Chennai Mathematical Institute
Seminars




Today's Seminar
  • 09-04-26
    Physics Seminar
    Time: 11:00 - 11:30 a.m. : pre-seminar
    11:30 - 11:45 a.m. : break
    11:45 - 01:00 p.m. : seminar
    Venue: NKN Hall
    Black Holes: Endgame
    Shoy Ouseph
    New York University Abu Dhabi.
    Abstract
    We discuss a pathway for complete evaporation of black holes in quantum JT with matter coupled to bath.


Today's Seminar
  • 09-04-26
    Mathematics-Physics Seminar
    Date: Thursday, 9 April 2026
    Time: 2.00 p.m.
    Venue: Lecture Hall 1
    Skein relations in Chern-Simons (continuation)
    Alexander Zakharov
    Chennai Mathematical Institute.
    Abstract
    Following Witten, we will show that non perturbative analysis of Chern-Simons in d=3 within Atiyah-Segal axiomatic approach to TQFT's, naturally leads to skein relations on Wilson correlators. Fix the level k. We will start with the gauge group U(1), where we recover Gauss integral formula for the linking number of a pair of knots in S^3 modulo k. Then we will turn to the non abelian case SU(N) to recover the value of Jones polynomial at the primitive (N+k)-root of unity.


Today's Seminar
  • 09-04-26
    Computer Science Faculty talk
    Date: Thursday, 9 April 2026
    Time: 3:30 - 4:10 p.m.
    Venue: Seminar Hall
    A Myhill-Nerode Characterization and Active Learning for One-clock Timed Automata
    B Srivathsan
    Chennai Mathematical Institute.
    Abstract
    The classical Myhill-Nerode theorem for regular languages provides two key insights: (1) L is regular iff its Nerode equivalence has a finite index, and (2) the automaton constructed from the Nerode equivalence is minimal among all DFAs for L. Automata learning algorithms rely on this theorem to provide theoretical guarantees.

    Extending such a theory to timed languages introduces significant challenges. For a start, the Nerode equivalence applied to timed words does not have finite index. This raises a natural question: for timed words, what is an alternative to the Nerode equivalence that leads to a canonical timed automaton?

    In this talk, we present a Myhill-Nerode style characterization for languages recognized by one-clock deterministic timed automata. The characterization is based on a new perspective to understand one-clock timed languages. Furthermore, the characterization leads to new active learning algorithms that learn canonical automata.

    Joint work with Kyveli Doveri and Pierre Ganty.


Today's Seminar
  • 09-04-26
    Computer Science Faculty talk
    Date: Thursday, 9 April 2026
    Time: 4:10 - 4:50 p.m.
    Venue: Seminar Hall
    Bounded Treewidth, Multiple Context-Free Languages, and Downward Closure
    Aiswarya Cyriac
    Chennai Mathematical Institute.
    Abstract
    We consider first-order structures with an underlying linear order (e.g., nested words) that have bounded treewidth and are definable in MSO. Such classes are very common in static analysis and verification of infinite-state systems (e.g., recursive programs and concurrent systems), as bounded treewidth is a powerful tool for reachability and related analyses. However, the word languages (i.e., action sequences corresponding to executions) of these systems remain poorly understood.

    We show that the word languages of MSO-definable bounded (special) treewidth systems are exactly the multiple context-free languages (MCFLs), a concept originating in computational linguistics. We also provide an optimal algorithm for computing their downward closures.

    This is joint work with Pascal Baumann, Prakash Saivasan, Lia Schutze, and Georg Zetzsche, which appeared in POPL 2026.


Forthcoming Seminars
  • 13-04-26
    Physics Seminar
    Time: 11:00-11:30 am: Pre-Seminar
    11:30-11:45 am: Break
    11:45-01:00 am: Seminar
    Venue: Lecture Hall 2
    Partha Paul
    Institute of Mathematical Sciences, Chennai.

Past Seminars (this year)
  • 08-04-26
    K. Lakshmanan Memorial Distinguished Lecture
    Date: Wednesday, 8 April 2026
    Time: 3:30 - 4.30 p.m.
    Venue: Seminar Hall
    Beyond Today's LLMs: With a Little Help from Neuroscience
    Anil Ananthaswamy
    Professor of Practice, Wadhwani School of AI, IIT Madras.

  • 08-04-26
    R.K. Rubugunday Distinguished Lecture
    Date: Wednesday, 8 April 2026
    Time: 2.00 - 3.00 p.m.
    Venue: Seminar Hall
    Cell-resolution imaging and mapping of whole human brains - When AI meets the Real "Neural Networks"
    Prof. Mohanasankar Sivaprakasam
    Dept. of Electrical Engineering, IIT Madras.

  • 02-04-26
    Mathematics-Physics Seminar
    Date: Thursday, 2 April 2026
    Time: 2.00 p.m.
    Venue: Lecture Hall 1
    Skein relations in Chern-Simons
    Alexander Zakharov
    Chennai Mathematical Institute.

  • 02-04-26
    Seminar Announcement
    Date: Thursday, 02 April 2026
    Time: 2.00 p.m.
    Venue: Seminar Hall
    Deterministic list decoding of Reed-Solomon codes
    Mrinal Kumar
    TIFR, Mumbai.

  • 02-04-26
    Computer Science Seminar
    Date: Thursday, 2 April 2026
    Time: 3.30 p.m.
    Venue: Seminar Hall
    Stability in Hospital Residents with sizes
    Girija Limaye
    BITS Pilani, Goa Campus.

  • 01-04-26
    Seminar Announcement
    Speaker: V Balaji, CMI
    Date: Wednesday, 1 April 2026
    Time: 3:30 p.m.
    Venue: Lecture Hall 5
    The Kena Upanishad, a glimpse into its Sadhana
    V Balaji
    Chennai Mathematical Institute.

  • 31-03-26
    Physics Seminar
    Date: Tuesday, 31 March 2026
    Time: 11.00 a.m.
    Venue: NKN Hall
    Nonlinear Dynamical Systems and Networks Part-2
    M. Lakshmanan
    Department of Nonlinear Dynamics, School of Physics, Bharathidasan University.

  • 31-03-26
    Computer Science Seminar
    Date: Tuesday, 31 March 2026
    Time: 11.50 a.m.
    Venue: Seminar Hall
    Degree Lower Bounds for Torus Polynomials and MAJORITY vs ACC0
    Vaibhav Krishan
    Institute of Mathematical Sciences, Chennai.

  • 30-03-26
    Physics Seminar
    Date: Monday, 30 March 2026
    Time: 11.00 - 11:30 am: pre-seminar
    11:30 - 11:45 am: break
    11:45 - 01:00 pm: seminar
    Venue: Lecture Hall 2
    Nonlinear Dynamical Systems and Networks
    M. Lakshmanan
    Department of Nonlinear Dynamics, School of Physics, Bharathidasan Universiy.

  • 26-03-26
    Computer Science Faculty talks
    Date: Thursday, 26 March 2026
    Time: 4:00 to 5:00 p.m.
    Venue: Seminar Hall, CMI
    Query-Reusable Proof Systems
    Varun Narayanan
    Chennai Mathematical Institute.

  • 26-03-26
    Mathematics-Physics Seminar
    Date: Thursday, 26 March 2026
    Time: 2.00 p.m.
    Venue: Lecture Hall 1
    Topological Quantum Field Theories
    Bhanu Kiran
    Chennai Mathematical Institute.

  • 24-03-26
    Seminar Announcement
    Date: Tuesday, 24 March 2026
    Time: 3.30 p.m.
    Venue: Seminar Hall
    On codimension-two subcanonical varieties in P^n
    Abhiram Subramanian
    Chennai Mathematical Institute.

  • 24-03-26
    Seminar Announcement
    Date: Tuesday, 24 March 2026
    Time: 11:50 a.m
    Venue: Seminar Hall
    Quantum-Classical Equivalence for AND-Functions
    Sreejata Kishore Bhattacharya
    TIFR, Mumbai.

  • 24-03-26
    Physics Seminar
    Date: Tuesday, 24 March 2026
    Time: 10.00 - 11.30 a.m.
    Venue: NKN Hall (lecture will be screened in online)
    Negative energies and the breakdown of bulk lengths in JT gravity
    Shreya Vardhan
    Caltech.

  • 23-03-26
    Mathematics-Computer Science Seminar
    Date: Monday, 23 March 2026
    Time: 11.50 a.m.
    Venue: Seminar Hall
    An Introduction to Automatic Sequences
    Anwesh Ray
    Chennai Mathematical Institute.

  • 20-03-26
    Chennai Combinatorics Colloquium Series
    Date: Friday, 20 March 2026
    Time: 3.30 p.m
    Venue: Seminar Hall
    Order in Chaos: Inevitable patterns in colored networks
    Narayanan N
    Department of Mathematics, IIT Madras.

  • 19-03-26
    CMI Arts Initiative Talk
    Date: Thursday, 19 March 2026
    Time: 3.30 p.m.
    Venue: Seminar Hall, CMI
    The Call of the Ghatam: A Lec-Dem
    Sumana Chandrashekar
    Female Ghatam Artiste and Researcher.

  • 27-03-26
    Commutative Algebra Seminar
    Date of lecture 1: Friday, 20 March 2026
    Date of lecture 2: Friday, 27 March 2026
    Time: 11.00 am to 12.00 p.m.
    Venue: LH803
    Commutative Algebra Seminar
    Abhiram Subramanian
    Chennai Mathematical Institute.

  • 19-03-26
    Mathematics-Physics Seminar
    Date: Thursday, 19 March 2026
    Time: 2.00 p.m.
    Venue: Lecture Hall 1
    Topological Quantum Field Theories
    Bhanu Kiran
    Chennai Mathematical Institute.

  • 19-03-26
    Computer Science Seminar
    Date: Thursday, 19 March 2026
    Time: 10.45 - 11.45 a.m.
    Venue: Seminar Hall
    Fair and Efficient Allocation of the Indivisibles
    Rohit Vaish
    IIT Delhi.

  • 16-03-26
    Mathmatics-Computer Science Seminar
    Date: Monday, 16 March 2026
    Time: 11:50 a.m.
    Venue: Seminar Hall
    An Introduction to Automatic Sequences
    Anwesh Ray
    Chennai Mathematical Institute.

  • 12-03-26
    Mathematics-Physics Seminar
    Date: Thursday, 12 March 2026
    Time: 2:00 p.m.
    Venue: Lecture Hall 202 (Hybrid mode)
    Topological quantum field theories
    Bhanu Kiran
    Chennai Mathematical Institute.

  • 12-03-26
    Seminar Announcement
    Date: Thursday, 12 March 2026
    Time: 3.30 p.m
    Venue: Lecture Hall 2
    Almost toric fibrations on K3 surfaces
    Pranav Vijay Chakravarthy
    Universite Libre de Bruxelles.

  • 09-03-26
    Physic Seminar
    Date: Monday, 9 March 2026
    Time:
    11.00-11.30 Pre-Seminar
    11.45-12.45 Main Seminar
    Venue: Lecture Hall 2
    Pre-Seminar: Stochastic Fluctuations in Relativistic Astrophysics
    Seema Satin
    IISER Kolkata.

  • 27-02-26
    Data Science Seminar
    Date: Friday, 27 February 2026
    Time: 12.00 - 1.00 p.m.
    Venue: NKN Hall
    Deep Signature Approach for McKean-Vlasov FBSDEs in a Random Environment
    Mathieu Lauriere
    Assistant Professor of Mathematics and Data Science, NYU Shanghai.

  • 25-02-26
    Computer Science Seminar
    Date: Wednesday, 25 February 2026
    Time: 2.30 p.m.
    Venue: Seminar Hall
    A New Loomis-Whitney-Type Projection Inequality
    Gowtham R. Kurri
    IIIT Hyderabad.

  • 23-02-26
    Physics Seminar
    Date: Monday, 23 February 2026
    The seminar will follow the usual format:
    11:00-11:30 a.m.: pre-seminar
    11:30-11:45 a.m.: tea/coffee
    11:45-1:00 p.m.: seminar
    Venue: Lecture Hall 6
    A New Cosmological Puzzle: Fast Radio Bursts and the Hubble Constant
    Surajit Kalita
    Astronomical Observatory, University of Warsaw.

  • 20-02-26
    Seminar Announcement
    Date: Friday, 20 February 2026
    Time: 3.30 - 4.45 p.m.
    Venue: Seminar Hall
    Elliptic Characteristic Classes and Hecke Algebra
    Andrzej Weber
    Mathematical Institute, University of Warsaw.

  • 16-02-26
    Talk Announcement
    Date: Monday, 16 February 2026
    Time: 3.30 p.m.
    Venue: Seminar Hall
    Diagnosis - a privilege of the laboratory in medical practice
    Dr. Raji Swamy


  • 16-02-26
    Physics Seminar
    Date: Monday, 16 February 2026
    The format of the talk is:
    Pre-seminar: 11.00-11.30am
    Coffee Break: 11.30-11.45am
    Main seminar: 11.45am-1.00pm
    Venue: Lecture Hall 6
    Doubly Separable Spacetimes and Symmetry Constraints on their Self-Gravitating Matter Content
    Prashant Kocherlakota
    Chennai Mathematical Institute.

  • 16-02-26
    Computer Science Seminar
    Date: Monday, 16 February 2026
    Time: 2.00 p.m.
    Venue: Seminar Hall
    A simple proof of Kamp's Theorem
    Paul Gastin
    LMF, ENS Paris-Saclay, France.

  • 20-02-26
    Lecture series announcement
    Date: 11, 18 and 20 February 2026
    Time: 9.10 - 10.30 a.m.
    Venue: LH801
    Proof of Zielonka's theorem through Propositional Dynamic Logic and Cascade products
    Paul Gastin
    LMF, ENS Paris-Saclay, France.

  • 10-02-26
    Lecture Series on Social Choice Theory
    Lectures 1 and 2: Tuesday, 3 February 2026, from 10:30 a.m. to 1:05 p.m.
    Lectures 3 and 4: Tuesday, 10 February 2026, from 10:30 a.m. to 1:05 p.m.
    Venue: Lecture Hall 801
    Lecture Series on Social Choice Theory
    Ori Livson
    University of Sydney.

  • 09-02-26
    Seminar Announcement
    Date: Monday, 9 February 2026
    Time: 3.30 p.m. to 4.30 p.m.
    Venue: Lecture Hall 3
    Condorcets Paradox as Non-Orientability
    Ori Livson
    University of Sydney, Australia.

  • 04-02-26
    Physics Seminar
    Date: Wednesday, 4 February 2026
    Time: 2.00 to 3.00 p.m.
    Venue: Lecture Hall 4
    Bayesian inference of neutron star equations of state and analysis of stellar oscillations
    Debanjan Guha Roy
    BITS Pilani, Hyderabad Campus.

  • 09-02-26
    Physics Seminar
    Date: Monday, 9 February 2026
    Time: 11.00 a.m. to 1.00 p.m.
    Venue: Lecture Hall 6
    The Geometrical Trinity of Gravity & Its Implications for Neutron Star Structure
    Sneha Pradhan
    BITS Pilani, Hyderabad.

  • 03-02-26
    Seminar Announcement
    Date: Tuesday, 3 February 2026
    Time: 2.00 to 3:30 p.m.
    Venue: Lecture Hall 1
    Group Order and Group Non-Membership is in QCMA
    Dhara Thakkar
    Graduate School of Mathematics, Nagoya University.

  • 06-02-26
    Seminar Announcement
    Date: Friday, 06 February 2026
    Time: 3.30 p.m.
    Venue: Seminar Hall
    q-opers, QQ-systems and Bethe Ansatz for spin chains
    Rahul Singh
    YMSC, Tsinghua University.

  • 02-02-26
    Lecture Announcement
    Date: Monday, 2 February 2026
    Time: 2.00 p.m.
    Venue: Seminar Hall
    On Proper Descent of Smooth Affine Surfaces with Finite Homotopy Rank-Sum
    Buddhadev Hajra
    ISI Kolkata.

  • 02-02-26
    Physics Seminar
    Date: Monday, 2 February 2026
    Venue: Lecture Hall 6
    Time: 11.00 a.m. to 1.00 p.m
    String Compactifications And Cosmological Solutions, GKP Geometric Moduli
    Ratul Mahanta
    USTC, Hefei.

  • 30-01-26
    Physics Seminar
    Date: Friday, 30 January 2026
    Time: 11:45 a.m.
    Venue: Seminar Hall
    LIGO-India and the future of Gravitational Wave Astronomy
    Sanjit Mitra
    IUCAA, Pune.

  • 28-01-26
    Seminar Announcement
    Date: Wednesday, 28 January 2026
    Time: 3.30 to 4.30 p.m.
    Venue: Seminar Hall
    Some early Ramsey type theorems and some applications
    S. D. Adhikari
    RKMVERI.

  • 04-02-26
    Lecture series announcement
    Dates: 27, 28, 30 January and 2 & 4 February 2026
    Time: 3.45 to 4.45 PM
    Venue: NKN Hall (hybrid mode)
    Mock modularity of Calabi-Yau threefolds and BPS black holes
    Sergey Alexandrov
    Laboratoire Charles Coulomb and University of Montpellier, CNRS, France.

  • 03-02-26
    Lecture series announcement
    The dates of his lectures are:
    Lectures 1 and 2 will be on January 16 at 3:30 p.m. Both talks will be 45 minutes long, with a short break.
    Lectures 3 and 4 will be on January 27 and 29 from 3:30 p.m. to 4.30 p.m.
    Lectures 5 and 6 will be on February 2 and 3 from 3:30 p.m. to 4.30 p.m.
    Venue: Seminar Hall, CMI (hybrid mode)
    Actions of finite group schemes
    Michel Brion
    Institut Fourier at the UniversitE Grenoble Alpes, France.

  • 23-01-26
    Physics Seminar
    Date: Friday, 23 January 2026
    Time: 10.30 a.m. to 11.30 a.m.
    Venue: Lecture Hall 6
    Emergent Higher-Spin Symmetry on the Celestial Sphere from Loop-Corrected Soft Photon Theorems
    Biswajit Sahoo
    Kings College, London.

  • 22-01-26
    Physics Seminar
    Date: Thursday, 22 January 2026
    Venue: Lecture Hall 2
    Time: 1.30 p.m to 2.45 p.m.
    Modeling the gravitational-wave memory for coalescing compact binaries
    Marc Favata
    Montclair State University, USA.

  • 16-01-26
    Data Science Seminar
    Date: Friday, 16 January 2026
    Time: 2:00 p.m.
    Venue: NKN Hall
    Small Language Models: Design, Fine-Tuning and Deployment
    Sudhir Kumar
    Coriolis Technologies.

  • 16-01-26
    Seminar Announcement
    Date: Friday, 16 January 2026
    Time: 11.45 a.m.
    Venue: Seminar Hall
    Class groups of Kummer extensions associated to CM Elliptic curves
    Arindam Bhattacharya
    University of Massachusetts, Amherst.

  • 16-01-26
    Seminar Announcement
    Date: Friday, 16 January 2026
    Time: 11.45 a.m
    Venue: Lecture Hall 1
    A new characterization of VNP via Colored Determinant
    Prasad Chaugule
    IIT Delhi.

  • 13-01-26
    Seminar Announcement
    Date: Tuesday, 13 January 2026
    Time: 12:00 p.m
    Venue: Lecture Hall 4
    On the relative power of reduction notions in different characteristics
    Prasad Chaugule
    IIT Delhi.

  • 13-01-26
    Physics Seminar
    Date: Tuesday, 13 January 2026
    Time: 3:45 p.m.
    Venue: Lecture Hall 6
    Mock Modular forms and Vafa Witten Theory
    Aradhita Chattopadhyaya
    Chennai Mathematical Institute.

  • 12-01-26
    Physics Seminar
    Date: Monday, 12 January 2026
    Time: 3:45 p.m.
    Venue: Lecture Hall 6
    Mock Modular forms and Vafa Witten Theory
    Aradhita Chattopadhyaya
    Chennai Mathematical Institute.

  • 12-01-26
    Physics Seminar
    Date: Monday, 12 January 2026
    Time: 11.00 am to 1.00 p.m.
    Venue: Lecture Hall 6
    Boundary Energy-Momentum Tensors for Asymptotically Flat Spacetimes
    Vijay Nenmeli
    University of Edinburgh.

  • 09-01-26
    Computer Science Seminar
    Date: Friday, 9 January 2026
    Time: 2.00 - 3.15 p.m.
    Venue: Seminar Hall
    The complexity of the factors of polynomials
    Somnath Bhattacharjee
    University of Toronto.

  • 07-01-26
    Lecture Announcement
    Date: Wednesday, 7 January 2026
    Time: 4:00 p.m. - 4:30 p.m.
    Venue: Seminar Hall
    A Torelli type theorem for elliptic curves
    Tomasz Szemberg
    University of the National Education Commission, Krakow, Poland.

  • 07-01-26
    Lecture Announcement
    Date: Wednesday, 7 January 2026
    Time: 3:30 - 4:00 p.m.
    Venue: Seminar Hall
    Configurations of points in projective space and their projections
    Justyna Szpond
    University of the National Education Commission, Krakow, Poland.

  • 06-01-26
    Seminar Announcement
    Date: Tuesday, 6 January 2026
    Time: 2.00 to 3.30 p.m.
    Venue: Seminar Hall
    Redundancy is all you need (for CSP sparsification)
    Venkatesan Guruswami
    UC Berkeley and Simons Institute.

  • 05-01-26
    Seminar Announcement
    Date: Monday, 5 January 2026
    Time: 2.00 to 3.30 p.m.
    Venue: Seminar Hall
    Optimal Proximity Gaps for Subspace-Design Codes and (Random) Reed-Solomon Code\ s
    Rohan Goyal
    MIT.

  • 05-01-26
    Mathematics Seminar
    Date: Monday, 5 January 2026
    Time: 3.30 to 4.30 p.m.
    Venue: Seminar Hall
    The inverse system of Gorenstein points
    Maria Evelina Rossi
    University of Genoa.