Physical Chirality. It Feeds on Negative Entropy

G. Gilat

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Physical Chirality. It Feeds on Negative Entropy

G. Gilat

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Abstract

Chirality is considered by many scientists to be mainly a geometric concept. There exists also a physical aspect of chirality which is largely being overlooked at. Two examples of mechanical devices are introduced here that represent ``Physical Chirality''. These are a rotating water sprinkler and a variant of Crookes' radiometer. When interacting with appropriate media, they both choose only one mode of rotation out of two possible ones. Such a behavior does not obey time-reversal invariance, which is regarded to be a rule in classical mechanics. This is due to their chiral nature. Instead, they do obey a space-time (ST) law of invariance, that is, what is rotating in the opposite direction is the mirror-image of the given device. In a recent experiment of Koumura et al. they discovered a similar behavior of a molecular rotor. The possible biological significance of physical chirality is emphasized hereby, and the conclusion is that chiral molecular systems do not reach readily thermal equilibrium. In other words: ``Physical chirality does feed on negative entropy'', and therefore, it may well be of crucial value to life.

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G. Gilat. 2002-06-23. Physical Chirality. It Feeds on Negative Entropy. https://arxiv.org/abs/physics/0206074

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