# Past Events

E.g., Jun. 25, 2022

### Marc Roussel

University of Alberta, Lethbridge
Delays, large and small, in gene expression

June 22, 2022

Zoom - contact Katie Faulkner for link

The use of large delays (on the minute-to-hours timescales) to represent transcription and translation times is now well established. A variety of theoretical approaches have been taken to justify the introduction of these delays in models of gene expression. The potential dynamical consequences... Read more

• Mathematical Biology

### Max Lieblich

University of Washington
Murphy's Law for gerbes

June 22, 2022

This is a report on joint work with Daniel Bragg. We study what gerbes are possible as residual gerbes in natural moduli stacks. Among other things, we show that every gerbe with finite structure group arises as a residual gerbe in the stack of smooth projective curves. This gives examples of "... Read more

• Algebra and Algebraic geometry

### Marc Levine

University of Duisburg-Essen
Equivariant localization in quadratic enumerative geometry

June 20, 2022

We explain how to adapt the classical Atiyah-Bott torus localization methods to the computation of invariants, such as degrees of Euler classes, in the Grothendieck-Witt ring of quadratic forms, These quadratic enumerative invariants lift the usual integer-valued ones via the rank function, and... Read more

• Intercontinental Moduli and Algebraic Geometry Seminar

### Benjamin Antieau

Northwestern University
The K-theory of Z/p^n

June 15, 2022

I will report on joint work with Achim Krause and Thomas Nikolaus where we give an algorithm to compute the K-groups of rings such as Z/p^n. Read more

• Algebra and Algebraic geometry

### Eliahu Matzri

Bar Ilan Universiy
On the symbol length in Galois cohomology.

June 8, 2022

Fix a prime p and let F be a field with characteristic not p. Let G_F be the absolute Galois group of F and let \mu_{p^s} be the G_F-module of roots of unity of order dividing p^s in a fixed algebraic closure of F. Let \alpha \in H^n(F,\mu_{p^s}^{\otimes n}) be a symbol (i.e \alpha=a_1 U ... U... Read more

### Aravind Asok

University of Southern California
On P^1-stabilization in unstable motivic homotopy theory

June 1, 2022

I will discuss joint work with Tom Bachmann and Mike Hopkins regarding an analog of the Freudenthal suspension theorem in unstable motivic homotopy theory. To motivate the result, I will quickly introduce the unstable motivic homotopy category and discuss some concrete applications. Time... Read more

• Algebra and Algebraic geometry

### Caroline Colijn

SFU
Niven Lecture: Genomic Epidemiology in SARS-CoV-2: new models and challenges

May 31, 2022

UBC Mathematics Building, Room 100

Scientists around the world have sequenced over 2 million SARS-CoV-2 genomes in an effort to monitor and understand the evolution and transmission of this virus. Virus sequences can help us understand the emergence of new variants with new phenotypes, track the virus' geographical movements and... Read more

### Ruixiang Zhang

UC Berkeley
A stationary set method for estimating oscillatory integrals

May 19, 2022

https://ubc.zoom.us/j/68361900578?pwd=UkNHUzZMMkZoT0VJOFlVSWhDR0gzQT09

Given a polynomial $P$ of constant degree in $d$ variables and consider the oscillatory integral $$I_P = \int_{[0,1]^d} e(P(\xi)) \mathrm{d}\xi.$$ Assuming $d$ is also fixed, what is a good upper bound of $|I_P|$? In this talk, I will introduce a stationary set'' method that gives an upper... Read more

• Harmonic analysis

### Luca Ciandrini

U. Monpellier
Modelling mRNA translation: from the individual transcript to the impact on cellular physiology

May 18, 2022

Zoom - contact Katie Faulkner for link

One of the greatest challenges in biophysical models of translation is to identify coding sequence features that affect the rate of translation and therefore the overall protein production or the cellular growth rate.

I will first introduce a power series method to solve a translation... Read more

• Mathematical Biology

### Yumeng Ou

University of Pennsylvania
Unit distance type problems for point configurations in fractal sets

May 12, 2022

https://ubc.zoom.us/j/62198385847?pwd=ZWRTTGdQazU5cTE4bXlnK3duNGpBQT09

Abstract: The unit distance problem in discrete geometry studies the maximum number of times the unit distance can be achieved in a given point set. In 2015, D. Oberlin and R. Oberlin formulated an analogue of this problem in the continuous setting. In this talk, I'll discuss the problem and... Read more

• Harmonic analysis