Infosheet (March 21st, 2017)

Queen's University - Department of Mathematics and Statistics


Tuesday, March 21

Dynamics Seminar

Time: 3.30 p.m.

Place: Jeffery 422

Speaker: Francesco Cellarosi, Queen’s University

Title: The Impossible Pointwise Ergodic Theorem in Infinite Ergodic Theory

Abstract Attached

Wednesday, March 22

Curves Seminar

Time: 3:30 pm.

Place: Jeffery 422

Speaker: Mike Roth

Title: G-linearizations of line bundles II

Abstract Attached

Thursday, March 23

Math Club

Time: 5:30 p.m.

Place: Jeffery 118

Speaker: Jamie Mingo

Title: The Lemniscate and Generalized Trigonometric Functions

Abstract Attached

Friday, March 24

Number Theory Seminar

Time: 10:30 a.m.

Place: Jeffery 422

Speaker: Mike Roth

Title: A Liouville approximation theorem for varieties and an application to cubic surfaces

Abstract Attached

Friday, March 24

Department Colloquium

Time: 2:30 p.m.

Place: Jeffery 234

Speaker: Ioana Dumitriu, University of Washington, Seattle

Title: Spectra of random regular and quasi-regular graphs

Abstract Attached

Monday, March 27

Seminar in Free Probability

Time: 2:30 p.m.

Place: Jeffery 202

Speaker: Yinzheng Gu, Queen’s University

Title: Analytic subordination for bi-free convolution, Part II

Abstract Attached

Items for the Info Sheet should reach Anne ( burnsa@queensu.ca) by noon on Monday. The Info Sheet is published every Tuesday.


CALCULATOR EXAM POLICY , the official calculator is a Casio fx-991, or one with a blue sticker as issued by School of Business. All exam cover pages must only refer to these calculators only; any other exam cover, including other calculators (ie gold sticker) will not be accepted by the exams office. Proctors are going to be instructed to be less lenient with calculators that aren’t Casio fx-991 (or blue sticker from COMM), and will likely to be taking them away.


Tuesday, March 21, 3:30 p.m. Jeffery 422 - Dynamics Seminar

Speaker: Francesco Cellarosi

Title: The Impossible Pointwise Ergodic Theorem in Infinite Ergodic Theory

Abstract: I will discuss a classical theorem by Aaronson, which states that in the case of a conservative ergodic transformation on a sigma-finite infinite measure space, there is no normalizing sequence for the ergodic sums yielding almost everywhere convergence, unlike the classical pointwise ergodic theorem by Birkhoff.


Wednesday, March 22, 3:30 p.m. Jeffery 422 - Curves Seminar

Speaker: Mike Roth

Title: G-linearizations of line bundles II

Abstract: We will prove the exactness of the basic sequence relating Pic^G(X) and Pic(X), and discuss related topics.


Thursday, March 23, 5:30 p.m. Jeffery 118 - Math Club

Speaker: Jamie Mingo

Title: The Lemniscate and Generalized Trigonometric Functions

Abstract: Since ancient times there have been two ways of measuring an angle: the rise over the run, or as a fraction of a circle. We use the trigonometric functions to convert a measurement in one system to the other. The usual sine and cosine functions are often called the circular functions. A similar construction can be applied to a hyperbola resulting in the hyperbolic sine and cosine functions. In the 18th century Fagnano and Euler worked out the corresponding functions for the lemniscate.

We will discuss the basic properties of the lemniscate functions and indicate some of their connections to current research.


Friday, March 24, 10:30 a.m. Jeffery 422 - Number Theory Seminar

Speaker: Mike Roth

Title: A Liouville approximation theorem for varieties and an application to cubic surfaces

Abstract: Diophantine approximation studies the problem of approximating an algebraic point by rational ones. Results in Diophantine approximation are used to deduce Diophantine results from geometric conditions.

The first results on Diophantine approximation were by Dirichlet and Liouville, and concern approximation on the real line. Liouville’s result was later greatly improved by Klaus Roth. In general Roth’s theorem is much better than Liouville’s theorem, the exception being when the point being approximated is itself rational.

This talk will give an extension of Liouville’s theorem to algebraic varieties, and an application to cubic surfaces.


Friday, March 24, 2:30 p.m. Jeffery 234 - Department Colloquium

Speaker: Ioana Dumitriu

Title: Spectra of random regular and quasi-regular graphs

Abstract: The spectra of random graphs and networks have been widely studied in the last two decades, both in theoretical contexts (relating to random matrices and universality) and practical ones (with applications to mixing, sampling, community detection). From a random matrix perspective, the "natural" random graphs have independent edges (Erdos-Renyi and Chung-Lu-Vu models, with or without block structure); however, regular graphs have also been shown to share many of the spectral properties of the independent-edge ones. Recently, some of these studies have been extended to quasi-regular random graphs. We will survey some of these results and potential applications to community detection.


Monday, March 27, 2:30 p.m. Jeffery 202

Seminar in Free Probability and Random Matrices

Speaker: Yinzheng Gu

Title: Analytic subordination for bi-free convolution, Part II

Abstract: We discuss some analytic properties of the additive bi-free convolution, both scalar-valued and operator-valued. We show that using the one-variable subordination functions associated with the additive free convolution, simple formulas for additive bi-free convolutions can be derived. As an application, we prove a result about atoms of the additive bi-free convolution.

Seminar website: http://www.mast.queensu.ca/~mingo/seminar/

Contact Info

Department of Math & Stats
Jeffery Hall, 48 University Ave.
Kingston, ON Canada, K7L 3N6
Phone: (613) 533-2390
Fax: (613) 533-2964
mathstat@mast.queensu.ca
Office Hours: 8:30am-12:00pm & 1:00pm-4:30pm

Search