A discrete nonetheless remarkable brick in de Sitter: the "massless minimally coupled field"

TL;DR

This paper reviews the covariant quantization of the massless minimally coupled field in de Sitter space and discusses its importance in inflation models and constructing a massless spin 2 field.

Contribution

It provides a comprehensive review of the Krein-Gupta-Bleuler quantization method for the mmc field in de Sitter space and highlights its significance in gravitational field construction.

Findings

Clarifies the role of the mmc field in inflationary cosmology

Details the Krein-Gupta-Bleuler quantization approach

Connects the mmc field to massless spin 2 field construction

Abstract

Over the last ten years interest in the physics of de Sitter spacetime has been growing very fast. Besides the supposed existence of a "de sitterian period" in inflation theories, the observational evidence of an acceleration of the universe expansion (interpreted as a positive cosmological constant or a "dark energy" or some form of "quintessence") has triggered a lot of attention in the physics community. A specific de sitterian field called "massless minimally coupled field" (mmc) plays a fundamental role in inflation models and in the construction of the de sitterian gravitational field. A covariant quantization of the mmc field, `a la Krein-Gupta-Bleuler was proposed in [1]. In this talk, we will review this construction and explain the relevance of such a field in the construction of a massless spin 2 field in de Sitter space-time.