An experiment in Italy, supported by theoretical support from the University of Newcastle, has provided the first experimental evidence of vacuum decay.

In quantum field theory, the transformation of a not-so-stable state into a truly stable state is called “pseudovacuum decay.” This occurs due to the formation of small localized bubbles. Although existing theoretical studies can predict how often bubbles form, there is not much experimental validation.

Now, an international research team, including scientists at the University of Newcastle, has observed for the first time how these bubbles form in carefully controlled systems of atoms. The results were published in the journal Natural Physics is experimental evidence of the formation of bubbles due to faulty decay of vacuum in a quantum system.

Experimental methodology and results

The results are validated by both theoretical modeling and numerical models, confirming the quantum field origin and thermal activation of the decay and leading to the imitation of non-equilibrium quantum field phenomena in atomic systems.

The experiment uses supercooled gas whose temperature is less than one microkelvin (one-millionth of a degree) below absolute zero. At this temperature, bubbles appear to appear when the vacuum is broken, and Newcastle University Professor Ian Moss and Dr. Tom Billam, they were able to show conclusively that these bubbles were the result of thermally activated vacuum breakdown.

Implications for theoretical physics and future research

Ian Moss, professor of theoretical cosmology at Newcastle University’s School of Mathematics, Statistics and Physics, said: “Vacuum decay is thought to have played a central role in the creation of space, time and matter during the Big Bang, but until now there has been no experimental testing of the particle.” In physics, the decay of the Higgs boson in a vacuum would change the laws of physics and cause what has been described as the “ultimate environmental disaster”.

Senior lecturer in applied mathematics/quantum theory Dr. Tom Billam added: “Using the power of ultracold atom experiments to model quantum physics analogs in other systems – in this case the early universe – is a very exciting area of ​​research.” right now.”

The research opens new ways to understand the early universe and ferromagnetic quantum phase transitions.

This groundbreaking experiment is only the first step in investigating gap decay. The ultimate goal is to detect vacuum decay at absolute zero temperature, where the process is driven solely by quantum fluctuations of the vacuum. An experiment in Cambridge, supported by Newcastle as part of the national QSimFP collaboration, aims to do just that.