BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Aaron Vincent (Queen's University\, Arthur McDonald Astroparticle Institute) DTSTART:20200604T190000Z DTEND:20200604T200000Z DTSTAMP:20260422T225930Z UID:WITP-seminar/1 DESCRIPTION:Title: Very small black holes at very large experiments\nby Aaron Vincen t (Queen's University\, Arthur McDonald Astroparticle Institute) as part o f Winnipeg Institute for Theoretical Physics Seminar\n\n\nAbstract\nThe ex istence of Large Extra Dimensions has been an intriguing prospect since th ey were first suggested. In such scenarios\, the “true” Planck mass ca n be as low as a few TeV\, and much of the large discrepancy between the o bserved Planck scale and the electroweak scale can be explained by geometr ic effects. One of the more tantalizing signatures of such scenarios is th e creation of microscopic black holes in collisions of high-energy particl es. I will first describe the reach of the next generation of neutrino obs ervatories\, which can probe energies far in excess of the LHC\, and will describe the novel experimental signatures of microscopic black holes in n eutrino telescopes like IceCube Gen2. I will end by showing that\, if LEDs can be also probed at future colliders such as the FCC\, these black hole s can be used to detect and constrain dark matter — or any dark sector p article lighter than a few TeV — regardless of its coupling to the stand ard model.\n LOCATION:https://researchseminars.org/talk/WITP-seminar/1/ END:VEVENT BEGIN:VEVENT SUMMARY:Cristina Bena (Universite Paris-Saclay\, IPhT) DTSTART:20200707T150000Z DTEND:20200707T160000Z DTSTAMP:20260422T225930Z UID:WITP-seminar/2 DESCRIPTION:Title: Majorana and other boundary modes from impurity states via T-matrix\nby Cristina Bena (Universite Paris-Saclay\, IPhT) as part of Winnipeg Institute for Theoretical Physics Seminar\n\n\nAbstract\nWe provide a new and exact formalism to describe the formation of end\, edge or surface sta tes through the evolution of impurity-induced states. We propose a general algorithm that consists of finding the impurity states via the T-matrix f ormalism and showing that they evolve into boundary modes when the impurit y potential goes to infinity. We apply this technique to obtain Majorana s tates\, topological insulator edges states and graphene edges states. We a lso show that this approach provides us with a new direct and non-numerica l technique to obtain the surface Green's functions for three-dimensional systems and we apply it to Weyl semimetals.\n LOCATION:https://researchseminars.org/talk/WITP-seminar/2/ END:VEVENT BEGIN:VEVENT SUMMARY:Omer Blaes (UCSB) DTSTART:20200722T203000Z DTEND:20200722T213000Z DTSTAMP:20260422T225930Z UID:WITP-seminar/3 DESCRIPTION:Title: Magnetohydrodynamics and Convection in Accretion Disks: From Dwarf N ovae to Luminous Quasars\nby Omer Blaes (UCSB) as part of Winnipeg Ins titute for Theoretical Physics Seminar\n\n\nAbstract\nOne of the most powe rful sources of energy in the universe is the liberation of gravitational binding energy as plasma falls into a central object\, such as a black hol e. Such accretion flows are dynamically complex\, involving significant r otational support against gravity\, transport of angular momentum by magne tic turbulence\, and turbulent dissipation. Simulations of these processe s have had a checkered history of explaining observed accretion powered so urces in the universe. In this talk\, I will show how an additional compl icating factor\, opacity-driven convection\, actually has a profound effec t on the dynamics of these flows\, and might provide an explanation for a variety of observed phenomenology in luminous accretion flows around white dwarfs and supermassive black holes.\n LOCATION:https://researchseminars.org/talk/WITP-seminar/3/ END:VEVENT BEGIN:VEVENT SUMMARY:Ada Chan (York) DTSTART:20200812T200000Z DTEND:20200812T210000Z DTSTAMP:20260422T225930Z UID:WITP-seminar/4 DESCRIPTION:Title: Spectra properties of graphs and their quantum walks\nby Ada Chan (York) as part of Winnipeg Institute for Theoretical Physics Seminar\n\n\ nAbstract\nIn this talk\, we focus on the continuous-time quantum walk on graphs. We discuss three phenomena of the quantum walks: the ability of pe rfect transmission of information from one qubit to another\, called perfe ct state transfer\; the generation of entanglement between two qubits\, ca lled fractional revival\; and reaching uniform distribution at a certain t ime\, called instantaneous uniform mixing.\n\nWe use tools in algebraic gr aph theory to show the existence of graphs admitting some of these phenome na at arbitrarily small times.\n LOCATION:https://researchseminars.org/talk/WITP-seminar/4/ END:VEVENT BEGIN:VEVENT SUMMARY:Robert Brandenberger (McGill University) DTSTART:20201120T183000Z DTEND:20201120T193000Z DTSTAMP:20260422T225930Z UID:WITP-seminar/5 DESCRIPTION:Title: Stephen Hawking - A Personal Perspective\nby Robert Brandenberger (McGill University) as part of Winnipeg Institute for Theoretical Physics Seminar\n\n\nAbstract\nStephen Hawking was one of the leading theoretical physicists of his generation. I will give an overview of his ground-break ing contributions to science. I had the good fortune of being a postdoc in Stephen's group for two years\, and I will try to describe some of my str ong impressions of him as a person.\n LOCATION:https://researchseminars.org/talk/WITP-seminar/5/ END:VEVENT BEGIN:VEVENT SUMMARY:Seyda Ipek (Carleton University) DTSTART:20211005T170000Z DTEND:20211005T180000Z DTSTAMP:20260422T225930Z UID:WITP-seminar/6 DESCRIPTION:Title: Why are we here? Matter -- antimatter asymmetry of the universe\n by Seyda Ipek (Carleton University) as part of Winnipeg Institute for Theo retical Physics Seminar\n\n\nAbstract\nThe Standard Model of elementary pa rticles predicts that there should be equal amounts of matter and antimatt er in our universe. However everything around us\, rocks\, stars\, galaxie s\, etc. is made up of “matter” and not “antimatter”. What happene d to the antimatter in the Universe? This matter--antimatter asymmetry is a clear sign of new physics beyond the Standard Model. I will explain the new physics required for generating such an asymmetry and I will talk abou t specific models that do the job.\n LOCATION:https://researchseminars.org/talk/WITP-seminar/6/ END:VEVENT BEGIN:VEVENT SUMMARY:Evan McDonough (University of Winnipeg) DTSTART:20220128T183000Z DTEND:20220128T193000Z DTSTAMP:20260422T225930Z UID:WITP-seminar/7 DESCRIPTION:Title: The Light and Fuzzy Side of Dark Matter\nby Evan McDonough (Unive rsity of Winnipeg) as part of Winnipeg Institute for Theoretical Physics S eminar\n\n\nAbstract\nThe identity of dark matter remains a mystery\, desp ite decades of theorizing and detection efforts. This includes the mechani sm for its primordial production\, its interactions with itself or with vi sible matter\, and the very nature of dark matter\, which could range from a Bose-Einstein Condensate\, to Black Holes\, to a traditional particle. In this talk I will discuss new ideas for dark matter\, and how to experim entally test these ideas. I will focus on dark matter in the extreme low m ass range\, which may exhibit exciting new phenomena\, such as exotic phas es of matter and vortex formation. These models can be tested in a wide ar ray of experimental arenas\, ranging from the large scale structure of the universe to particle physics experiments\n LOCATION:https://researchseminars.org/talk/WITP-seminar/7/ END:VEVENT BEGIN:VEVENT SUMMARY:Jose Ezquiaga (University of Chicago) DTSTART:20220217T180000Z DTEND:20220217T190000Z DTSTAMP:20260422T225930Z UID:WITP-seminar/8 DESCRIPTION:Title: The gravitational wave universe through the lens\nby Jose Ezquiag a (University of Chicago) as part of Winnipeg Institute for Theoretical Ph ysics Seminar\n\n\nAbstract\nAs the horizon of our gravitational wave (GW) detectors extends to higher redshifts\, the chances that distant GWs enco unter some intervening matter distribution increase significantly. If a GW passes close enough to a galaxy\, multiple images of the same source wi ll be produced\, arriving at our detectors at different times and with dif ferent amplitudes and phases. In this talk I will describe current searche s for multiply lensed GW images and their challenges. I will also show how strongly lensed events could be identified with a single image if wavefor m distortions are identified\, and how these distortions might be confused with modified gravity if the search pipeline does not include lensed temp lates. Lensed GWs will provide unique information to constrain the matter distribution in the universe and will be one of the main targets of next g eneration detectors.\n LOCATION:https://researchseminars.org/talk/WITP-seminar/8/ END:VEVENT BEGIN:VEVENT SUMMARY:Nils Deppe (California Institute of Technology) DTSTART:20220317T170000Z DTEND:20220317T180000Z DTSTAMP:20260422T225930Z UID:WITP-seminar/9 DESCRIPTION:Title: Challenges for accurate gravitational wave astrophysics predictions\nby Nils Deppe (California Institute of Technology) as part of Winnipeg Institute for Theoretical Physics Seminar\n\n\nAbstract\nThe first detect ion of a binary neutron star merger through gravitational waves took place in 2017. The event was accompanied by counterpart detections all across t he electromagnetic spectrum and established that such events can produce s hort gamma-ray bursts and heavy elements. Despite the tremendous success\, our ability to model such merger events remains a major limiting factor i n understanding these rich high-energy collisions. The errors in numerical simulations of binary neutron star mergers are larger than experimental e rrors and difficult to quantify. Additionally\, while binary black hole si mulations are sufficiently accurate for current observatories like LIGO\, this will no longer be true for the next-generation ground-based gravitati onal-wave observatories like Cosmic Explorer and Einstein Telescope. I wil l discuss recent work combining breakthroughs in parallel computing and nu merical algorithms that are necessary to take full advantage of current an d future multimessenger gravitational wave detections.\n LOCATION:https://researchseminars.org/talk/WITP-seminar/9/ END:VEVENT BEGIN:VEVENT SUMMARY:Alex Buchel (Western Ontario/Perimeter Institute) DTSTART:20220606T160000Z DTEND:20220606T170000Z DTSTAMP:20260422T225930Z UID:WITP-seminar/10 DESCRIPTION:Title: Dynamical fixed points in strongly coupled holographic systems\n by Alex Buchel (Western Ontario/Perimeter Institute) as part of Winnipeg I nstitute for Theoretical Physics Seminar\n\n\nAbstract\nTypically\, an int eractive system evolves towards thermal equilibrium\, with hydrodynamics r epresenting a universal framework for its late-time dynamics. Classificati on of the dynamical fixed points (DFPs) of a driven Quantum Field Theory ( with time dependent coupling constants\, masses\, external background fiel ds\, etc.) is unknown. We use holographic framework to analyze such fixed points in one example of strongly coupled gauge theory\, driven by homogen eous and isotropic expansion of the background metric - equivalently\, a l ate-time dynamics of the corresponding QFT in Friedmann-Lemaitre-Robertson -Walker Universe. We identify DFPs that are perturbatively stable\, and th ose that are perturbatively unstable\, computing the spectrum of the quasi normal modes in the corresponding holographic dual. We further demonstrate that a stable DFP can be unstable non-perturbatively\, and explain the ro le of the entanglement entropy density as a test for a non-perturbative s tability. Finally\, we demonstrated that a driven evolution might not have a fixed point at all: the entanglement entropy density of a system can gr ow without bounds.\n LOCATION:https://researchseminars.org/talk/WITP-seminar/10/ END:VEVENT BEGIN:VEVENT SUMMARY:Kyle Shiells (University of Manitoba) DTSTART:20221103T193000Z DTEND:20221103T203000Z DTSTAMP:20260422T225930Z UID:WITP-seminar/11 DESCRIPTION:Title: Nuclear Femtography: probing the inside of the nucleon\nby Kyle Shiells (University of Manitoba) as part of Winnipeg Institute for Theoret ical Physics Seminar\n\n\nAbstract\nAround the turn of the millennium\, ex citing new ways to study hadronic structure were proposed. The so-called G eneralized parton distribution functions (GPDs) hold unprecedented informa tion about the structure of hadrons. For instance\, they can tell us how t he proton and neutron acquire their observable spin of 1/2 through what ar e called spin sum rules. In the first part of this talk I will discuss som e of the important physics of GPDs\, including spin sum rules\, focusing o n ones which are most accessible experimentally. GPDs however\, can only b e probed from a relatively new line of challenging deeply virtual exclusiv e scattering experiments. One such flagship process for doing so is Deeply Virtual Compton scattering. I will highlight the phenomenological relatio nship between these observables and the GPDs. The greater scheme of the gl obal extraction of GPDs will also heavily rely on available and upcoming l attice QCD data\, making it unique to the previous global analyses seen in the extraction of parton distribution functions from deep inelastic scatt ering processes. I will discuss our approach to modelling and extracting t he GPDs from these global constraints\, which involves a unique applicatio n of complex analysis and non-linear fitting techniques.\n LOCATION:https://researchseminars.org/talk/WITP-seminar/11/ END:VEVENT END:VCALENDAR