Black hole excision with matching

TL;DR

This paper introduces a novel method for handling black hole interiors by matching Cauchy evolution to characteristic evolution, demonstrating its effectiveness through a spherically symmetric scalar field collapse simulation.

Contribution

The paper proposes a new matching scheme for black hole excision that combines Cauchy and characteristic evolutions, offering an alternative to traditional methods.

Findings

Matching performs at least as well as other boundary handling approaches.

Prototype code demonstrates the scheme's viability in spherical symmetry.

Advantages and disadvantages of the matching scheme are discussed.

Abstract

We present a new method for treating the inner Cauchy boundary of a black hole spacetime by matching to a characteristic evolution. We discuss the advantages and disadvantages of such a scheme relative to Cauchy-only approaches. A prototype code, for the spherically symmetric collapse of a self-gravitating scalar field, shows that matching performs at least as well as other approaches to handling the inner boundary.