The formation of compact objects at finite temperatures in a dark-matter-candidate self-gravitating bosonic system

TL;DR

This paper investigates the formation of finite-temperature compact objects in self-gravitating bosonic systems, using numerical simulations of the GPPE and SGLPE, revealing a thermally driven phase transition and binary condensate states.

Contribution

It introduces a novel numerical approach to study finite-temperature effects in self-gravitating bosonic systems and uncovers a first-order transition between condensed and gaseous states.

Findings

Identification of a thermally driven first-order transition from BEC to Bose gas.

Efficient simulation of steady states using stochastic Ginzburg-Landau-Poisson equation.

Observation of binary condensate configurations rotating around their center of mass.

Abstract

We study self-gravitating bosonic systems, candidates for dark-matter halos, by carrying out a suite of direct numerical simulations (DNSs) designed to investigate the formation of finitetemperature, compact objects in the three-dimensional (3D) Fourier-truncated Gross-Pitaevskii-Poisson equation (GPPE). This truncation allows us to explore the collapse and fluctuations of compact objects, which form at both zero temperature and finite temperature. We show that the statistically steady state of the GPPE, in the large-time limit and for the system sizes we study, can also be obtained efficiently by tuning the temperature in an auxiliary stochastic Ginzburg-Landau-Poisson equation (SGLPE). We show that, over a wide range of model parameters, this system undergoes a thermally driven first-order transition from a collapsed, compact, Bose-Einstein condensate (BEC) to a tenuous Bose gas without condensation. By a suitable choice of initial conditions in the GPPE, we also obtain a binary condensate that comprises a pair of collapsed objects rotating around their center of mass.