Title: Anomalies, Gauging, and Onsiteability
Abstract: I will discuss anomalies of ordinary and higher-form symmetries on the lattice. First, I will present systematic methods for diagnosing anomalies from symmetry defects. I will then describe a procedure for gauging and higher gauging of anomaly-free symmetries. Finally, I will explain the connection between gauging and anomalies and the notion of (higher) onsiteability.
Speaker: Julian Chaidez
Title: The conformally symplectic dynamics of characteristic foliations
Abstract: Any hypersurface in a contact manifold comes equipped with a natural dynamical system, called the characteristic foliation. Special cases include the suspension flow of a contactomorphism and the Liouville flow on a Liouville manifold. One may view the characteristic foliation as a kind of conformally symplectic dynamics.
In this talk, I will explain some recent work towards understanding the dynamics of characteristic foliations using tools from (partially) hyperbolic dynamics and ergodic theory. I will also explain applications to convex hypersurface theory, including a proof that convex hypersurfaces are not dense in the $C^2$-topology in dimension five, in sharp contrast to the seminal works of Giroux in dimension three and Honda-Huang in the $C^0$-topology.
Speaker: Andrew Waldron
Title: Quantum mechanics and contact geometry
Abstract: In this informal talk, I will discuss some relationships between quantum mechanics and contact geometry.
| Title: | No seminar this week: Della Pietra lecture |
Title: UNDERSTANDING COINCIDENCES
Abstract: Coincidences astound us. They can affect where we live (and with whom), work and all sorts of things. I will review ideas of Freud and Jung on the psychology of coincidences. I will also show that sometimes, a bit of thought shows 'it's not so surprising after all'. A small set of tools and examples lead to a checklist and ways of quantifying things. This is a math talk, but aimed at a very general audience.
Title: THE SEARCH FOR RANDOMNESS
Abstract: I will review some of our most primitive notions of random phenomena; flipping a coin, shuffling cards and throwing a dart at the wall. Thinking about things, we can show that usually we are lazy and things are not at all random. Physics and mathematics and just plain common sense come in. This is a math talk aimed at an undergraduate audience--it has lots of stories (and you can also go make money in a casino).
Title: When can spacetime emerge?
Abstract: Recent developments have taught us that some semiclassical spacetimes, in particular those containing closed universe components, cannot emerge from a usual holographic correspondence. In this talk, I will explain how one can get to this conclusion by using either quantum information theory or properties of the large N limit of AdS/CFT, and propose a criterion for detecting failures of spacetime emergence. If time permits, I will also comment on the connection to recent proposals for taking into account the presence of an observer in quantum gravity.
Reception at 4:00pm, Simons Center Lobby
Performance at 4:30pm, Simons Center Della Pietra Family Auditorium, room 103
For more information please visit: https://scgp.stonybrook.edu/archives/47634
Tittle: RANDOM WALK ON THE RANDOM GRAPH
Abstract: pick a random graph on n points by flipping a fair coin for each possible edge. Now do it again, independently. What's the chance the two graphs you get are isomorphic? Small? How small? When n= 100, less than 10^(-1300). Now, let n = infinity. Pick two graphs at random. the chance that they are isomorphic is one (!). this is THE random graph. I will illustrate its strange properties by studying random walk. This is a typical problem of probability in the presence of a random geometry. I will introduce 'Hardy's inequalities' for trees to get where we need to go. This is joint work with Sourav Chatterjee and Laurent Miclo.