Behaviour of a weekly self-interacting scalar eld with a small mass in the de Sitter background is investigated using the stochastic approach (including the case of a double-well interaction potential). Existence of the de Sitter invariant equilibrium quantum state of the scalar eld in the presence of interaction is shown for any sign of the mass term. The stochastic approach is further develop...

Interactions in coupled channels ππ, KK̄ and an effective 2π2π in scalar-isoscalar wave have been analysed. Influence of interchannel couplings on analytical structure of multichannel interaction amplitudes has been studied. Interplay of S-matrix zeroes and poles and their relation with parameters of scalar resonances has been investigated. PACS numbers: 11.80.Gw, 13.60.Le, 13.75.Lb, 14.40.Cs St...

‎Given a compact space $X$ and a commutative Banach algebra‎ ‎$A$‎, ‎the character spaces of $A$-valued function algebras on $X$ are‎ ‎investigated‎. ‎The class of natural $A$-valued function algebras‎, ‎those whose characters can be described by means of characters of $A$ and‎ ‎point evaluation homomorphisms‎, ‎is introduced and studied‎. ‎For an‎ ‎admissible Banach $A$-valued function algebra...

We have studied the formation of relativistic solitary waves due to nonlinearinteraction of strong electromagnetic wave with the plasma wave. Here, our plasma isrelativistic both in temperature and in streaming speed. A set of equations consisting ofscalar and vector potentials together with a third order equation for the enthalpy inphoton gas plasma is obtained analytic...

We study the late time evolution of flat and negatively curved FRW models with a perfect fluid matter source and a scalar field having an arbitrary non-negative potential function V (φ). We prove using a dynamical systems approach four general results for a large class of non-negative potentials which show that almost always the universe ever expands. In particular, for potentials having a loca...

We consider possible dynamical models for a light fermion confined by a potential field. With the Dirac equation only Lorentz scalar confinement yields normalizable wavefunctions, while with the “no pair” variant of the Dirac equation only Lorentz vector confinement has normal Regge behaviour. A systematic investigation of Regge properties and phenomenological properties is carried out, includi...

Abstract The Noether symmetry analysis is applied in a multiscalar field cosmological model teleparallel gravity. In particular, we consider two scalar fields with interaction scalar-torsion theory. equations have minisuperspace description, and the evolution of physical variables depends on potential function that drives fields’ dynamics. With requirement for to admit non-trivial point symmetr...