Relativistic Thermodynamics
Relativistic Thermodynamics attempts to describe physical
processes taking into account their macroscopic variables and energy disspation
as well. In the relativistic representation of such macroscopic physical
systems one has two types of variables: universal (T((), describing energy
density and momentum, and specific, that define the components of the system.
The dynamics of specific variables and of diverse flows (besides energy
and momentum flows) is governed by the
phenomenological equations of Causal Relativistic Thermodynamics.
The present research program has two main branches. The first aims at the
derivation of the relativistic equations of a simple fluid, submitted to
dissipative processes, and is based upon Landau?s formulation - which is
still scarcely known in the literature. The process of expansion (or contraction)
of homogeneous and isotropic cosmological models (Friedman-Robertson-Walker
model) as a far-from-equilibrium process was studied next. In particular,
the efficiency of dissipation as a mechanism useful to avoid the occurrence
of the typical singularity of Friedmann-Robertson-Walker metrics was examined.
Subsequently, it is intended to enlarge the existing formalism in order
to include many-compnents fluids and fluids endowed with internal structure
(spin). In this last case, consequences of the coupling of spin to the
gravitational field were already obtained, as well as some applications
to Cosmology and conformally flat metrics. The second branch of research,
derived from the first one, envisages a systematic study of relativistic
systems (with ponderable matter) interacting with the electromagnetic field.
The modifications induced in the theory when the magnetic field is coupled
directly to the space-time curvature will be studied next. Finally, as
a consequence of this research program, macroscopic system interacting
with gravity will be investigated, so as to understand the nature of the
influence of the gravitational filed upon the thermodynamical properties
of such systems. This study also includes the analysis and calculation
of fluctuations and stability problems of cosmological models.