Past Events

E.g., Jun 2, 2025

Chen-Chih Lai

Columbia University
Thermal effects on the deformation of a gas bubble in an incompressible fluid

October 10, 2024

Zoom Talk

We study the thermal decay of bubble oscillations in an incompressible fluid with surface tension. Particularly, we focus on the isobaric approximation [Prosperetti, JFM, 1991], under which the gas pressure within the bubble is spatially uniform and follows the ideal gas law. This model exhibits... Read more

  • Differential geometry
  • Mathematical Physics
  • Partial Differential Equations

Hong Wang

NYU
Szemeredi-Trotter theorem for tubes

October 10, 2024

MATH 225

We prove some Szemeredi-Trotter type estimates for tubes in the plane under some natural assumptions. Joint works with Ciprian Demeter and with Shukun Wu (in progress), which are based on the Furstenberg sets estimate proved by Orponen-Shmerkin, and Ren-W. Read more

  • Harmonic Analysis and Fractal Geometry

Milind Hegde

Columbia University
The scaling limit of the colored asymmetric simple exclusion process

October 9, 2024

In the colored asymmetric simple exclusion process, one places a particle of "color" $-k$ at each integer site $k \in \mathbb{Z}$. Particles attempt to swap places with an adjacent particle: at rate $q \in [0,1)$ if they are initially ordered (e.g., 1 then 2) and at rate 1 if ordered in reverse... Read more

  • Probability

George Berry

UBC
Math-Bio: Modeling evolution in dynamic populations: the decoupled Moran Process

October 9, 2024

ESB4133

The Moran process models the evolutionary dynamics between two competing types in a population, traditionally assuming a fixed population size. We investigate an extension to this process which adds ecological aspects through variable population sizes. For the original Moran process, birth and... Read more

  • Mathematical Biology

Shamil Asgarli

Santa Clara University
Chromatic quasisymmetric functions of the path graph

October 8, 2024

Zoom

The chromatic polynomial of a graph G counts the number of proper k-colorings of G. In 1995, Stanley extended this concept to define the chromatic symmetric function of a graph, which lives in the ring Sym of all symmetric functions. Building on this work, Shareshian and Wachs introduced the... Read more

  • Discrete mathematics

Sebastian Gant

UBC
Splitting stably free modules

October 7, 2024

UBC Math department

We study the question of when a generic stably free module splits off a free summand of a given rank. This question has the following geometric interpretation due to M. Raynaud. Let V(r,n) denote the Stiefel variety GL(n)/GL(n-r) over a field k. There is a projection map V(r,n) -> V(1,n)... Read more

  • Algebra and Algebraic geometry

Sebastien Picard

UBC
Non-Kahler Degenerations of Calabi-Yau Threefolds

October 4, 2024

ESB 2012 and Zoom

It was proposed in the works of Reid in the mathematics literature and Candelas-Green-Hubsch in the string theory literature to connect Calabi-Yau threefolds with different topologies by a process which degenerates 2-cycles and introduces new 3-cycles. This operation may connect a Kahler Calabi-... Read more

Dror Bar Natan

University of Toronto
The Strongest Genuinely Computable Knot Invariant in 2024

October 4, 2024

UBC

"Gennuinely computable" means we have computed it for random knots with over 300 crossings. "Strongest" means it separates prime knots with up to 15 crossings better than the less-computable HOMFLY-PT and Khovanov homology taken together. And hey, it's also meaningful and fun.

Further... Read more

  • Topology

Federico Trinca

UBC
Unstable minimal spheres in hyperkähler 4-manifolds with degree one Gauss lift

October 3, 2024

ESB 4133

Complex submanifolds of Kähler manifolds are prototypical examples of stable, minimal submanifolds of higher codimension. In 1990, Yau asked whether it was possible to classify stable minimal spheres in hyperkähler 4-manifolds, proposing that all stable minimal spheres are holomorphic for some... Read more

  • Differential geometry
  • Mathematical Physics
  • Partial Differential Equations

Sean Douglas

UBC
Extensions To The Fractional Chain Rule

October 2, 2024

ESB 4133 (PIMS Library)

In this talk, we establish a fractional chain rule in the context of weighted Triebel-Lizorkin spaces. This result notably extends the fractional chain rule to weighted Sobolev spaces with an integrability index less than one. Additionally, we determine an explicit relationship between the... Read more

  • Harmonic Analysis and Fractal Geometry