Gravitationally Bound Bose Condensates with Rotation

TL;DR

This paper develops a gravitoelectromagnetic framework for analyzing rotating, self-gravitating Bose-Einstein condensates as dark matter candidates, using variational methods to explore stability and dynamics.

Contribution

It introduces a self-consistent GEM formulation for rotating BECs with gravitational effects, including frame dragging, and analyzes stability conditions with variational techniques.

Findings

Stable rotating condensate configurations identified.

Conditions for gravitational collapse stability derived.

Approximate dynamics of imploding condensates described.

Abstract

We develop a self-consistent, Gravitoelectromagnetic (GEM) formulation of a slowly rotating, self-gravitating and dilute Bose-Einstein condensate (BEC), intended for astrophysical applications in the context of dark matter halos. GEM self-consistently incorporates the effects of frame dragging to lowest order in $v/c$ via the Gravitomagnetic field. BEC dark matter has attracted attention as an alternative to Cold dark matter (CDM) and Warm dark matter (WDM) for some time now. The BEC is described by the Gross-Pitaevskii-Poisson (GPP) equation with an arbitrary potential allowing for either attractive or repulsive interactions. Owing to the difficulty in obtaining exact solutions to the GEM equations of motion without drastic approximations, we employ the variational method to examine the conditions under which rotating condensates, stable against gravitational collapse, may form in models with attractive and repulsive quartic interactions. We also describe the approximate dynamics of an imploding and rotating condensate by employing a collective coordinate description in terms of the condensate radius.