Results for "Renata Jora"

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Note on the Witten index and the dynamical breaking of a supersymmetric gauge theoryFeb 28 2019We estimate the Witten index for a supersymmetric gauge theory with or without massless matter. For pure supersymmetric Yang Mills our result reproduces the results in the literature. For the known theories with dynamical symmetry breaking the Witten ... More
Note on the Witten index and the dynamical breaking of a supersymmetric gauge theory IIFeb 28 2019Mar 04 2019We estimate the Witten index for a supersymmetric gauge theory with or without massless matter. For pure supersymmetric Yang Mills our result reproduces the results in the literature. For the known theories with dynamical symmetry breaking the Witten ... More
About the electroweak vacuum and its connection with the quark condensatesNov 11 2016We make a change of variable in the standard model Higgs field by a fermion operator and show that the latter is responsible for the electroweak vacuum. By computing the vacuum expectation value of this fermion operator in the path integral formalism ... More
A nonperturbative method for the scalar field theoryMar 10 2014Jan 10 2015We compute an all order correction to the scalar mass in the \Phi^4 theory using a new method of functional integration adjusted also to the large couplings regime.
A theoretical estimate of the Higgs boson massAug 18 2012Using the invariance of the electroweak vacuum in the presence of a background Z field we estimate the mass of the Higgs boson in the standard model at m_H=125.9 GeV.
About flavor, spin and colorApr 21 2010Aug 19 2010Chiral symmetry breaking (restoration) for SU(N) gauge theories is a topic of great interest and not yet fully explained. We consider the phenomenon as a collective spin effect and determine its behavior in terms of the number of flavors, N_f.
Spontaneous symmetry breaking and Goldstone theorem for composite states revisitedJul 05 2016We discuss the well-known phenomenon of spontaneous symmetry breaking for a linear sigma model for scalar and pseudoscalar mesons based on the meson composite structure and the normalization of the quantum states. To test our formulation and validate ... More
Note about the implementation of finite symmetries in the lepton sectorMar 15 2013Dec 09 2013Assuming that the leptonic mixing matrix is given in first approximation by the tribimaximal form we deduce some consequences with regard to the finite symmetries that may be applied in the minimal lepton sector of the electroweak theory.
Note on a sigma model connection with instanton dynamicsJan 16 2008Feb 01 2008It is well known that the instanton approach to QCD generates an effective term which looks like a three flavor determinant of quark bilinears. This has the right behavior to explain the unusual mass and mixing of the $\eta(958)$ meson, as is often simply ... More
Generalized Sigma Model Description of the Light J=0 MesonsJan 26 2006Within a linear sigma model framework, possible mixing between two chiral nonets (a two quark nonet, and a four quark nonet) below 2 GeV is studied. Incorporating the U(1)$_A$ behavior of the underlying QCD, and working in the isospin invariant limit, ... More
The abelian Higgs model and its phase transitions revisitedFeb 15 2015The abelian Higgs model and its phase structure are discussed from the perspective that the gauge and scalar fields admit a dual description in terms of fermion variables. The results which indicate the presence of three main phases: Coulomb, Higgs and ... More
Vacuum energy in some particular quantum field theoriesFeb 19 2016We study the properties of a class of quantum field theories endowed with an equal number of anti commuting and commuting field variables, the most common example being the supersymmetric models. Based on the scaling properties of the partition function ... More
Standard model effective potential from trace anomaliesJun 10 2017Jan 26 2018By analogy with the low energy QCD effective linear sigma model we construct a standard model effective potential based entirely on the requirement that the tree level and quantum level trace anomalies must be satisfied. We discuss a particular realization ... More
Dynamical electroweak breaking and contributions to supersymmetry breaking through logarithmic operatorsNov 22 2017We introduce in an arbitrary supersymmetric version of the standard model without elementary scalars a logarithmic operator which is irrelevant in the limit in which all symmetries are respected. However through a dynamical mechanism of the Nambu Jona ... More
About the mass corrections in an abelian Higgs modelMar 14 2016We study the corrections to the scalar boson mass in an abelian Higgs model by considering the global properties of the partition function. We find that although the two point function for the Higgs boson receives quantum corrections, the mass of the ... More
Note about Yang Mills, QCD and their supersymmetric counterpartsJan 07 2011Apr 25 2011We analyze in an effective Lagrangian framework the connection between Super QCD (Super Yang Mills) and QCD (Yang Mills) by highlighting the crucial role that the zero modes play in the process of decoupling gluinos and squarks.
Quark and gluon condensates in QCD reevaluatedApr 08 2019We compute the quark and gluon condensates in $QCD$ with $N$ colors and $N_f$ flavors based on the renormalization group equations and on the knowledge of a single scale $\Lambda_{QCD}$. For $N=3$ and $N_f=3$ our findings are in the good range for $0.2\leq\Lambda_{QCD}\leq ... More
Witten index and dynamical supersymmetry breaking of a gauge theoryFeb 28 2019Mar 17 2019We estimate the Witten index for a supersymmetric gauge theory with or without massless matter. For pure supersymmetric Yang Mills our result reproduces the results in the literature. For the known theories with dynamical symmetry breaking the Witten ... More
Confinement and chiral phase transitions in QCD and superQCDSep 06 2018We study confinement and chiral symmetry breaking phase transitions for QCD and supersymmetric QCD. The method is based on some justified assumption regarding the behavior of the Green function relevant for the potential between two charges or a gap equation. ... More
Comment on some particular phases of supersymmetric QCDNov 01 2018We study two phases of supersymmetric QCD associated to the singularities of the renormalization constant of the fermion mass operator. We find a behavior of the potential between two charges for the phases of interest that it is consistent with Seiberg ... More
CP violating phases and a solution to the strong CP problemFeb 08 2018Feb 22 2018We present a solution to the strong CP problem based on the identification of the theta angle with twice the CP violating phase present in the CKM quark matrix. This solution washes out all the unwanted issues stemming form the strong CP phase and is ... More
Higgs boson mass from gauge invariant operatorsJul 07 2016Oct 31 2016We make the assumption that the vacuum correlators of the gauge invariant kinetic term of the Higgs doublet are the same before and after the spontaneous symmetry breaking of the theory. Based on this we determine the mass of the standard model Higgs ... More
Phase transitions for SU(N) gauge theories with arbitrary number of flavorsMay 27 2015Nov 28 2015We study the phase diagram of an $SU(N)$ gauge theory in terms of the number of colors $N$ and flavors $N_f$ with emphasis on the confinement and chiral symmetry breaking phases. We argue that as opposed to SUSY QCD there is a small region in the $(N,N_f)$ ... More
Higgs boson otherwiseMay 03 2009We propose an electroweak model based on the identification of the Higgs with the dilaton. We show that it is possible in this context to have a massless Higgs boson at tree and one loop levels without contradicting the main experimental and theoretical ... More
Note on the Witten index and the dynamical breaking of a supersymmetric gauge theoryJan 06 2019It is known that in order for a supersymmetric gauge theory to be dynamically broken a necessary but not sufficient condition is that the Witten index $(-1)^F=n_b^0-n_f^0$ is zero. In the case the Witten index is zero it is in general hard to distinguish ... More
An approach to QCD perturbative and non-perturbative beta functionsApr 06 2017Dec 11 2017Using the global properties of the QCD partition function we determine an all order perturbative beta function in the background gauge field method to find out that it has a simple expressions whose properties and consequences align with other recent ... More
Note on the Witten index and the dynamical breaking of a supersymmetric gauge theoryJan 06 2019Mar 17 2019It is known that in order for a supersymmetric gauge theory to be dynamically broken a necessary but not sufficient condition is that the Witten index $(-1)^F=n_b^0-n_f^0$ is zero. In the case the Witten index is zero it is in general hard to distinguish ... More
About electrodynamics, standard model and the quantization of the electrical chargeMay 24 2018Dec 04 2018The quantization of the electrical charge in the electrodynamics and of the hypercharge in the standard model are imposed in the theory based not on theoretical arguments but on the experimental observations. In this paper we propose a quantum consistency ... More
About the particle structure and content of the standard modelOct 28 2015We determine the number and distribution of the fermion states in the standard model based on the possible fermion representations of the gauge bosons. By extracting the even parity scalars from the fermion states we suggest the existence of multiple ... More
Vacuum energy in some particular quantum field theoriesFeb 19 2016Jun 09 2017We study the properties of a class of quantum field theories endowed with an equal number of anti commuting and commuting field variables, the most common example being the supersymmetric models. Based on the scaling properties of the partition function ... More
Exotic MSSMJan 11 2013We present an exotic version of the MSSM with the same particle content but with some of the states with negative kinetic energies. We discuss how the model can work quantum mechanically and also resolve some of the pressing issues of the regular MSSM. ... More
Do we need Feynman diagrams for higher orders perturbation theory?Feb 07 2012Jun 05 2012We compute the two and three loop corrections to the beta function for Yang-Mills theories in the background gauge field method and using the background gauge field as the only source. The calculations are based on the separation of the one loop effective ... More
A hierarchy of the quark masses in a top condensate model with multiple HiggsesOct 07 2013Mar 06 2014We discuss the quark masses in a top condensate model where not only two quark but also four quark composite states may exist. We show that the presence of the top color group SU(3)_1\times SU(3)_2 with the correct non anomalous quark representations ... More
CP violating phases and a solution to the strong CP problemFeb 08 2018We present a solution to the strong CP problem based on the identification of the theta angle with twice the CP violating phase present in the CKM quark matrix. This solution washes out all the unwanted issues stemming form the strong CP phase and is ... More
Note on the gluino condensate in supersymmetric Yang Mills theoryNov 01 2018We calculate gluino condensate for supersymmetric Yang Mills theory on general grounds without making any assumption with regard to the weak or strong regime of the theory. Our result coincides with that obtained from an instanton superpotential when ... More
Baryon asymmetry in the standard model revisitedJun 02 2018Sep 09 2018We compute the baryon asymmetry in the Universe in the framework of the standard model with the only source of CP violation in the CKM matrix. Our result is within and very close to the theoretical limits for baryon asymmetry found in the literature and ... More
Supersymmetric QCD with $N_f<N$ revisitedFeb 28 2019We introduce in supersymmetric QCD with $N_f<N$ additional meson singlet degrees of freedom made of $2N_f-2$ supermultiplets. We construct an alternative superpotential with $N_f^2$ constraints and show its consistency. Based on this superpotential we ... More
$Φ^4$ theory is trivialMar 25 2015We prove that the $\Phi^4$ theory is trivial for any values of the bare coupling constant $\lambda$ thus extending previous results referring to very strong couplings to the full range of values for this parameter. The method is based on all order properties ... More
Abelian Higgs model and its phase transitions revisitedFeb 15 2015Jun 09 2017The abelian Higgs model and its phase structure are discussed from the perspective that the gauge and scalar fields admit a dual description in terms of fermion variables. The results which indicate the presence of three main phases: Coulomb, Higgs and ... More
A nonperturbative method for the Yang Mills LagrangianNov 02 2014May 05 2015Using the properties of the partition function for a Yang Mills theory we compute simple relations among the renormalization constants. In the particular case of the background gauge field method we obtain that the all orders beta function for the gauge ... More
A nonperturbative method for QCDJun 22 2015Based on specific properties of the partition function and of the quantum correlators we derive the exact form of the beta function in the background gauge field method for QCD with an arbitrary number of flavors. The all order beta function we obtain ... More
A solution for the doublet-triplet splitting in $SU(5)$May 11 2019We present a solution to the doublet-triplet splitting problem in supersymmetric $SU(5)$ by enlarging the group to $SU(5)\times SU(5)$ and by introducing two supermultiplets in the $(5,5)$ and $(\bar{5},\bar{5})$ representations of the extended group. ... More
A hint of a strong supersymmetric standard modelMar 15 2014We discuss the supersymmetric standard model from the perspective that the up and down Higgs supermultiplets are composite states. We show that a Higgs multiplet in which the scalar states are bound states of two squarks and the corresponding Higgsinos ... More
About the role of scalars in a gauge theoryOct 23 2013Dec 07 2013We consider a new effective symmetry that acts on a gauge invariant Lagrangian. We show that the standard model after spontaneous symmetry breakdown is invariant under this symmetry which identifies up to a scale factor the gauge parameter with the elementary ... More
A semi perturbative method for QEDJul 23 2014We compute the QED beta function using a new method of functional integration. It turns out that in this procedure the beta function contains only the first two orders coefficients and thus corresponds to a new renormalization scheme, long time supposed ... More
A solution to the naturalness problemMay 30 2015Jun 09 2017We present a solution to the naturalness problem of the electroweak scale based on a change of variable in the Fourier space of non supersymmetric nature that transforms a boson into a fermion and viceversa. This is exemplified for that part of the standard ... More
Electromagnetic axial anomaly in a generalized linear sigma modelJan 03 2017Apr 27 2017We construct the electromagnetic anomaly effective term for a generalized linear sigma model with two chiral nonets, one with a quark-antiquark structure, the other one with a four quark content. We compute in the leading order of this framework the decays ... More
Generalized fermion symmetry, its currents algebra and Ward-Takahashi identitiesMar 23 2017Jun 09 2017We introduce a new local symmetry into the fermion sector of a gauge invariant Lagrangian which may or may not contain a scalar or spontaneous symmetry breaking. The Standard Model in the unitary gauge and QCD are particular cases where this symmetry ... More
Generalized linear sigma model with two glueballsJul 28 2018Oct 25 2018We present a generalized linear sigma model that includes both scalar and pseudoscalar glueballs in addition to a quark-antiquark as well as a four-quark chiral nonet. Utilizing the axial and trace anomalies of QCD (at the effective mesonic level), we ... More
Examining a possible cascade effect in chiral symmetry breakingAug 29 2016Dec 12 2016We examine a toy model and a cascade effect for confinement and chiral symmetry breaking which consists in several phase transitions corresponding to the formation of bound states and chiral condensates with different number of fermions for a strong group. ... More
Examining a possible cascade effect in chiral symmetry breakingAug 29 2016We examine a toy model and a cascade effect for confinement and chiral symmetry breaking which consists in several phase transitions corresponding to the formation of bound states and chiral condensates with different number of fermions for a strong group. ... More
A solution to the naturalness problemMay 30 2015We present a solution to the naturalness problem of the electroweak scale based on a change of variable in the Fourier space of non supersymmetric nature that transforms a boson into a fermion and viceversa. This is exemplified for that part of the standard ... More
Note on the standard model as an effective theoryOct 28 2015We present a criterion of consistency derived from the analogy between the partition function of a quantum field theory and that of a statistical system. Based on this we examine a new class of higher dimension operators that might act in the standard ... More
A purely quark Lagrangian from QCDSep 20 2015We present a method for determining a purely quark Lagrangian by mocking up the QCD partition function for large gauge couplings $g$. The resulting effective theory displays all the symmetries of low energy QCD and can be potentially used to explore hadron ... More
Comment on scalar glueball massJul 28 2018We study the interaction of scalar glueball with quark-antiquark and four-quark spinless meson fields within the framework of a generalized linear sigma model in which the trace anomaly of QCD is exactly realized. To determine the pure scalar glueball ... More
Electromagnetic trace anomaly in a generalized linear sigma modelSep 05 2017Nov 22 2017We build the electromagnetic trace anomaly effective term for a generalized linear sigma model with two chiral nonets, one with a quark-antiquark structure, the other one with a four quark content. In the leading order of this framework, we study the ... More
Model for light scalars in QCDDec 15 2006Jun 12 2007We propose a systematic procedure to study a generalized linear sigma model which can give a physical picture of possible mixing between $q{\bar q}$ and $qq{\bar q}{\bar q}$ low lying spin zero states. In the limit of zero quark masses, we derive the ... More
Tree level relations in a composite electroweak theoryJul 24 2014Nov 02 2014We work out simple tree level relations in a top condensate model with dynamical electroweak symmetry breaking. We find that in this picture the mass of the composite Higgs boson at tree level is given by $m_H^2=\frac{m_t^2}{2}$ where $m_t$ is the mass ... More
How important is $iε$ in QFT?Feb 28 2015May 25 2015We discuss the role of $i\epsilon$ in quantum field theories and suggest that it can be identified with the dimensional regularization parameter $i\epsilon=4-d$ thus clarifying and simplifying issues related to the infrared divergences without altering ... More
Note about lepton masses and mixings in two AnsatzeDec 09 2013We consider two Ansatze for the neutrino masses and mixings in which the permutation symmetry is implemented in various orders. We discuss the possible see-saw mechanisms and the charged lepton masses for the two cases in the presence of a Higgs triplet ... More
An analytical treatment of the neutrino masses and mixingsApr 30 2013Dec 09 2013We obtain analytical formulas which connect the neutrino masses and the leptonic mixing matrix with the entries in the mass matrix for the approximation in which the charged lepton mixing matrix is the unit matrix. We also extract the CP violation phase ... More
Two chiral nonet model with massless quarksJul 05 2007We present a detailed study of a linear sigma model containing one chiral nonet transforming under U(1)$_A$ as a quark-antiquark composite and another chiral nonet transforming as a diquark-anti diquark composite (or, equivalently from a symmetry point ... More
An approach to permutation symmetry for the electroweak theoryMay 06 2006Sep 08 2006The form of the leptonic mixing matrix emerging from experiment has, in the last few years, generated a lot of interest in the so-called tribimaximal type. This form may be naturally associated with the possibility of a discrete permutation symmetry ($S_3$) ... More
Mass Ansatze for the standard model fermions from a composite perspectiveAug 26 2016Aug 29 2016We consider a composite model in which the standard model fermions are bound states of elementary spin $\frac{1}{2}$ particles, the preons, situated in the conjugate product representation of the color group. In this framework we propose and analyze two ... More
A semiclassical approach for the Higgs bosonSep 28 2014Starting from the equations of motion of the fields involved in a theory with spontaneous symmetry breaking and by making simple assumptions regarding their behavior we derive simple tree level relations between the mass of the Higgs boson in the theory ... More
Naturalness in a simple two Higgs doublet modelFeb 26 2013Apr 19 2013We study the implications of a criterion of naturalness for a simple two Higgs doublet model in the context of the discovery of a Higgs like particle with a mass at 125 GeV. This condition which measures the amount of fine tuning further limits the parameter ... More
Naturally perturbed S$_3$ neutrinosOct 25 2012Apr 07 2013We simplify and extend our previous model for the masses and mixing matrix of three Majorana neutrinos based on permutation symmetry $S_3$ and the perturbations which violate this symmetry. The perturbations are arranged such that we get the smaller solar ... More
Doubly perturbed $S_3$ neutrinos and the $s_{13}$ mixing parameterJun 16 2010We further study a predictive model for the masses and mixing matrix of three Majorana neutrinos. At zeroth order the model yielded degenerate neutrinos and a generalized ``tribimaximal" mixing matrix. At first order the mass splitting was incorporated ... More
Perturbed S3 neutrinosSep 24 2009Dec 16 2010We study the effects of the perturbation which violates the permutation symmetry of three Majorana neutrinos but preserves the well known (23) interchange symmetry. This is done in the presence of an arbitrary Majorana phase which serves to insure the ... More
Exploration of a physical picture for the QCD scalar channelOct 25 2008A generalized linear sigma model is employed to study the quark structure of low lying scalar as well as pseudoscalar states. The model allows the possible mixing of quark anti-quark states with others made of two quarks and two antiquarks but no a priori ... More
Low energy scattering with a nontrivial pionAug 24 2007An earlier calculation in a generalized linear sigma model showed that the well-known current algebra formula for low energy pion pion scattering held even though the massless Nambu Goldstone pion contained a small admixture of a two-quark two-antiquark ... More
Toy model for two chiral nonetsJun 16 2005Jul 27 2005Motivated by the possibility that nonets of scalar mesons might be described as mixtures of "two quark" and "four quark" components, we further study a toy model in which corresponding chiral nonets (containing also the pseudoscalar partners) interact ... More
Quark and glue spectroscopy of scalars and pseudoscalars in SU(3) flavor limitOct 24 2018Within the framework of the generalized linear sigma model with glueballs recently proposed [1,2], we study the schematic spectroscopy of scalar and pseudoscalar mesons in the SU(3) flavor limit and explore their quark and glue contents. In this framework, ... More
Why are there three generations of fermions in the standard model?Dec 24 2014We show that by decomposing the gauge fields in fermion degrees of freedom and by saturating the remaining degrees of freedom as dynamical fields in the Lagrangian one might explain the proliferation of fermion states in the standard model Lagrangian. ... More
A top condensate model with a Higgs doublet and a Higgs tripletApr 26 2013We reconsider top condensate models from the perspective that not only two quark composite fields can form but also four quark ones. We obtain a model which contains a Higgs doublet and a Higgs triplet, where one of the neutral components of the Higgs ... More
Light Scalar Puzzle in QCDMay 25 2010An approach to understanding the light scalar meson phenomenology is briefly reviewed.
Global aspects of the scalar meson puzzleFeb 17 2009A generalized linear sigma model for low energy QCD is employed to study the quark structure of eight low lying scalar isomultiplets as well as eight low lying pseudoscalar isomultiplets. The model, building on earlier work, assumes the possible mixing ... More
Scalar mesons from an effective Lagrangian approachNov 14 2007Jan 16 2008A brief discussion of the recent interest in light scalar mesons motivates the study of a generalized linear sigma model. In an SU(3) flavor invariant version of the model there is a prediction that the the lighter scalars have sizeable "four quark" content. ... More
Are three flavors special?Dec 22 2010It has become clearer recently that the regular pattern of three flavor nonets describing the low spin meson multiplets seems to require some modification for the case of the spin 0 scalar mesons. One picture which has had some success, treats the scalars ... More
A theoretical analysis of the doubly radiative rare decays $η^{(\prime)}\toπ^0γγ$ and $η^\prime\toηγγ$Dec 20 2018The rare, doubly radiative decays $\eta^{(\prime)}\to\pi^0\gamma\gamma$ and $\eta^\prime\to\eta\gamma\gamma$ are analysed in terms of scalar and vector meson exchange contributions using the frameworks of the Linear Sigma Model and Vector Meson Dominance, ... More
Chiral Nonet Mixing in pi pi ScatteringJun 22 2011Pion pion scattering is studied in a generalized linear sigma model which contains two scalar nonets (one of quark-antiquark type and the other of diquark-antidiquark type) and two corresponding pseudoscalar nonets. An interesting feature concerns the ... More
Probing scalar mesons in semi-leptonic decays of $D_s^+$, $D^+$ and $D^0$Jul 27 2014With the primary motivation of probing the quark substructure of scalar mesons, a generalized linear sigma model for the lowest and the next-to-lowest scalar and pseudoscalar mesons is employed to investigate several semi-leptonic decays of $D$ mesons. ... More
Semi-leptonic $D_s^+$(1968) decays as a scalar meson probeAug 17 2011The unusual multiplet structures associated with the light spin zero mesons have recently attracted a good deal of theoretical attention. Here we discuss some aspects associated with the possibility of getting new experimental information on this topic ... More
The Action with Manifest E7 Type SymmetryDec 19 2018Mar 14 2019We generalize Cremmer-Julia 1st order action of $N=8$ supergravity with manifest $E_{7(7)}$, symmetry to cases of $N=6$ with manifest $SO^*(12)$ and $N=5$ with manifest $SU(1,5)$ duality symmetries. These U dualities belong to groups of type E7 which ... More
Nonlinear (Super)Symmetries and AmplitudesSep 28 2016There is an increasing interest in nonlinear supersymmetries in cosmological model building. Independently, elegant expressions for the all-tree amplitudes in models with nonlinear symmetries, like D3 brane Dirac-Born-Infeld-Volkov-Akulov theory, were ... More
Deformation, non-commutativity and the cosmological constant problemMay 26 2004In this talk we provide arguments on possible relation between the cosmological constant in our space and the non-commutativity parameter of the internal space of compactified string theory. The arguments are valid in the context of D3/D7 brane cosmological ... More
Supergravity, M theory and CosmologyMay 30 2002We discuss some recent attempts to reconcile cosmology with supergravity and M/string theory. First of all, we point out that in extended supergravities the scalar masses are quantized in terms of the cosmological constant in de Sitter vacua: the eigenvalues ... More
Quantization of p-branes, D-p-branes and M-branesSep 29 1997Killing spinors of space-time BPS configurations play an important role in quantization of theories with the fermionic worldvolume local symmetry. We show here how it works for the GS superstring, BST supermembrane and M-5-brane. We show that the non-linear ... More
BLACK HOLE MULTIPLETS AND SPONTANEOUS BREAKING OF LOCAL SUPERSYMMETRYMar 06 1995We classify states saturating a double or a single supersymmetric positivity bound of a four-dimensional N=4 supersymmetry. The massive four-dimensional double-bound states (Bogomolny states) are shown to form a light-like representation of ten-dimensional ... More
Axion-Dilaton Black HolesMar 19 1993In this talk some essential features of stringy black holes are described. We consider charged four-dimensional axion-dilaton black holes. The Hawking temperature and the entropy of all solutions are shown to be simple functions of the squares of supercharges, ... More
An Implementation, Empirical Evaluation and Proposed Improvement for Bidirectional Splitting Method for Argumentation Frameworks under Stable SemanticsAug 11 2018Abstract argumentation frameworks are formal systems that facilitate obtaining conclusions from non-monotonic knowledge systems. Within such a system, an argumentation semantics is defined as a set of arguments with some desired qualities, for example, ... More
Remark on pion scattering lengthsApr 14 2009Jul 29 2009First it is shown that the tree amplitude for pion pion scattering in the minimal linear sigma model has an exact expression which is proportional to a geometric series in the quantity (s-$m_\pi^2$)/($m_B^2-m_\pi^2$), where $m_B$ is the sigma mass which ... More
Nonlinear (Super)Symmetries and AmplitudesSep 28 2016Oct 06 2016There is an increasing interest in nonlinear supersymmetries in cosmological model building. Independently, elegant expressions for the all-tree amplitudes in models with nonlinear symmetries, like D3 brane Dirac-Born-Infeld-Volkov-Akulov theory, were ... More
On solving the densest $k$-subgraph problem on large graphsJan 18 2019The densest $k$-subgraph problem is the problem of finding a $k$-vertex subgraph of a graph with the maximum number of edges. In order to solve large instances of the densest $k$-subgraph problem, we introduce two algorithms that are based on the random ... More
An Update on Perturbative N=8 SupergravityDec 22 2014According to the recent pure spinor analysis of the UV divergences by Karlsson, there are no divergent 1PI structures beyond 6 loops in D=4 N=8 supergravity. In combination with the common expectation that the UV divergences do not appear at less than ... More
More on Universal Superconformal AttractorsFeb 13 2014We define a general class of superconformal inflationary attractor models studied in our previous papers [1,2], which include, among others, inflationary models of 'induced gravity' which were argued to retain perturbative unitarity up to the Planck scale ... More
Local DiagnosisMar 10 2000In an earlier work, we have presented operations of belief change which only affect the relevant part of a belief base. In this paper, we propose the application of the same strategy to the problem of model-based diangosis. We first isolate the subset ... More
Multivalued Entropy of Supersymmetric Black HolesDec 07 1999The supersymmetric flow equations describing the flow of moduli from infinity to the black hole horizon, and vice versa, are derived in the five-dimensional theories where the moduli space of the very special geometry has disjoint branches. The multiple ... More
Superconformal Actions in Killing GaugeJul 28 1998The classical superconformal actions of branes in adS superspaces have a closed form depending on a matrix $M^2$ quadratic in fermions, as found in hep-th/9805217. One can gauge-fix the local $\kappa$-symmetry using the Killing spinors of the brane in ... More
Duality Symmetric Quantization of SuperstringJun 19 1995A general covariant quantization of superparticle, Green-Schwarz superstring and a supermembrane with manifest supersymmetry and duality symmetry is proposed. This quantization provides a natural quantum mechanical description of curved BPS-type backgrounds ... More