Physicists recreated the expanding universe in a cloud of freezing gas just to find a rare "quantum echo" from the void.
arXiv · March 18, 2026 · 2603.16095
The Takeaway
Using a Bose-Einstein condensate to mimic the growth of the cosmos, researchers predicted the 'temporal Efimov effect'—a phenomenon where particles pop into existence in a repeating, rhythmic pattern. This suggests the vacuum of the early universe may have had a hidden, self-repeating geometric structure as it expanded.
From the 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