Following the recent observation of non-zero spin polarization and spin
alignment of a few hadrons, the rotational aspect of quark-gluon plasma formed
in heavy ion collisions has attracted considerable interest. The present work
explores the effect of the Coriolis force, arising due to this rotation, on the
shear viscosity of the medium. Using the relaxation time approximation within
the kinetic theory framework, we analyze the parallel (\(\eta_{||}/s\)),
perpendicular (\(\eta_\perp/s\)) and Hall (\(\eta_\times/s\)) components of
shear viscosity to entropy density ratio under rotation. The estimation of
anisotropic shear viscosity components is carried out using hadron resonance
gas degrees of freedom below the critical (transition) temperature and massless
partonic degrees of freedom above this temperature. Our results show that
rotation suppresses the shear viscosity of the medium, with the degree of
suppression depending on the ratio between the relaxation time and the
rotational period. In the context of realistic heavy-ion collision experiments,
the temperature and angular velocity both decrease with time, and one can
establish a connection between them through the standard approximate cooling
law. For a temperature-dependent angular velocity \(\Omega(T)\), we obtain a
traditional valley-like pattern for all components \(\eta_{||}/s\),
\(\eta_\perp/s\) and \(\eta_\times/s\) with reduced magnitudes compared to the
valley-like isotropic $\eta/s$ one encounters in the absence of rotation.

Este artículo explora los viajes en el tiempo y sus implicaciones.

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