38 research outputs found
Fermion Pairing Dynamics in the Relativistic Scalar Plasma
Using many-body techniques we obtain the time-dependent Gaussian
approximation for interacting fermion-scalar field models. This method is
applied to an uniform system of relativistic spin-1/2 fermion field coupled,
through a Yukawa term, to a scalar field in 3+1 dimensions, the so-called
quantum scalar plasma model. The renormalization for the resulting Gaussian
mean-field equations, both static and dynamical, are examined and initial
conditions discussed. We also investigate solutions for the gap equation and
show that the energy density has a single minimum.Comment: 21 pages, latex, 4 postscript figures, new sections, some literary
changes, notation corrections, accepted for publication in Phys. Rev
On the equivalence principle and gravitational and inertial mass relation of classical charged particles
We show that the locally constant force necessary to get a stable hyperbolic
motion regime for classical charged point particles, actually, is a combination
of an applied external force and of the electromagnetic radiation reaction
force. It implies, as the strong Equivalence Principle is valid, that the
passive gravitational mass of a charged point particle should be slight greater
than its inertial mass. An interesting new feature that emerges from the
unexpected behavior of the gravitational and inertial mass relation, for
classical charged particles, at very strong gravitational field, is the
existence of a critical, particle dependent, gravitational field value that
signs the validity domain of the strong Equivalence Principle. For electron and
proton, these critical field values are
and , respectively
Small oscillations of a chiral Gross-Neveu system
We study the small oscillations regime (RPA approximation) of the
time-dependent mean-field equations, obtained in a previous work, which
describe the time evolution of one-body dynamical variables of a uniform Chiral
Gross-Neveu system. In this approximation we obtain an analytical solution for
the time evolution of the one-body dynamical variables. The two-fermion physics
can be explored through this solution. The condition for the existence of bound
states is examined.Comment: 21pages, Latex, 1postscript figur
Initial-conditions problem for a Chiral Gross-Neveu system
A time-dependent projection technique is used to treat the initial-value
problem for self-interacting fermionic fields. On the basis of the general
dynamics of the fields, we derive formal equations of kinetic type for the set
of one-body dynamical variables. A nonperturbative mean-field expansion can be
written for these equations. We treat this expansion in lowest order, which
corresponds to the Gaussian mean-field approximation, for a uniform system
described by the Chiral Gross-Neveu Hamiltonian. Standard stationary features
of the model, such as dynamical mass generation due to chiral symmetry breaking
and a phenomenon analogous to dimensional transmutation, are reobtained in this
context. The mean-field time evolution of non-equilibrium initial states is
discussed.Comment: 31 pages, latex, 3 figures. The previous section 5 has been split
into sections 5 and