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arXiv · 1801.00087

Classical and quantum entropy of parton distributions

Yoshikazu Hagiwara·Yoshitaka Hatta·Bo-Wen Xiao·Feng Yuan
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Abstract

We introduce the semiclassical Wehrl entropy for the nucleon as a measure of complexity of the multiparton configuration in phase space. This gives a new perspective on the nucleon tomography. We evaluate the entropy in the small-$x$ region and compare with the quantum von Neumann entropy. We also discuss the growth of entropy at small-$x$ and argue that it eventually saturates due to the Pomeron loop effect.

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Yoshikazu Hagiwara, Yoshitaka Hatta, Bo-Wen Xiao, Feng Yuan. 2017-12-30. Classical and quantum entropy of parton distributions. https://doi.org/10.1103/physrevd.97.094029

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