## Contact Info

Pure MathematicsUniversity of Waterloo

200 University Avenue West

Waterloo, Ontario, Canada

N2L 3G1

Departmental office: MC 5304

Phone: 519 888 4567 x33484

Fax: 519 725 0160

Email: puremath@uwaterloo.ca

Wednesday, September 30, 2015 — 3:30 PM EDT

Mohammad Mahmoud, Pure Mathematics, University of Waterloo

"Algorithmic Randomness: Introduction to Kolmogorov Complexity"

Last time we saw why the Kolmogorov complexity $K$ can be better than the plain complexity $C$ as it is subadditive and complexity doesn't dip. This time we are going to see more properties showing that $K$ matches our intuition. More precisely, (a) Incompressible (in the sense of $K$) strings have only short runs of zeros (i.e. blocks only consisting of zeros), and (b) Zeros and ones occur balancedly.

MC 5403

Wednesday, September 30, 2015 — 2:30 PM EDT

Jason Bell, Pure Mathematics, University of Waterloo

"The noncommutative Zariski Cancellation Problem"

Tuesday, September 29, 2015 — 2:30 PM EDT

Anton Mosunov, Pure Mathematics, University of Waterloo

"Congruence subgroups and examples of forms that are modular with respect to these subgroups"

This week, we will look at the definition of cusp forms, and consider the most famous example of the cusp form of weight 12, which is the discriminant function. Afterwords, we shall move to the discussion of congruence subgroups, and will look at forms that are modular with respect to particular congruence subgroups.

MC 5479

Tuesday, September 29, 2015 — 11:30 AM EDT

**Patrick Naylor, Pure Mathematics, University of Waterloo**

"Semisimplicity and the Hopkins--Levitski Theorem"

This semester we'll be meeting weekly to learn more about ring theory, mostly going through Lam's two books --- there are many interesting results in those books which will be "good to know". Starting off, we'll aim to learn the Hopkins--Levitski Theorem, one of whose (many) consequences is that the descending chain condition *implies* the ascending chain condition. Everyone is welcome. See you there!

MC 5403

Monday, September 28, 2015 — 9:30 PM EDT

**Ram Murty, Queen’s University **

“The theory of Ramanujan expansions”

Monday, September 28, 2015 — 4:00 PM EDT

**M. Ram Murty, Queen’s University **

“NEW DIRECTIONS IN SIEVE THEORY”

Friday, September 25, 2015 — 3:30 PM EDT

**Chris Schafhauser, Department of Pure Math, University of Waterloo**

“Quasidiagonal Traces and Crossed Products”

Thursday, September 24, 2015 — 2:30 PM EDT

**Blake Madill, Department of Pure Mathematics, University of Waterloo **

“On rings graded by semigroups with a unique product property”

Wednesday, September 23, 2015 — 2:30 PM EDT

**Anthony McCormick, Pure Math Department, University of Waterloo **

“Recent Methods for Computing the Hausdorff Dimension of a Self-Similar Set”

Tuesday, September 22, 2015 — 2:30 PM EDT

Juan Felipe Carmona, Universidad Antonio Nariño

"Flatness and CM-triviality in strongly minimal theories with a predicate"

Tuesday, September 22, 2015 — 2:30 PM EDT

**Anton Mosunov, Department of Pure Mathematics, University of Waterloo**

“Basic definitions and examples in the theory of modular forms”

Monday, September 21, 2015 — 4:00 PM EDT

**Michael F. Singer North Carolina State University **

“Differential Groups and the Gamma Function”

Wednesday, September 16, 2015 — 3:30 PM EDT

**Mohammad Mahmoud, Department of Pure Mathematics, University of Waterloo **

“Algorithmic Randomness: Introduction to Kolmogorov Complexity”

The topic for the Computability Learning Seminar this term will be Algorithmic Random- ness. We will be following Nies’s book, Computability and Randomness.

Wednesday, September 16, 2015 — 10:30 AM EDT

**Jaspar Wiart, Department of Pure Math, University of Waterloo **

“Nuclear and exact C*-algebras”

This will be an overview of the two definitions of nuclear and exact C*-algberas via com- pletely positive maps and exact sequences, and an outline of how the equivalence is established.

MC 5403

Monday, September 14, 2015 — 4:00 PM EDT

**Dinesh Thakur, University of Rochester **

“What should be pi, e, zeta(3), Gamma(1/7), if integers are replaced by polynomials?”

We will explain the title and talk about relations between these quantities.

MC 5501

*Refreshments will be served in MC 5403 at 3:30 p.m. Everyone is welcome to attend. *

University of Waterloo

200 University Avenue West

Waterloo, Ontario, Canada

N2L 3G1

Departmental office: MC 5304

Phone: 519 888 4567 x33484

Fax: 519 725 0160

Email: puremath@uwaterloo.ca

University of Waterloo

University of Waterloo

43.471468

-80.544205

200 University Avenue West

Waterloo,
ON,
Canada
N2L 3G1