From the elasticity theory to cosmology and vice versa

TL;DR

This paper extends elasticity theory into four-dimensional space-time to model the universe's accelerated expansion, offering a novel interpretation of dark energy and bridging concepts between cosmology and classical elasticity.

Contribution

It introduces a generalized elasticity framework in four dimensions that integrates with general relativity, providing new insights into cosmic acceleration and dark energy.

Findings

The additional elasticity term accounts for universe's accelerated expansion.

Elasticity concepts inspire new cosmological modeling approaches.

Methods from general relativity can be applied to classical elasticity problems.

Abstract

The paper shows how a generalization of the elasticity theory to four dimensions and to space-time allows for a consistent description of the homogeneous and isotropic universe, including the accelerated expansion. The analogy is manifested by the inclusion in the traditional Lagrangian of general relativity of an additional term accounting for the strain induced in the manifold (i.e. in space-time) by the curvature, be it induced by the presence of a texture defect or by a matter/energy distribution. The additional term is sufficient to account for various observed features of the universe and to give a simple interpretation for the so called dark energy. Then, we show how the same approach can be adopted back in three dimensions to obtain the equilibrium configuration of a given solid subject to strain induced by defects or applied forces. Finally, it is shown how concepts coming from the familiar elasticity theory can inspire new approaches to cosmology and in return how methods appropriated to General Relativity can be applied back to classical problems of elastic deformations in three dimensions.