MSSM inflation and cosmological attractors

Inflationary scenarios motivated by the minimal supersymmetric standard model (MSSM) where five scalar fields are non-minimally coupled to gravity are considered. The potential of the model and the function of non-minimal coupling are polynomials of two Higgs doublet convolutions. We show that the use of the strong coupling approximation allows to obtain inflationary parameters in the case when a combination of the four scalar fields plays a role of inflaton. Numerical calculations show that the cosmological evolution leads to inflationary scenarios fully compatible with observational data for different values of the MSSM mixing angle [Formula: see text].

CRITICAL BEHAVIOR OF STRONGLY COUPLED LATTICE QCD AT FINITE TEMPERATURE

We study the critical behavior of lattice Quantum Chromodynamics (QCD) in the strong coupling approximation with Kogut–Susskind and Wilson fermions at finite temperature (T) and zero chemical potential. Using the Hamiltonian formulation we construct a mean field solution to the equation of motion at finite T and use it to study the elementary thermal excitations and to extract some critical exponents characterizing the observed second-order phase transition. We find similar critical behaviors for Kogut–Susskind and Wilson fermions at finite T.

AdS/CFT DUALITY AND THE GLUEBALL SPECTRUM

The complete glueball spectrum for the AdS7 black hole supergravity dual of QCD is shown to bare a striking resemblance to the known lattice results despite the limitations of the strong coupling approximation. Further extensions of duality to couple hadronic matter to gravity in the Randall-Sundram brane world scenario are suggested.

About the Influence of the Square-Root Van Hove Singularity on the Critical Temperature of Overdoped High-Temperature Superconductors

It is shown that the square-root van Hove singularity in the density of states ν(E F )~ (E F -E0)-1/2, associated with the extended saddle-point singularities in the electron spectra of the cuprates, leads to a nonmonotonic dependence of the critical temperature T c on the position of the Fermi level E F with respect to the bottom E0 of the saddle. As a result of cancellation of the divergency of ν(E F ) in the electron–electron coupling constant, renormalized due to the account of the strong coupling effects, T c approaches zero in the limit E F → E0. This result contrasts that of the weak coupling approximation, which gives a finite value of T c for E F → E0. The T c on the concentration of doped holes, obtained in the strong coupling approximation, agrees qualitatively with the experimental data for the overdoped cuprate metal-oxides.