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S. V. Troitsky

Publications and source records attributed to S. V. Troitsky.

89 records · Page 5Linked to original sources
arXiv2000

Three generations on a local vortex in extra dimensions

We develop an approach to the origin of three generations of the Standard Model fermions from one generation in a higher-dimensional theory, where four-dimensional fermions appear as zero modes trapped in the core of a topological defect, and the hierarchy of masses and mixings is produced by wave function overlaps in extra dimensions. We present a model with unbroken U(1) symmetry where three zero modes appear on an Abrikosov-Nielsen-Olesen vortex due to nontrivial scalar--fermion interactions.

hep-ph↗
arXiv2000

Three fermionic generations on a topological defect in extra dimensions

We suggest a mechanism explaining the origin of three generations of the Standard Model fermions from one generation in a higher-dimensional theory. Four-dimensional fermions appear as zero modes trapped in the core of a topological defect with topological number three. We discuss hierarchical pattern of masses and mixings which arises in these models.

hep-ph↗
arXiv1999

Neutrino masses from nonstandard supersymmetry breaking terms

Naturally small Majorana neutrino masses arise from nonstandard supersymmetry breaking terms. This mechanism works in the minimal supersymmetric framework and does not require extra particles or new mass scales. It could also be responsible for proton decay even in the absence of Grand Unification.

hep-ph↗
arXiv1999

Gauge mechanism of mediation of supersymmetry breaking

Most phenomenologically acceptable supersymmetric models imply breaking of supersymmetry in a separate sector of fields introduced just for this purpose. Supersymmetry breaking is transferred to the Standard Model due to a certain interaction with this additional sector. In this review we disuss one of the popular mechanisms of such mediation with the key role played by the Standard Model gauge interactions. We consider general principles of gauge mediation and give the critical analysis of specific models together with their phenomenological and cosmological implications. We present also basic facts concerning mechanisms of dynamical supersymmetry breaking.

hep-ph↗
arXiv1998

On intersection of domain walls in a supersymmetric model

We consider a classical field configuration, corresponding to intersection of two domain walls in a supersymmetric model, where the field profile for two parallel walls at a finite separation is known explicitly. An approximation to the solution for intersecting walls is constructed for a small angle at the intersection. We find a finite effective length of the intersection region and also an energy, associated with the intersection.

hep-th↗
arXiv1998

Grand unification with gauge mediated supersymmetry breaking

We consider constraints on gauge mediated supersymmetry breaking models imposed by the requirement of grand unification. In particular, we demonstrate several ways to reduce the number of parameters coming from the dynamical supersymmetry breaking sector. One of approaches exploits nonperturbative unification of gauge couplings in multi-messenger models.

hep-ph↗
arXiv1998

Dynamical supersymmetry breaking and unification of couplings

We consider the possibility of unification of the Supersymmetric Standard Model gauge groups with those of the dynamical supersymmetry breaking (DSB) sector in theories with gauge mediated supersymmetry breaking. We find constraints on the DSB gauge group beta function that come from unification of the gauge coupling constants of the two sectors. These constraints are satisfied by a fairly wide class of models. We discuss possible unification scenarios in the context of a simple model.

hep-ph↗
arXiv1998

Towards common origin of supersymmetry breaking, compositeness, and gauge mediation

We present a toy model which has the following properties: i) it is strongly coupled at a certain scale and breaks supersymmetry at this scale; ii) matter superfields of (one generation of) the Standard Model are effective low energy degrees of freedom of this strongly coupled theory; iii) direct gauge mediation of supersymmetry breaking occurs due to messenger superfields that are also effective low energy degrees of freedom. We discuss the way to generalize this approach to realistic models with three generations. These models might be favorable from the point of view of string theory compactifications.

hep-ph↗
arXiv1996

What Becomes of Vortices in Theories with Flat Directions

In many theories with flat directions of scalar potential, static vortex solutions do not exist for a generic choice of vacuum. In two Euclidean dimensions, we find their substitutes --- constrained instantons consisting of compact core formed by Abrikosov--Nielsen--Olesen vortex and long-ranged cloud of modulus field. In (3+1) dimensions, an initial compact configuration of string topology evolves in such a way that at every point in space the modulus relaxes, in a universal manner, to one and the same value characteristic to the theory.

hep-ph↗
arXiv1995

Exponentiation of multiparticle amplitudes in scalar theories. II. Universality of the exponent

It has been shown recently that the amplitude of the creation of $n$ real scalar particles by one virtual boson near $n$--particle threshold exhibits exponential behavior at $n\sim1/λ$. We extend this result to the processes of multiparticle production at threshold by two virtual bosons. We find that both the tree--level amplitude and leading--$n$ loop corrections have the same exponential behavior, with the common exponent for $1\to n$ and $2\to n$ processes, for various kinematics. This result strongly indicates that the exponent for multiparticle amplitudes is independent of the initial state and that there may exist a semiclassical approach to the study of multiparticle production.

hep-ph↗
arXiv1994

Exponentiation of Multiparticle Amplitudes in Scalar Theories

It is argued that the amplitudes of the production of $n$ soft scalar particles by one or a few energetic ones in theories like $λϕ^4$ has the exponential form, $A_n\propto\sqrt{n!}\exp[{1\overλ}F(λn,ε)]$, in the regime $λ\to 0$, $λn={fixed}$, $ε={fixed}$, where $ε$ is the typical kinetic energy of outgoing particles. Existing results support this conjecture. Several new analytical and numerical results in favor of the exponential behavior of multiparticle amplitudes are presented.

hep-ph↗
arXiv1993

Zeros of tree amplitudes at rest and symmetries of mechanical systems

We consider the tree amplitudes of production of $n_2$ scalar particles by $n_1$ particles of another kind, where both initial and final particles are at rest and on mass shell, in a model of two scalar fields with $O(2)$ symmetric interaction and unequal masses. We find that these amplitudes are zero except for the lowest possible $n_1$ and $n_2$, and that the cancellation of the corresponding Feynman graphs occurs due to a special symmetry of the classical mechanical counterpart of this theory. This feature is rather general and is inherent in various other scalar field theories.

hep-ph↗
arXiv1993

Tree amplitudes at multiparticle threshold in a model with softly broken $O(2)$ symmetry

Tree amplitudes of the production of two kinds of scalar particles at threshold from one virtual particle are calculated in a model of two scalar fields with $O(2)$ symmetric quartic interaction and unequal masses. These amplitudes exhibit interesting factorial and exponential behaviour at large multiplicities. As a by-product we observe that the kinematically allowed decay of one real particle into $n$ real particles of another kind, all at rest, has zero tree amplitude in this model for $n>2$.

hep-ph↗