Sander Gribling

Address: Tilburg University, Koopmans building, Warandelaan 2

Office: K 501

email: s.j.gribling at tilburguniversity dot edu

## News:

Very excited about a new preprint: Quantum speedups for linear programming via interior point methods (with Simon Apers). Accepted as a talk at QIP 2024.

Since August 2023 I am an assistant professor @ Tilburg University!

Some recent preprints:

A note on the computational complexity of the moment-SOS hierarchy for polynomial optimization (with Lucas Slot and Sven Polak), published in the proceedings of ISSAC 2023 here.

A (simple) classical algorithm for estimating Betti numbers (with Simon Apers, Sayantan Sen, and Dániel Szabó).

Basic quantum subroutines: finding multiple marked elements and summing numbers (with Joran van Apeldoorn & Harold Nieuwboer),

Grothendieck inequalities characterize converses to the polynomial method (with Jop Briët & Francisco Escudero Gutiérrez),

Hamiltonian Monte Carlo for efficient Gaussian sampling: long and random steps (with Simon Apers & Dániel Szilágyi).

## About me:

Since August 2023 I am an assistant professor at Tilburg University in the department of Econometrics & Operations Research.

Previously, from September 2020 I was a postdoc at IRIF (Université Paris Cité) in the Algorithms and Complexity group. Before that, from 2019 to 2020, I was a postdoc at Centrum Wiskunde & Informatica (CWI) in the research group Networks & Optimization.

From September 2015 to September 2019, I was a PhD student in the same group at CWI. I have defended my thesis "Applications of optimization to factorization ranks and quantum information theory" at the Tilburg University on September 30th, 2019.

[CV] (last updated: September 2023)

## Research interests:

Broadly speaking, I am interested in convex optimization and quantum information theory / quantum computing. Some of my favorite topics include:

Quantum algorithms for classical optimization problems (e.g., SDP-solvers, convex optimization, matrix scaling)

Semidefinite programming and in particular its connection to polynomial optimization

Polynomial optimization approaches to matrix factorization ranks, quantum graph parameters, and most recently mutually unbiased bases

## Employment:

Assistant professor at Tilburg University

From 08/2023, in the department of Econometrics and Operations Research.

Postdoc at IRIF, Université Paris Cité

From 09/2020 to 07/2023, in the Algorithms and Complexity group.

Postdoc at CWI & QuSoft

From 10/2019 to 08/2020, in the Networks & Optimization group.

PhD student at CWI & QuSoft

From 09/2015 to 09/2019, in the Networks & Optimization group.

Advisors: Monique Laurent & Ronald de Wolf.

Publications / preprints:

Quantum speedups for linear programming via interior point methods.

with Simon Apers. QIP 2024

A note on the computational complexity of the moment-SOS hierarchy for polynomial optimization

with Lucas Slot and Sven Polak. Proceedings of ISSAC 2023, pages 280--288.

Basic quantum subroutines: finding multiple marked elements and summing numbers .

with Joran van Apeldoorn & Harold Nieuwboer.

Grothendieck inequalities characterize converses to the polynomial method.

with Jop Briët & Francisco Escudero Gutiérrez.

A (simple) classical algorithm for estimating Betti numbers

with Simon Apers, Sayantan Sen, and Dániel Szabó.

Hamiltonian Monte Carlo for efficient Gaussian sampling: long and random steps.

with Simon Apers & Dániel Szilágyi.

Mutually unbiased bases: polynomial optimization and symmetry.

with Sven Polak.

Improved quantum lower and upper bounds for matrix scaling.

with Harold Nieuwboer. STACS'22.

Bounding the separable rank via polynomial optimization.

with Monique Laurent & Andries Steenkamp. Linear Algebra and Its Applications, Volume 648, pages 1-55, September 2022.

Approximate Pythagoras Numbers .

with Paria Abbasi, Andreas Klingler & Tim Netzer. Journal of Complexity, available online, August 2022.

Improving quantum linear system solvers via a gradient descent perspective .

with Iordanis Kerenidis & Dániel Szilágyi.

On a tracial version of Haemers bound .

with Li Gao & Yinan Li. AQIS'20 and Beyond IID in Information Theory'20.

Journal version: IEEE Transactions on Information Theory, vol. 68, no. 10, pp. 6585-6604, Oct. 2022, doi:10.1109/TIT.2022.3176935.

Quantum algorithms for matrix scaling and matrix balancing.

with Joran van Apeldoorn, Yinan Li, Harold Nieuwboer, Michael Walter & Ronald de Wolf. TQC'21. ICALP'21, conference version.

The Haemers bound of noncommutative graphs.

with Yinan Li. QIP'20. IEEE Journal on Selected Areas in Information Theory, Volume 1, Issue 2, pp 424-431, 2020.

Semidefinite programming formulations for the completely bounded norm of a tensor.

with Monique Laurent. QIP'19 (part of a joint submission).

Simon's problem for linear functions.

with Joran van Apeldoorn.

Convex optimization using quantum oracles.

with Joran van Apeldoorn, András Gilyén & Ronald de Wolf. QIP'19. The journal version appeared in Quantum.

with Aida Abiad, Domenico Lahaye, Matthias Mnich, Guus Regts, Lluis Vena, Gerard Verweij, Peter Zwaneveld. Discrete Optimization Volume 37, August 2020.

Quantum SDP-Solvers: Better upper and lower bounds.

with Joran van Apeldoorn, András Gilyén & Ronald de Wolf. FOCS'17, conference version. The journal version appeared in Quantum.

Lower bounds on matrix factorization ranks via noncommutative polynomial optimization

with David de Laat & Monique Laurent. Mathematical Programming Series B, Volume 170, Issue 1, pp 5–42, 2018.

Matrices with high completely positive semidefinite rank.

with David de Laat & Monique Laurent. Linear Algebra and Its Applications, 513, 122-148, 2017.

## Education:

Msc. in Applied Mathematics - TU Delft

From 09/2013 to 05/2015.

A local search approach to resolving capacity issues in mobile cellular networks. Master thesis, TU Delft, 2015.

Advisors: Karen Aardal, Dion Gijswijt, Tanneke Ouboter, Hans van den Berg.

Bsc. in Applied Mathematics - TU Delft

From 09/2010 to 09/2013.

The ellipsoid method and an application to the Lovász-theta-function. Bachelor thesis, TU Delft, 2013.

Advisor: Frank Vallentin.

## Theses:

Applications of optimization to factorization ranks and quantum information theory. PhD thesis, University of Tilburg, 2019.

Advisors: Monique Laurent & Ronald de Wolf.

A local search approach to resolving capacity issues in mobile cellular networks. Master thesis, TU Delft, 2015.

Advisors: Karen Aardal, Dion Gijswijt, Tanneke Ouboter, Hans van den Berg.

The ellipsoid method and an application to the Lovász-theta-function. Bachelor thesis, TU Delft, 2013.

Advisor: Frank Vallentin.