The Journal Club

For Theoretical Physics and Mathematics
If you are not a part of this group and wish to give a club talk, please write to nexustheoretical@gmail.com

Upcoming Club Talks 

• Devang Bajpai - Eigenvectors from eigenvalues: A survey of a basic identity in linear algebra (Date - NA)
  Abstract  -  arXiv:1908.03795v4, Prerequisites: Working Knowledge of Linear Algebra.
  Venue & Timing - Mathematics Lab, Ground Floor, SBS

Previous Talks 

• Devang Bajpai - Introduction to Black Holes (Date - 21 Feb`26)
  Abstract  -  In this talk, we will talk about Black Holes, Entropy, and the generalized second law for black holes, Von Neumann Entropy, and Page Curve.
  Venue & Timing - L2 & 10:00 AM

• Saraswata Sensarma - An introduction to the spectral theory of random matrices (Date - 12 Feb`26) Jointly organized with SL2Z Club
  Abstract  -Random matrices are amongst the most ubiquitous and versatile models of probability theory. Pioneered by Wishart (in the context of covariance matrix estimation in statistics) and Wigner (as a model of the Hamiltonian for atomic nuclei), this model has found a variety of applications to problems in probability theory, statistical mechanics, mathematical physics, and even number theory. In this talk, we'll discuss the spectral properties of various classes of random matrices, which turn out to be remarkably universal. This makes random matrices particularly well-suited towards estimation and prediction in various contexts. In particular, we will discuss the limiting spectral distributions of various Hermitian and non-Hermitian matrix ensembles (the semicircle law and its generalisations, and circular law. We will also go over various properties of eigenvectors (in partcular, delocalisation) for these models. References: The discussion will be expository in nature. The part on the semicircle law and circular law can be found in the books on Random Matrix Theory by Tao and by Anderson-Guionnet-Zeitouni. An introduction to eigenvector delocalisation is provided in the book A dynamical approach to random matrix theory by Erdos and Yau.
  Venue & Timing - Online, Zoom, 08:30 PM IST (2030hrs IST)

• Aayush Verma - A Crash Talk on Tannaka Duality (Date - 24 Dec`25) Winter Club
  Abstract  - I will introduce the idea of duality, in particular context of compact groups first and later build to non-compact cases. In essence, alongside, I will try to convey the feelings of dualities in mathematics and physics. 
  Venue & Timing - Online, Zoom, 03:30 PM IST (1530hrs IST)

• Special Seminar by Prof. V. K. Murty (Director, LMSI and University of Toronto) - From Euler to Grothendieck: Zeta(3), Log2, Pi jointly organized with Dept. of Mathematics, IITK. (Date - 17 Oct`25)

• Dr. Arpit Dwivedi (Department of Mathematics, CSJMU) - Matrix Multiplication: A Play of Perspectives (Date - 19 Mar`25)
  Abstract  -  I will show you five ways of multiplying matrices and show you how one of them is really useful and insightful.
  Venue & Timing - Room No 209, SBS, 02:30 PM IST (1430hrs IST)
  (Slides)

• Dr. Arpit Dwivedi (Department of Mathematics, CSJMU) - The graph of the Gamma function (Date - 26 Oct`24)
  Abstract  -  In this talk, I intend to take you on a trek of collecting the gems from the mathematical side quests which are necessary to reach to our main quest which is having an idea about the shape of the graph of the Gamma function.
  Venue & Timing - Mathematics Lab, Ground Floor, SBS, 11 AM IST (1100hrs IST)
  (Recording)

• Vaibhav Kalvakota - The Essence of LLMs and Transformers (Date - 28 Sept'24)
  Abstract  -  We will talk about adaptive sparsity in Transformers and the general contextualization of LLMs into computationally efficient models. Prerequisites: 1706.03762 and 1909.00015.
  Venue & Timing - Online, 6PM IST (1800hrs IST)
  (Recording - Slides)