BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Hofie Hassendottir (Harvard) DTSTART:20200930T183000Z DTEND:20200930T193000Z DTSTAMP:20260404T095423Z UID:UChicagoParticle/1 DESCRIPTION:Title: A Finite S-matrix\nby Hofie Hassendottir (Harvard) as part of U Chicago Particle Theory Seminars\n\nAbstract: TBA\n LOCATION:https://stable.researchseminars.org/talk/UChicagoParticle/1/ END:VEVENT BEGIN:VEVENT SUMMARY:Michael Geller (Tel Aviv) DTSTART:20201007T150000Z DTEND:20201007T160000Z DTSTAMP:20260404T095423Z UID:UChicagoParticle/2 DESCRIPTION:Title: Crunching Dilaton\, Hidden Naturalness\nby Michael Gel ler (Tel Aviv) as part of U Chicago Particle Theory Seminars\n\n\nAbstract \nWe introduce a new approach to the Higgs naturalness problem\, where the value of the Higgs mass is tied to cosmic stability and the possibility o f a large observable Universe. The Higgs mixes with the dilaton of a CFT s ector whose true ground state has a large negative vacuum energy. If the H iggs VEV is non-zero and below O(TeV)\, the CFT also admits a second metas table vacuum\, where the expansion history of the Universe is conventional . As a result\, only Hubble patches with unnaturally small values of the H iggs mass support inflation and post-inflationary expansion\, while all ot her patches rapidly crunch. The elementary Higgs VEV driving the dilaton p otential 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 ra nge that mixes with the Higgs. Part of the viable parameter space has alre ady 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.\n LOCATION:https://stable.researchseminars.org/talk/UChicagoParticle/2/ END:VEVENT BEGIN:VEVENT SUMMARY:Clifford Johnson (USC) DTSTART:20201014T183000Z DTEND:20201014T193000Z DTSTAMP:20260404T095423Z UID:UChicagoParticle/3 DESCRIPTION:Title: Non-perturbative studies of JT gravity and supergravity\nby Clifford Johnson (USC) as part of U Chicago Particle Theory Seminars \n\n\nAbstract\nJackiw–Teitelboim (JT) gravity and supergravity theories are exciting solvable models that teach us about low temperature black ho le dynamics\, and aspects of quantum chaotic behaviour. They have been sho wn (by Saad\, Shenker and Stanford\, and by Stanford and Witten) to have d ouble scaled random matrix model descriptions\, capturing the (spacetime) topological perturbative expansion of the partition function. I will descr ibe an alternative method for building the matrix model description\, usin g techniques from minimal string theory. This method is particularly usefu l for supplying non-perturbative definitions of the physics. I show how th is allows for the computation of key aspects of \nthe physics at low energ y and temperature.\n LOCATION:https://stable.researchseminars.org/talk/UChicagoParticle/3/ END:VEVENT BEGIN:VEVENT SUMMARY:Timothy Cohen (University of Oregon) DTSTART:20201022T183000Z DTEND:20201022T193000Z DTSTAMP:20260404T095423Z UID:UChicagoParticle/4 DESCRIPTION:Title: Soft de Sitter Effective Theory\nby Timothy Cohen (Uni versity of Oregon) as part of U Chicago Particle Theory Seminars\n\n\nAbst ract\nIn this talk\, I will introduce the Soft de Sitter Effective Theory (SdSET)\, whose purpose is to model the long wavelength dynamics of quantu m fluctuations beyond the horizon. After providing some conceptual and te chnical issues that motivate the need for a new EFT approach\, I will expl ain how we identify the propagating low energy degrees of freedom\, along with their scaling under a power counting scheme and their transformation properties under the symmetries that persist to the IR. I will sketch how to derive the\nSdSET action\, and will argue that it can be expressed as an expansion in local operators\, augmented by stochastic initial conditio ns. Finally\, I will show how this framework can be applied to a number o f physically interesting problems: massive scalar fields in dS\, light sca lar fields and stochastic inflation\, conservation of the inflationary\nad iabatic modes\, and the phase transition to eternal inflation.\n LOCATION:https://stable.researchseminars.org/talk/UChicagoParticle/4/ END:VEVENT BEGIN:VEVENT SUMMARY:Costis Papageorgakis (Queen Mary University of London) DTSTART:20201028T150500Z DTEND:20201028T160500Z DTSTAMP:20260404T095423Z UID:UChicagoParticle/5 DESCRIPTION:Title: Type-B Anomalies on the Higgs Branch\nby Costis Papage orgakis (Queen Mary University of London) as part of U Chicago Particle Th eory Seminars\n\nAbstract: TBA\n LOCATION:https://stable.researchseminars.org/talk/UChicagoParticle/5/ END:VEVENT BEGIN:VEVENT SUMMARY:Andreas Crivellin (University of Zurich) DTSTART:20201118T193000Z DTEND:20201118T203000Z DTSTAMP:20260404T095423Z UID:UChicagoParticle/6 DESCRIPTION:Title: Discovering New Physics with Flavour\nby Andreas Crive llin (University of Zurich) as part of U Chicago Particle Theory Seminars\ n\n\nAbstract\nDiscovering New Physics with Flavour Within recent year\, f lavour and low-energy precision experiments have accumulated intriguing hi nts for the violation of lepton flavour universality (LFU)\, i.e. physics beyond the Standard Model which interacts differently with electrons\, muo ns and tau leptons. In particular\, the long-standing anomaly in the anoma lous magnetic moment (AMM) of the muon is now accompanied tensions in semi -leptonic B decays (most pronounced in b->smumu data) as well as its sibli ng\, the AMM of the electron. Furthermore\, also the hint for a (apparent) violation of first-row CKM unitarity can be viewed as a sign for LFU viol ation. \nAfter reviewing the current experimental and theoretical status\, I discuss how these anomalies can be (individually) explained in terms of NP. Furthermore\, combining the explanations of different anomalies\, one can predict interesting correlations with\, and signatures in\, other fla vour observables. Furthermore\, the flavour anomalies can be used to const ruct a compelling physics case for future colliders such as the FCC-ee and the FCC-hh.\n LOCATION:https://stable.researchseminars.org/talk/UChicagoParticle/6/ END:VEVENT BEGIN:VEVENT SUMMARY:Benedict von Harling (IFAE Barcelona) DTSTART:20210331T183000Z DTEND:20210331T193000Z DTSTAMP:20260404T095423Z UID:UChicagoParticle/7 DESCRIPTION:Title: Baryogenesis via gauge field production from a relaxing Hi ggs\nby Benedict von Harling (IFAE Barcelona) as part of U Chicago Par ticle Theory Seminars\n\n\nAbstract\nIn this talk\, I will discuss how the baryon asymmetry of the universe can be explained in models where the Hig gs couples to the Chern-Simons term of the hypercharge group and is away f rom the late-time minimum of its potential during inflation. The Higgs the n relaxes toward this minimum once inflation ends which leads to the produ ction of (hyper)magnetic helicity. I will discuss conditions under which t his helicity can be approximately conserved during its joint evolution wit h the thermal plasma. At the electroweak phase transition the helicity is then converted into a baryon asymmetry by virtue of the chiral anomaly in the standard model. I will present a simple model which realizes this mech anism and show that the observed baryon asymmetry of the universe can be r eproduced.\n LOCATION:https://stable.researchseminars.org/talk/UChicagoParticle/7/ END:VEVENT BEGIN:VEVENT SUMMARY:Matthew McCullough (CERN & Cambridge) DTSTART:20210623T183000Z DTEND:20210623T193000Z DTSTAMP:20260404T095423Z UID:UChicagoParticle/8 DESCRIPTION:Title: Self-Organised Localisation\nby Matthew McCullough (CE RN & Cambridge) as part of U Chicago Particle Theory Seminars\n\n\nAbstrac t\nWe describe a new phenomenon in quantum cosmology: self-organised local isation. When the fundamental parameters of a theory are functions of a sc alar field subject to large fluctuations during inflation\, quantum phase transitions can act as dynamical attractors. As a result\, the theory para meters are probabilistically localised around the critical value and the U niverse finds itself at the edge of a phase transition. We illustrate how self-organised localisation could account for the observed near-criticalit y of the Higgs self-coupling\, the naturalness of the Higgs mass\, or the smallness of the cosmological constant.\n LOCATION:https://stable.researchseminars.org/talk/UChicagoParticle/8/ END:VEVENT END:VCALENDAR