14,612 research outputs found
The evolution of vacuum states and phase transitions in 2HDM during cooling of Universe
We consider the evolution of the ground state in the Two Higgs Doublet Model
during cooling down of the Universe after the Big Bang. Different regions in
the space of free parameters of this model correspond to different sequences of
thermal phase transitions. We discuss different paths of thermal evolution and
corresponding evolution of physical properties of the system for different
modern values of the parameters.Comment: 28 pages, 12 figure
On the two-loop divergences of the 2-point hypermultiplet supergraphs for , SYM theory
We consider , supersymmetric Yang-Mills theory
formulated in harmonic superspace and analyze the structure of
the two-loop divergences in the hypermultiplet sector. Using the superfield background field method we study the two-point supergraphs
with the hypermultiplet legs and prove that their total contribution to the
divergent part of effective action vanishes off shell.Comment: 8 pages, 2 figure
Supergraph analysis of the one-loop divergences in , and gauge theories
We study the one-loop effective action for
supersymmetric Yang--Mills (SYM) theory with hypermultiplets and SYM theory as a subclass of the former, using the off-shell
formulation of these theories in harmonic superspace. We
develop the corresponding supergraph technique and apply it to compute the
one-loop divergences in the background field method ensuring the manifest gauge
invariance. We calculate the two-point Green functions of the gauge superfield
and the hypermultiplet, as well as the three-point gauge-hypermultipet Green
function. Using these Green functions and exploiting gauge invariance of the
theory, we find the full set of the off-shell one-loop divergent contributions,
including the logarithmic and power ones. Our results precisely match with
those obtained earlier in [1,2] within the proper time superfield method.Comment: 32 pages, 5 figure
Joint probability calculation of the lateral velocity distribution in strong field ionization process
We describe an approach to the description of the time-development of the
process of strong field ionization of atoms based on the calculation of the
joint probability of occurrence of two events, event B being finding atom in
the ionized state after the end of the laser pulse, event A being finding a
particular value of a given physical observable at a moment of time inside the
laser pulse duration. As an example of such an physical observable we consider
lateral velocity component of the electron's velocity. Our approach allows us
to study time-evolution of the lateral velocity distribution for the ionized
electron during the interval of the laser pulse duration. We present results of
such a study for the cases of target atomic systems with short range Yukawa and
Coulomb interactions
Quantum internal modes of solitons in 1d easy-plane antiferromagnet in strong magnetic field
In presence of a strong external magnetic field the dynamics of solitons in a
one-dimensional easy-plane Heisenberg antiferromagnet exhibits a number of
peculiarities. Dynamics of internal soliton degrees of freedom is essentially
quantum, and they are strongly coupled to the "translational" mode of soliton
movement. These peculiarities lead to considerable changes in the response
functions of the system which can be detected experimentally.Comment: 8 pages, RevTeX, 6 figures, uses psfig.sty, submitted to PR
Evolution of Universe to the present inert phase
We assume that current state of the Universe can be described by the Inert
Doublet Model, containing two scalar doublets, one of which is responsible for
EWSB and masses of particles and the second one having no couplings to fermions
and being responsible for dark matter. We consider possible evolutions of the
Universe to this state during cooling down of the Universe after inflation. We
found that in the past Universe could pass through phase states having no DM
candidate. In the evolution via such states in addition to a possible EWSB
phase transition (2-nd order) the Universe sustained one 1-st order phase
transition or two phase transitions of the 2-nd order.Comment: 19 pages, 3 figure
Vortex solitons in dispersive nonlinear Kerr type media
We have investigated the nonlinear amplitude vector equation governing the
evolution of optical pulses in optical and UV region. We are normalizing this
equation for the cases of different and equal transverse and longitudinal size
of optical pulses, of week and strong dispersion. This gives us the possibility
to reduce the amplitude equation to different nonlinear evolution equations in
the partial cases. For some of these nonlinear equations exact vortex solutions
are found. Conditions for experimental observations of these vortices are
determined.Comment: 28 pages, 9 figures, Late
- …