Signature-Change Events, Trans-Planckian Physics and Quasi-Particle Amplification in Bose-Einstein Condensates

Abstract

We explore signature-changing emergent geometries in a BEC; specifically analogues of signature change from Euclidean to Lorentzian regions. In our BEC-based analogue model, signature change is achieved via a change in atomic interactions from repulsive to attractive. The particle production resulting from a finite-duration Euclidean-signature event is calculated firstly in the hydrodynamic limit. A combination of trans-Planckian physics and signature change results from the inclusion of ultraviolet modes, modifying the expected particle production. We also propose using analogue signature changing events as an amplifier for analogue ``cosmological particle production” and investigate the experimental applicability of this in future BEC experiments. Article not available.