1 May 2020 to 31 January 2021
Department of Theoretical Physics, Jožef Stefan Institute
Europe/Ljubljana timezone

Crunching Dilaton, Hidden Naturalness

8 Oct 2020, 10:15
45m
https://fmf-uni-lj-si.zoom.us/j/3601731049?pwd=bVNQRjUxU2ExZ0cveWcxYXNUUGdjZz09 (Department of Theoretical Physics, Jožef Stefan Institute)

https://fmf-uni-lj-si.zoom.us/j/3601731049?pwd=bVNQRjUxU2ExZ0cveWcxYXNUUGdjZz09

Department of Theoretical Physics, Jožef Stefan Institute

Jamova 39, SI-1000 Ljubljana, Slovenija

Speaker

Dr Raffaele Tito D'Agnolo (IPHT)

Description

We introduce a new approach to the Higgs naturalness problem, where the value of the Higgs mass is tied to cosmic stability and the possibility of a large observable Universe. The Higgs mixes with the dilaton of a CFT sector whose true ground state has a large negative vacuum energy. If the Higgs VEV is non-zero and below O(TeV), the CFT also admits a second metastable vacuum, where the expansion history of the Universe is conventional. As a result, only Hubble patches with unnaturally small values of the Higgs mass support inflation and post-inflationary expansion, while all other patches rapidly crunch. The elementary Higgs VEV driving the dilaton potential is the essence of our new solution to the hierarchy problem. The main experimental prediction is a light dilaton field in the 0.1-10 GeV range that mixes with the Higgs. Part of the viable parameter space has already been probed by measurements of rare B-meson decays, and the rest will be fully explored by future colliders and experiments searching for light, weakly-coupled particles.

Presentation materials