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arXiv · 2411.01082

Quantum Potato Chips

Nikolay Murzin·Bruno Tenorio·Sebastian Rodriguez·John McNally·Mohammad Bahrami
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Abstract

We examine qubit states under symmetric informationally-complete measurements, representing state vectors as probability 4-vectors within a 3-simplex in $bb(R)^4$. Using geometric transformations, this 3-simplex is mapped to a tetrahedron in $bb(R)^3$. A specific surface within this tetrahedron allows for the separation of probability vectors into two disjoint 1-simplices. The intersection of this surface with the insphere identifies a "quantum potato chip" region, where probability 4-vectors reduce to two binary classical variables. States within this region can be fully reconstructed using only two given projective measurements, a feature not found elsewhere in the state space.

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Nikolay Murzin, Bruno Tenorio, Sebastian Rodriguez, John McNally, Mohammad Bahrami. 2024-11-01. Quantum Potato Chips. https://arxiv.org/abs/2411.01082

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