Local regions with expanding extra dimensions

TL;DR

This paper explores the theoretical possibility of spatial regions with expanding extra dimensions within $f(R)$ gravity, suggesting they could form during inflation due to quantum fluctuations and exhibit specific curvature and size behaviors.

Contribution

It introduces a model for regions with expanding extra dimensions in $f(R)$ gravity, highlighting their formation mechanism and internal properties.

Findings

Regions with expanding extra dimensions can form during inflation.

Their interior curvature tends to zero over time.

The size of extra dimensions grows slowly during evolution.

Abstract

We study possible spatial domains containing expanding extra dimensions. We show that they are predicted in the framework of $f(R)$ gravity and could appear due to quantum fluctuations during inflation. Their interior is characterized by the multidimensional curvature ultimately tending to zero and a slowly growing size of the extra dimensions.