## Focus on Math: Alissa S. Crans

Date:  April 12th, 2018 4:00 PM 1170 TMCB

Title:  Frosting Fairness, Finally!

Abstract:  Many of us are familiar with how to slice a cake ensuring equal sized slices for all.  But what about those of us who want an equal amount of frosting as well?!  This question is a classic with the problem solvers amongst us.  In 1975, Martin Gardner considered a square cake cut into 7 pieces in his Scientific American column.  More than a decade earlier, H.S.M. Coxeter posed the problem for a square cake sliced into 9 pieces as an exercise in his book, Introduction to Geometry.  Together, we will solve this problem for a square cake cut into 5 pieces, and investigate the other cake shapes for which the same procedure will produce slices with equal cake and frosting.

Bio:  Alissa S. Crans has been recognized nationally for her enthusiastic ability to share and communicate mathematics, having been honored by the MAA with the Hasse Prize and Alder Award. Her research lies in the field of higher-dimensional algebra and is currently supported by a Simons Foundation Collaboration Grant. Alissa is known for her active mentoring of women and underrepresented students, as well as of junior faculty as a member of the MAA Project NExT leadership team. When not enticing students with the beauty of mathematics at Loyola Marymount University or sharing her enthusiasm for math in settings ranging from “Nerd Night Los Angeles” to public school classrooms, you can find her rehearsing with the Santa Monica College Wind Ensemble or on her quest to find the spiciest salsa in LA.

## Focus on Math: Dana Richards

The vast majority of mathematical puzzles ask for the existence of a solution. It is merely an exercise when the method is known and it is more of a puzzle when the method is not clear. An algorithmic puzzle takes this further by only asking for the method itself or a property of the method.  It is in this sense that much of computer science is puzzle solving. We discuss the theory behind this in the context of material taken from Martin Gardner’s Scientific American column. The answer to the following puzzle will be given:

There are five pirates dividing up 100 gold coins. Pirates are strictly ordered by seniority, are very logical and wish to live. The rule pirates use to divide gold is: (1) the most senior pirate suggests a division, (2) all pirates vote on it, (3) if at least half vote for it then it is done, otherwise the senior pirate is killed and the process starts over.  What happens?

Dana Richards is an associate professor of Computer Science at George Mason University. His research is on theoretical and algorithmic topics.  He has been a friend of Martin Gardner for nearly four decades and has edited Gardner’s book

The Colossal Book of Short Puzzles and Problems.

Join us at 4:00 on March 22nd to hear from Dana in 1170 TMCB.

## Colloquium: Dallas Smith (BYU)

Title: Hidden Network Symmetries

Abstract: Real-world networks often have a high degree of symmetry. Understanding a network’s symmetry can often provide insight into the network’s form or function. To this end, we have proposed a novel generalization of the notion of network (graph) symmetry which we refer to as latent symmetry. In this talk I will define latent symmetries and present a number of examples of real and theoretical networks which contain them. I will also explain properties of latent symmetries which suggest that they are potentially useful for revealing hidden structures in networks. I will conclude my talk by making a surprise connection between latent symmetries and perfect state transfer on quantum graphs.

Date: Thursday, March 15, 2018
Time: 4:00 PM
Room: 135 TMCB

## The William P. Thurston Lecture Colloquium: Michael Hutchings (University of California, Berkeley)

Talk title: Two or Infinitely Many Reeb Orbits

Abstract: What is the minimum number of periodic orbits of a vector field on a three-manifold? In general the answer is zero. However on (closed) three-manifolds, Reeb vector fields, which are important in connection with Hamiltonian dynamics, always have at least one periodic orbit. We discuss a theorem proved with Dan Cristofaro-Gardiner and Dan Pomerleano asserting that under mild assumptions, every Reeb vector field on a (closed, connected) three-manifold has either two or infinitely many Reeb orbits.

Date: Tuesday, March 13
Time: 4:00 pm
Room: 135 TMCB

## Imitation Game Movie Screening

Join the Math Department for a special screening of the imitation game March 23rd 6:00PM in 1170 TMCB

Synopsis:

In 1939, newly created British intelligence agency MI6 recruits Cambridge mathematics alumnus Alan Turing (Benedict Cumberbatch) to crack Nazi codes, including Enigma — which cryptanalysts had thought unbreakable. Turing’s team, including Joan Clarke (Keira Knightley), analyze Enigma messages while he builds a machine to decipher them. Turing and team finally succeed and become heroes, but in 1952, the quiet genius encounters disgrace when authorities reveal he is gay and send him to prison.

## Pi Day 2018

Be there or B2

Wednesday 3.14

Talmage Building Lobby  11:30 – 1:30 PM

Come join us for a pi eating contest, pin the mustache on Einstein, pi face paint, and more pi related fun. Make sure to brush up on the digits of pi for the pi recitation contest!
Limited edition Pi Day t-shirts will be on sale for \$10, starting March 5th in the Math Department office (275 TMCB).
Volunteers are needed to run booths at the event. Sign up in 275 TMCB. All volunteers will receive a free t-shirt.

In addition, ee will be having a special presentation after the festivities:

## Focus in Math: Emily Evans (BYU)

Talk Title: The Secret Life of Math

Abstract: How does computer-aided design work? How can you use probability to find integrals? How does Google know the best web pages to list? How are realistic animations of sand and snow made? How can you win your March Madness pool? Come hear the answer to these and other questions, and discover the secret life of math.

Date: Thursday, March 1, 2018
Place: 1170 TMCB
Time: 4:00 PM

## Statement on Women in Math

There is a poster from the “Women in Math” club circulating around the internet. The poster displayed the pictures of four faculty members in our department. It was done by a club member with good intentions. It was not meant to demean women or be satirical. We value women in mathematics and their contributions, and work to promote opportunities for women to succeed in mathematics.

## Colloquium: Skyler Simmons (SUU)

Title: Stability of Collision-Based Periodic n-Body Problems

Abstract: The Newtonian n-body problem describes the motion of n point masses interacting with each other with gravitational force. The physical laws governing this motion were codified by Newton in his Principia in 1686. Under Newton’s laws, two colliding bodies’ velocities increase without bound as they approach collision. Levi-Civita demonstrated that through a suitable change of variables, certain collisions could be regularized, allowing the orbit to be continued past the collision. Variations on Levi-Civita’s work continue to be used in the study of collision-based orbits today. In this talk, I will present a few periodic orbits featuring collisions, describe the methods used to study their stability, and present known results about a few orbits.

Date: Thursday, February 22, 2018
Time: 4:00 PM
Room: 135 TMCB

## Colloquium: Robert Snellman (University of California San Diego)

Title: Special Values of L-functions and Fitting Ideals

Abstract: The Main Conjecture in Iwasawa theory provides a deep connection between a certain p-adic zeta function and arithmetic data associated to class groups in p-power cyclotomic extensions. Proved by Mazur and Wiles, later generalized and proved by Wiles for totally real fields, the Main Conjecture can be interpreted in terms of a Fitting ideal. I will give an overview of the importance of higher Fitting ideals in the structure theory of modules, and provide a conjecture giving a relationship between higher Fitting ideals of Iwasawa modules and special values of L-functions.

Date: Thursday, February 15, 2018
Time: 4:00 PM
Room: 135 TMCB