments suggest that binding of the first N-BPs to the homodimeric TcFPPS changes the binding properties of the second site. This mechanism of binding of N-BPs to TcFPPS is different to that reported for the binding of the same compounds to human FPPS.
BPS Explained II: Calculating the Equilibration Rate in the Extreme Quantum Limit
Singleton, Robert L
2007-01-01
This is the second in a series of two lectures on the technique of dimensional continuation, a new method for analytically calculating certain energy transport quantities in a weakly to moderately coupled plasma. Recently, this method was employed by Brown, Preston, and Singleton (BPS) to calculate the electron-ion temperature equilibration rate and the charged particle stopping power to leading and next-to-leading order in the plasma coupling. In this lecture, I develop the framework further, and then explicitly calculate the electron-ion temperature equilibration rate in the high temperature limit. This method captures all short and long distance physics to second order in the plasma coupling. This analytic perturbative technique is applicable for ignition in inertial confinement fusion and for other processes in hot a weakly coupled plasma.
BPS Zk strings, string tensions and confinement in non-Abelian theories
In this talk we review some generalizations of 't Hooft and Mandelstam ideas on confinement for theories with non-Abelian unbroken gauge groups. In order to do that, we consider N=2 super Yang-Mills with one flavor and a mass breaking term. One of the spontaneous symmetry breaking is accomplished by a scalar that can be in particular in the representation of the diquark condensate. We analyze the phases of the theory. In the superconducting phase, we show the existence of BPS Zk-strings and calculate exactly their string tension in a straightforward way. We also find that magnetic fluxes of the monopole and Zk-strings are proportional to one another allowing for monopole confinement in a phase transition. We further show that some of the resulting confining theories can be obtained by adding a deformation term N 2 or N = 4 superconformal theories. (author)
On super form factors of half-BPS operators in N=4 super Yang-Mills
We compute form factors of half-BPS operators in N=4 super Yang-Mills dual to massive Kaluza-Klein modes in supergravity. These are appropriate supersymmetrisations Tk of the scalar operators Tr (ϕk) for any k, which for k = 2 give the chiral part of the stress-tensor multiplet operator. Using harmonic superspace, we derive simple Ward identities for these form factors, which we then compute perturbatively at tree level and one loop. We propose a novel on-shell recursion relation which links form factors with different numbers of fields. Using this, we conjecture a general formula for the n-point MHV form factors of Tk for arbitrary k and n. Finally, we use supersymmetric generalised unitarity to derive compact expressions for all one-loop MHV form factors of Tk in terms of one-loop triangles and finite two-mass easy box functions
Algebraicity and Asymptotics: An explosion of BPS indices from algebraic generating series
Mainiero, Tom
2016-01-01
It is an observation of Kontsevich and Soibelman that generating series that produce certain (generalized) Donaldson Thomas invariants are secretly algebraic functions over the rationals. From a physical perspective this observation arises naturally for DT invariants that appear as BPS indices in theories of class S[A]: explicit algebraic equations (that completely determine these series) can be derived using (degenerate) spectral networks. In this paper, we conjecture an algebraic equation associated to DT invariants for the Kronecker 3-quiver with dimension vectors (3n,2n), n>0 in the non-trivial region of its stability parameter space. Using a functional equation due to Reineke, we show algebraicity of generating series for Euler characteristics of stable moduli for the Kronecker m-quiver assuming algebraicity of generating series for DT invariants. In the latter part of the paper we deduce very explicit results on the asymptotics of DT invariants/Euler characteristics under the assumption of algebraicity ...
Jamet, Elisabeth; Canut, Hervé; Boudart, Georges; Albenne, Cécile; Pont-Lezica, Rafael F
2008-01-01
This chapter covers our present knowledge of cell wall proteomics highlighting the distinctive features of cell walls and cell wall proteins in relation to problems encountered for protein extraction, separation and identification. It provides clues to design strategies for efficient cell wall proteomic studies. It gives an overview of the kinds of proteins that have yet been identified: the expected proteins vs the identified proteins. Finally, the new vision of the cell wall proteome, and t...
转基因大豆BPS-CV127-9 PCR定量检测研究%Quantitative Detection of Genetically Modified Soybean BPS-CV127-9
李宁; 赵蕾; 孙红炜; 李凡; 杨淑珂; 路兴波
2012-01-01
A quantitative method to detect the transgenic soybean BPS-CV-127-9 by using real-time PCR technique based on fluorescence dye SYBR Green I was investigated in this study. The endogenous lectin gene and the 5' flanking sequences of BPS-CV-127-9 were amplified through the specific primers,and the transgenic content was then calculated according to the standard curve equation. Meanwhile the specificity of PCR amplification was analyzed by corresponding melting curves. The results showed that the standard curves of lectin and the 5' flanking sequences of BPS-CV-127-9 genes have good linear relationship, and their R values were 0. 999 and 0. 998, respectively. The coefficient of variance was 1. 50%-18. 51% and standard deviation was 0.02-0.07. Four mixed samples with genetically modified contents of BPS-CV-127-9 was 0.05% ,0.1% ,0.5% and 1% respectively were detected,and the detection results agreed well with actual value. In conclusion,this method was fast, sensitive, simple, accurate, specific and of high throughput, and could be used to detect transgenic soybean BPS-CV-127-9 quantificationally.%采用SYBR Green实时荧光定量PCR技术,建立转基因大豆BPS-CV127-9的定量检测方法.通过设计特异引物,扩增内标准基因lectin和BPS-CV127-9的5’侧翼序列,建立2种基因的拷贝数-CT标准曲线,根据标准曲线方程计算样品中的转基因含量,并且通过熔解曲线分析扩增反应特异性.结果表明,lectin基因和侧翼序列标准曲线线性关系良好,R2值分别为0.999和0.998,变异系数(CV) 1.50％～18.51％、标准偏差(SD)0.02 ～0.07.检测4个已知BPS-CV127-9含量(1％、0.5％、0.1％、0.05％)的转基因混合样品,实测值与实际值接近.该检测方法具有快速、灵敏、准确、特异、高通量等优点,可以作为转基因大豆BPS-CV127-9的定量检测方法.
More on BPS States in N = 4 $$ \\mathcal{N}=4 $$ Supersymmetric Yang-Mills Theory on R × S 3
Yokoyama, Shuichi
2014-01-01
We perform a systematic analysis on supersymmetric states in N = 4 $$ \\mathcal{N}=4 $$ supersymmetric Yang-Mills theory (SYM) on R × S 3 . We find a new set of 1/16 BPS equations and determine the precise configuration of the supersymmetric states by solving all 1/16 BPS equations when they are valued in Cartan subalgebra of a gauge group and the fermionic fields vanish. We also determine the number of supersymmetries preserved by the supersymmetric states varying the parameters of the BPS so...
The quantum 1/2 BPS Wilson loop in ${\\cal N}=4$ Chern-Simons-matter theories
Bianchi, Marco S; Leoni, Matias; Mauri, Andrea; Penati, Silvia; Seminara, Domenico
2016-01-01
In three dimensional ${\\cal N}=4$ Chern-Simons-matter theories two independent fermionic Wilson loop operators can be defined, which preserve half of the supersymmetry charges and are cohomologically equivalent at classical level. We compute their three-loop expectation value in a convenient color sector and prove that the degeneracy is uplifted by quantum corrections. We expand the matrix model prediction in the same regime and by comparison we conclude that the quantum 1/2 BPS Wilson loop is the average of the two operators. We provide an all-loop argument to support this claim at any order. As a by-product, we identify the localization result at three loops as a correction to the framing factor induced by matter interactions. Finally, we comment on the quantum properties of the non-1/2 BPS Wilson loop operator defined as the difference of the two fermionic ones.
Perturbative evaluation of circular 1/2 BPS Wilson loops in N = 6 Super Chern-Simons theories
Griguolo, Luca; Poggi, Matteo; Seminara, Domenico
2013-01-01
We present a complete two-loop analysis of the quantum expectation value for circular BPS Wilson loops in ABJ(M) theories. We examine in details the 1/2 BPS case, that requires non-trivial fermionic couplings with the contour, finding perfect agreement with the exact matrix model answer at zero framing. The result is obtained through a careful application of DRED regularization scheme, combined with a judicious rearrangement of the relevant perturbative contributions that reduces the computation to simple integrals. We carefully analyze the contribution of fermions that is crucial for the consistency with the localization procedure and point out the arising of pivotal evanescent terms, discussing their meaning in relation to Ward identities.
Microscopic entropy of the most general BPS black hole for type II/M-theory on torii
In the present dissertation we review the statistical computation of the entropy for the most general static BPS black hole solution in the framework of toroidally compactified type II/M-theory. This achievement is inscribed within a research project aimed to the study of the microscopic properties of this kind of solutions in relation to U-duality invariants (e.g. the entropy) computed on the corresponding macroscopic (supergravity) description. (orig.)
N=2 SUGRA BPS Multi-center solutions, quadratic prepotentials and Freudenthal transformations
Fernandez-Melgarejo, J J
2013-01-01
We present a detailed description of N=2 stationary BPS multicenter black hole solutions for quadratic prepotentials with an arbitrary number of centers and scalar fields making a systematic use of the algebraic properties of the matrix of second derivatives of the prepotential, $\\mathcal{S}$, which in this case is a scalar-independent matrix. In particular we obtain bounds on the physical parameter of the multicenter solution such as horizon areas and ADM mass. We discuss the possibility and convenience of setting up a basis of the symplectic vector space built from charge eigenvectors of the $\\ssigma$, the set of vectors $(\\Ppm q_a)$ with $\\Ppm$ $\\ssigma$-eigenspace proyectors. The anti-involution matrix $\\mathcal{S}$ can be understood as a Freudenthal duality $\\tilde{x}=\\ssigma x$. We show that this duality can be generalized to "Freudenthal transformations" $$x\\to \\lambda\\exp(\\theta \\ssigma) x= a x+b\\tilde{x}$$ under which the horizon area, ADM mass and intercenter distances scale up leaving constant the ...
N=2 SUGRA BPS multi-center black holes and freudenthal triple systems
Torrente-Lujan E.
2015-01-01
Full Text Available We present a detailed description of N = 2 stationary BPS multicenter black hole solutions for quadratic prepotentials with an arbitrary number of centers and scalar fields making a systematic use of the algebraic properties of the matrix of second derivatives of the prepotential, S, which in this case is a scalar-independent matrix. The anti-involution matrix S can be understood as a Freudenthal duality x̃ = Sx. We show that this duality can be generalized to “Freudenthal transformations” x→λexp(θSx=ax+bx˜$x \\to \\lambda \\exp \\left( {\\theta S} \\rightx = ax + b\\tilde x$ under which the horizon area, ADM mass and intercenter distances scale up leaving constant the scalars at the fixed points. In the special case λ = 1, “S-rotations”, the transformations leave invariant the solution. The standard Freudenthal duality can be written as x˜=exp (π2S x$\\tilde x = {\\rm{exp }}\\left( {{\\pi \\over 2}S} \\right{\\rm{ }}x$. We argue that these generalized transformations leave invariant not only the quadratic preotential theories but also the general stringy extremal quartic form Δ4, Δ4(x = Δ4(cos θx + sin θx̃ and therefore its entropy at lowest order.
Topological charged BPS vortices in Lorentz-violating Maxwell-Higgs electrodynamics
Casana, R
2014-01-01
We have performed a complete study of BPS vortex solutions in the Abelian sector of the standard model extension (SME). Specifically we have coupled the SME electromagnetism with a Higgs field which is supplemented with a Lorentz-violating CPT-even term. We have verified that Lorentz-violation (LV) belonging to Higgs sector allows to interpolate between some well known models like, Maxwell-Higgs, Chern-Simons-Higgs and Maxwell-Chern-Simons-Higgs. We can also observed that the electrical charged density distribution is nonnull in both CPT-even and CPT-odd models, however the total electric charge in the CPT-even case is null whereas in the CPT-odd one it is proportional to the quantized magnetic flux. The following general results can be established in relation to the LV introduced in the Higgs sector: it changes the vortex \\emph{Ansatz} and the gauge field boundary conditions. The last one is responsible for the magnetic flux besides being proportional to the winding number also depends explicitly in the Lore...
Half BPS states in AdS_5 x Y^{p,q}
Gava, Edi; Milanesi, Giuseppe; O'Loughlin, Martin
2008-01-01
We study a class of solutions of IIB Supergravity which are asymptotically AdS_5 x Y^{p,q}. They have an R x SO(4) x SU(2) x U(1) isometry and preserve half of the 8 supercharges of the background geometry. They are described by a set of second order differential equations that we have found and analysed in a previous paper, where we studied 1/8 BPS states in the maximally supersymmetric AdS_5 x S^5 background. These geometries correspond to certain chiral primary operators of the N=1 superconformal quiver theories, dual to IIB theory on AdS_5 x Y^{p,q}. We also show how to recover the AdS_5 x Y^{p,q} backgrounds by suitably doubling the number of preserved supersymmetries. We then solve the differential equations perturbatively in a large AdS_5 radius expansion, imposing asymptotic AdS_5 x Y^{p,q} boundary conditions. We compute the global baryonic and mesonic charges, including the R-charge. As for the computation of the mass, i.e. the conformal dimension D of the dual field theory operators, which is notor...
Half BPS states in AdS5 x Yp,q
We study a class of solutions of IIB supergravity which are asymptotically AdS5 x Yp,q. They have an R x SO(4) x SU(2) x U(1) isometry and preserve half of the 8 supercharges of the background geometry. They are described by a set of second order differential equations that we have found and analysed in a previous paper, where we studied 1/8 BPS states in the maximally supersymmetric AdS5 x S5 background. These geometries correspond to certain chiral primary operators of the N = 1 superconformal quiver theories, dual to IIB theory on AdS5 x Yp,q. We also show how to recover the AdS5 x Yp,q backgrounds by suitably doubling the number of preserved supersymmetries. We then solve the differential equations perturbatively in a large AdS5 radius expansion, imposing asymptotic AdS5 x Yp,q boundary conditions. We compute the global baryonic and mesonic charges, including the R-charge. As for the computation of the mass, i.e. the conformal dimension Δ of the dual field theory operators, which is notoriously subtle in asymptotically AdS backgrounds, we adopt the general formalism due to Wald and collaborators, which gives a finite result, and verify the relation Δ = 3R/2, demanded by the N = 1 superconformal algebra
Dimensional reduction of BPS attractors in AdS gauged supergravities
Hristov, Kiril
2014-01-01
We relate across dimensions BPS attractors of black strings and black holes of various topology in gauged supergravities with nontrivial scalar potential. The attractors are of the form AdS$_{2, 3} \\times \\Sigma^{2, 3}$ in 4, 5, and 6 dimensions, and can be generalized to some higher dimensional analogs. Even though the attractor geometries admit standard Kaluza-Klein and Scherk-Schwarz reductions, their asymptotic AdS spaces in general do not. The resulting lower dimensional objects are black holes with runaway asymptotics in supergravity theories with no maximally symmetric vacua. Such classes of solutions are already known to exist in literature, and results here suggest an interpretation in terms of their higher-dimensional origin that often has a full string theory embedding. In a particular relevant example, the relation between 5d Benini-Bobev black strings arXiv:1302.4451 and a class of 4d Cacciatori-Klemm black holes arXiv:0911.4926 is worked out in full detail, providing a type IIB and dual field th...
1/16-BPS Black Holes and Giant Gravitons in the AdS_5 X S^5 Space
Kim, S; Kim, Seok; Lee, Ki-Myeong
2006-01-01
We explore 1/16-BPS objects of type IIB string theory in AdS_5 * S^5. First, we consider supersymmetric AdS_5 black holes, which should be 1/16-BPS and have a characteristic that not all physical charges are independent. We point out that the Bekenstein-Hawking entropy of these black holes admits a remarkably simple expression in terms of (dependent) physical charges, which suggests its microscopic origin via certain Cardy or Hardy-Ramanujan formula. We also note that there is an upper bound for the angular momenta given by the electric charges. Second, we construct a class of 1/16-BPS giant graviton solutions in AdS_5 * S^5 and explore their properties. The solutions are given by the intersections of AdS_5 * S^5 and complex 3 dimensional holomorphic hyperspaces in C^{1+5}, the latter being the zero loci of three holomorphic functions which are homogeneous with suitable weights on coordinates. We investigate examples of giant gravitons, including their degenerations to tensionless strings.
Strandén, A M; Ehlert, K; Labischinski, H.; Berger-Bächi, B.
1997-01-01
The femAB operon is involved in the formation of the characteristic pentaglycine side chain of the staphylococcal peptidoglycan. Allele replacement of the femAB operon with the tetracycline resistance determinant tetK in a methicillin-resistant Staphylococcus aureus strain resulted in impaired growth, methicillin hypersusceptibility, and lysostaphin resistance. The usual pentaglycine cross-bridges were replaced by monoglycine bridges exclusively, and cross-linking of the peptidoglycan strands...
2015-10-01
It is no news to anyone that health transcends national borders, driven by cross-border movement of vectors, populations, health professionals, climate, even policy trends. There is an increasing recognition that it is, in fact, a small world: we are affected by and affect what happens to our neighbors, whether they live around the corner or on the other side of the globe. This conception underpins the shift from the term international health to global health in policy discussions. The new terminology reflects change across several dimensions: from an approach in which there is one medicine for the developed world and another for developing countries, to an appreciation that we all have a stake in one another's wellbeing; from a primarily biomedical focus on treatment to a more multidisciplinary, population health focus taking into consideration a range of interventions to improve health and well-being, including the social and environmental determinants of health; and from a vertical bilateral-aid approach focused on specific diseases, to systems and ecological approaches addressing the complexities of health, involving multiple partnerships. PMID:26947274
Domain Walls in Extended Lovelock Gravity
dS, U Camara; Lima, A L Alves; Sotkov, G M
2012-01-01
We derive a BPS-like first order system of equations for a family of flat static domain walls (DWs) of dimensionally extended cubic Lovelock Gravity coupled to massive scalar self-interacting matter. The explicit construction of such DWs is achieved by introducing of an appropriate matter superpotential. We further analyse the dependence of the geometric properties of the asymptotically AdSd space-times representing distinct DWs on the shape of the matter potential, on the values of the Lovelock couplings and on the scalar field boundary conditions. Few explicit examples of Lovelock DWs interpolating between AdS-type vacua of different cosmological constants are presented. In five dimensions our method provides interesting solutions of the Myers-Robinson Quasi-topological Gravity in the presence of matter important for the description of the specific renormalization group flows in its holographic dual four-dimensional CFT perturbed by relevant operators.
Escherichia coli Protein Expression System for Acetylcholine Binding Proteins (AChBPs.
Nikita Abraham
Full Text Available Nicotinic acetylcholine receptors (nAChR are ligand gated ion channels, identified as therapeutic targets for a range of human diseases. Drug design for nAChR related disorders is increasingly using structure-based approaches. Many of these structural insights for therapeutic lead development have been obtained from co-crystal structures of nAChR agonists and antagonists with the acetylcholine binding protein (AChBP. AChBP is a water soluble, structural and functional homolog of the extracellular, ligand-binding domain of nAChRs. Currently, AChBPs are recombinantly expressed in eukaryotic expression systems for structural and biophysical studies. Here, we report the establishment of an Escherichia coli (E. coli expression system that significantly reduces the cost and time of production compared to the existing expression systems. E. coli can efficiently express unglycosylated AChBP for crystallography and makes the expression of isotopically labelled forms feasible for NMR. We used a pHUE vector containing an N-terminal His-tagged ubiquitin fusion protein to facilitate AChBP expression in the soluble fractions, and thus avoid the need to recover protein from inclusion bodies. The purified protein yield obtained from the E. coli expression system is comparable to that obtained from existing AChBP expression systems. E. coli expressed AChBP bound nAChR agonists and antagonists with affinities matching those previously reported. Thus, the E. coli expression system significantly simplifies the expression and purification of functional AChBP for structural and biophysical studies.
Mody, Astrid
2012-01-01
The introduction of Light Emitting Diodes (LEDs) in the built environment has encouraged myriad applications, often embedded in surfaces as an integrated part of the architecture. Thus the wall as responsive luminous skin is becoming, if not common, at least familiar. Taking into account how wall...
We derive equations of motion for the tachyon field living on an unstable non-BPS D-brane in the level truncated open cubic superstring field theory in the first non-trivial approximation. We construct a special time dependent solution to this equation which describes a rolling tachyon. It starts from the perturbative vacuum and approaches one of stable vacua in infinite time. We investigate conserved energy functional and show that its different parts dominate in different stages of the evolution. We show that the pressure for this solution has its minimum at zero time and goes to minus energy at infinite time. (author)
Monitoring and control system of B-PS and S-PS fault interlock in the storage ring of SSRF
In this paper, we report the local monitor and control system of fault interlock based on software design of S7-200 and S7-300 according to characteristics of the B-PS and S-PS in storage ring of SSRF. The remote monitor and control system based on EPICS are presented. The system architecture and key technologies in hardware and software designs are expatiated. Advantages of the system include the friendly interface and simple operation. The system has been working stably. (authors)
All three-loop four-point correlators of half-BPS operators in planar N=4 SYM
Chicherin, Dmitry; Heslop, Paul; Sokatchev, Emery
2015-01-01
We obtain the planar correlation function of four half-BPS operators of arbitrary weights, up to three loops. Our method exploits only elementary properties of the integrand of the planar correlator, such as its symmetries and singularity structure. This allows us to write down a general ansatz for the integrand. The coefficients in the ansatz are fixed by means of a powerful light-cone OPE relation between correlators with different weights. Our result is formulated in terms of a limited number of functions built from known one-, two- and three-loop conformal integrals. These results are useful for checking recent integrability predictions for the OPE structure constants.
Interactions of Domain Walls of SUSY Yang-Mills as D-Branes
Armoni, A; Armoni, Adi; Hollowood, Timothy J.
2006-01-01
Domain walls in supersymmetric Yang-Mills are BPS configurations which preserve two supercharges of the parent theory and so their tensions are known exactly. On the other hand, they have been described as D-branes for the confining string. This leads to a description of their collective dynamics in terms of a 2+1 -dimensional gauge theory with two supersymmetries and a Chern-Simons term. We show that this open string description can capture the qualitative behaviour of the forces between the domain walls for an arbitrary configuration of n walls at leading order in 1/N, extending earlier calculations for two walls. The potential admits a supersymmetric bound state when the n walls are all coincident and asymptotes to a constant at large separation with an n dependence which agrees perfectly with the exact tension formula.
Interactions of domain walls of SUSY Yang-Mills as D-branes
Domain walls in supersymmetric Yang-Mills are BPS configurations which preserve two supercharges of the parent theory and so their tensions are known exactly. On the other hand, they have been described as D-branes for the confining string. This leads to a description of their collective dynamics in terms of a 2+1-dimensional gauge theory with two supersymmetries and a Chern-Simons term. We show that this open string description can capture the qualitative behaviour of the forces between the domain walls for an arbitrary configuration of n walls at leading order in 1/N, extending earlier calculations for two walls. The potential admits a supersymmetric bound state when the n walls are all coincident and asymptotes to a constant at large separation with an n dependence which agrees perfectly with the exact tension formula
The purpose of this work was to prepare nanocomposites by mixing multi-walled carbon nanotubes (MWCNT) with nitrile and hydrogenated nitrile elastomers (NBR and HNBR). Utilization of transmission electronic microscopy (TEM), scanning electron microscopy (SEM), and small- and wide-angle X-ray scattering techniques (SAXS and WAXS) for advanced morphology observation of conducting filler-reinforced nitrile and hydrogenated nitrile rubber composites is reported. Principal results were increases in hardness (maximally 97 Shore, type A), elastic modulus (maximally 981 MPa), tensile strength (maximally 27.7 MPa), elongation at break (maximally 216%), cross-link density (maximally 7.94 x 1028 m-3), density (maximally 1.16 g cm-3), and tear strength (11.2 kN m-1), which were clearly visible at particular acrylonitrile contents both for unhydrogenated and hydrogenated polymers due to enhanced distribution of carbon nanotubes (CNT) and their aggregated particles in the applied rubber matrix. Conclusion was that multi-walled carbon nanotubes improved the performance of nitrile and hydrogenated nitrile rubber nanocomposites prepared by melt compounding.
Highlights: ► We measured the instantaneous flow velocity using 2D-Particle Image Velocimetry. ► Recirculation bubbles, vortices, detachment and reattachment zones are showed. ► The influence of the ReH and Rej/ReH was studied. ► The Rej/ReH determines the effects produced around the component. - Abstract: The air flow around a cubic obstacle mounted on one wall of a rectangular channel was studied experimentally. The obstacle represents an electronic component and the channel the space between two parallel printed circuit boards (PCBs). The flow was produced by the combination of a channel stream and a jet which issued from a circular nozzle placed at the wall opposite from where the component is mounted. With this aim, a test rig was designed and built to carry out experiments with both the above mentioned configurations and other cooling arrangements. Planar Particle Image Velocimetry (PIV) was employed to measure the instantaneous flow velocity on several planes covering the space around the component. The mean velocity and the Reynolds stresses were obtained from averaging the instantaneous velocity, and the mean flow showed a complex pattern with different features such as recirculation bubbles, vortices, detachment and reattachment zones. The influence of two parameters, namely the channel Reynolds number and the jet-to-channel Reynolds number ratio, on these flow features was studied considering nine cases that combined three values of the channel Reynolds number (3410, 5752 and 8880) and three values of the ratio (0.5, 1.0 and 1.5). The results show that the Reynolds number ratio determines the drag produced on the jet and the deflection from its geometric axis due to the channel stream. In all the cases corresponding to the lowest value of the ratio, the jet was dragged and did not impact the component. This fact accounts for the non-existence of the Upper Horseshoe Vortex and changes in the flow characteristics at the region over the component.
Domain Walls and Flux Tubes in N=2 SQCD D-Brane Prototypes
Shifman, M
2003-01-01
This paper could have been entitled "D branes and strings from flesh and blood." We study field theoretic prototypes of D branes/strings. To this end we consider (2+1)-dimensional domain walls in (3+1)-dimensional N=2 SQCD with SU(2) gauge group and two quark flavors in the fundamental representation. This theory is perturbed by a small mass term of the adjoint matter which, in the leading order in the mass parameter, does not break N=2 supersymmetry, and reduces to a (generalized) Fayet-Iliopoulos term in the effective low-energy N=2 SQED. We find 1/2 BPS-saturated domain wall solution interpolating between two quark vacua at weak coupling, and show that this domain wall localizes a U(1) gauge field. To make contact with the brane/string picture we consider the Abrikosov-Nielsen-Olesen magnetic flux tube in one of two quark vacua and demonstrate that it can end on the domain wall. We find an explicit 1/4 BPS-saturated solution for the wall/flux tube junction. We verify that the end point of the flux tube on ...
Lantsman, L
2006-01-01
We show that manifest superfluid properties of the Minkowskian Higgs model with vacuum BPS monopoles quantized by Dirac may be described in the framework of the Cauchy problem to the Gribov ambiguity equation. The latter equation specifies the ambiguity in choosing the covariant Coulomb (transverse) gauge for Yang-Mills fields represented as topological Dirac variables, may be treated as solutions to the Gauss law constraint at the removal of temporal components of these fields. We demonstrate that the above Cauchy problem comes just to fixing the covariant Coulomb gauge for topological Dirac variables in the given initial time instant $t_0$ and finding the solutions to the Gribov ambiguity equation in the shape of vacuum BPS monopoles and excitations over the BPS monopole vacuum referring to the class of multipoles. The next goal of the present study will be specifying the look of Gribov topological multipliers entering Dirac variables in the Minkowskian Higgs model quantized by Dirac, especially at the spat...
Precision calculation of 1/4-BPS Wilson loops in AdS$_5\\times S^5$
Forini, V; Griguolo, L; Seminara, D; Vescovi, E
2015-01-01
We study the strong coupling behaviour of $1/4$-BPS circular Wilson loops (a family of "latitudes") in ${\\cal N}=4$ Super Yang-Mills theory, computing the one-loop corrections to the relevant classical string solutions in AdS$_5\\times$S$^5$. Supersymmetric localization provides an exact result that, in the large 't Hooft coupling limit, should be reproduced by the sigma-model approach. To avoid ambiguities due to the absolute normalization of the string partition function, we compare the $ratio$ between the generic latitude and the maximal 1/2-BPS circle: Any measure-related ambiguity should simply cancel in this way. We use Gel'fand-Yaglom method to calculate the relevant functional determinants, that present some complications with respect to the standard circular case. After a careful numerical evaluation of our final expression we still find disagreement with the localization answer: The difference is encoded into a precise "remainder function". We comment on the possible origin and resolution of this dis...
Precision calculation of 1/4-BPS Wilson loops in AdS5×S5
Forini, V.; Puletti, V. Giangreco M.; Griguolo, L.; Seminara, D.; Vescovi, E.
2016-02-01
We study the strong coupling behaviour of 1/4-BPS circular Wilson loops (a family of "latitudes") in {N}=4 Super Yang-Mills theory, computing the one-loop corrections to the relevant classical string solutions in AdS5 ×S5. Supersymmetric localization provides an exact result that, in the large 't Hooft coupling limit, should be reproduced by the sigma-model approach. To avoid ambiguities due to the absolute normalization of the string partition function, we compare the ratio between the generic latitude and the maximal 1/2-BPS circle: any measure-related ambiguity should simply cancel in this way. We use the Gel'fand-Yaglom method with Dirichlet boundary conditions to calculate the relevant functional determinants, that present some complications with respect to the standard circular case. After a careful numerical evaluation of our final expression we still find disagreement with the localization answer: the difference is encoded into a precise "remainder function". We comment on the possible origin and resolution of this discordance.
Alonso-Izquierdo, Alberto
2016-01-01
In this paper zero modes of fluctuation are dissected around the two species of BPS vortices existing in the critical Higgs phase, where the scalar and vector meson masses are equal, of a gauged $\\mathbb{U}(1)$ nonlinear $\\mathbb{CP}^1$-model. If $2\\pi n$, $n\\in \\mathbb{Z}$, is the quantized magnetic flux of the two species of BPS vortex solutions, $2n$ linearly independent vortex zero modes for each species are found and described. The existence of two species of moduli spaces of dimension $2n$ of these stringy topological defects is thus locally shown.
Bisphenol A (BPA) is gradually being phased out of many consumer products and processes leading to potential increases in human and environmental exposures to relatively understudied replacement compounds, including Bisphenol S (BPS). Research from our lab has shown that BPA and...
Lee, Gil-yong; Jung, Min-kyung; Ryoo, Sung-nam; Ha, Sam-chul [Digital Appliance R and D, LG Electronics, Seoul 153-801 (Korea, Republic of); Park, Myung-seok [LG Solar Energy, Seoul 150-721 (Korea, Republic of); Kim, Sunhoe [Department of New Energy and Resource Engineering, Sangji University, Wonju, Gangwon 220-702 (Korea, Republic of)
2010-12-15
In order to satisfy the demands of customers, cost innovation of fuel cell systems is required for the commercialization of the fuel cell. Since the stack is one of the most expensive parts in a fuel cell system, cost reduction of stack is required for fuel cell commercialization. For this effort stainless steel 304 sheets were etched for the flow field and then coated for corrosion resistance. This enables the development of highly cost-effective bipolar plates (BPs) for a Proton Exchange Membrane Fuel Cell (PEMFC) stack of a 1 kW-class for Residential Power Generator (RPG). LG Electronics (LGE) developed a metal stack of 64 cells with the developed BPs and achieved a performance rating of 0.75 V/cell at 200 mA/cm{sup 2}. LGE also achieved a stack volume reduction of 20% compared to a stack of the same specifications consisting of graphite material BPs. The volume decrease can be represented as a cost reduction. LGE achieved the very low cost innovation to 1 USD per cell with cells developed from etched metal BPs. LGE also achieved 500 h of operation with LGE's RPG system; this test is still ongoing. The degradation rate of the stack was 27 {mu}V/hr. The end of life of the stack was estimated at approximately 17,000 h. (author)