4:00pm to 5:00pm - RH 306 - Applied and Computational Mathematics Solmaz Kia - (Mechanical and Aerospace Eng. Dept., University of California Irvine) TBA |
4:00pm - ISEB 1200 - Differential Geometry Pak-Yeung Chan - (UC San Diego) Hamilton-Ivey estimates for gradient Ricci solitons One special feature for the Ricci flow in dimension 3 is the |
2:00pm to 3:00pm - 510R Rowland Hall - Combinatorics and Probability Roman Vershynin - (UCI) Mathematics of synthetic data. II. Random walks. In this talk we will construct a superregular random walk, which locally looks like a simple random walk, but which globally deviates from the origin much slower than the Brownian motion. This random walk will become a crucial tool in the construction of a private measure. Joint work with March Boedihardjo and Thomas Strohmer, https://arxiv.org/abs/2204.09167 |
10:00am to 11:00am - Zoom - Number Theory Amita Malik - (Max Planck Institute) TBA |
11:00am - RH 306 - Harmonic Analysis Yizhe Zhu - (UCI) The characteristic polynomial of sums of random permutations Let $A_n$ be the sum of $d$ permutations matrices of size $n×n$, each drawn uniformly at random and independently. We prove that $\det( I_n−zA_n/\sqrt{d})$ converges when $n\to\infty$ towards a random analytic function on the unit disk. As an application, we obtain an elementary proof of the spectral gap of random regular digraphs with a sharp constant. Our results are valid both in the regime where $d$ is fixed and for $d$ slowly growing with $n$. Joint work with Simon Coste and Gaultier Lambert. |
1:00pm - Rowland 510R - Algebra Cris Negron - (University of Southern California) Vanishing tests for (quantum) group representations In this talk I will survey some results on the vanishing of (quantum) group representations, at the level of the stable category. Equivalently, I will discuss effective ways to test projectivity of a given finite-dimensional G-representation, where G your favorite finite (quantum) group. In the case of an elementary abelian p-group E, over k=\bar{F}_p, for example, Carlson tells us that an object V in rep(E) is projective if and only if V has projective restriction along each flat algebra map \alpha: k[t]/(t^p) -> k[E] into the group ring. One thus reduces a wild representation type calculation to a finite representation type calculation, via this P^{rank(E)}(k)-family of embeddings. I will provide an analogous vanishing result for the small quantum group u_q(L), which involves the introduction of a G/B-family of small quantum Borels and an analysis of certain ``noncommutative complete intersections”. This is joint work with Julia Pevtsova [arxiv:2012.15453, arxiv:2203.10764]. |
4:00pm to 5:00pm - MSTB 124 - Graduate Seminar Connor Mooney - (UC Irvine) TBA |