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Pomeron evolution, entanglement entropy, and Abramovskii-Gribov-Kancheli cutting rules

Mustapha Ouchen and Alex Prygarin

Phys. Rev. D 112, 094027 – Published 17 November, 2025

DOI: https://doi.org/10.1103/cpvq-f5gx

Abstract

We use Pomeron evolution equation in zero transverse dimension based on the Abramovskii-Gribov-Kancheli (AGK) cutting rules to calculate the von Neumann entropy and q moments that are used as an experimental test for the Koba-Nielsen-Olesen scaling. In order to avoid the negative probabilities that emerge from the negative AGK weights in the Minkowski space, we reformulate the Pomeron evolution in the Euclidean space. The resulting positive definite probabilities for cut and uncut Pomerons are used in calculating the q moments. The comparison to the experimental data shows that our AGK-based model successfully describes q-moment dependence on the mean multiplicity without any adjustable parameter in the experimental data of the p−p collisions by the ALICE Collaboration.

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