# Mathematics Department

###### Mathematics Colloquium Seminar

##### Evita Nestoridi (Princeton University)

**Monday, January 21 - 12:00 pm**

**119 Physics**

Markov chains are random processes that retain no memory of the past. The mixing time of a Markov chain is the time it takes for it to reach equilibrium. During the last three decades, there has been...

###### Geometry/topology Seminar

##### Gonçalo Oliveira (Universidade Federal Fluminense, GMA-Instítuto de Matemática)

**Tuesday, January 22 - 3:15 pm**

**119 Physics**

I will describe joint work with Gavin Ball where we classify certain G2-Instantons on Aloff-Wallach spaces. This classification can be used to test ideas and explicitly observe various interesting...

###### Mathematics Colloquium Seminar

##### Nicholas Cook

**Wednesday, January 23 - 12:00 pm**

**119 Physics**

Let $G=G(N,p)$ be an Erd\H{o}s--R\'enyi graph on $N$ vertices (where each pair is connected by an edge independently with probability $p$). We view $N$ as going to infinity, with $p$ possibly going to...

###### Data Dialogue

##### Ytzachak Solomon (Brown University Math Dept.)

**Thursday, January 24 - 11:45 am**

**Gross Hall, Ahmadieh Family Grand Hall, Room 330**

Lunch: 11:45 am Seminar: Noon

###### Probability Seminar

##### Alex Blumenthal (University of Maryland, Mathematics)

**Thursday, January 24 - 3:15 pm**

**119 Physics**

It is anticipated that chaotic regimes (e.g., strange attractors) arise in a wide variety of dynamical systems, including those arising from the study of ensembles of gas particles and fluid mechanics...

###### Applied Math And Analysis Seminar

##### Courtney Paquette (University of Waterloo)

**Friday, January 25 - 12:00 pm**

**119 Physics**

Nonsmooth and nonconvex loss functions are often used to model physical phenomena, provide robustness, and improve stability. While convergence guarantees in the smooth, convex settings are well-...

###### Mathematical Biology Seminar

##### Andrew Brouwer (University of Michigan)

**Friday, January 25 - 1:30 pm**

**119 Physics**

Israel experienced an outbreak of wild poliovirus type 1 (WPV1) in 2013-14, detected through environmental surveillance of the sewage system. No cases of acute flaccid paralysis were reported, and the...

###### Applied Math And Analysis Seminar

##### Haihao Lu (MIT)

**Monday, January 28 - 12:00 pm**

**LSRC D106**

The gradient boosting machine (GBM) is one of the most successful supervised learning algorithms, and it has been the dominant method in many data science competitions, including Kaggle and KDDCup. In...

###### Number Theory Seminar

##### Ayla Gafni (University of Rochester)

**Wednesday, January 30 - 3:15 pm**

**119 Physics**

Fix an elliptic curve $E$ over $\mathbb{Q}$. An ''extremal prime'' for $E$ is a prime $p$ of good reduction such that the number of rational points on $E$ modulo $p$ is maximal or minimal in relation...