# Hot News on the phase structure of the SMEFT

- Institution: CERN
- Speaker: Maria Cristina Fiore
- Year: 2026
- Language: English
- Source: [CERN](https://videos.cern.ch/record/3020962)
- Licence: [CERN](https://copyright.web.cern)
- Who can watch: Teens profiles and older (sources give no ratings; placed by Invisible Network from the source's own words)

We study the high-temperature behavior of the electroweak sector of the Standard Model Effective Field Theory (SMEFT), including dimension-six operators, by performing dimensional reduction up to $\mathcal{O}(g^4)$ in the gauge couplings. Our derivation accounts for one-loop corrections to kinetic terms and scalar quartic couplings, as well as two-loop contributions to thermal mass parameters. The latter include effects from purely bosonic operators and from four-fermion interactions. The resulting three-dimensional theory provides a suitable framework for non-perturbative investigations of the thermal history of the early universe within the SMEFT. In particular, we discuss how existing lattice results can be employed to assess the viability of a phase transition in this extended setup, even in the absence of modifications to the vacuum structure at zero temperature.

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## Lectures

1. [Hot News on the phase structure of the SMEFT](https://invisiblenetwork.ai/learn/cern/3020962/1ea3e838c6f7), 9 min (CERN's player)