# Pierre RamondUniversity of Florida | UF · Department of Physics

Pierre Ramond

PhD

## About

165

Publications

11,883

Reads

**How we measure 'reads'**

A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more

11,800

Citations

Citations since 2017

Introduction

**Skills and Expertise**

## Publications

Publications (165)

We extend the recently proposed SU(5)×T13 model for the asymmetric texture to the up-type quark and seesaw sectors. The hierarchical up-type quark masses are generated from higher-dimensional operators involving family-singlet Higgses, gauge-singlet familons, and vectorlike messengers. The complex-tribimaximal seesaw mixing arises from the vacuum s...

We extend the recently proposed $SU(5) \times \mathcal{T}_{13}$ model for the asymmetric texture to the up-type quark and Seesaw sectors. The hierarchical up-type quark masses are generated from higher-dimensional operators involving family-singlet Higgses, gauge-singlet familons, and vector-like messengers. The complex-Tribimaximal (TBM) Seesaw mi...

We propose T13=Z13⋊Z3 as the underlying non-Abelian discrete family symmetry of the asymmetric texture presented in [M. H. Rahat, P. Ramond, and B. Xu, Phys. Rev. D 98, 055030 (2018).]. Its mod 13 arithmetic distinguishes each Yukawa matrix element of the texture. We construct a model of effective interactions that singles out the asymmetry and equ...

We propose $\mathcal{T}_{13} = \mathcal{Z}_{13} \rtimes \mathcal{Z}_3$ as the underlying nonabelian discrete family symmetry of the asymmetric texture presented in arXiv:1805.10684 [hep-ph]. Its mod 13 arithmetic distinguishes each Yukawa matrix element of the texture. We construct a model of effective interactions that singles out the asymmetry an...

We construct a texture where the seesaw matrix is diagonalized by the tribimaximal (TBM) matrix with a phase. All angles of the Cabibbo-Kobayashi-Maskawa matrix and Pontecorvo-Maki-Nakagawa-Sakata matrix are consistent with particle data group values, and the mass relations of quarks and charged leptons extrapolated to the grand unified theory scal...

Attention is drawn to a finely tuned Seesaw Majorana matrix linked to the
charge $2/3$ quarks hierarchy. With a diagonal Dirac neutrino matrix, it gives
tribimaximal mixing, and a normal hierarchy for the light neutrinos. We present
a model with the family group $\mathcal{PSL}_2(7)$ where this Majorana matrix
is natural, and the top quark hierarchy...

We present the results of a numerical search for the Dirac Yukawa matrices of
the Standard Model, consistent with the quark and lepton masses and their
mixing angles. We assume a diagonal up-quark matrix, (natural in $\bs{\m Z_7
\rtimes \m Z_3}$), Bimaximal or Tri-bimaximal seesaw mixing, and $SU(5)$
unification to relate the down-quark and charged...

We describe the early evolution of theories with fermion-boson symmetry

These reports present the results of the 2013 Community Summer Study of the
APS Division of Particles and Fields ("Snowmass 2013") on the future program of
particle physics in the U.S. Chapter 1 contains the Executive Summary and the
summaries of the reports of the nine working groups.

This is a set of five elementary lectures which describe the basics of
the Standard Model and its extensions to neutrino masses and also to
Grand-Unification.

We present a model in which the Supersymmetric Standard Model is aug-mented by the family symmetry \( {{\mathcal{Z}}_7} \rtimes {{\mathcal{Z}}_3} \). Motivated by SO(10), where the charge two-thirds and neutral Dirac Yukawa matrices are related, we propose, using family symmetry, a special form for the seesaw Majorana matrix; it contains a squared...

In this paper delivered by Murray Gell-Mann at the Stony Brook Supergravity
Workshop in 1979, several paths to unification are discussed, from N=8
supergravity to $SU_5$, $SO_{10}$, and $E_6$. Generalizations of $SO_{10}$ to
spinor representations of larger groups are introduced. A natural mechanism for
generating tiny neutrino masses is proposed i...

We present a toy model in which the Higgs sector fields transform as
non-Abelian representations of a family symmetry group, and consider the
possibility that the extra family partners of the Higgs particles act as
messengers for both supersymmetry and family symmetry breakings. Although such
mediation schemes generically produce family dependent s...

The SuperConformal theory in three space-time dimensions with SO(16) R-symmetry, 128 bosons and 128 fermions cannot sustain interactions. This result is obtained using both light-cone superspace techniques which rely on algebraic consistency, and co-variant methods which rely on SO(16) Fierz identities which fail to produce the desired algebra.

We relate the MNS and CKM mixing matrices using ideas from grand unification. We catalog models in terms of the family symmetries of the down quark mass matrices, and emphasize the role of the Cabibbo angle in the lepton mixing matrix. We find a large class of models with an observable CHOOZ angle .

The recently formulated Bagger-Lambert-Gustavsson (BLG) theory in three dimensions is described in terms of a constrained chiral superfield in light-cone superspace. We discuss the use of Superconformal symmetry to determine the form of its interactions, in complete analogy with N = 4 SuperYang-Mills in four dimensions.

Five elementary lectures delivered at TASI 2011 on the Standard Model, its
extensions to neutrino masses, flavor symmetries, and Grand-Unification.

In ten dimensions, SO(8) triality encourages confusion between fermions ans bosons, but in eleven dimensions, SO(9) has no such features. Yet this is the domain of M — theory whose infrared limit is the divergent supergravity field theory. Curtright ascribes this divergence to an incomplete cancellation among the Dynkin indices between the supergra...

Group theory has long been an important computational tool for physicists, but, with the advent of the Standard Model, it has become a powerful conceptual tool as well. This book introduces physicists to many of the fascinating mathematical aspects of group theory, and mathematicians to its physics applications. Designed for advanced undergraduate...

We give a relatively simple explanation of the light-cone supergraph prediction for the UV properties of the maximally supersymmetric theories. It is based on the existence of a dynamical supersymmetry which is not manifest in the light-cone supergraphs. It suggests that N=4 supersymmetric Yang-Mills theory is UV finite and N=8 supergravity is UV f...

The light-cone superspace version of the d=3, N=8 superconformal theory of Bagger, Lambert and Gustavsson (BLG) is obtained as a solution to constraints imposed by OSp(2,2|8) superalgebra. The Hamiltonian of the theory is shown to be a quadratic form of the dynamical supersymmetry transformation. Comment: 45 pages, v2: reference added, minor typos...

Assuming that finite family symmetries are gauged, we derive discrete anomaly conditions for various non-Abelian groups. We thus provide new constraints for flavor model building, in which discrete non-Abelian symmetries are employed to explain the tri-bimaximal mixing pattern in the lepton sector.

We use the Cremmer-Julia E7(7) non-linear symmetry of = 8 Supergravity to derive its order κ2 on-shell
Hamiltonian in terms of one chiral light-cone superfield. By
requiring that E7(7) commute with the super-Poincaré group, we
deduce to lowest non-trivial order in κ, the light cone E7(7)
transformations of all fields of the theory, including the gr...

We derive the non-linear action of E8(8) on the constrained chiral superfield in the light-cone superspace with eight complex Grassmann variables. We construct (to lowest order in the coupling) the sixteen dynamical supersymmetries which generate a Hamiltonian with E8(8) invariance in three space-time dimensions, and show that it has only interacti...

We construct all quintic invariants in five variables with simple Non-Abelian finite symmetry groups. These define Calabi-Yau three-folds which are left invariant by the action of A_5, A_6 or PSL_2(11).

111 pages, 23 figures.-- ISI Article Identifier: 000250727500002.-- ArXiv pre-print available at: http://arxiv.org/abs/hep-ph/0510213 Printed version published in Nov 2007. This paper is a review of the present status of neutrino mass physics, which grew out of an APS sponsored study of neutrinos in 2004. After a discussion of the present knowledge...

The recently measured unexpected neutrino mixing patterns have caused a resurgence of interest in the study of finite flavor groups with two- and three-dimensional irreducible representations. This paper details the mathematics of the two finite simple groups with such representations, the Icosahedral group A_5, a subgroup of SO(3), and PSL_2(7), a...

The large neutrino mixing angles have generated interest in finite subgroups of SU(3), as clues towards understanding the flavor structure of the standard model. In this work, we study the mathematical structure of the simplest non-Abelian subgroup, Δ(3n2). Using simple mathematical techniques, we derive its conjugacy classes and character table, a...

The non-Abelian finite group PSL2(7) is the only simple subgroup of SU(3) with a complex three-dimensional irreducible representation. It has two maximal subgroups, S4 which, along with its own A4 subgroup, has been successfully applied in numerous models of flavor, as well as the 21 element Frobenius group Z7⋊Z3, which has gained much less attenti...

The large neutrino mixing angles have generated interest in finite subgroups of SU (3), as clues towards understanding the flavor structure of the Standard Model. In this work, we study the mathematical structure of the simplest non-Abelian subgroup, ∆(3n 2). Using simple mathematical techniques, we derive its conju-gacy classes, character table, b...

We review the construction of the free equations of motion for open and closed strings in 26 dimensions, using the methods of the Florida Group. Differing from previous treatments, we argue that the constraint L0 - 0 = 0 should not be imposed on all the fields of the closed string in the gauge invariant formalism; we show that it can be incorporate...

The Large Hadron Collider at CERN is due to begin operation at the end of 2007 opening a new energy frontier in particle physics. The LHC is ultimately expected to operate at L=10E34 cm2/s and the CMS detector has been designed to cope with the high radiation and event rates expected at this luminosity. However, after several years of running at th...

CMS is a general purpose experiment, designed to study the physics of pp collisions at 14 TeV at the Large Hadron Collider ( LHC). It currently involves more than 2000 physicists from more than 150 institutes and 37 countries. The LHC will provide extraordinary opportunities for particle physics based on its unprecedented collision energy and lumin...

This report presents the capabilities of the CMS experiment to explore the rich heavy-ion physics programme offered by the CERN Large Hadron Collider (LHC). The collisions of lead nuclei at energies , will probe quark and gluon matter at unprecedented values of energy density. The prime goal of this research is to study the fundamental theory of th...

Within the broad context of quark-lepton unification, we investigate the implications of broken continuous family symmetries which result from requiring that in the limit of exact symmetry, the Dirac mass matrices yield hierarchical masses for the quarks and charged leptons, but lead to degenerate light neutrino masses as a consequence of the seesa...

The wealth of new data on neutrinos is easily incorporated in the Electroweak Theory. In this "ν-Standard Model", lepton mixings are distinguished from quark mixings by a unitary matrix coming from the Seesaw. We catalog models in terms of the number of large angles (one or two) in that matrix. Pati-Salam unification implies Cabibbo effects in lept...

Since neutrinos are the only elementary particles that interact only weakly, the study of their properties, albeit experimentally difficult, reflects the true nature of the Weak Interactions. We begin with a historical review, emphasizing the central role of neutrinos in the formulation of the Standard Model. We review the generalizations of the St...

The symmetries of the N=4 super-Yang–Mills theory on the light-cone are discussed, solely in terms of its physical degrees of freedom. We derive explicit expressions for the generators of the PSU(2,2|4) superalgebra, both in the free theory, and to all orders in the gauge coupling of the classical theory. We use these symmetries to construct its Ha...

Quark lepton unification suggests Cabibbo-sized effects in lepton
mixings, which we call Cabibbo haze. We give simple examples and explore
possible Wolfenstein-like parametrizations of the MNSP matrix which
incorporate leptonic Cabibbo shifts. We find that the size of the CHOOZ
angle is not always correlated with the observability of CP violation.

We show that Supergravity in eleven dimensions can be
described in terms of a constrained superfield on the light-cone,
without the use of auxiliary fields. We build its action to
first order in the gravitational coupling constant κ, by
``oxidizing" ( = 8 ,d = 4) Supergravity. This is simply
achieved, as for = 4 Yang-Mills, by extending the
transve...

After a brief overview of the present knowledge of neutrino masses and mixing, we summarize what can be learned about physics beyond the standard model from the various proposed neutrino experiments. We also comment on the impact of the experiments on our understanding of the origin of the matter-antimatter asymmetry of the Universe as well as what...

The prediction of small neutrino masses through the Seesaw Mechanism and their subsequent measurement suggests that the natural cut-off of the Standard Model is very high indeed. The recent neutrino data must be interpreted as a reflection of physics at very high energy. We examine their implications in terms of ideas of Grand Unification and Super...

While most theorists are tied to the mast of four dimensions, some have found it irresistible to speculate about eleven dimensions, the domain of M-theory. We outline a program which starts from the light-cone description of supergravity, and tracks its divergences to suggest the existence of an infinite component theory which in the light-cone rel...

The Seesaw mechanism predicted tiny neutrino masses by postulating a new large scale in particle physics, using new theoretical ideas prompted by the Standard Model. It adds credence to a theoretical vista that is a quarter century old, and fits with the most endearing speculations of ultimate unification. By relating the measurement of static neut...

We consider how the continuous spin representation (CSR) of the Poincare group in four dimensions can be generated by dimensional reduction. The analysis uses the front-form little group in five dimensions, which must yield the Euclidean group E(2), the little group of the CSR. We consider two cases, one is the single spin massless representation o...

We introduce superspace generalizations of the transverse derivatives to rewrite the four-dimensional N = 4 Yang-Mills theory into the fully ten-dimensional N = 1 Yang-Mills in light-cone form. The explicit SuperPoincaré algebra is constructed and invariance of the ten-dimensional action is proved.

After recalling some elegant contributions of the late Freydoon Mansouri, we turn to neutrino physics and use a {\it modicum} of grand unification to relate quark and lepton mixing matrices. We advocate an expansion for the MNS matrix, {\it \`a la} Wolfenstein, and argue that in a wide class of models, $\theta_{13}$ is a Cabibbo mixing effect. Also...

One hundred years after its creator's birth, the Dirac equation stands as the cornerstone of XXth Century physics. But it is much more, as it carries the seeds of supersymmetry. Dirac also invented the light-cone, or "front form" dynamics, which plays a crucial role in string theory and in elucidating the finiteness of N = 4 Yang-Mills theory. The...

We introduce a new parametrization of the MNS lepton mixing matrix which separates the hierarchical grand unified relations among quarks and leptons. We argue that one large angle stems from the charged leptons, the other from the seesaw structure of the neutral lepton mass matrix. We show how two large mixing angles can arise naturally provided th...

We investigate symmetry breaking patterns from replicated gauge groups which generate anomaly-free and family-dependent U(1) symmetries. We discuss the extent to which these symmetries can explain the observed hierarchies of fermion masses and mixings. Comment: 25 pages

Quarks and leptons charges and interactions are derived from gauge theories associated with symmetries. Their space-time labels come from representations of the non-compact algebra of Special Relativity. Common to these descriptions are the Lie groups stemming from their invariances. Does Nature use Exceptional Groups, the most distinctive among th...

We construct Wigner's continuous spin representations of the Poincaré algebra for massless particles in higher dimensions. The states are labeled both by the length of a spacelike translation vector and the Dynkin indices of the short little group SO(d-3), where d is the space-time dimension. Continuous spin representations are in one-to-one corres...

Some massless supermultiplets appear as the trivial solution of Kostant's equation, a Dirac-like equation over special cosets. We study two examples; one over the coset SU(3)/SU(2) × U(1) contains the N = 2 hypermultiplet in (3+1) dimensions with U(1) as helicity; the other over the coset F4/SO(9) describes the N = 1 supermultiplet in eleven dimens...

Some massless supermultiplets appear as the trivial solution of Kostant's equation, a Dirac-like equation over special cosets. We study two examples; one over the coset SU(3)/SU(2) × U(1) contains the N = 2 hypermultiplet in (3 + 1) dimensions with U(1) as helicity; the other over the coset F 4/SO(9) describes the N = 1 supermultiplet in eleven dim...

The recent neutrino data seem to favor two large and one small mixing angles and a hierarchy of their squared mass differences. We discuss these within the context of hierarchical neutrino masses. We show that this scheme suggests a specific neutrino mass matrix with mild fine-tuning. We then present a Froggatt–Nielsen model that reproduces this ma...

Nature's attraction to unique mathematical structures provides powerful hints for unraveling her mysteries. None is at present as intriguing as eleven-dimensional M-theory. The search for exceptional structures specific to eleven dimensions leads us to exceptional groups in the description of space-time. One specific connection, through the coset $...

A gauged phase symmetry with its anomalies cancelled by a Green-Schwarz mechanism, broken at a large scale by an induced Fayet-Iliopoulos
term, is a generic feature of a large class of superstring theories. It induces many desirable phenomenological features:
Yukawa coupling hierarchy, the emergence of a small Cabibbo-like expansion parameter, rela...

Fundamental questions in neutrino physics are likely to be resolved by upcoming experiments. Neutrino masses require either new Higgs particles or sterile neutrinos. Their masses, couplings, and habitat are yet to be determined. Neutrino physics is particularly sensitive to brane ideas as the extra particles are electroweak singlets and may free-ra...

Reminiscences on the String origins of Supersymmetry are followed by a discussion of the importance of confusing bosons with fermions in building superstring theories in 9 + 1 dimensions. In eleven dimensions, the kinship between bosons and fermions is more subtle, and may involve the exceptional group F4.

A plausible explanation for the existence of additional light sterile neutrinos is that they correspond to modulini, fermionic partners of moduli, which propagate in new large dimensions. We discuss the phenomenological implications of such states and show that solar neutrino oscillation is well described by small angle MSW oscillation to the tower...

We present a comprehensive study of five-dimensional brane-world models for neutrino physics based on flat compactifications. Particular emphasis is put on the inclusion of bulk mass terms. We derive a number of general results for such brane-world models with bulk mass terms. In particular, in the limit of small brane-bulk couplings, the electrowe...

After a short historical review, the present experimental situation is reviewed and several theoretical schemes are discussed, including a general description of Kaluza-Klein sterile neutrino towers. © 2000 American Institute of Physics.

Certain static soliton configurations of gauge fields in 4+1 dimensions correspond to the instanton in 4 Euclidean dimensions “turned on its side”, becoming a monopole in 4+1. The periodic instanton solution can be used with the method of images to construct solutions satisfying D-brane boundary conditions. The θ-term on the brane becomes a topolog...

The central role of neutrinos in the determination of fundamental interactions is reviewed. The recent SuperKamiokande discovery of neutrino mass gives an ç of physics at short distances, and tests theories of flavor. Quark-lepton symmetries, derived from grand unification and/or string theories, can help determine the standard model parameters in...

No abstract appeared in the Proceedings, but I am adding the following summary at the request of the X^3 people: The idea of neutrino masses is discussed in the context of grand unified theories., and various scenarios are presented, including the seesaw mechanism. At the end, preference is stated for maximal mixing between $\nu_\mu$ and $\nu_\tau$...

The recent discovery by SuperKamiokande of evidence for neutrino masses requires the addition of at least seven new parameters to the Standard Model. We discuss the general theoretical schemes which require their inclusion, and point out how quark-lepton symmetries, either in the framework of Grand Unification, or of string theories, can be used to...

We discuss current theoretical and experimental issues associated with the recent SuperKamiokande discovery. We survey theoretical models for predictings the new Standard Model parameters needed to explain this discovery, and point out how quark-lepton symmetries, either in the framework of Grand Unification, or of string theories, can be used to d...

Current theoretical and experimental issues are reviewed in the light of the recent SuperKamiokande discovery. By using quark-lepton symmetries, derived from Grand Unification and/or string theories, we show how to determine the necessary neutrino parameters. In addition, the seesaw neutrino masses set the scale for the proton decay operators by ``...

After a brief historical survey that emphasizes the role of the algebra obeyed by the Dirac operator, we examine an algebraic Dirac operator associated with Lie algebras and Lie algebra cosets. For symmetric cosets, its ``massless'' solutions display non-relativistic supersymmetry, and can be identified with the massless degrees of freedom of some...

The light-cone little group, SO(9), classifies the massless degrees of freedom of 11-dimensional supergravity, with a triplet of representations. We observe that this triplet generalizes to four-fold infinite families with the quantum numbers of massless higher spin states. Their mathematical structure stems from the three equivalent ways of embedd...

We review the known ways of incorporating and breaking symmetries in a renormalizable way. We summarize the various grand unified theories based on $SU_5, SO_{10}$, and $E_6$ as family enlargement groups. An $SU_5$ model with an $SU_2$ gauged family group is presented as an illustration. In it, the e-family (i.e., e,u and d) is classically massless...

We present a model which contains three Abelian symmetries beyond the standard model. One is anomalous {\it \` a la} Green-Schwarz, and family-independent; the other two are family symmetries. All are broken at a large scale by stringy effects. The model is predictive in the neutrino sector: large mixing between $\nu_\mu-\nu_\tau$, and {\cal O}$(\l...

After a review of the early history of neutrinos and their detection, we analyze the different types of models that extend the standard model to massive neutrinos. We emphasize the generic nature of maximal mixing between muon and tau neutrinos, given simple assumptions based on grand unification. Comment: Latex, 11 pages. Invited Talk at Neutrino-...

Let B be a reductive Lie subalgebra of a semi-simple Lie algebra F of the same rank both over the complex numbers. To each finite dimensional irreducible representation Vlambda of F we assign a multiplet of irreducible representations of B with m elements in each multiplet, where m is the index of the Weyl group of B in the Weyl group of F. We obta...

We discuss, in the context of the strongly coupled E_8 \times E_8 heterotic string proposed by Horava and Witten, the appearance of anomalous U(1)_X symmetries of a nonperturbative origin, related to the presence, after compactification, of five-branes in the five-dimensional bulk of the theory. We compute the gauge anomalies and the induced Fayet-...

The observed quark hierarchies suggest a simple family symmetry. Generalized to leptons through grand-unified quantum numbers, it produces a neutrino mixing matrix with order-one \nu_{\mu} - \nu_{\tau} mixing, and order-\lambda^3 \nu_e - \nu_{\mu} and \nu_e - \nu_{\tau} mixings. The intrafamily hierarchy and observed neutrino mass differences toget...

We present a supersymmetric standard model with three gauged Abelian symmetries, of a type commonly found in superstrings. One is anomalous, the other two are $E_6$ family symmetries. It has a vacuum in which only these symmetries are broken by stringy effects. It reproduces all observed quark and charged lepton Yukawa hierarchies, and the value of...

We present a model for the observed hierarchies among the Yukawa couplings of the standard model in the context of an effective low enegy theory with an anomalous U(1) symmetry. This symmetry, a generic feature of superstring compactification, is a remnant of the Green-Schwarz anomaly cancellation mechanism. The gauge group is that of the standard...

The author catalogs models with massive neutrinos, emphasizing their uses as probes of physics beyond the standard model. He discusses their experimental implications, in terms of neutrino oscillations and the MSW effect.

In models with an anomalous abelian symmetry broken at a very large scale, we study which requirements to impose on the anomalous charges in order to prevent standard model fields from acquiring large vacuum expectation values. The use of holomorphic invariants to study D-flat directions for the anomalous symmetry, proves to be a very powerful tool...

We show that models with an Abelian family symmetry which accounts for the observed hierarchies of masses and mixings in the quark sector may also accommodate quasi-degeneracies in the neutrino mass spectrum. Such approximate degeneracies are, in this context, associated with large mixing angles. The parameters of this class of models are constrain...

N = 1 supersymmetric gauge theories with global flavor symmetries contain a gauge invariant W-superalgebra which acts on its moduli space of gauge invariants. With adjoint matter, this superalgebra reduces to a graded Lie algebra. When the gauge group is SO(nc), with vector matter, it is a W-algebra, and the primary invariants form one of its repre...

The observed hierarchy of quark and lepton masses and mixings may be obtained by adding an abelian family symmetry to the Minimal Supersymmetric Model and coupling quarks and leptons to an electroweak singlet scalar field. In a large class of such models, this symmetry suffers from anomalies which must be compensated by the Green-Schwarz mechanism;...

The addition of an Abelian family symmetry to the Minimal Super-symmetric Standard Model reproduces the observed hierarchies of quark and lepton masses and quark mixing angles, only if it is anomalous. Green-Schwarz compensation of its anomalies requires the electroweak mixing angle to be sin{sup 2}{theta}{sub {omega}} = 3/8 at the string scale, wi...

We augment the Minimal Supersymmetric Standard Model with a gauged family-dependent U(1) to reproduce Yukawa textures compatible with experiment. In the simplest model with one extra chiral electroweak singlet field, acceptable textures require this U(1) to be anomalous. The cancellation of its anomalies by a generic Green-Schwarz mechanism require...

The differences between the $N=0$ and $N=1$ standard models are emphasized in formulating their short distance extension. We sketch methods to reproduce many of the small numbers in the model in terms of scale ratios, applying see-saw like ideas to the breaking of chiral symmetries. We sketch how the $N=1$ standard model, outfitted with an extra fa...

In the minimal supersymmetric standard model, the three gauge couplings appear to unify at a mass scale near $2 \times 10^{16}$ GeV. We investigate the possibility that intermediate scale particle thresholds modify the running couplings so as to increase the unification scale. By requiring consistency of this scenario, we derive some constraints on...

In this paper we summarize the minimal supersymmetric standard model as well as the renormalization group equations of its parameters. We proceed to examine the feasibility of the model when the breaking of supersymmetry is parametrized by the soft terms suggested by supergravity theories. In such models, the electroweak symmetry is exact at the tr...

During the workshop, sponsored by the Institute for Fundamental Theory
(IFT), various questions were discussed associated with dark matter, its
nature, its abundance, and its detection.

We present partial numerical results in the Minimal Supersymmetric Standard Model with soft breaking of supersymmetry, and radiative breaking of the electroweak symmetry. We impose the additional relation, bottom mass = tau mass at the GUT scale. For the special case of the strict no-scale model, in which global supersymmetry breaking arises solely...

The supersymmetric standard model with supergravity-inspired soft breaking
terms predicts a rich pectrum of sparticles to be discovered at the SSC, LHC
and NLC. Because there are more supersymmetric particles than unknown
parameters, one can write down sum rules relating their masses. We discuss the
pectrum of sparticles from this point of view. So...

We develop a systematic analysis of quark mass matrices which, starting with the measured values of quark masses and mixing angles, allows for a model independent search for all possible (symmetric or hermitian) mass matrices having texture zeroes at the unification scale. A survey of all six and five texture zero structures yields a total of five...

In this paper we present a comprehensive analysis of the running of all the couplings of the standard model to two loops, including threshold effects. Our purpose is twofold-to determine what the running of these parameters may indicate for the physics of the standard model and to provide a template for the study of its extensions up to the Planck...