Date: | November 27, 2017 |

Time: | 3:00PM - 4:00PM |

Location: | BLOC 628 |

Speaker: | Souvik Goswami, TAMU |

Title: | Higher Arithmetic Chow Groups - Part 2 |

Abstract: | We continue in our quest to define an analogue of arithmetic Chow groups, for higher Chow groups. In this talk, I will introduce the notion of higher Chow groups a la Bloch, and then define an arithmetic version of it. We will also propose an intersection theory, which generalizes the one given by Gillet and Soul ́e. This is a joint work (in progress) with Jos ́e Ignacio Burgos Gil from ICMAT, Madrid. |

Date: | November 28, 2017 |

Time: | 4:00PM - 5:00PM |

Location: | BLOC 628 |

Speaker: | Semyon Dyatlov, MIT |

Title: | TBA |

Abstract: | TBA |

Date: | November 28, 2017 |

Time: | 5:00PM - 6:00PM |

Location: | BLOC 628 |

Speaker: | P. Sarin, TAMU |

Title: | Surgery cont'd |

Date: | November 29, 2017 |

Time: | 1:45PM - 2:45PM |

Location: | BLOC 220 |

Speaker: | Brad Rodgers, University of Michigan |

Title: | On the distribution of Rudin-Shapiro polynomials |

Abstract: | Rudin-Shapiro polynomials are a special sequence of trigonometric polynomials with all coefficients equal to 1 or -1 which do not become too large. In this talk I will discuss conjectures of B. Saffari and H. Montgomery regarding the distribution of these polynomials, and outline how these conjectures were resolved by making use of an analogy to random walks on compact groups. Prerequisites will be kept to a minimum. |

Date: | November 29, 2017 |

Time: | 3:00PM - 4:00PM |

Location: | BLOC 628 |

Speaker: | Laura Saavedra, Universidad Politécnica de Madrid |

Title: | TBA |

Date: | November 29, 2017 |

Time: | 4:00PM - 5:00PM |

Location: | Bloc 220 |

Speaker: | Anne Shiu, Texas A&M University |

Title: | Geometry and dynamics of reaction systems |

Abstract: | Chemical reaction networks are directed graphs in which each edge represents a chemical reaction. The most basic kinetics to assign to reaction networks are those of mass-action, first introduced 150 years ago by Guldberg and Waage: the rate at which each reaction occurs is proportional to the product of the concentrations of its reactants. The systematic study of the resulting polynomial ordinary differential equations began in the 1970s, and in recent years, this area has seen renewed interest, due in part to applications to systems biology. This talk will survey progress on long-standing questions pertaining to the dynamics of reaction systems, particularly their multistationarity and long-term stability, using methods from combinatorics and polyhedral as well as toric geometry. |

Date: | November 29, 2017 |

Time: | 5:30PM - 6:30PM |

Location: | BLOC 628 |

Speaker: | Peter Howard |

Title: | Preparing for Spring 2018 |

Date: | November 29, 2017 |

Time: | 6:00PM - 7:00PM |

Location: | BLOC 220 |

Speaker: | Dr. Raymundo Arroyave, Texas A&M University, Department of Materials Science and En |

Title: | New Frontiers in Matherials Discovery |

Abstract: | While it may seem like the title of this talk has a typo, I really meant it! Many of society’s most pressing challenges require the development of new technologies, which in turn often require the development of new materials. Materials discovery, however, is extremely time-consuming. Because of this, the field of materials science is rapidly trying to adapt new methods and frameworks to accelerate the discovery of materials. In this talk, I will provide some examples from my own research program where we have used advanced mathematical and computational techniques to discover new materials or improve existing ones. The examples I will talk about use ideas from mathematical optimization, search, informatics, artificial intelligence, operations research, optimal learning, and even game theory to discover new materials. I will show how using these techniques we have been able to discover and develop new materials at a rate that is significantly faster than using traditional methods. |

Date: | November 30, 2017 |

Time: | 2:00PM - 3:00PM |

Location: | *BLOC 220* |

Speaker: | Ronghui Ji, IUPUI |

Title: | From relative amenability to relative soficity for countable groups |

Abstract: | We define a relative soficity for a countable group with respect to a family of subgroups. A group is sofic if and only if it is relatively sofic with respect to the family consisting of only the trivial subgroup. When a group is relatively amenable with respect to a family of subgroups, then it is relatively sofic with respect to the family. We show that if a group is relatively sofic with respect to a family of sofic subgroups, then the group is sofic. This in particular generalizes a result of Elek and Szabo. An example of relatively amenable group G with respect to an infinite family of subgroups F is constructed so that G is not relatively amenable with respect to any finite subfamily of F. |

Date: | November 30, 2017 |

Time: | 2:45PM - 3:45PM |

Location: | BLOC 628 |

Speaker: | Cesar Galindo, Universidad de los Andes |

Title: | Pointed finite tensor categories over abelian groups |

Abstract: | In this talk we will give a characterization of finite pointed tensor categories obtained as de-equivariantizations of finite-dimensional pointed Hopf algebras over abelian groups only in terms of the (cohomology class of the) associator of the pointed part. As an application, we will prove that every coradically graded pointed finite braided tensor category is a de-equivariantization of a finite dimensional pointed Hopf algebras over an abelian group. This talk is base on arXiv:1707.05230, joint work with Iván Angiono. |

Date: | November 30, 2017 |

Time: | 3:00PM - 4:00PM |

Location: | BLOC 220 |

Speaker: | Patricio Gallardo , Washington University, St. Louis |

Title: | TBA |

Date: | December 1, 2017 |

Time: | 1:50PM - 2:50PM |

Location: | BLOC 628 |

Speaker: | Mahmood Ettehad, Texas A&M University |

Title: | Network graph reconstruction from path correlations (joint with Inverse Problems Seminar) |

Date: | December 1, 2017 |

Time: | 1:50PM - 2:50PM |

Location: | BLOC 628 |

Speaker: | Mahmood Ettehad, Texas A&M University |

Title: | Network graph reconstruction from path correlations (Joint with Math Physics and Harmonic Analysis seminar)) |

Date: | December 1, 2017 |

Time: | 3:00PM - 4:00PM |

Location: | BLOC 117 |

Speaker: | Carlos Arreche, UT Dallas |

Title: | Projectively integrable linear difference equations and their Galois groups |

Abstract: | To a linear difference system S is associated a differential Galois group G that measures the differential-algebraic properties of the solutions. We say S is integrable if its solutions also satisfy a linear differential system of the same order, and we say S is projectively integrable if it becomes integrable “modulo scalars”. When the coefficients of S are in C(x) and the difference operator is either a shift, q-dilation, or Mahler operator, we show that if S is integrable then G is abelian, and if S is projectively integrable then G is solvable. As an application of these results one can show certain generating functions arising in combinatorics satisfy no algebraic differential equations. This is joint work with Michael Singer. |

Date: | December 1, 2017 |

Time: | 4:00PM - 5:00PM |

Location: | BLOC 628 |

Speaker: | Jose Rodriguez, University of Chicago |

Title: | Numerical computation of Galois groups and braid groups |

Abstract: | Galois groups are an important part of number theory and algebraic geometry. To a parameterized system of polynomial equations one can associate a Galois group whenever the system has k (finitely many) nonsingular solutions generically. This Galois group is a subgroup of the symmetric group on k symbols. Using random monodromy loops it has already been shown how to compute Galois groups that are the full symmetric group. In the first part of this talk, we show how to compute Galois groups that are proper subgroups of the full symmetric group. We give examples from formation shape control and algebraic statistics. In the second part, we discuss the generalization to braid groups. Braid groups were first introduced by Emil Artin in 1925 as a generalization of the symmetric group and have more refined information than the Galois group. We develop algorithms to compute a set of generators for these groups using homotopy continuation. We conclude with an implementation using Bertini.m2, an interface to the numerical algebraic geometry software Bertini through Macaulay2. This is joint work with Jonathan Hauenstein and Frank Sottile and with Botong Wang. |

Date: | December 1, 2017 |

Time: | 4:00PM - 5:00PM |

Location: | BLOC 220 |

Speaker: | Li Gao, University of Illinois at Urbana-Champaign |

Title: | TBA |

Abstract: | TBA |

Date: | December 6, 2017 |

Time: | 12:00PM - 1:00PM |

Location: | BLOC 628 |

Speaker: | Dr. Matthew Lewis, UT Southwest Medical Center, Radiology Department |

Title: | TBA |

Date: | December 6, 2017 |

Time: | 1:45PM - 2:45PM |

Location: | BLOC 220 |

Speaker: | Shin Hattori, Kyushu University |

Title: | TBA |

Date: | December 6, 2017 |

Time: | 3:00PM - 4:00PM |

Location: | BLOC 628 |

Speaker: | Chris Kees, Coastal and Hydraulics Laboratory, US Army ERDC |

Title: | TBA |

Date: | December 6, 2017 |

Time: | 4:00PM - 5:00PM |

Location: | Bloc 220 |

Speaker: | Florent Baudier, Texas A&M University |

Title: | TBA |

Date: | December 7, 2017 |

Time: | 12:00PM - 1:00PM |

Location: | Blocker 220 |

Speaker: | Kendra Kilmer, Texas A&M |

Title: | The First Day of Class - What Tone are We Setting for the Semester? |

Abstract: | People always talk about how important first impressions are. It is important for us, as teachers, to reflect about the first impression that we make with our students. I truly believe that the first day of class makes a big impact on our students’ mindsets throughout the semester. In this discussion, it is my hope that we can all reflect on how we run our first day of class and the impact it has on our students. |

Date: | December 8, 2017 |

Time: | 1:50PM - 2:50PM |

Location: | BLOC 628 |

Speaker: | Naser Talebi Zadeh, University of Wisconsin-Madison |

Title: | QUANTUM CHAOS ON RANDOM CAYLEY GRAPHS OF SL2 [Z/pZ] |

Abstract: | We investigate the statistical behavior of the eigenvalues and diameter of random Cayley graphs of SL2[Z/pZ] as the prime number p goes to infinity. We prove a density theorem for the number of exceptional eigenvalues of random Cayley graphs i.e. the eigenvalues with absolute value bigger than the optimal spectral bound. Our numerical results suggest that random Cayley graphs of SL2[Z/pZ] and the explicit LPS Ramanujan projective graphs of P1(Z/pZ) have optimal spectral gap and diameter as the prime number p goes to infinity. |

Date: | December 12, 2017 |

Time: | 3:00PM - 4:00PM |

Location: | BLOC 506A |

Speaker: | Prof. Kai Diethelm, Technische University at Braunschweig, Germany |

Title: | On the Principle of ``Fractionalization'' in Mathematical Modeling |

Abstract: | Traditional mathematical models for many phenomena in various different fields of science and engineering are based on the use of classical differential equations, i.e. on equations containing integer order derivatives. These models are usually well understood from an analytic point of view, in particular regarding the qualitative behavior of their solutions. The availability of such information is important for evaluating whether the mathematical model really reflects the actual properties that the process in question has, and thus for showing that the set of equations is indeed a suitable model for the concrete process. In many cases, it has been observed that a generalization of the classical models obtained by replacing the integer order derivative(s) by a derivative of fractional (i.e., non-integer) order leads to better quantitative agreement between the mathematical model and experimental data, but the knowledge about qualitative properties is frequently lacking. Thus, the question whether the fractional order model is in fact able to correctly reproduce the behavior that the underlying process must exhibit frequently remains unanswered. In this talk, specific examples from the life sciences are used to demonstrate potential approaches to handle such issues and point out possible pitfalls in this ``fractionalization'' procedure for differential equation based mathematical models. Parts of the work described in this presentation are based on results of the project READEX that has received funding from the European Union's Horizon 2020 research and innovation program under Grant Agreement No.\ 671657. |