Cosmological Term and Fundamental Physics

TL;DR

This paper explores how a nonzero cosmological term modifies spacetime symmetries, impacting fundamental physics concepts and potentially altering early universe models and matter equations of state.

Contribution

It provides a qualitative analysis of the profound effects of the cosmological term on spacetime symmetries and fundamental physics in cosmology.

Findings

Spacetime translations shift from Poincare' to de Sitter group.

Alterations in concepts of time, energy, and momentum.

Potential significant effects on early universe physics.

Abstract

A nonvanishing cosmological term in Einstein's equations implies a nonvanishing spacetime curvature even in absence of any kind of matter. It would, in consequence, affect many of the underlying kinematic tenets of physical theory. The usual commutative spacetime translations of the Poincare' group would be replaced by the mixed conformal translations of the de Sitter group, leading to obvious alterations in elementary concepts such as time, energy and momentum. Although negligible at small scales, such modifications may come to have important consequences both in the large and for the inflationary picture of the early Universe. A qualitative discussion is presented which suggests deep changes in Hamiltonian, Quantum and Statistical Mechanics. In the primeval universe as described by the standard cosmological model, in particular, the equations of state of the matter sources could be quite different from those usually introduced.