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arXiv · 2407.05950

Quantum states as countable convex combination of pure states with bounded energy

Juan Pablo Lopez
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Abstract

We give response to the question: in infinite dimension states,given a state with energy bounded by E, we can write the state as a countable convex combination of pure states with energy bounded by E. We review the Alicki-Fannes-Winter technique to obtain a uniform continuity bound for the von Neumann entropy in states that are a mix of pure states with bounded energy, using this bound we conclude that for a Hamiltonian satisfying the Gibb's hypothesis such states cannot exist.

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Juan Pablo Lopez. 2024-07-02. Quantum states as countable convex combination of pure states with bounded energy. https://arxiv.org/abs/2407.05950

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