Towards a gauge-polyvalent Numerical Relativity code

TL;DR

This paper introduces a new numerical relativity code demonstrating gauge versatility, capable of stable long-term black hole simulations in various coordinate systems using advanced algorithms.

Contribution

The paper presents a gauge-polyvalent numerical relativity code based on the Z4 formalism and robust finite-difference algorithms, capable of long-term black hole evolution without excision.

Findings

Successful long-term black hole evolution in normal coordinates

Effective gauge handling in harmonic and singularity-avoiding coordinates

Demonstration of code stability up to 1000M in black hole simulations

Abstract

The gauge polyvalence of a new numerical code is tested, both in harmonic-coordinate simulations (gauge-waves testbed) and in singularity-avoiding coordinates (simple Black-Hole simulations, either with or without shift). The code is built upon an adjusted first-order flux-conservative version of the Z4 formalism and a recently proposed family of robust finite-difference high-resolution algorithms. An outstanding result is the long-term evolution (up to 1000M) of a Black-Hole in normal coordinates (zero shift) without excision.