Cosmology, Particle Physics and Superfluid 3He

TL;DR

This paper explores how superfluid helium-3 can serve as a laboratory analogue for cosmological phenomena, including topological defects, baryogenesis, and early universe phase transitions, providing insights into fundamental physics.

Contribution

It demonstrates the parallels between superfluid 3He phenomena and cosmological theories, highlighting experimental methods to simulate early universe processes.

Findings

Detection of topological defects in superfluid 3He.

Simulation of defect-mediated baryogenesis.

Observation of vortex formation in neutron-irradiated 3He-B.

Abstract

Many direct parallels connect superfluid 3He with the field theories describing the physical vacuum, gauge fields and elementary fermions. Superfluid $^3$He exhibits a variety of topological defects which can be detected with single-defect sensitivity. Modern scenarios of defect-mediated baryogenesis can be simulated by the interaction of the 3He vortices and domain walls with fermionic quasiparticles. Formation of defects in a symmetry-breaking phase transition in the early Universe, which could be responsible for large-scale structure formation and for microwave-background anisotropy, also may be modelled in the laboratory. This is supported by the recent observation of vortex formation in neutron-irradiated 3He-B where the "primordial fireball" is formed in an exothermic nuclear reaction.