The method of the kernel of the evolution equation in the gravity theory

TL;DR

This paper develops a covariant perturbation method to compute the kernel of evolution equations in gravity, introducing a universal scale parameter with implications for axiomatic cosmology and the action of field theories including gravity.

Contribution

It proposes an axiomatic definition of the effective action with a universal scale parameter, linking geometrical results to physical actions in gravity and cosmology.

Findings

Reproduces Einstein-Hilbert action with cosmological constant

Introduces a variable universal scale parameter

Connects the scale to the Hubble constant

Abstract

The method of 'covariant perturbation theory' allowed for the computation of the kernel of the evolution equation on a spin Riemannian manifold. The proposed axiomatic definition of the effective action introduces the universal scale parameter, with the length square dimensionality, into a dimensionless mathematical theory. It is shown that this geometrical result has a physical meaning of the action of field theory, including gravity. Two orders lowest in a tensor rank in this functional are independent of a spin group and local. They reproduce the action of relativity with the cosmological constant. The modern value of the universal scale could be determined by the measured Hubble constant. The variable scale parameter could let us build axiomatic cosmological theories.