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V. G. Ksenzov

Publications and source records attributed to V. G. Ksenzov.

11 recordsLinked to original sources
arXiv2021

Chiral Condensate in Two Dimensional Models

We investigate two different models. In one of them massive fermions interact with a massive scalar field and in the other the fermion field is in an electrical field (QED2). The chiral condensates are calculated in one-loop approximation. We found that the chiral condensate in the case of the Yukawa interaction the fermions and scalar field does not vanish if the mass of the fermion field tends to zero. The chiral condensate disappears in QED2, if the fermion mass is zero.

hep-ph↗
arXiv2017

Zero Points of Chiral Condensate

We investigate a model with a massless fermion and a massive scalar field with the Yukawa interaction between these two fields. The model possess a discrete symmetry. The chiral condensate is calculated in one-loop approximation in $(1+1)$-dimensional spacetime. It was shown that the chiral condensate vanishes at two different values of the coupling constant. At the first of them there is a phase transition in which the discrete symmetry is restored. At the second zero of the chiral condensate it takes place a phase transition which distinguishes the positive $μ^2$ from the negative $μ^2$, where $μ^2$ is an effective mass of the scalar field.

hep-ph↗
arXiv2015

Chiral condensate beyond one-loop approximation

We study two-dimensional model with a fermion field and a self-interaction scalar field with the Yukawa interaction beyond the framework of the one-loop approximation. We show that in the model besides a phase transitions appear decays of the excited scalar states.

hep-ph↗
arXiv2014

Phase Transitions in Models with Discrete Symmetry

We investigate a class of models with a massless fermion and a self-interacting scalar field with the Yukawa interaction between these two fields. The models considered are formulated in two and four spacetime dimensions and possess a discrete symmetry. We calculate the chiral condensates are calculated in the one-loop approximation. We show that the models have a phase transitions as a function of the coupling constants.

hep-ph↗
arXiv2012

Dynamical Symmetry Breaking in Models with the Yukawa Interaction

We discuss models with a massless fermion and a self-interacting massive scalar field with the Yukawa interaction. The chiral condensate and the fermion mass are calculated analytically. It is shown that the models have a phase transition as a function of the squared mass of the scalar field.

hep-th↗
arXiv2010

Stable branches of a solution for a fermion on domain wall

We discuss the case when a fermion occupies an excited non-zero frequency level in the field of domain wall. We demonstrate that a solution exists for the coupling constant in the limited interval $1<g<g_{max}\approx 1.65$. We show that indeed there are different branches of stable solution for $g$ in this interval. The first one corresponds to a fermion located on the domain wall ($1<g<\sqrt[4]{2π}$). The second branch, which belongs to the interval $\sqrt[4]{2π}\le g\le g_{max}$, describes a polarized fermion off the domain wall. The third branch with $1<g<g_{max}$ describes an excited antifermion in the field of the domain wall.

hep-ph↗
arXiv2010

Example of a self-consistent solution for a fermion on domain wall

We discuss a self-consistent solution for a fermion coupled to static scalar field in the form of a kink (domain wall). In particular, we study the case when the fermion occupies an excited non-zero frequency level in the presence of the domain wall field. The effect of the domain wall profile distortion is calculated analytically.

hep-th↗
arXiv1997

New approach to the non-perturbative physics

It was shown that the non-perturbative properties of the vacuum are described by the quantum fluctuations around the classical background with zero canonical momentum. The vacuum state has been built and checked in the framework of the sigma models in two dimentions.

hep-th↗
arXiv1995

On the Calculation of the Vacuum Energy Density in Sigma Models

The vacuum energy density is calculated for the $O(N)$ nonlinear sigma models in two dimensions. To obtain $\varepsilon_{vac}$ we assume that each point of the space in which non-perturbative f\/ields are determined can be replaced by a sphere $S^2$ having a small radius $r$ which approaches zero at the very end of the calculation. This assumption allows to get the classical f\/ields generating v.e.v. of the trace of the energy-momentum tensor.

hep-th↗