The analytic properties of L-functions associated to automorphic forms
My primary interests centre around characterising L-functions by means of their analytic properties and in establishing the desired analytic properties for L-functions associated to automorphic forms. Recent work has involved the exterior square L-functions associated to GLn (over local and global fields) and primitivity results for the L-functions of cusp forms associated to GL3 in the extended Selberg class.
Blow-up algebras, Hilbert functions and local cohomology
My current research focuses on Hilbert functions of admissible filtrations of ideals in Cohen-Macaulay rings. These rings are central objects of study in commutative algebra. Through the knowledge of their Hilbert polynomials we can obtain information about various blow-up algebras such as Rees algebras, associated graded rings and the ring itself. Information about these algebras is often useful in resolution of singularities as demonstrated in the works of Abhyankar, Hironaka, Sally, Zariski and others.
Subnormal operators
Study of special classes of operators on Hilbert spaces such as subnormal operators using Complex Analysis and Homological Algebra.
Dilation of pair of commuting contractions
My current research area of interest is operator theory. To be more precise, my most recent works are based on dilation of operators. Dilation is a mathematical tool which largely used in different branches of Mathematics to understand the underlying object better. With no exception, dilation of operators is used to understand operators which are not normal. A brief summary of my recent works in this area are given below.
Invariants for liftings of operator tuples and its applications
Based on a careful analysis of functional models for contractive multi-analytic operators we have established a one-to-one correspondence between unitary equivalence classes of minimal contractive liftings of a row contraction and injective symbols of contractive multi-analytic operators. This allows an effective construction and classification of all such liftings with given defects. G. Popescu’s theory of characteristic functions of completely non-coisometric row contractions is obtained as a special case satisfying a Szeg ̈o condition.
CPD-kernels, k-families and Bures distance
We introduced, for any set S, the concept of K-family between two Hilbert C∗-modules over two C∗-algebras, for a given completely positive definite (CPD-) kernel K over S between those C∗-algebras and obtained a factorization theorem for such K-families. If K is a CPD-kernel and E is a full Hilbert C∗-module, then any K-family which is covariant with respect to a dynamical system (G, η, E) on E, extends to a K ̃-family on the crossed product E×ηG, where K ̃ is a CPD-kernel.
Approximate solutions of integral equations and of associated Eigen value problems
The theory and application of integral equations is an important subject within applied mathematics. Integral equations are used as mathematical models for many physical situations. I am interested in a numerical solution of the Fredholm integral equation of the second kind. The integral operator T is either a linear integral operator or a nonlinear Urysohn integral operator. The eigenvalue problem associated with a linear integral operator T is of equal interest.
Analysis of the Wu metric on Thullen domains in Cn
H. Wu constructed a new Hermitian metric that provides an interesting interpolant between the Finsler (like the Carath ́eodory and Kobayashi metrics) and the K ̈ahler invariant metrics. The Wu metric raises several intriguing questions some of which I investigated. One of them is closely related to a problem posed by Kobayashi in 1970: It is well known that if M is a Hermitian manifold with negative holomorphic curvature, then M is Kobayashi hyperbolic.
Interplay between complex geometry and operator theory on two domains in C3
We have studied complex geometry and operator theory on polynomially convex and inhomogeneousdomains in C3 namely the tetrablock and the symmetrized tridisc which in literature are denoted by E and Γ3 respectively and are defined in the following way
Extremal & probabilistic combinatorics
I work primarily in extremal and probabilistic combinatorics. Most problems of an extremal nature involve a set (_nite) with certain constraints (which are of a combinatorial nature) and one is then interested in how large/how small such a family could be. In classical problems of extremal combinatorics, the extremal families also admit short (low complexity) descriptions.