The strong interaction is the fundamental force that binds quarks and gluons into hadrons,such as protons and neutrons,and further binds protons and neutrons into nuclei.Undrstanding the nature and properties of strong interactions is one of the most prominent research frontiers of contemporary physics.However,liberating quarks and gluons from hadrons requires extremely high temperatures or densities,which can only be achieved by relativistic heavy-ion collisions on Earth.These collisions can generate extremely high-temperature deconfined,interacting quark-gluon systems called quark-gluon plasma(QGP).In the past decade or so,people have gradually realized that such collisions can also generate strong electromagnetic fields and fluid vortical fields.These fields directly affect the spin and orbital motion of microscopic particles within the QGP,inducing novel macroscopic quantum phenomena such as chiral magnetic effects,chiral vortical effects,chiral separation effects,chiral electric separation effects,and other chiral anomalous transport phenomena.These effects represent the induction of electric or axial currents along an applied magnetic field,electric field,or vortical field.They are closely tied to the underlying quatum anomaly of quantum chromodynamics(QCD)and the chiral symmetry restoration in QGP.Additionally,phenomena like hyperon spin polarization and vector meson spin alignment may also occur,and the QCD phase structure may also be affected by strong electromagnetic and vortical fields.On one hand,these phenomena provide experimental means for probing nontrivial gauge field topological structures in QCD,strong interaction CP violation,and spin dynamics in quark-gluon matter during heavy-ion collisions.On the other hand,they are closely related to particle physics,condensed matter physics,astrophysics,and form active areas of interdisciplinary research.This paper will review and provide prospects for the mechanisms behind the generation of these macroscopic quantum phenomena and their experimental signals in heavy-ion collisions,we focus on the following topics:(1)The generation of strong electromagnetic fields and fluid vortical fields in heavy-ion collisions,and the special properties of these fields such as their dependence on the collision energy and the collision centrality,their event-by-event fluctuations.We present both intuitive arguments and rigorous numerical results covering this topic.(2)The theoretical basis and experimental signals of chiral anomalous transport phenomena,especially that we present a detailed derivation of the chiral magnetic and vortical effects using hydrodynamic approaches.(3)Plasma instability caused by chiral magnetic and vortical effects,in particular,the so-called chiral plasma instability and the newly-found chiral magnetovortical instability.This new instability is due to the interplay of the chiral vortical effect and a background magnetic field which can induce a novel dynamo effect in chiral plasma.(4)Spin polarization phenomena in QGP including the hyperon spin polarization and verctor meson spin alignment which have driven intensive discussions recently.In particular,we discuss the current understanding of the spin polarization and spin alignment phenomena and some puzzles such as the sign problem in the hyperon local spin polarizaiton.
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