UK-QFT XIV

Session

IV

26 Nov 2025, 16:10

Physics Building, C14 (University of Nottingham)

8. Vacuum decay in theories with no instanton solutions

Kinga Gawrych (Imperial College London)

26/11/2025, 16:10

Talk

In QFT, a metastable vacuum state can decay through quantum tunnelling. The calculation of the decay rate relies on instantons — non-trivial classical solutions in the Euclideanized theory, saddle points of the Euclidean action. However, sometimes theories with metastable vacua do not have any instanton solutions, thus rendering the usual method of calculating decay rates unusable. An...

18. Gravitational Waves from Confinement in SU(N) Yang-Mills Theory

Rory Phipps (University of Sussex)

26/11/2025, 16:35

Talk

The advent of gravitational wave astronomy has brought with it the potential for novel approaches to study physics beyond the Standard Model. In particular, the null searches for signatures of dark matter at direct and indirect detection experiments has left the so-called “nightmare scenario”, where the dark matter interacts with the Standard Model only through gravity, a distinct possibility....

16. EFT for strong phase transitions

Farbod Rassouli (University of Nottingham)

26/11/2025, 17:00

Talk

I present an EFT framework for strong, indeed the strongest, cosmological phase transitions this is precisely where standard high-temperature dimensional reduction fails. After reviewing high-temperature dimensional reduction for weak and intermediate transitions and pinpointing where its standard assumptions fail we construct EFTs that remain valid for very strong transitions. The approach...