- Time:
- 11:30am
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
Seminar on quantum groups and C*-algebras Monday, 16 October 2023, 11:30 am ================================ Venue: Ramanujan hall Host: Saikat Mazumdar Speaker: Dr. Sutanu Roy Affiliation: NISER Bhubaneswar Title: Braided quantum groups and quantum symmetries in the C*-algebraic framework Abstract: Compact quantum groups naturally generalize compact groups in the realm of noncommutative geometry. They also appear as symmetries of various (classical and quantum) spaces. However, while investigating the semidirect product of compact quantum groups, a more general concept, namely braided compact quantum groups, emerges quite naturally. In this talk, I will provide motivation for braided compact quantum groups and illustrate them with examples. Following that, I will present recent developments in the relationship between braided compact quantum groups and quantum symmetries of spaces (of certain types). If time permits, I shall mention certain aspects of the general theory of locally compact braided quantum groups within the C*-algebraic framework.

- Time:
- 4:00pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
Ph.D. defense seminar Monday, 16th October, 4 pm ============================= Host: Siuli Mukhopadhyay Venue: Ramanujan Hall Speaker: Savita Pareek Title: On Some Problems in Mixed-effect Models

- Time:
- 2:30pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
Topology and Related Topics Seminar Tuesday, 17 October 2023, 2:30 pm ======================== Venue: Ramanujan hall Host: Rekha Santhanam Speaker: Navnath Daundkar Affiliation: IIT Bombay Title: Cohomology of moment angle complexes - II Abstract: This talk is a continuation of the previous session on "Cohomology of moment angle complexes." We will present a cellular structure on a moment angle complex associated with a simplicial complex $K$ and prove that the corresponding cellular cochain algebra is a quotient of the Koszul algebra of the Stanley-Reisner ring of $K$.

- Time:
- 3:30pm-4:45pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
Commutative Algebra seminar Tuesday, 17 Oct. 3.30-4.45 pm ============================ Venue: Ramanujan Hall Host: Tony Puthenpurakal Speaker: Jugal Verma, IIT Bombay Title: The Grothendieck-Serre formula for Hilbert functions Abstract: We will prove the Grothendieck-Serre formula for Hilbert functions of finite graded modules over graded Noetherian rings.

- Time:
- 4:00pm-5:00pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
Mathematics Colloquium Wednesday, 18 October, 4-5 pm =================== Venue: Ramanujan Hall Host: Sudhir R Ghorpade Speaker: Trygve Johnsen, Affiliation: The Arctic University of Norway Title: Various types of codes and matroids Abstract: The talk will be about the general principles of error-correcting codes and various ways of defining such codes mathematically. We will see how some important properties, but not all properties, of the codes, are determined by certain combinatorial structures (matroids, q-matroids, etc.) associated with them.

- Time:
- 10:00am
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
Algebraic geometry seminar Wednesday, 19th October, 10 am ====================== Venue: Ramanujan Hall Host: Sudarshan Gurjar Speaker: Sourav Das Affiliation: Chennai Mathematical Institute Title: Moduli problems on nodal curves Abstract: In this talk, I will mainly discuss the moduli of Higgs bundles on nodal curves. First, I will talk about degenerations and briefly overview a few moduli problems on a nodal curve, e.g., Picard, moduli of vector bundles. Then, I will discuss a semi-stable degeneration of the moduli of Higgs bundles and the extension of Hitchin's symplectic form to this degeneration. If time permits, I will discuss a few possible applications of this study.

- Time:
- 11:30am-1:00pm
- Description:
Lecture series on Hodge Theory Thursday, 12 Oct. 11.30-1.00 and 3.30-4.30 pm ====================== Venue: Ramanujan Hall Host: Sudarshan Gurjar Speaker: V. Srinivas, IIT Bombay Title: Kahler condition and its consequences Abstract: We review the basics of spectral sequences, and then discuss the ``Hodge to de Rham'' spectral sequence.

- Time:
- 2:30pm
- Location:
- Room No 215, Department of Mathematics
- Description:
Topology and Related Topics Seminar Thursday, 19 October 2023, 2:30 pm ========================= Venue: Room 215 Host: Rekha Santhanam Speaker: Shuchita Goyal Affiliation: Krea University Title: Grid graphs and their independence complexes Abstract: A matching in a graph G is a collection of disjoint edges. The matching complex of a graph G is a simplicial complex whose simplices are matchings in G. Lately, grid graphs have been studied for their homological and homotopical structures. In this talk, we will focus on the grid graphs whose each block is a square. In particular, we will see that the matching complexes of 3n grid graphs are homotopy equivalent to a wedge of spheres. We will also see the comprehensive list of the dimensions of spheres appearing in the wedge.

- Time:
- 3:30pm-4:30pm
- Description:
Lecture series on Hodge Theory Thursday, 12 Oct. 11.30-1.00 and 3.30-4.30 pm ====================== Venue: Ramanujan Hall Host: Sudarshan Gurjar Speaker: V. Srinivas, IIT Bombay Title: Kahler condition and its consequences Abstract: We review the basics of spectral sequences, and then discuss the ``Hodge to de Rham'' spectral sequence.

- Time:
- 5:15pm-6:15pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
Analysis and PDE seminar Thursday, 19th Oct, 5:15 pm - 6:15 pm ========================= Venue: Ramanujan Hall Host: Chandan Biswas Speaker: Chandan Biswas, IIT Bombay Title: A basic introduction to Fourier restriction estimates Abstract: This is the third talk of the series. We will finish our discussion on Hausdorff-Young inequality, and start on restrictions on the parabola in dimension 2 and the moment curve in higher dimensions.

- Time:
- 11:30am
- Description:
Lecture series on algebraic stacks

Friday 20 October, 11.30 am========================

Venue: Ramanujan Hall

Host: Sudarshan GurjarSpeaker: Nitin Nitsure

Affiliation: TIFR, Mumbai (Retd)

Title: Examples of Algebraic Stacks

Abstract: This lecture will present various basic examples and

non-examples of algebraic stacks. These examples are useful in

applications, and they also serve to better understand the definitions

- Time:
- 4:00pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
Mathematics Colloquium Friday, 20 Oct. 4 pm ==================== Venue: Ramanujan Hall Host: Ravi Raghunathan Speaker: Dinakar Ramakrishnan Affiliation: California Institute of Technology Title: Abelian 3-folds of Picard type, and a uniform irreducibility result Abstract: Half a century ago Manin proved a uniform boundedness result for the p-power torsion of any non-CM elliptic curve E over a given number field k. A few years ago, Cadoret and Tamagawa established a similar result for the p-adic representations attached to 1-dimensional abelian families. In joint work with M. Dimitrov, we provide the 1st evidence in higher dimension, for families of abelian 3-folds parametrized by certain Picard modular _surfaces_. The proof also involves aspects of (global and local) representation theory.

- Time:
- 5:15pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
Coding Theory Seminar

Friday, 20th Oct., 5.15 pm

===================

Venue: Ramanujan Hall

Host: Sudhir Ghorpade

Speaker: Prof. Trygve Johnsen

Affiliation: Arctic University of Norway=

Title: Homological and combinatorial invariants of rank-metric codes

Abstract: We will look at some similarities and differences between the

behavior of (traditional) linear codes with the Hamming distance, and

Gabidulin rank metric codes. We will study how methods for determining

the spectra and invariants of traditional codes can, or cannot, be

"transferred" to studying analogous properties of the rank-metric codes.