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:20260422T212748Z 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://researchseminars.org/talk/UChicagoParticle/1/ END:VEVENT BEGIN:VEVENT SUMMARY:Michael Geller (Tel Aviv) DTSTART:20201007T150000Z DTEND:20201007T160000Z DTSTAMP:20260422T212748Z UID:UChicagoParticle/2 DESCRIPTION:Title: Crunching Dilaton\, Hidden Naturalness\nby Michael Geller (Te l Aviv) as part of U Chicago Particle Theory Seminars\n\n\nAbstract\nWe in troduce 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 lar ge observable Universe. The Higgs mixes with the dilaton of a CFT sector w hose true ground state has a large negative vacuum energy. If the Higgs VE V is non-zero and below O(TeV)\, the CFT also admits a second metastable v acuum\, where the expansion history of the Universe is conventional. As a result\, only Hubble patches with unnaturally small values of the Higgs ma ss support inflation and post-inflationary expansion\, while all other pat ches rapidly crunch. The elementary Higgs VEV driving the dilaton potentia l is the essence of our new solution to the hierarchy problem. The main ex perimental prediction is a light dilaton field in the 0.1-10 GeV range tha t mixes with the Higgs. Part of the viable parameter space has already bee n probed by measurements of rare B-meson decays\, and the rest will be ful ly explored by future colliders and experiments searching for light\, weak ly-coupled particles.\n LOCATION:https://researchseminars.org/talk/UChicagoParticle/2/ END:VEVENT BEGIN:VEVENT SUMMARY:Clifford Johnson (USC) DTSTART:20201014T183000Z DTEND:20201014T193000Z DTSTAMP:20260422T212748Z UID:UChicagoParticle/3 DESCRIPTION:Title: Non-perturbative studies of JT gravity and supergravity\nby C lifford Johnson (USC) as part of U Chicago Particle Theory Seminars\n\n\nA bstract\nJackiw–Teitelboim (JT) gravity and supergravity theories are ex citing solvable models that teach us about low temperature black hole dyna mics\, and aspects of quantum chaotic behaviour. They have been shown (by Saad\, Shenker and Stanford\, and by Stanford and Witten) to have double s caled random matrix model descriptions\, capturing the (spacetime) topolog ical perturbative expansion of the partition function. I will describe an alternative method for building the matrix model description\, using techn iques from minimal string theory. This method is particularly useful for s upplying non-perturbative definitions of the physics. I show how this allo ws for the computation of key aspects of \nthe physics at low energy and t emperature.\n LOCATION:https://researchseminars.org/talk/UChicagoParticle/3/ END:VEVENT BEGIN:VEVENT SUMMARY:Timothy Cohen (University of Oregon) DTSTART:20201022T183000Z DTEND:20201022T193000Z DTSTAMP:20260422T212748Z UID:UChicagoParticle/4 DESCRIPTION:Title: Soft de Sitter Effective Theory\nby Timothy Cohen (University of Oregon) as part of U Chicago Particle Theory Seminars\n\n\nAbstract\nI n this talk\, I will introduce the Soft de Sitter Effective Theory (SdSET) \, whose purpose is to model the long wavelength dynamics of quantum fluct uations beyond the horizon. After providing some conceptual and technical issues that motivate the need for a new EFT approach\, I will explain how we identify the propagating low energy degrees of freedom\, along with th eir scaling under a power counting scheme and their transformation propert ies under the symmetries that persist to the IR. I will sketch how to der ive the\nSdSET action\, and will argue that it can be expressed as an expa nsion in local operators\, augmented by stochastic initial conditions. Fi nally\, I will show how this framework can be applied to a number of physi cally interesting problems: massive scalar fields in dS\, light scalar fie lds and stochastic inflation\, conservation of the inflationary\nadiabatic modes\, and the phase transition to eternal inflation.\n LOCATION:https://researchseminars.org/talk/UChicagoParticle/4/ END:VEVENT BEGIN:VEVENT SUMMARY:Costis Papageorgakis (Queen Mary University of London) DTSTART:20201028T150500Z DTEND:20201028T160500Z DTSTAMP:20260422T212748Z UID:UChicagoParticle/5 DESCRIPTION:Title: Type-B Anomalies on the Higgs Branch\nby Costis Papageorgakis (Queen Mary University of London) as part of U Chicago Particle Theory Se minars\n\nAbstract: TBA\n LOCATION:https://researchseminars.org/talk/UChicagoParticle/5/ END:VEVENT BEGIN:VEVENT SUMMARY:Andreas Crivellin (University of Zurich) DTSTART:20201118T193000Z DTEND:20201118T203000Z DTSTAMP:20260422T212748Z UID:UChicagoParticle/6 DESCRIPTION:Title: Discovering New Physics with Flavour\nby Andreas Crivellin (U niversity of Zurich) as part of U Chicago Particle Theory Seminars\n\n\nAb stract\nDiscovering New Physics with Flavour Within recent year\, flavour and low-energy precision experiments have accumulated intriguing hints for the violation of lepton flavour universality (LFU)\, i.e. physics beyond the Standard Model which interacts differently with electrons\, muons and tau leptons. In particular\, the long-standing anomaly in the anomalous ma gnetic moment (AMM) of the muon is now accompanied tensions in semi-lepton ic B decays (most pronounced in b->smumu data) as well as its sibling\, th e AMM of the electron. Furthermore\, also the hint for a (apparent) violat ion of first-row CKM unitarity can be viewed as a sign for LFU violation. \nAfter reviewing the current experimental and theoretical status\, I disc uss how these anomalies can be (individually) explained in terms of NP. Fu rthermore\, combining the explanations of different anomalies\, one can pr edict interesting correlations with\, and signatures in\, other flavour ob servables. Furthermore\, the flavour anomalies can be used to construct a compelling physics case for future colliders such as the FCC-ee and the FC C-hh.\n LOCATION:https://researchseminars.org/talk/UChicagoParticle/6/ END:VEVENT BEGIN:VEVENT SUMMARY:Benedict von Harling (IFAE Barcelona) DTSTART:20210331T183000Z DTEND:20210331T193000Z DTSTAMP:20260422T212748Z UID:UChicagoParticle/7 DESCRIPTION:Title: Baryogenesis via gauge field production from a relaxing Higgs \nby Benedict von Harling (IFAE Barcelona) as part of U Chicago Particle T heory Seminars\n\n\nAbstract\nIn this talk\, I will discuss how the baryon asymmetry of the universe can be explained in models where the Higgs coup les to the Chern-Simons term of the hypercharge group and is away from the late-time minimum of its potential during inflation. The Higgs then relax es toward this minimum once inflation ends which leads to the production o f (hyper)magnetic helicity. I will discuss conditions under which this hel icity can be approximately conserved during its joint evolution with the t hermal plasma. At the electroweak phase transition the helicity is then co nverted into a baryon asymmetry by virtue of the chiral anomaly in the sta ndard model. I will present a simple model which realizes this mechanism a nd show that the observed baryon asymmetry of the universe can be reproduc ed.\n LOCATION:https://researchseminars.org/talk/UChicagoParticle/7/ END:VEVENT BEGIN:VEVENT SUMMARY:Matthew McCullough (CERN & Cambridge) DTSTART:20210623T183000Z DTEND:20210623T193000Z DTSTAMP:20260422T212748Z UID:UChicagoParticle/8 DESCRIPTION:Title: Self-Organised Localisation\nby Matthew McCullough (CERN & Ca mbridge) as part of U Chicago Particle Theory Seminars\n\n\nAbstract\nWe d escribe a new phenomenon in quantum cosmology: self-organised localisation . When the fundamental parameters of a theory are functions of a scalar fi eld subject to large fluctuations during inflation\, quantum phase transit ions can act as dynamical attractors. As a result\, the theory parameters are probabilistically localised around the critical value and the Universe finds itself at the edge of a phase transition. We illustrate how self-or ganised localisation could account for the observed near-criticality of th e Higgs self-coupling\, the naturalness of the Higgs mass\, or the smallne ss of the cosmological constant.\n LOCATION:https://researchseminars.org/talk/UChicagoParticle/8/ END:VEVENT END:VCALENDAR