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Nonlinear dynamics

Quantizing the classical cat

Nature volume 430, pages 731732 (12 August 2004) | Download Citation


A mathematical analysis of a pendulum system reveals the relevance to quantum systems of the classical concept of ‘monodromy’ — why a falling cat always lands the right way up.

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  1. Ian Stewart is at the Mathematics Institute, University of Warwick, Coventry CV4 7AL, UK.

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