16–20 Mar 2026
CERN
Europe/Zurich timezone
There is a live webcast for this event.

Construction and limitations of EFTs for hot QFT

20 Mar 2026, 09:00
45m
4/3-006 - TH Conference Room (CERN)

4/3-006 - TH Conference Room

CERN

110
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Speaker

Philipp Schicho (University of Geneva)

Description

Finite-temperature effective field theories (EFTs) were originally developed to study thermodynamics and phase transitions in non-Abelian gauge theories. More recently, they have experienced renewed interest as a tool for determining soft contributions to real-time lightcone observables.

In the context of cosmological phase transitions, the construction of such EFTs has reached new levels of automation. In particular, full dimension-six thermal hot EFTs have recently been constructed, including hot SMEFT. In this talk, I will discuss recent progress in building these EFTs, as well as their limitations. I will also briefly highlight alternative techniques, including the heat-kernel and Hilbert-series approaches at finite temperature.

Finally, I will discuss applications of these EFTs to cosmological phase transitions and outline both old and new strategies to systematically extend perturbative control beyond the high-temperature regime, enabling reliable descriptions across a wider range of temperatures.

Presentation materials