Origin of Structure in the Universe: Quantum Cosmology Reconsidered

TL;DR

This paper proposes a new reduced quantization approach for slightly inhomogeneous cosmology, emphasizing geometric analysis of configuration spaces, offering a potentially clearer framework than traditional Dirac quantization.

Contribution

It introduces a superspace-based reduced quantization method for inhomogeneous cosmology, improving upon the Dirac approach by analyzing configuration space geometries.

Findings

Reduced quantization is achieved in vacuum cosmology.

Some configuration spaces are identified as flat, simplifying analysis.

Coordinates are interpreted through mode expansion coefficients.

Abstract

Based on a more careful canonical analysis, we motivate a reduced quantization - in the sense of superspace quantization - of slightly inhomogeneous cosmology in place of the Dirac quantization in the existing literature, and provide it in the vacuum case. This is attained through consideration of configuration space geometries at various levels of reduction. Some of these have the good fortunate of being flat. Geometrically natural coordinates for these are interpreted in terms of the original redundant formulation's well-known mode expansion coefficients.