112 research outputs found
Nonperturbative Physics in a Magnetic Field
Non-Perturbative Quantum Field Theory has played an important role in the
study of phenomena where a fermion condensate can appear under certain physical
conditions. The familiar phenomenon of electric superconductivity, the color
superconductivity of very dense quark matter, and the chiral symmetry breaking
of low energy effective chiral theories are all examples of that sort. Often
one is interested in the behavior of these systems in the presence of an
external magnetic field. In this talk I will outline the effects of an external
magnetic field on theories with either fermion-fermion or fermion-antifermion
condensates.Comment: Invited talk at XII Mexican Workshop on Particles & Fields. Mazatlan,
Sinaloa, Mexico, Nov.200
Yukawa Interactions and Dynamical Generation of Mass in an External Magnetic Field
In this work we study the dynamical generation of a fermion mass induced by a
constant and uniform external magnetic field in an Abelian gauge model with a
Yukawa term. We show that the Yukawa coupling not only enhances the dynamical
generation of the mass, but it substantially decreases the magnetic field
required for the mass to be generated at temperatures comparable to the
electroweak critical temperature. These results indicate that if large enough
primordial magnetic fields were present during the early universe evolution,
the field-induced generation of fermion masses, which in turn corresponds to
the generation of fermion bound states, may play an important role in the
electroweak phase transition.Comment: Corrected mistake in last reference. Work presented at SILAFAE'98, 8
pages. To be published in the proceedings of SILAFAE'98, April 8-11, San
Juan, Puerto Ric
Magnetic Response in Anyon Fluid at High Temperature
The magnetic response of the charged anyon fluid at temperatures lower and
larger than the fermion enery gap is investigated in the
self-consistent field approximation. We prove that the anyon system with
boundaries exhibits a total Meissner effect at temperatures smaller than the
fermion energy gap (). The London penetration length at
is of the order . At a
new phase, characterized by an inhomogeneous magnetic penetration, is found. We
conclude that the energy gap, defines a scale that separates two
phases: a superconducting phase at , and a non-superconducting
one at .Comment: 7 pages, Talk presented at SILAFAE'98. April 8-11, 1998, San Juan,
Puerto Ric
- …