Projects per year
Abstract
Firstorder phase transitions in the very early universe are a prediction of many extensions of the Standard Model of particle physics and could provide the departure from equilibrium needed for a dynamical explanation of the baryon asymmetry of the Universe. They could also produce gravitational waves of a frequency observable by future spacebased detectors such as the Laser Interferometer Space Antenna. All calculations of the gravitational wave power spectrum rely on a relativistic version of the classical nucleation theory of CahnHilliard and Langer, due to Coleman and Linde. The high purity and precise control of pressure and temperature achievable in the laboratory made the firstorder A to B transition of superfluid ^{3}He ideal for test of classical nucleation theory. As Leggett and others have noted, the theory fails dramatically. The lifetime of the metastable A phase is measurable, typically of order minutes to hours, far faster than classical nucleation theory predicts. If the nucleation of B phase from the supercooled A phase is due to a new, rapid intrinsic mechanism that would have implications for firstorder cosmological phase transitions as well as predictions for gravitational wave production in the early universe. Here we discuss studies of the AB phase transition dynamics in ^{3}He, both experimental and theoretical, and show how the computational technology for cosmological phase transition can be used to simulate the dynamics of the AB transition, support the experimental investigations of the AB transition in the QUESTDMC collaboration with the goal of identifying and quantifying the mechanism(s) responsible for nucleation of stable phases in ultrapure metastable quantum phases.
Original language  English 

Number of pages  30 
Journal  Journal of Low Temperature Physics 
Early online date  8 Jun 2024 
DOIs  
Publication status  Epub ahead of print  8 Jun 2024 
Keywords
 helium3
 phase transitions
 timedependent GinzburgLandau equation
 cosmology
 early Universe
 gravitational waves
Projects
 1 Finished

QUESTDMC: Quantum Enhanced Superfluid Technologies for Dark Matter and Cosmology
Casey, A. (PI), Monroe, J. (CoI), West, S. (CoI), Saunders, J. (CoI) & Rojas, X. (CoI)
Science & Tech Fac Coun (STFC)
1/12/20 → 30/04/24
Project: Research