Summary: CALT­68­1427
DOE RESEARCH AND
DEVELOPMENT REPORT
Non­Gaussian Density Perturbations in Inflationary Cosmologies #
T. J. Allen, B. Grinstein and Mark B. Wise +
California Institute of Technology, Pasadena, CA 91125
Abstract
The primordial mass density fluctuations may have arisen from quantum fluctuations in a
(massless) scalar field that occurred during an inflationary era. We show that it is possible for
primordial mass density fluctuations, which arose in this way, to be highly non­Gaussian. We
also show that the ``bad'' infrared properties of the propagator for a massless scalar field in de
Sitter space can translate itself into a power spectrum, for the the two­point spatial correlation
of objects that do not trace the mass, which behaves like k -3 , at small wave numbers k.
# Work supported in part by the U.S. Department of Energy under Contracts DEAC­03­81­ER40050 and
DE­FG03­84­ER40172.
+ Sloan Fellow.

Limits on the anisotropy of the microwave background radiation restrict the primordial fluc­
tuations in the mass density to be small at early times. However, the fluctuations do grow in the
matter­dominated era because of gravitational instability. Presumably the primordial fluctua­

Source: Allen, Theodore J. - Physics Department, Hobart and William Smith Colleges

Collections: Physics