Date: Oct 31, 2025
Title: The Infinitude of Primes: An Exploration of Proofs.
Abstract: Whenever we look for famous open problems in number theory, there’s a high chance that primes are involved. In this talk, we revisit the foundational fact without which these problems wouldn’t even make sense — that there are infinitely many primes. First proved by Euclid long ago, this simple result encodes surprisingly beautiful and deep ideas. We will explore a few elegant proofs of this timeless theorem.
Date: Oct 24, 2025
Title: Ramanujan’s Tau Function and Its Conjectures.
Abstract: In this talk, we will give a brief introduction to the basic notations and concepts related to Modular Forms. We will then introduce Ramanujan’s tau-function, which first appeared in his celebrated 1916 paper. We will present the three famous conjectures proposed by Ramanujan concerning the tau-function, together with some historical remarks. The proofs of the first two conjectures will be outlined using the theory of Modular Forms and Hecke operators, while a weaker bound toward the third conjecture will be presented via Dirichlet series attached to Modular Forms.
Date: Oct 17, 2025
Title: The Geometry of Division in a Ring.
Abstract: Division with remainder, familiar from the integers, can be extended to more general rings through the notion of Euclidean domains. In this talk, we explore how the geometry of “size” functions guides the existence of such division processes. We will discuss structural tools such as universal side divisors and Motzkin’s criterion, which provide powerful ways to recognize when a ring is Euclidean. Along the way, applications to algebraic number theory, factorization, and computational methods in cryptography will be highlighted.
Date: Sep 12, 2025
Title: Jordan Curve Theorem.
Abstract: In mathematics, problems that appear simple to state are often surprisingly difficult to prove. A classic example is the Jordan curve theorem, which asserts that any simple closed curve (a continuous, non-self-intersecting loop) in the plane divides the plane into exactly two connected regions: an "inside" and an "outside." While this fact is visually intuitive- especially when we picture a circle or something close to it-the rigorous proof is far from trivial. The Jordan curve theorem forms the foundation for algorithms that determine whether a point lies inside or outside a closed region, a concept central to applications ranging from computer graphics to geographical information systems. The goal of this talk is to present and discuss a rigorous proof of this subtle but fundamental topological result.
Date: Aug 29, 2025
Title: Semigroup theory and its application to parabolic PDEs.
Abstract: In this talk, I will begin with an overview of semigroup theory, the variation-of-constant formula, Sobolev spaces, the maximum principle and weak solutions. Building on these preliminaries, I will then apply these concepts to establish the existence of solutions to a perturbed heat equation.
Date: Aug 13, 2025
Title: Multi-zeta values, their Q-Algebra and Modular forms.
Abstract: This talk will be expository in nature. We first define the multi-zeta values (MZVs) and their Q-Algebra structure. We will then discuss the Shuffle and Stuffle relations satisfied by the MZVs. We will discuss the Eichler-Shimura isomorphism between Cusp forms and Period polynomials. We will discuss a few conjectures on the Q-Algebra, and its connections with the mixed Tate motives if time permits. The content of the talk is mainly based on the works of Zagier, Gangl-Kaneko-Zagier and Francis Brown. This talk will be built on basic concepts in algebra and analytic number theory.
Date: Apr 8, 2025
Title: Primes Numbers are supernatural
Abstract: Fermat conjectured that 2^(2^n) + 1 is prime for every natural number n, but Euler disproved this by showing that it fails for n=5. This leads to a broader question: does there exist a function of natural numbers, constructed using a variable n, a finite set of constants, and the operations of addition, multiplication, and exponentiation, that always yields prime values? It is conjectured that no such function exists. In this talk, we will explore the formalization of this conjecture and its implications.
Date: Mar 18, 2025
Title: Artin's conjecture and its Hooley's grail
Abstract: Why does the decimal expansion of 1/7 repeat every 6 digits, while 1/98007599 in base 2 cycles after about 50 million digits? These patterns, hidden in the arithmetic of reciprocals, hint at a deeper mystery: the behavior of multiplicative orders modulo prime numbers. In 1927, Emil Artin proposed that for infinitely many primes p, some fixed integer a (as long as it's not 1, -1 or a perfect square) generates the group (Z/pZ)*.
In this talk, we will look at a flawed probabilistic argument to conjecture the density constant for such primes and see how Artin arrived at the same constant through purely algebraic methods. We shall then see how Lehmer found a mistake in Artin's argument and modified it to obtain the right constant. Finally, we will state Hooley’s breakthrough conditional result and some recent unconditional results which take us a step closer towards proving Artin's conjecture in its full glory.
Date: Feb 25, 2025
Title: Theory of Cauchy Principal Value Integrals
Abstract: In this talk, we are going to discuss the definition and develop a few results of the Cauchy principal value integrals. We will mainly be discussing the work of Hardy, who said that, "Definite integrals are of two kinds—finite and infinite. In finite integrals the range of integration is finite, and the subject of integration finite throughout it..." We shall study the integrals of the second kind. This talk will be built on basic concepts in real analysis.
Date: Feb 11, 2025
Title: An Introduction to Exterior Algebra
Abstract: In this seminar talk, we will revisit the exterior algebra of a real vector space V. This is a graded algebra containing V equipped with a product, called exterior product or wedge product such that v ∧ v = 0, for all v ∈ V. The wedge product was originally introduced as an algebraic construction used in geometry to study areas and volumes.
Date: Feb 4, 2025
Title: Introduction to Huber rings
Abstract: If a ring is endowed with a topology that behaves well with its algebraic structures (i.e., the ring operations are continuous), many interesting properties emerge. Roland Huber introduced a class of topological rings, namely Huber rings, which generalize the notions of Tate rings and adic rings defined by ideals (I-adic topologies on commutative rings). The main focus of the talk is to discuss a few sections of the seminal paper 'Continuous Valuations' by Huber himself, and if time permits, we will construct adic spaces—a category that encompasses many well-known algebraic geometric objects like rigid analytic spaces, formal schemes and schemes.
Date: Jan 28, 2025
Title: A brief introduction to transcendental numbers
Abstract: Numbers are among the first mathematical objects that we encounter in daily life. They are very basic yet mysterious in nature. In this talk, we will discuss one such mystery known as transcendental numbers. We will discuss some basic theorems related to transcendental numbers and their applications. We will also discuss some known results and open problems.
Date: Jan 21, 2025
Title: Explicit zero free region of the Riemann Zeta function
Abstract: We will discuss the proof that the Riemann zeta function has no zeros in the region Re(s) ≥ 1 − 1/(55.241 (log |t|)2/3 (log log |t|)1/3) for |t| ≥ 3. We will also discuss the intermediate zero-free region.
Date: Nov 12, 2024
Title: Introduction to Quiver Representation
Abstract: A quiver is a simple mathematical object: a directed graph. A representation of a quiver assigns a vector space to each vertex and a linear map to each arrow. We will see an equivalence between the category of quiver representation and the category of modules over path algebras.
Date: Oct 29, 2024
Title: Differential Nullstellensutz
Abstract: This talk is an attempt to lead a peek into the world of Differential Algebra. As the name suggests, we will be drawing a lot of inspiration from commutative algebra and will be seeing a lot of similar results but in a differential algebraic setting (will define what that means as well). A course in commutative algebra is, of course, not a pre-requisite to the talk, but you can connect things if you know a couple of results. We will start by defining what a derivation is in general and try to see various algebraic ways to play around with it. The talk won’t contain much of the proves but will try to motivate most of the results with some nice examples and intuitions.
Date: Oct 15, 2024
Title: Eternal Vertex Cover
Abstract: In this talk, we will discuss a two-player game played on a graph. We will relate the winning strategies of the game to some structural parameters of the graph, such as vertex cover. We will not assume any pre-requisites about graph theory, algorithms or complexity.
Date: Sep 17, 2024
Title: A Quick Overview of de Rham Cohomology
Abstract: Recall that given a smooth manifold M, there is a unique exterior derivative d on M. A differential form ω on M is called closed if dω = 0, and it is called exact if ω = dη, for some differential form η on M. Since d∘d = 0, every exact form is also a closed form, not conversely. But how can one find the extent to which a closed form is not exact? It turns out that whether every closed form on a manifold is exact depends on the topology of the manifold. This notion is given by the de Rham Cohomology of the manifold. In this talk, I shall define the de Rham Cohomology of a smooth manifold as the extent to which closed forms on a manifold are not exact. I shall discuss some of the basic examples to compute de Rham Cohomology. Also, I shall show that the de Rham Cohomology, possibly, one of the most important diffeomorphism invariants of a manifold.
Date: Sep 10, 2024
Title: On the connection between partitions and divisor functions
Abstract: The well-known divisor function d(n) plays an important role in number theory, whereas partitions of a number are one of the central themes in additive number theory. In 1981, K. Uchimura derived an identity for a divisor-generating function using sorting theory. In 1984, D.M. Bressoud and M.V. Subbarao gave a combinatorial proof of uchimura's result in terms of partitions of n and generalized it. In this talk, we will see the proof presented in their paper and equivalent q-series identities.
Date: Aug 27, 2024
Title: Maximality and Prime Ideals
Abstract: Given an abelian category, we know that we can construct the homotopy category of chain complexes. In this talk, I will be showing the existence of a category, namely the derived category, to which there is a functor from the homotopy category which takes quasi isomorphisms (isomorphism in the homology level) to isomorphisms in the derived category, and it is universal with respect to this property. Having said these technical jargons, we will make it again complicated by introducing these techniques to algebraic geometry, specifically in the study of algebraic varieties and its classification.
Date: Aug 13, 2024
Title: Maximality and Prime Ideals
Abstract: A standard result we learn in basic ring theory is that given any ring with unity, every two-sided maximal ideal is prime. Over time, mathematicians realized that this fact is one of the consequences of striking simple theorems concerning the maximality condition and the primality of an ideal. In this talk, we will look at some of these simple yet beautiful theorems and see how they make life easy in rings.
Date: Apr 23, 2024
Title: Colon Structure of Associated Primes of Monomial Ideals
Abstract: In commutative algebra, the associated primes of the quotient ring serve as an essential tool to understand various algebraic properties of the ring. The associated primes can also be viewed as colon ideal (also known as ideal quotients). This talk will focus on the associated primes of monomial ideals. We will explicitly express the associated primes as a colon ideal for monomial ideals. We will see how this expression aligns with the combinatorial properties of graphs in the case of edge ideals.
Date: Apr 9, 2024
Title: The codification of poetry and the birth of combinatorics.
Abstract: Historically, mathematics has developed through different branches. One of the most important and interesting among them is combinatorics. Interestingly, the development of combinatorics in ancient India is closely related to the codification of poetry. In this talk, we will give a brief introduction to Indian classical poetry. Then, we will explore the interesting mathematics arising from it, providing examples from Pingala's Chandashastra.
Date: Mar 19, 2024
Title: Group Action and Orientation
Abstract: In the last talk, we defined all the prerequisites ( such as the orientation of a smooth manifold and its equivalent conditions, the smooth action of a group on a smooth manifold, etc.). In this talk, we will continue from the smooth action of a group on a smooth manifold. Firstly, we will see that the resultant orbit space M/G of a smooth action of a group G on a smooth manifold M admits a smooth structure so that the quotient map π: M → M/G is a local diffeomorphism. We will then discuss that if M is oriented, so is the orbit space M/G, and vice versa. Finally, as examples, we will discuss the orientability of the real-projective space, the Möbius strip, and the Klein bottle.
Date: Mar 19, 2024
Title: Group Action and Orientation
Abstract: In the last talk, we defined all the prerequisites (such as the orientation of a smooth manifold and its equivalent conditions, the smooth action of a group on a smooth manifold, etc.). In this talk, we will continue from the smooth action of a group on a smooth manifold. Firstly, we will see that the resultant orbit space M/G of a smooth action of a group G on a smooth manifold M admits a smooth structure so that the quotient map π: M → M/G is a local diffeomorphism. We will then discuss that if M is oriented, so is the orbit space M/G, and vice versa. Finally, as examples, we will discuss the orientability of the real-projective space, the Möbius strip, and the Klein bottle.
Date: Feb 13, 2024
Title: Sieve of Eratosthenes and its applications
Abstract: Sieve methods are powerful tools to solve many number theoretic problems. In this talk, we will first discuss the classical sieve of Eratosthenes, which gives an algorithmic method to find primes until a certain number $x$. We will also see Legendre's version of this sieve and apply it to obtain an upper bound for the number of primes up to $x$. Twin primes are pairs of primes that differ by $2$. We state a general version of the sieve of Eratosthenes and use it to prove a celebrated result about twin primes by Viggo Brun, which says that the sum of the reciprocals of the twin primes converges.
Date: Feb 6, 2024
Title: GROUP ACTIONS AND COUNTING.
Abstract: Group action is a powerful technique which has been used in almost every branch of mathematics, it pops up when there are some symmetries playing around. In this talk we will have a glance how Group action is used in combinatorics to solve some counting problems. Painful, but have to do some bookkeeping, we begin by discussing the definition of a group and group actions, and simple examples of both, such as the group of symmetries of a square and this group’s action upon a vertex. We proceed to then define both an orbit and a stabilizer, and prove the Orbit-Stabilizer Theorem, which is central to proving Burnside’s Lemma. Subsequently, we exemplify how Burnside’s Lemma can help us solve combinatorial problems. Namely, we compute the number of distinct colourings of a geometric pattern and the number of distinct necklaces that can be made with coloured beads by utilizing Burnside’s Lemma.
Date: Jan 21, 2024
Title: Introduction to Spherical Varieties
Abstract: A spherical variety X is a variety with an action of a connected reductive algebraic group G, which contains an open B-orbit, where B is a Borel subgroup of G. In this talk, I will start with some preliminaries of variety, and algebraic groups. After that, I will introduce spherical variety and some examples.
Date: Nov 8, 2023
Title: An overview of V-line transform and some generalizations.
Abstract: In inverse problems related to integral geometry, one of the fundamental goals is to recover the scalar field (or, more generally, tensor field) from its integral along some suitable trajectories. In this talk, we will focus on the integrals along V-shaped trajectories, known as V-line transforms. We will start with a motivation for V-line transforms. Then, we will discuss some generalized V-line transforms for vector fields in the plane and provide some geometrical proofs. If time permits, we will discuss some other generalized V-line transforms.
Date: Oct 4, 2023
Title: The history of matrix positive semidefiniteness preservers
Abstract: What functions preserve positive semidefiniteness when applied entrywise to positive semidefinite matrices? This question has a long history beginning with Schur, Schoenberg, and Rudin, and has also recently received renewed attention due to its several applications in statistics. However, effective characterizations of entrywise functions preserving positivity in a fixed dimension remain open to date. In this talk, I will give a historical account and state-of-the-art of this problem.
Date: Sep 27, 2023
Title: An Overview of Inverse Boundary Value Problems
Abstract: In this talk, we will discuss the inverse boundary value problem that determines the internal coefficients of the differential equation from measurements made at the region's boundary and its applications. We will further introduce Calderón's Problem (also called the inverse conductivity problem) and discuss some main tools for proving the uniqueness of the inverse boundary value problems
Date: Sep 20, 2023
Title: Radon transform in CT scans
Abstract: In this talk, we plan to discuss some problems arising in the field of integral geometry having applications in various imaging techniques. We will discuss in detail about the Radon transform and its importance in the technique of CT scans. If time permits, we will discuss some other important integral transforms.
Date: Sep 13, 2023
Title: Counting Ideals in Numerical Semigroups
Abstract: If $S$ is a numerical semigroup, let $m(S,k)$ denote the number of ideals of $S$ with codimension $k$ and let $n(S,k)$ denote the number of ideals of $S$ with conductor $k$. We compute the generating function of the sequence $m(S,k)$ for all numerical semigroups of embedding dimension $2$ and for $S = \langle 3,n+2,2n+1\rangle$. We also prove that the sequence $n(S,k)$ becomes stationary after a certain term and compute these stationary terms for numerical semigroups of the form $\langle n,n+1 \rangle$.
Date: Aug 23, 2023
Title: Extreme values of the zeta function
Abstract: We compute extreme values of the Riemann zeta function at the critical points of the zeta function in the critical strip. i.e. the points where $\zeta^{\prime}(s)=0$ and $\Re s<1$. We show that the values taken by the zeta function at these points are very similar to the extreme values taken without any restrictions. We will show the geometric significance of such points.
We also compute extreme values of Dirichlet $L$ - functions at the critical points of the zeta function to the right of $\Re s=1$. It shows the statistical independence of $L$-functions and zeta function in a certain way as these values are very similar to the values taken by $L$-functions without any restriction.
Date: Aug 16, 2023
Title: Fundamental Solution to the Laplace Operator
Abstract: The concept of weak solution is an important aspect of the theory of partial differential equations; in this regard, we will study the basics of Distributions and convolution of functions and generalize it to convolution of distributions. Using these concepts, we will construct a fundamental solution to the Laplace operator.
Date: Aug 10, 2023
Title: A brief overview of C*- algebra
Abstract: C*-algebra: Some facts from Banach algebra, definition and example of C*-algebra, classification of commutative unital C*-algebra (If time permits brief overview for non-commutative case)
Date: May 3, 2023
Title: Primes in Short Intervals
Abstract: It is well-known that the number of primes up to $x$ is approximately $x/ log x$. If primes are "well-distributed" over positive integers, one would expect that in an interval $(x,x+h(x))$, there are $h(x)/ log x$ many primes. In other words, we may ask that for which functions $h$ we should expect this to hold. Well, it is not easy to answer this question, but what we can do is understand for which functions this does not hold. We will answer this using Maier's matrix method and discuss some consequences of this elegant method.
Date: Apr 27, 2023
Title: Good Reduction Criterion for Elliptic Curves
Abstract: Elliptic curves are central objects in arithmetic and geometry. Let E be an elliptic curve over rational numbers. Given a prime p, it is crucial to know whether this curve remains smooth after reduction modulo p or not. If it remains smooth, we say E has a good reduction at p. In this talk, we will discuss the good reduction criterion of E in terms of the Galois representation associated with E. This is a beautiful instance where E's arithmetic and geometric properties encode each other.
Date: Apr 5, 2023
Title: Orthogonal Decompositions and Twisted Isometries
Abstract: We introduce the notions of Twisted Isometries and Doubly Twisted Isometries on Hilbert Spaces. We show the existence of Orthogonal Decomposition for the above classes of isometries. We also identify tuples of isometries that admit a Wold-Von Neumann Decomposition.
Date: Mar 29, 2023
Title: Surreal Numbers and Their Construction
Abstract: As Mathematicians, we at some point learn about how number systems were constructed. We will try and understand a new unconventional way of constructing a wider (much much) set of numbers. All is fun & games until we start getting confused, don’t worry, there is a definition for us to get confused as well. It all starts with a simple game, Hackenbush, which we try and win, which will lead us to a newer type of numbers. Surreal numbers they are called, which almost seem to be real. This talk will include Analysis, Combinatorics, and some puzzles. Sharpen your axes before the talk!
Date: Mar 22, 2023
Title: Distribution Theory and its applications to PDE
Abstract: Distributions are an important tool in modern analysis, especially in the field of partial differential equations. Distributions are generalized functions that allow for operations, such as differentiation and convolution, on objects that fail to be functions. The talk aims to introduce the basic theory of distributions.
Date: Mar 15, 2023
Title: Polynomial Ideals associated with Finite Graphs
Abstract: We will discuss how finite graphs are associated with the ideals of polynomial rings and the motivation behind studying those ideals. We will see how the combinatorics of graphs play a crucial role in determining the primary decompositions of those ideals.
Date: Feb 1, 2023
Title: The Frobenius Problem: An Algebraic Approach
Abstract: This problem was discussed by Georg Ferdinand Frobenius (1849-1917) in the late 1800s. The problem is finding the largest integer, which can not be written as a non-negative integral combination of the given natural numbers with one as their greatest common divisor. This integer is called the Frobenius number. This problem seems fundamental in arithmetic but is known as NP-hard. In this lecture, we will discuss the proof of the fact that the Frobenius number of a numerical semigroup is the degree of the Hilbert series (as a rational function) of the associated semigroup algebra.
Date: Jan 19, 2023
Title: Polyominoes and Polyomino Algebras
Abstract: Combinatorial commutative algebra is the intersection of combinatorics and commutative algebra, and utilizes the tools of one to study the fundamental structures of the other. In this talk, we study the $K$-algbera $K[\mathcal{P}]$ (over a field $K$) associated to a polyomino $\mathcal{P}$, which is a combinatorial object. We see that some algebraic properties of $K[\mathcal{P}]$ can be related to the combinatorial properties of $\mathcal{P}$.
Date: Jan 11, 2023
Title: An Introduction to Game Theory
Abstract: Game theory is the study of mathematical models of strategic interactions among rational agents. It has applications in all fields of social science, as well as in logic, systems science, and computer science. In this talk, we will formally define what are two-player and n-player games and demonstrate some examples, such as Prisoner’s dilemma. We will cover the concepts of payoff matrices, zero-sum games, pure strategy, and mixed strategy. We will define the concept of Pure Strategy Nash Equilibrium (PSNE) and Mixed Strategy Nash Equilibrium (MSNE), and we will cover more topics if time permits. This talk will not assume any prior knowledge of algorithms or complexity theory from the audience.
Date: Nov 22, 2022
Title: d-holomorphic vector bundles
Abstract: In 1957, Michael Atiyah developed the theory of holomorphic connection on principal bundles over compact complex manifolds and gave a criterion (now known as the Atiyah-Weil criterion) for the existence of holomorphic connection on holomorphic vector bundles over compact Riemann surfaces. In 1882, Felix Klein introduced the Klein surface, and further analytic theory on Klein surfaces was studied in more depth by Schiffer and Spencer in 1954. Norman Alling and Newcomb Greenleaf studied the correspondence between Klein surfaces and real algebraic function fields. In this talk, we will discuss the theory of d-holomorphic vector bundles, and if time permits, we will talk about d-holomorphic connections.
Date: Nov 15, 2022
Title: Euler Gamma Function and its various generalizations
Abstract: We will define Euler’s gamma function and its various generalized and related special functions. Also, introduce its important properties like a functional equation, difference equation, reflection formula, etc. We will also look for a result on the generalized Mittag-Leffler functions and technique used in its proof.
Date: Nov 8, 2022
Title: Euler Gamma Function and its various generalizations
Abstract: We will define Euler’s gamma function and its various generalized and related special functions. Also, introduce its important properties like a functional equation, difference equation, reflection formula, etc. We will also look for a result on the generalized Mittag-Leffler functions and technique used in its proof.