CMSA SPECIAL LECTURE SERIES ON QUANTUM COHOMOLOGY, NAKAJIMA VARETIES AND QUANTUM GROUPS: | Artan SheshmaniQGM & CMSA |
Computing GW Invariants |

on Tuesday, February 20, 2018, at 1:00 - 3:00 pm in CMSA Building, 20 Garden Street, Room G10 | ||

Genus zero invariants of the projective plane |

LOGIC SEMINAR: | Andrew Brooke-TaylorUniversity of Leeds |
Products of CW complexes: the full story |

on Tuesday, February 20, 2018, at 5:15 pm in Science Center 507 | ||

CW complexes are used extensively in algebraic topology as a suitable class of spaces to work with, but the product of two CW complexes need not be a CW complex, as shown by Dowker. Whitehead and Milnor gave sufficient conditions on the two spaces for the product to be a CW complex, but until now the known characterisations of those pairs of CW complexes with product a CW complex relied on set-theoretic assumptions about the whole universe, such as the Continuum Hypothesis. In this talk I will present a complete characterisation, valid without assuming any extra set-theoretic axioms, of those pairs of CW complexes whose product is a CW complex. |

NUMBER THEORY SEMINAR: | Juan Rivera-LetelierUniversity of Rochester |
Hecke and Linnik |

on Wednesday, February 21, 2018, at 3:00 PM in Science Center 507 | ||

A description of the equidistribution properties of Hecke correspondances acting on the moduli space of p-adic elliptic curves. As an application we show that for every finite set of primes S, there is at most a finite number of singular moduli that are S-units. A key ingredient is a p-adic version Linnik's theorem on the asymptotic distribution of integer points on spheres. This is a joint work with Sebastian Herrero and Ricardo Menares. |

CENTER OF MATHEMATICAL SCIENCES AND APPLICATIONS COLLOQUIUM: | Don RubinHarvard Statistics |
Essential concepts of causal inference — a remarkable history |

on Wednesday, February 21, 2018, at 4:30 PM in CMSA Building, 20 Garden Street, Room G10 | ||

I believe that a deep understanding of cause and effect, and how to estimate causal effects from data, complete with the associated mathematical notation and expressions, only evolved in the twentieth century. The crucial idea of randomized experiments was apparently first proposed in 1925 in the context of agricultural field trails but quickly moved to be applied also in studies of animal breeding and then in industrial manufacturing. The conceptual understanding seemed to be tied to ideas that were developing in quantum mechanics. The key ideas of randomized experiments evidently were not applied to studies of human beings until the 1950s, when such experiments began to be used in controlled medical trials, and then in social science — in education and economics. Humans are more complex than plants and animals, however, and with such trials came the attendant complexities of non-compliance with assigned treatment and the occurrence of “Hawthorne" and placebo effects. The formal application of the insights from earlier simpler experimental settings to more complex ones dealing with people, started in the 1970s and continue to this day, and include the bridging of classical mathematical ideas of experimentation, including fractional replication and geometrical formulations from the early twentieth century, with modern ideas that rely on powerful computing to implement aspects of design and analysis. |

INFORMAL DYNAMICS & GEOMETRY SEMINAR: | Ian BiringerBoston College |
Convex cores of thick hyperbolic 3-manifolds with bounded rank |

on Wednesday, February 21, 2018, at 4:00 PM in Science Center 530 | ||

I’ll describe a geometric decomposition of the convex core of an epsilon-thick hyperbolic 3-manifold with bounded rank. As a consequence, every such convex core is (1,C)-quasi-isometric to a metric graph, for some uniform C. |

CMSA SPECIAL LECTURE SERIES ON QUANTUM COHOMOLOGY, NAKAJIMA VARETIES AND QUANTUM GROUPS: | Artan SheshmaniQGM & CMSA |
Computing GW Invariants |

on Thursday, February 22, 2018, at 1:00 - 3:00 pm in CMSA Building, 20 Garden Street, Room G10 | ||

Genus zero invariants of Calabi-Yau threefolds |

JOINT DEPARTMENT OF MATHEMATICS AND CMSA RANDOM MATRIX AND PROBABILITY THEORY SEMINAR: | Mustazee RahmanMIT |
On shocks in the TASEP |

on Friday, February 23, 2018, at 3:30 pm in CMSA Building, 20 Garden Street, G02 | ||

The TASEP particle system runs into traffic jams when the particle density to the left is smaller than the density to the right. Macroscopically, the particle density solves Burgers' equation and traffic jams correspond to its shocks. I will describe work with Jeremy Quastel on a specialization of the TASEP shock whereby we identify the microscopic fluctuations around the shock by using exact formulas for the correlation functions of TASEP and its KPZ scaling limit. The resulting laws are related to universal laws of random matrix theory. |

MATHEMATICAL PHYSICS SEMINAR: | Xinqi GongInstitute for Mathematical Sciences, Rennin University of China |
Mathematical Intelligence Applications in Bio-medical Problems |

on Friday, February 23, 2018, at 3:00 pm in Jefferson 250 | ||

The intersection among mathematics, information and biology has becoming more and more interesting and important. Many studies in this direction have led to developments of theories, methods and applications. But the too fast advancing of nowadays forefront information technology and biology knowledge, have triggered two obviously emerging phenomena, tremendous brand-new peaks accessible by new kinds of efforts, randomly meaningless results by in-correct intersections. Here I will show some of our recent results in developing and distinguishing efficiently intelligent approaches and applications for computational molecular biology and medical problems, such as protein structure-function-interaction prediction and pancreas cancer CT image analysis using algorithms like Fast Fourier transform, Monte Carlo, and deep learning, and some new designed physical and geometrical features. |

CENTER OF MATHEMATICAL SCIENCES AND APPLICATIONS MATHEMATICAL PHYSICS SEMINAR: | Jordan KellerBHI |
Linear Stability of Schwarzschild Black Holes |

on Monday, February 26, 2018, at 12:00 PM in CMSA Building, 20 Garden Street, Room G10 | ||

The Schwarzschild black holes comprise a static, spherically symmetric family of black hole solutions to the vacuum Einstein equations. The physical relevance of such solutions is intimately related to their stability under gravitational perturbations. We present results on the linear stability of the Schwarzschild black holes, joint work with Pei-Ken Hung and Mu-Tao Wang. |

CMSA SPECIAL LECTURE SERIES ON QUANTUM COHOMOLOGY, NAKAJIMA VARETIES AND QUANTUM GROUPS: | Artan SheshmaniQGM & CMSA |
Quantum Cohomology |

on Tuesday, February 27, 2018, at 1:00 - 3:00 pm in CMSA Building, 20 Garden Street, Room G10 | ||

Small Quantum Cohomology (Definition and Properties) I |

CMSA HOMOLOGICAL MIRROR SYMMETRY FOCUSED LECTURE SERIES: | Colin DiemerIHES |
Moduli spaces of Landau-Ginzburg models and (mostly Fano) HMS |

on Tuesday, February 27, 2018, at 3:00 - 4:00 PM in CMSA Building, 20 Garden Street, Room G10 | ||

Tuesday, Feb. 28 and Thursday, March 1: Mirror symmetry as a general phenomenon is understood to take place near the large complex structure limit resp. large radius limit, and so implicitly involves degenerations of the spaces under consideration. Underlying most mirror theorems is thus a mirror map which gives a local identification of respective A-model and B-model moduli spaces. When dealing with mirror symmetry for Calabi-Yau's the role of the mirror map is well-appreciated. In these talks I'll discuss the role of moduli in mirror symmetry of Fano varieties (where the mirror is a Landau-Ginzburg (LG) model). Some topics I expect to cover are a general structure theory of moduli of LG models (follows Katzarkov, Kontsevich, Pantev), the interplay of the topology of LG models with autoequivalence relations in the Calabi-Yau setting, and the relationship between Mori theory in the B-model and degenerations of the LG A-model. For the latter topic we'll focus on the case of del Pezzo surfaces (due to unpublished work of Pantev) and the toric case (due to the speaker with Katzarkov and G. Kerr). Time permitting, we may make some speculations on the role of LG moduli in the work of Gross-Hacking-Keel (in progress work of the speaker with T. Foster). |

LOGIC SEMINAR: | Alexander Van AbelCity University of New York |
The Feferman-Vaught Theorem and the Product of All Prime Finite Fields |

on Tuesday, February 27, 2018, at 5:15 pm in Science Center 507 | ||

The Feferman-Vaught Theorem in model theory gives a sort of upper bound on the complexity of definable subsets in a product structure. We show how this theorem implies that subsets whose boundary is dense (in the product topology where every factor structure has the discrete topology) are undefinable. We also show how the upper bound in the F.V. Theorem is the best possible, in the case of the language of rings where each factor structure is an integral domain. Finally, we apply these results to the ring $\prod_{p prime} F_p$, the product of all finite prime fields, and obtain a quantifier elimination result for the structure. |

CMSA SPECIAL LECTURE SERIES ON QUANTUM COHOMOLOGY, NAKAJIMA VARETIES AND QUANTUM GROUPS: | Artan SheshmaniQGM & CMSA |
Quantum Cohomology |

on Thursday, March 01, 2018, at 1:00 - 3:00 pm in CMSA Building, 20 Garden Street, Room G10 | ||

Small Quantum Cohomology (Definition and Properties) II |

CENTER OF MATHEMATICAL SCIENCES AND APPLICATIONS HOMOLOGICAL MIRROR SYMMETRY FOCUSED LECTURE SERIES: | Colin DiemerIHES |
Moduli spaces of Landau-Ginzburg models and (mostly Fano) HMS |

on Thursday, March 01, 2018, at 3:00 - 4:00 PM in CMSA Building, 20 Garden Street, Room G10 | ||

Tuesday, Feb. 28 and Thursday, March 1: Mirror symmetry as a general phenomenon is understood to take place near the large complex structure limit resp. large radius limit, and so implicitly involves degenerations of the spaces under consideration. Underlying most mirror theorems is thus a mirror map which gives a local identification of respective A-model and B-model moduli spaces. When dealing with mirror symmetry for Calabi-Yau's the role of the mirror map is well-appreciated. In these talks I'll discuss the role of moduli in mirror symmetry of Fano varieties (where the mirror is a Landau-Ginzburg (LG) model). Some topics I expect to cover are a general structure theory of moduli of LG models (follows Katzarkov, Kontsevich, Pantev), the interplay of the topology of LG models with autoequivalence relations in the Calabi-Yau setting, and the relationship between Mori theory in the B-model and degenerations of the LG A-model. For the latter topic we'll focus on the case of del Pezzo surfaces (due to unpublis |

CMSA SPECIAL LECTURE SERIES ON QUANTUM COHOMOLOGY, NAKAJIMA VARETIES AND QUANTUM GROUPS: | Artan SheshmaniQGM & CMSA |
Quantum Cohomology |

on Tuesday, March 06, 2018, at 1:00 - 3:00 pm in CMSA Building, 20 Garden Street, Room G10 | ||

Big Quantum Cohomology I |

CMSA SPECIAL LECTURE SERIES ON QUANTUM COHOMOLOGY, NAKAJIMA VARETIES AND QUANTUM GROUPS: | Artan SheshmaniQGM & CMSA |
Quantum Cohomology |

on Thursday, March 08, 2018, at 1:00 - 3:00 pm in CMSA Building, 20 Garden Street, Room G10 | ||

Big Quantum Cohomology II |

CMSA SPECIAL LECTURE SERIES ON QUANTUM COHOMOLOGY, NAKAJIMA VARETIES AND QUANTUM GROUPS: | Artan SheshmaniQGM & CMSA |
Quantum Cohomology |

on Tuesday, March 13, 2018, at 1:00 - 3:00 pm in CMSA Building, 20 Garden Street, Room G10 | ||

GW potential |

CMSA SPECIAL LECTURE SERIES ON QUANTUM COHOMOLOGY, NAKAJIMA VARETIES AND QUANTUM GROUPS: | Artan SheshmaniQGM & CMSA |
Quantum Cohomology |

on Thursday, March 15, 2018, at 1:00 - 3:00 pm in CMSA Building, 20 Garden Street, Room G10 | ||

WDVV equation |

CMSA SPECIAL LECTURE SERIES ON QUANTUM COHOMOLOGY, NAKAJIMA VARETIES AND QUANTUM GROUPS: | Artan SheshmaniQGM & CMSA |
GW Invariants via Quantum Cohomology |

on Tuesday, March 20, 2018, at 1:00 - 3:00 pm in CMSA Building, 20 Garden Street, Room G10 | ||

The P^2 case |

CMSA SPECIAL LECTURE SERIES ON QUANTUM COHOMOLOGY, NAKAJIMA VARETIES AND QUANTUM GROUPS: | Artan SheshmaniQGM & CMSA |
GW Invariants via Quantum Cohomology |

on Thursday, March 22, 2018, at 1:00 - 3:00 pm in CMSA Building, 20 Garden Street, Room G10 | ||

The Quintic threefold case |