Penrose Diagram for a Transient Black Hole

TL;DR

This paper constructs a Penrose diagram for a transient black hole that forms and dissolves symmetrically, showing that its life cycle leaves asymptotic observers in an unaltered Minkowski space-time.

Contribution

It provides a detailed Penrose diagram for a black hole with a smooth, symmetric life cycle, including computational derivation of coordinate curves.

Findings

Black hole forms and dissolves symmetrically in the diagram

Causal relationships between space-time regions are analyzed

Observers at infinity see no change in the overall space-time structure

Abstract

A Penrose diagram is constructed for a spatially coherent black hole that smoothly begins an accretion, then excretes symmetrically as measured by a distant observer, with the initial and final states described by a metric of Minkowski form. Coordinate curves on the diagram are computationally derived. Causal relationships between space-time regions are briefly discussed. The life cycle of the black hole demonstrably leaves asymptotic observers in an unaltered Minkowski space-time of uniform conformal scale.