NRPyCritCol & SFcollapse1D: an open-source, user-friendly toolkit to study critical phenomena

Abstract

We present a new open-source, user-friendly toolkit of two codes$-$SFcollapse1D and NRPyCritCol$-$to study critical phenomena in the context of gravitational collapse. SFcollapse1D is a C/C++ tool designed to solve the problem of gravitational collapse of massless, spherically symmetric scalar fields with the ADM formalism in spherical-like coordinates. NRPyCritColis a collection of Python modules that leverage the NRPy+ infrastructure to generate a highly optimized C-code for evolving massless scalar fields within a covariant BSSN formalism. The toolkit was developed with user-friendliness and code efficiency in mind, enabling the exploration of critical phenomena with consumer-grade computers. We present a study of critical phenomena from the collapse of massless scalar fields in spherical symmetry, using only these two codes and a laptop computer.

Matches published version. 22 pages, 5 figures, 1 table. Replaced Fig. 4 with a more detailed one; extended Table I; added Refs. 7 and 16; added useful URL to Ref. 26; fixed typos