UCL Astrophysics Group


UCL Physicists awarded share in Buchalter Cosmology Prize

31 January 2019

UCL Physicists have won a share in the 2018 Buchalter Cosmology Prize, for developing a method which could allow the origin of our Universe to be studied using a table-top experiment.

Bubble Galaxy

The Buchalter award is presented by the American Astronomical Society. The annual prize, created by Dr. Ari Buchalter in 2014, seeks to reward new ideas or discoveries that have the potential to produce a breakthrough advance in our understanding of the origin, structure, and evolution of the universe.

The discovery was made as part of Professor Hiranya Peiris’ European Research Council project “Cosmic Dawn”, which aims to test the theory of inflation; a popular concept developed around 1980 to explain several puzzles with the Big Bang Theory. One possible implication of inflation is that our own Universe was born as one ‘bubble nucleation’ within a vast multiverse.

The team showed that there are strong parallels between this bubble nucleation phenomenon and comparable effects in Bose-Einstein condensates, which can be studied in the laboratory. Computer modelling, led by UCL postdoctoral researcher Dr Jonathan Braden, showed that future experiments using these condensates will shed light on how bubble nucleation occurs.

The bubble nucleation phenomenon suggests that other Universes within the multiverse may also have formed, like the many bubbles in boiling water. This theory is hard to test, but if at any point our “bubble Universe” collided with another, there would be evidence in the form of a shock wave across space. Professor Peiris’ team is looking for this shock wave. Exploring this phenomenon through laboratory experiments with condensates will allow the team to verify predictions around how different bubble universes form and interact with each other.

Professor Peiris said: “In this paper, we serendipitously reached an unexpected and novel result by following an exploratory line of enquiry, motivated by fundamental questions. This was made possible by the availability of the flexible funding from the EU’s excellence frameworks, in this case the European Research Council. It is very important that the UK continues to invest in “blue skies research”, because one can never predict where the next breakthrough will come from."

Lead researcher Dr Braden said: “This project touches on many fundamental issues in both quantum field theory and cosmology, and we are excited to see what future work can teach us about the origin of our Universe and the fundamental laws that govern it.”

Collaborator and UCL Professor, Andrew Pontzen said: “Bubble nucleation is one example of the strange phenomenon of quantum tunnelling. At a microscopic scale it is all around us, playing a crucial role in the chemistry and biology of everyday life. We have been working towards an improved description of the bubble nucleation that may have given rise to our entire Universe, and eventually should be able to test these ideas in the laboratory.”