This paper is available on arxiv under CC 4.0 license.
Authors:
(1) Igor Yu. Potemine, Institut de Math´ematiques, Universit´e Paul Sabatier.
It turns out that nested Gogberashvili shells represent good models for multiverses inside the Hyperverse.
In this paper we have restrained the Hyperverse to its local (4 + 1)- dimensional stratum. However, similar solutions exist in all dimensions d + 1 with d > 2. In fact, we can construct an infinite tower of embedded Gogberashvili multiverses of various dimensions.
An alternative approach is given by Robinson-Trautman metrics describing expanding spacetimes and spherical gravitational waves. It provides us with an intriguing idea to consider supermassive astronomical black holes as expanding (2 + 1)-dimensional multiverses (with possible higher strata too).
It might give new angles of view on the black hole growth, the cosmological coupling, relativistic jets and even on the classification of galaxies.
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