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arXiv · 2406.14718

Stirring the false vacuum via interacting quantized bubbles on a 5564-qubit quantum annealer

Abstract

False vacuum decay is a potential mechanism governing the evolution of the early Universe, with profound connections to non-equilibrium quantum physics, including quenched dynamics, the Kibble-Zurek mechanism, and dynamical metastability. The non-perturbative character of the false vacuum decay and the scarcity of its experimental probes make the effect notoriously difficult to study, with many basic open questions, such as how the bubbles of true vacuum form, move and interact with each other. Here we utilize a quantum annealer with 5564 superconducting flux qubits to directly observe quantized bubble formation in real time -- the hallmark of false vacuum decay dynamics. Moreover, we develop an effective model that describes the initial bubble creation and subsequent interaction effects. We demonstrate that the effective model remains accurate in the presence of dissipation, showing that our annealer can access coherent scaling laws in driven many-body dynamics of 5564 qubits for over $1\mu$s, i.e., more than 1000 intrinsic qubit time units. This work sets the stage for exploring late-time dynamics of the false vacuum at computationally intractable system sizes, dimensionality, and topology in quantum annealer platforms.

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Jaka Vodeb, Jean-Yves Desaules, Andrew Hallam, Andrea Rava, Gregor Humar, Dennis Willsch, Fengping Jin, Madita Willsch, Kristel Michielsen, Zlatko Papić. 2024-06-20. Stirring the false vacuum via interacting quantized bubbles on a 5564-qubit quantum annealer. https://doi.org/10.1038/s41567-024-02765-w

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