Black holes as portals to an Euclidean realm

TL;DR

This paper explores the theoretical possibility that black holes could serve as portals to a Euclidean realm, involving de Sitter cores and specific interior structures consistent with a cosmological transition.

Contribution

It proposes a novel model where black holes contain de Sitter cores acting as entry portals to a Euclidean regime, advancing understanding of cosmological boundary conditions.

Findings

Black holes may host de Sitter cores compatible with Euclidean portals

A spacelike shell of non-inflationary matter is likely necessary inside BHs

The interior structure of such black holes aligns with a one-cycle cosmological scenario

Abstract

Motivated by a one-cycle cosmological scenario where the big bang marks the egress from a Euclidean metric signature regime, we investigate the possibility of black holes (BH) hosting the mirroring entryways. Analogous to the inflationary stage following the exit end, the entry portals must be enveloped by de Sitter cores inside BHs, in order to satisfy regularity conditions at the metric signature transition boundary. We examine the interior structure of BHs that could be consistent with such a physical picture, and conclude that the presence of a spacelike shell of non-inflationary matter is likely required.