Quantum fluctuations, decoherence of the mean field, and structure formation in the early universe

ESTEBAN CALZETTA; BEI-LOK HU

PHYSICAL REVIEW D - PARTICLE AND FILDS

APS

Lugar: Ridge; Año: 1995 vol. 52 p. 6770 - 6788

0556-2821

We examine from first principles one of the basic assumptions of modern quantum theories of structure formation in the early universe, i.e., the conditions upon which fluctuations of a quantum field may transmute into classical stochastic perturbations, which grew into galaxies. Our earlier works have discussed the quantum origin of noise in stochastic inflation and quantum fluctuations as measured by particle creation in semiclassical gravity. Here we focus on decoherence and the relation of quantum and classical fluctuations.