A symmetry for vanishing cosmological constant: Another realization

TL;DR

This paper proposes a new realization of a symmetry that addresses the cosmological constant problem by forbidding it through metric transformation and spacetime reflections, suggesting a specific dimensional structure and connections to E-parity.

Contribution

It introduces a novel symmetry realization that prevents a cosmological constant and specifies the dimensionality of spacetime without extensions, linking to spacetime reflections and E-parity.

Findings

The symmetry forbids a bulk cosmological constant.

It selects 2(2n+1)-dimensional spaces for the universe.

The symmetry can be realized through spacetime reflections.

Abstract

A more conventional realization of a symmetry which had been proposed towards the solution of cosmological constant problem is considered. In this study the multiplication of the coordinates by the imaginary number $i$ in the literature is replaced by the multiplication of the metric tensor by minus one. This realization of the symmetry as well forbids a bulk cosmological constant and selects out $2(2n+1)$ dimensional spaces. On contrary to its previous realization the symmetry, without any need for its extension, also forbids a possible cosmological constant term which may arise from the extra dimensional curvature scalar provided that the space is taken as the union of two $2(2n+1)$ dimensional spaces where the usual 4-dimensional space lies at the intersection of these spaces. It is shown that this symmetry may be realized through spacetime reflections that change the sign of the volume element. A possible relation of this symmetry to the E-parity symmetry of Linde is also pointed out.