Pentaquarks and Maxim V. Polyakov

Abstract

This brief review is dedicated to the memory of Maxim V. Polyakov and his pioneering contributions to pentaquark physics. We focus on his seminal 1997 work with Diakonov and Petrov that predicted the $Θ^+$ pentaquark, a breakthrough that initiated an intense period of research in hadron physics. The field faced a significant setback when the CLAS Collaboration at Jefferson Lab reported null results in 2006, leading to a dramatic decline in light pentaquark research. Nevertheless, Maxim maintained his scientific conviction, supported by continued positive signals from DIANA and LEPS collaborations. Through recent experimental findings on the $Θ^+$ and the nucleon-like resonance $N^*(1685)$, we examine how Polyakov's theoretical insights, particularly the prediction of a narrow width ($Γ\approx 0.5$-$1.0$ MeV), remain relevant to our understanding of the $Θ^+$ light pentaquark.