Local Cosmology

TL;DR

This paper introduces a method to approximate complex cosmological models with simpler, maximally symmetric space-times sharing key observational parameters, aiding understanding of local-global universe interactions.

Contribution

It defines maximally symmetric osculating space-times at any event in Robertson-Walker models and applies this to approximate models and explore local-global universe influences.

Findings

Approximation of cosmological models using maximally symmetric space-times.

Insight into the influence of the universe's overall behavior on local systems.

Method for matching observational parameters at points of tangency.

Abstract

We define the concept of a Maximally symmetric osculating space-time at any event of any given Robertson-Walker model. We use this definition in two circumstances: i) to approximate any given cosmological model by a simpler one sharing the same observational parameters, i.e, the speed of light, the Hubble constant and the deceleration parameter at the time of tangency, and ii) to shed some light on the problem of considering an eventual influence of the overall behaviour of the Universe on localized systems at smaller scales, or viceversa.