activity
20242026
collaborators

5 papers

math.OC2026

Finite de Finetti for convex bodies and Polynomial Optimization

Julius A. Zeiss, Gereon Koßmann, René Schwonnek +1

Leveraging a recently proposed notion of relative entropy in general probabilistic theories (GPT), we prove a finite de Finetti representation theorem for general convex bodies. We…

quant-ph2026

A Collection of Pinsker-type Inequalities for Quantum Divergences

Kläre Wienecke, Gereon Koßmann, René Schwonnek

Pinsker's inequality sets a lower bound on the Umegaki divergence of two quantum states in terms of their trace distance. In this work, we formulate corresponding estimates for a v…

quant-ph2025

Simultaneous variances of Pauli strings, weighted independence numbers, and a new kind of perfection of graphs

Zhen-Peng Xu, Jie Wang, Qi Ye +3

A set of Pauli stings is well characterized by the graph that encodes its commutatitivity structure, i.e., by its frustration graph. This graph provides a natural interface between…

quant-ph2025

On approximate quantum error correction for symmetric noise

Gereon Koßmann, Julius A. Zeiss, Omar Fawzi +1

We revisit the extendability-based semi-definite programming hierarchy introduced by Berta et al. [Mathematical Programming, 1 - 49 (2021)], which provides converging outer bounds…

quant-ph2024

Reliable Entropy Estimation from Observed Statistics for Device-Independent Quantum Cryptography

Gereon Koßmann, René Schwonnek

This paper introduces a numerical framework for establishing lower bounds on the conditional von-Neumann entropy in device-independent quantum cryptography and randomness extractio…