activity
20202026
most citedPositivity preservers over finite fields

3 citations · 6 across the 15 of their papers we have counts for

collaborators

15 papers

math.FA2026

Finite-orbit obstructions for multipliers on the polydisk

Ilya Krishtal, Javad Mashreghi, Prateek Kumar Vishwakarma

We study the closed spans of finitely many joint orbits of holomorphic multipliers on the Hardy space of the polydisk. If fewer than symbols are used, every…

math.MG2026

Hyperbolic distance matrix completion

Mihai Putinar, Prateek Kumar Vishwakarma

A completion theory for hyperbolic distance data is developed at the interface of matrix analysis, graph theory, and hyperbolic geometry. Krein's characterization of the metric spa…

math.RA2026

Positivity preservers over finite fields II

Dominique Guillot, Himanshu Gupta, Prateek Kumar Vishwakarma +1

We say that a matrix over a finite field is positive definite if it is symmetric and each of its leading principal minors is a nonzero square in . In p…

math.FA2026

Oppenheim--Schur inequalities for causal products

Dominique Guillot, Javad Mashreghi, Prateek Kumar Vishwakarma

We establish a class of Oppenheim--Schur-type inequalities for the convolutional Jury product of positive semidefinite matrices. These results extend to a causal convolutional sett…

math.FA2026

Sharp lower bounds for generalized operator products

Dominique Guillot, Javad Mashreghi, Prateek Kumar Vishwakarma

We consider general bilinear products defined by positive semidefinite matrices. Typically non-commutative, non-associative, and non-unital, these products preserve positivity and…

math.FA2025

Functional Calculi, Positivity, and Convolution of Matrices

Javad Mashreghi, Mostafa Nasri, Prateek Kumar Vishwakarma

Convolution admits a natural formulation as a functional operation on matrices. Motivated by the functional and entrywise calculi, this leads to a framework in which convolution de…

math.CO2025★ 1 cited

Cholesky decomposition for symmetric matrices over finite fields

Prateek Kumar Vishwakarma

Inspired by the seminal work of André-Louis Cholesky -- whose contributions remain crucial in broader sciences even after more than a century -- Cooper, Hanna and Whitlatch (2024)…

math.RA2025

Cholesky decomposition for symmetric matrices, Riemannian geometry, and random matrices

Apoorva Khare, Prateek Kumar Vishwakarma

For each and sign pattern , we introduce a cone of real symmetric matrices : those with leading principal minors of signs $ε_k…

math.CA2025★ 1 cited

Entrywise transforms preserving matrix positivity and non-positivity

Dominique Guillot, Himanshu Gupta, Prateek Kumar Vishwakarma +1

We characterize real and complex functions which, when applied entrywise to square matrices, yield a positive definite matrix if and only if the original matrix is positive definit…

math.CO2025

Chevalley operations on TNN Grassmannians

Prateek Kumar Vishwakarma

Lusztig showed that invertible totally nonnegative (TNN) matrices form a semigroup generated by positive diagonal matrices and Chevalley generators. From its Grassmann analogue, we…

math.RA2024★ 3 cited

Positivity preservers over finite fields

Dominique Guillot, Himanshu Gupta, Prateek Kumar Vishwakarma +1

We resolve an algebraic version of Schoenberg's celebrated theorem [Duke Math.J., 1942] characterizing entrywise matrix transforms that preserve positive definiteness. Compared to…

math.CO2023

Plücker inequalities for weakly separated coordinates in totally nonnegative Grassmannian

Daniel Soskin, Prateek Kumar Vishwakarma

We show that the partial sums of the long Plücker relations for pairs of weakly separated Plücker coordinates oscillate around on the totally nonnegative part of the Grassmanni…

math.CA2023★ 1 cited

Inequalities for totally nonnegative matrices: Gantmacher--Krein, Karlin, and Laplace

Shaun M. Fallat, Prateek Kumar Vishwakarma

A real linear combination of products of minors which is nonnegative over all totally nonnegative (TN) matrices is called a determinantal inequality for these matrices. It is refer…

math.CO2023

The Strong Spectral Property of Graphs: Graph Operations and Barbell Partitions

Sarah Allred, Emelie Curl, Shaun Fallat +4

The utility of a matrix satisfying the Strong Spectral Property has been well established particularly in connection with the inverse eigenvalue problem for graphs. More recently t…

math.CA2020

Positivity preservers forbidden to operate on diagonal blocks

Prateek Kumar Vishwakarma

The question of which functions acting entrywise preserve positive semidefiniteness has a long history, beginning with the Schur product theorem [Crelle 1911], which implies that a…