activity
20202026
most citedThe minimal canonical form of a tensor network

14 citations · 34 across the 12 of their papers we have counts for

collaborators

15 papers

cs.IT2026

A simple proof of the group-theoretic Zhang-Yeung inequality

Harold Nieuwboer, Lubashan Pathirana

Zhang and Yeung (IEEE Trans. Inf. Theory, 1998) established the first non-Shannon-type inequality that holds for all entropic vectors. Chan and Yeung (IEEE Trans. Inf. Theory, 2002…

quant-ph2026

Robustness of Hidden-Variable Theories and Matrix Scaling

Giulio Malavolta, Harold Nieuwboer, Akshay Ramachandran +1

Motivated by quantum foundations and complexity theory, Aaronson formalized a hidden-variable theory inspired by a proposal by Schrödinger. To any quantum state and unitary, this S…

math.AG2026

On quantum functionals for higher-order tensors

Alonso Botero, Matthias Christandl, Thomas C. Fraser +2

Upper and lower quantum functionals, introduced by Christandl, Vrana and Zuiddam (STOC 2018, J. Amer. Math. Soc. 2023), are families of monotone functions of tensors indexed by a w…

math.OC2026

Negative curvature obstructs the existence of good barriers for interior-point methods

Christopher Criscitiello, Harold Nieuwboer, Michael Walter

Interior-point methods (IPMs) are a cornerstone of Euclidean convex optimization, due to their strong theoretical guarantees and practical performance. Motivated by scaling problem…

math.RT2025

Computing moment polytopes -- with a focus on tensors, entanglement and matrix multiplication

Maxim van den Berg, Matthias Christandl, Vladimir Lysikov +3

Tensors are fundamental in mathematics, computer science, and physics. Their study through algebraic geometry and representation theory has proved very fruitful in the context of a…

quant-ph2025

Self-concordant Schrödinger operators: spectral gaps and optimization without condition numbers

Sander Gribling, Simon Apers, Harold Nieuwboer +1

Spectral gaps play a fundamental role in many areas of mathematics, computer science, and physics. In quantum mechanics, the spectral gap of Schrödinger operators has a long histor…

math.AG2025

Explicit non-free tensors

Maxim van den Berg, Matthias Christandl, Vladimir Lysikov +3

Free tensors are tensors which, after a change of bases, have free support: any two distinct elements of its support differ in at least two coordinates. They play a distinguished r…

cs.CC2025

The moment polytope of matrix multiplication is not maximal

Maxim van den Berg, Matthias Christandl, Vladimir Lysikov +3

Moment polytopes of tensors, the study of which is deeply rooted in invariant theory, representation theory and symplectic geometry, have found relevance in numerous places, from q…

cs.CC2024

Asymptotic tensor rank is characterized by polynomials

Matthias Christandl, Koen Hoeberechts, Harold Nieuwboer +2

Asymptotic tensor rank is notoriously difficult to determine. Indeed, determining its value for the matrix multiplication tensor would determine the matrix multiplicati…

math.OC2023★ 9 cited

Interior-point methods on manifolds: theory and applications

Hiroshi Hirai, Harold Nieuwboer, Michael Walter

Interior-point methods offer a highly versatile framework for convex optimization that is effective in theory and practice. A key notion in their theory is that of a self-concordan…

quant-ph2023★ 3 cited

Basic quantum subroutines: finding multiple marked elements and summing numbers

Joran van Apeldoorn, Sander Gribling, Harold Nieuwboer

We show how to find all marked elements in a list of size using the optimal number of quantum queries and only a polylogarithmic overhead in the gate comple…

quant-ph2022★ 14 cited

The minimal canonical form of a tensor network

Arturo Acuaviva, Visu Makam, Harold Nieuwboer +4

Tensor networks have a gauge degree of freedom on the virtual degrees of freedom that are contracted. A canonical form is a choice of fixing this degree of freedom. For matrix prod…

quant-ph2021

Improved quantum lower and upper bounds for matrix scaling

Sander Gribling, Harold Nieuwboer

Matrix scaling is a simple to state, yet widely applicable linear-algebraic problem: the goal is to scale the rows and columns of a given non-negative matrix such that the rescaled…

quant-ph2020★ 1 cited

Quantum algorithms for matrix scaling and matrix balancing

Joran van Apeldoorn, Sander Gribling, Yinan Li +3

Matrix scaling and matrix balancing are two basic linear-algebraic problems with a wide variety of applications, such as approximating the permanent, and pre-conditioning linear sy…

math.OC2020★ 7 cited

Interior-point methods for unconstrained geometric programming and scaling problems

Peter Bürgisser, Yinan Li, Harold Nieuwboer +1

We provide a condition-based analysis of two interior-point methods for unconstrained geometric programs, a class of convex programs that arise naturally in applications including…