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arXiv · 2512.00432

The Connes-Kirchberg Problem and infinite-dimensional phenomena in quantum information theory

Magdalena Musat
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Abstract

We give an overview of results tying together a circle of problems connected to the Connes Embedding Problem, Kirchberg's reformulations thereof, Tsirelson's conjecture and its relation to quantum information theory, and a class of quantum channels, called factorizable, introduced by Anantharaman-Delaroche. While parts of the article are more expository, there are new results, including obstructions for channels to being $k$-noisy (admitting a factorization through a full matrix algebra).

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Magdalena Musat. 2025-11-29. The Connes-Kirchberg Problem and infinite-dimensional phenomena in quantum information theory. https://arxiv.org/abs/2512.00432

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