Optical analogues of the Newton-Schr\"odinger equation and boson star evolution

TL;DR

This paper demonstrates an optical system that replicates the Newton-Schrodinger equation, allowing experimental study of boson star dynamics and instabilities in a controlled laboratory setting.

Contribution

It introduces a novel optical analogue of the Newton-Schrodinger equation to model boson star evolution experimentally and numerically.

Findings

Optical system successfully models boson star oscillations and stability.

High-density instabilities cause apparent breakup but maintain coherence.

Optical analogues provide new insights into gravitational phenomena.

Abstract

Many gravitational phenomena that lie at the core of our understanding of the Universe have not yet been directly observed. An example in this sense is the boson star that has been proposed as an alternative to some compact objects currently interpreted as being black holes. In the weak field limit, these stars are governed by the Newton-Schrodinger equation (NSE). Here we present an optical system that, under appropriate conditions, identically reproduces the NSE in two dimensions. A rotating boson star is experimentally and numerically modelled by an optical beam propagating through a medium with a positive thermal nonlinearity and is shown to oscillate in time while also stable up to relatively high densities. For higher densities, instabilities lead to an apparent breakup of the star, yet coherence across the whole structure is maintained. These results show that optical analogues can be used to shed new light on inaccessible gravitational objects.