July 2022
Public Access Category: All |

- Time:
- 11:30am - 12:30pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
Speaker Name: Sridhar Narayan

Titile:"The weighted perfect matching association scheme"

Venue: Ramanujan Hall

- Time:
- 3:00pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
Samir Shukla (IIT Mandi) will be speaking on Vietoris-Rips Complexes of hypercube graphs in Topology and Combinatorics Seminar on Tuesday, 5th July 2022 at 3 PM in Ramanujan Hall. Please find the abstract attached.

http://www.math.iitb.ac.in/~seminar/combinatorics/Samir_Shukla.pdf

- Time:
- 3:00pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
Anurag Singh (IIT Bhillai ) will be speaking on Homomorphisms complexes, reconfiguration, and homotopy for directed graphs in Topology and Combinatorics Seminar on Thursday, 7th July 2022 at 3 PM in Ramanujan Hall. Please find the abstract attached.

http://www.math.iitb.ac.in/~seminar/combinatorics/Abstract_Anurag.pdf

- Time:
- 4:00pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
Department Colloquium Speaker: Sarbeswar Pal, IISER Trivandrum Friday 15 July 4 pm Venue Ramanujan Hall Title: On a conjecture of Drinfeld. Abstract: Let C be a smooth irreducible projective curve of genus g ≥ 4. Let MC(r, δ) be moduli space of stable vector bundles on C of rank r and fixed determinant δ of degree d. Then the locus of wobbly bundles is known to be closed in MC(r, δ). Drinfeld has conjectured that the wobbly locus is pure of co-dimension one, i.e. it is a divisor in MC(r, δ). In this talk, we will give proof of the conjecture when (r, d) = 1

- Time:
- 4:00pm - 5:00pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
**Interplay between extreme value theory and geometry/dynamics**

**Abstract**

Mathematics is a wonderful synergy between various branches with beautiful connections that link them in an elegant fashion. In this series of three lectures, we will discuss how probability theory (more specifically, extreme value theory) can benefit from ergodic theory and hyperbolic geometry, and vice versa.

**The first lecture (on 20th July)**would concentrate on extreme value theory for continued fractions and Gauss dynamical system. In this case, we shall use probabilistic tools, which will have ergodic theoretic, number theoretic and geometric consequences.

On the other hand, in the**second and third lectures (on 21st and 22nd July, respectively)**, we will focus on extremes of stationary symmetric stable random fields. In this context, we shall discuss how nonsingular dynamics (especially for boundary actions arising in hyperbolic geometry) can give rise to probabilistic results for stationary stable fields.

These lectures will be based on a series of joint work with Anish Ghosh (TIFR Mumbai), Maxim Kirsebom (Univ of Hamburg), Mahan Mj (TIFR Mumbai), Gennady Samorodnitsky (Cornell Univ) and Sourav Sarkar (Univ of Cambridge) carried out at different points of time. Special care will be taken so that everyone can follow these lectures.

- Time:
- 4:00pm - 5:00pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
**Interplay between extreme value theory and geometry/dynamics**

**Abstract**

Mathematics is a wonderful synergy between various branches with beautiful connections that link them in an elegant fashion. In this series of three lectures, we will discuss how probability theory (more specifically, extreme value theory) can benefit from ergodic theory and hyperbolic geometry, and vice versa.

**The first lecture (on 20th July)**would concentrate on extreme value theory for continued fractions and Gauss dynamical system. In this case, we shall use probabilistic tools, which will have ergodic theoretic, number theoretic and geometric consequences.

On the other hand, in the**second and third lectures (on 21st and 22nd July, respectively)**, we will focus on extremes of stationary symmetric stable random fields. In this context, we shall discuss how nonsingular dynamics (especially for boundary actions arising in hyperbolic geometry) can give rise to probabilistic results for stationary stable fields.

These lectures will be based on a series of joint work with Anish Ghosh (TIFR Mumbai), Maxim Kirsebom (Univ of Hamburg), Mahan Mj (TIFR Mumbai), Gennady Samorodnitsky (Cornell Univ) and Sourav Sarkar (Univ of Cambridge) carried out at different points of time. Special care will be taken so that everyone can follow these lectures.

- Time:
- 4:00pm - 5:00pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
**Interplay between extreme value theory and geometry/dynamics**

**Abstract**

Mathematics is a wonderful synergy between various branches with beautiful connections that link them in an elegant fashion. In this series of three lectures, we will discuss how probability theory (more specifically, extreme value theory) can benefit from ergodic theory and hyperbolic geometry, and vice versa.

**The first lecture (on 20th July)**would concentrate on extreme value theory for continued fractions and Gauss dynamical system. In this case, we shall use probabilistic tools, which will have ergodic theoretic, number theoretic and geometric consequences.

On the other hand, in the**second and third lectures (on 21st and 22nd July, respectively)**, we will focus on extremes of stationary symmetric stable random fields. In this context, we shall discuss how nonsingular dynamics (especially for boundary actions arising in hyperbolic geometry) can give rise to probabilistic results for stationary stable fields.

These lectures will be based on a series of joint work with Anish Ghosh (TIFR Mumbai), Maxim Kirsebom (Univ of Hamburg), Mahan Mj (TIFR Mumbai), Gennady Samorodnitsky (Cornell Univ) and Sourav Sarkar (Univ of Cambridge) carried out at different points of time. Special care will be taken so that everyone can follow these lectures.

- Time:
- 2:00pm - 3:30pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
DDT: Tuesday, 26th July, 2:00 – 3:30 pm

Venue : Ramanujan Hall, Department of mathematics.

Title: Okounkov-Vershik approach to the representation theory of symmetric

groups.

Abstract: In this series of talks we will bootstrap the representation

theory of symmetric groups inductively, following the 2005 revision of

Vershik's and Okounkov's seminal paper on the topic.

We have now a dedicated website where one can find the notes and resources

from the past meets and announcements of the upcoming meetings:

https://sites.google.com/view/rtag/

- Time:
- 4:30pm - 6:00pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
Title: p-adic Hodge Theory and Combinatorics.

Speaker: Som Phene, University of Michigan.

Time: Tuesday, 26 July, 4:30 pm.

Venue: ***Ramanujan Hall***

Abstract: We introduce combinatorial geometries and geometric lattices. We show an equivalence between them followed by the correspondence of their finite versions with simple matroids. We then introduce the characteristic polynomial of a matroid, the Mobius algebra of a lattice. We hope to shed light on the result of log concavity for simple matroids (Huh 2012 for matroids representable in char 0, Huh-Katz 2012 for each representable matroid, Adiprasito-Huh-Katz 2018 for general matroids).

- Time:
- 10:30am - 11:30am
- Location:
- Video call link: https://meet.google.com/mkf-auok-inr
- Description:
Speaker: Shankar TR

Title: Commuting isometries and contractions

Abstract: In this talk, I will discuss defect operators associated with

pure pairs of commuting isometries and related results. I will demonstrate

how defect operators can be used to characterize certain submodules of the

Hardy space over the bi-disc. Finally, I will present some example of

quotient modules of the Hardy space over the poly-disc where bounded

lifting holds.

Date and Time: Wednesday, July 27· 10:30am – 11:30 am

Google Meet joining info

Video call link: https://meet.google.com/mkf-auok-inr

- Time:
- 4:30pm
- Location:
- Room No 215, Department of Mathematics
- Description:
Title: p-adic Hodge Theory and Combinatorics-II Speaker: Som Phene, University of Michigan. Time: Tuesday, 28 July, 4:30 pm. Venue: Room 215 Abstract: We introduce combinatorial geometries and geometric lattices. We show an equivalence between them followed by the correspondence of their finite versions with simple matroids. We then introduce the characteristic polynomial of a matroid, the Mobius algebra of a lattice. We hope to shed light on the result of log concavity for simple matroids (Huh 2012 for matroids representable in char 0, Huh-Katz 2012 for each representable matroid, Adiprasito-Huh-Katz 2018 for general matroids).

- Time:
- 4:00pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
Speaker: Shaunak Deo, IISc Bangalore Time & Date: 4 pm, Friday, 29 July 2022 Venue: Ramanujan Hall Title: The Eisenstein ideal of weight $k$ and ranks of Hecke algebras Abstract: Let $p$ and $\ell$ be primes such that $p > 3$ and $p \mid \ell-1$ and $k$ be an even integer. Using deformation theory of Galois representations, we will give a necessary and sufficient condition for the $Z_p$-rank of the completion of the Hecke algebra acting on the space of cuspidal modular forms of weight $k$ and level $\Gamma_0(\ell)$ at the maximal Eisenstein ideal containing $p$ to be greater than $1$ in terms of vanishing of the cup products of certain global Galois cohomology classes.