Efimovian Phonon Production for an Analog Coasting Universe in Bose-Einstein Condensates

TL;DR

This paper predicts a temporal Efimov effect in a Bose-Einstein condensate simulating an expanding universe, leading to distinctive phonon production patterns that can be experimentally observed.

Contribution

It introduces the concept of a temporal Efimov effect in an analog cosmological setting using Bose-Einstein condensates, bridging Efimov physics and cosmology.

Findings

Prediction of power-law growth in phonon particle production.

Identification of log-periodic oscillations as Efimov signatures.

Mapping of phonon dynamics to cosmological modes.

Abstract

Efimov effects arise from scale invariance, a fundamental symmetry with universal implications. While spatial Efimov physics has been extensively studied, realizing its temporal counterpart remains challenging, as it requires a dynamical system that breaks time-translation symmetry yet preserves the essential time-scaling symmetry. Analog cosmology offers a powerful platform to address this challenge, bridging the domains of Efimov physics and cosmology. Here, we predict a temporal Efimov effect in an analog linearly expanding universe realized with a quasi-two-dimensional Bose-Einstein condensate. The invariance of phonon mode equations under time rescaling leads to particle production with two distinct dynamics: power-law growth and log-periodic oscillations, with the latter being the hallmark signature of the Efimov effect. Furthermore, these dynamics map directly onto sub- and super-horizon cosmological modes. Our predictions can be directly verified through time-averaged measurements of the density-fluctuation spectrum $S_{k}(t)$ in current experiments.