Past Seminars - 2019

Date Speaker and Affiliation Title of the Talk (Click on title to view abstract) Subject Classification
22-11-2019 Dinesh Thakur: Rochester University

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

In this talk, which should be accessible to all undergraduates, we will explain the title, and explain how number theory understands interesting numbers and relations between them by building appropriate mathematical structures, from algebra, geometry, analysis.

18-11-2019 Trygve Johnsen and Madhusudan Manjunath

Matroids, Coding Theory and Syzygies: A Discussion Session.

We will discuss potential future directions in the interface between matroids, coding theory and syzygies. This will be a platform to share thoughts on this topic.

15-11-2019 Trygve Johnsen: The Artic University of Norway

Greedy weights for codes and matroids.

Greedy weights of linear codes measure the minimal support cardinality of chains of subcodes for a certain lexicographic order. We show how the problem of finding such weights can be studied by inspecting the poset of flats of the generator matroid, or better: the (dual) poset of cycles for the parity check matroid. The terms of a minimal resolution of the Stanley-Reisner ring of the independence complex of the parity check corresponds to the points of the poset. Optimal paths in the poset diagram, and optimal chains of non-zero component maps in a minimal resolution of the Stanley-Reisner ring. correspond to greedy weights Such maps can be constructed using poset homology, or studied indirectly, through the Taylor complex, which also provides a resolution, although not minimal.

13-11-2019 Chandranandan Gangopadhyay: The Institute of Mathematical Sciences, Chennai.

Quot schemes and Semistable Vector Bundles.

Let C be a smooth projective curve over an algebraically closed field k. Fix r, d ≥ 1. Let Q(r, d) be the quot scheme parametrizing degree d torsion quotients of the trivial vector bundle of rank r. Then we show that the universal kernel bundle over C × Q(r, d) and its pushforward to Q(r, d) are stable with respect to certain natural ample bundles over C × Q(r, d) and Q(r, d) respectively.

13-11-2019 Arnab Roy: INRIA, Nancy

Stabilization of a rigid body moving in a compressible viscous fluid.

In this talk, we discuss the stabilization of a fluid-structure interaction system of a viscous, compressible fluid and rigid ball in a three dimension space with an external force acting on the ball produced by a spring and a damper connecting the centre of the ball to a fixed point $h_1$. We prove global-in-time existence result for this model under the condition that the initial velocities are small and the center of mass of the body is sufficiently near to $h_1$. In this scenario, we discuss the asymptotic behaviour of the whole system.

12-11-2019 Saurav Bhaumik

Higgs bundles and the Hitchin fibration - II.

We will introduce Higgs bundles on curves, discuss the Hitchin fibration and its fibers in terms of spectral curves.

04-11-2019 Saurav Bhaumik

Higgs bundles and the Hitchin fibration.

We will introduce Higgs bundles on curves, discuss the Hitchin fibration and its fibers in terms of spectral curves.

08-11-2019 Dilip Patil: IISc Bengaluru

Module of Kahler Differentials, smooth morphisms, Cohen Structure Theorems.

(During the week 03 Nov – 08 Nov, 2019) We continue to study smooth morphisms. The purpose of these two lectures is : (1) Definitions and Basic properties of the Module of Käher differentials. (2) Prove a criterion for when a quotient of a formally smooth algebra is again formally smooth. (3) Prove a characterisation of when a morphism is smooth called the J a c o b i a n c r i - t e r i o n. This is a preparation for the proof of Cohen’s structure theorem for complete local rings in the inequicharacteritic case.

07-11-2019 Tony Puthenpurakal

An application of triangulated categories to linkage of ideals.

We define and give elementary properties of triangulated categories. We also give an application of triangulated categories to linkage theory in commutative algebra.

04-11-2019 Dilip Patil : IISc Bengaluru

Module of Kahler Differentials, smooth morphisms, Cohen Structure Theorems.

(During the week 03 Nov – 08 Nov, 2019) We continue to study smooth morphisms. The purpose of these two lectures is : (1) Definitions and Basic properties of the Module of Käher differentials. (2) Prove a criterion for when a quotient of a formally smooth algebra is again formally smooth. (3) Prove a characterisation of when a morphism is smooth called the J a c o b i a n c r i - t e r i o n. This is a preparation for the proof of Cohen’s structure theorem for complete local rings in the inequicharacteritic case.

First  Previous  1  2  3  4  5  6  7  8  9  10  11  12  13  14  15  16  17  18  19  20  Next  Last