INVESTIGADORES
CALZETTA Esteban Adolfo
artículos
Título:
Coarse-graining approach to quantum cosmology
Autor/es:
MARIO CASTAGNINO; ROMAN SCOCCIMARRO; ESTEBAN CALZETTA
Revista:
PHYSICAL REVIEW D - PARTICLE AND FILDS
Editorial:
APS
Referencias:
Año: 1992 vol. 45 p. 2806 - 2813
ISSN:
0556-2821
Resumen:
We consider a Friedmann-Robertson-Walker model with both classical
radiation and a massive (conformally coupled) quantum scalar field in
the framework of quantum cosmology. We define a density matrix and
introduce a notion of "relevance" which splits this density matrix into a
"relevant" and an "irrelevant" part. A "generalized coarse-graining
method" is used to obtain the evolution (in Robertson-Walker a
"time") of the relevant density matrix, taking into account the back
reaction of the irrelevant variables. We discuss the physical basis for
the choice of a concept of relevance, and the features of cosmic
evolution brought forward by the effective dynamics. In the limit of
"small universes," the relevant subdynamics is dissipative.