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arXiv · 0909.4713

Pentagrams and paradoxes

Piotr Badziag·Ingemar Bengtsson·Adan Cabello·Helena Granstrom·Jan-Åke Larsson
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Abstract

Klyachko and coworkers consider an orthogonality graph in the form of a pentagram, and in this way derive a Kochen-Specker inequality for spin 1 systems. In some low-dimensional situations Hilbert spaces are naturally organised, by a magical choice of basis, into SO(N) orbits. Combining these ideas some very elegant results emerge. We give a careful discussion of the pentagram operator, and then show how the pentagram underlies a number of other quantum "paradoxes", such as that of Hardy.

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Piotr Badziag, Ingemar Bengtsson, Adan Cabello, Helena Granstrom, Jan-Åke Larsson. 2009-09-25. Pentagrams and paradoxes. https://doi.org/10.1007/s10701-010-9433-3

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