Using the conservation laws for charge, energy, momentum, and angular we derive hydrodynamic equations charge density, local temperature, fluid velocity, as well spin tensor, starting from equilibrium distribution functions particles antiparticles with 1/2. The resulting set of differential extend standard picture perfect-fluid hydrodynamics a conserved entropy current in minimal way. This framework can be used space-time analyzes evolution polarization various physical systems including...

We calculate the Wigner function for massive $\mathrm{spin}\text{\ensuremath{-}}1/2$ particles in an inhomogeneous electromagnetic field to leading order Planck constant $\ensuremath{\hbar}$. Going beyond $\ensuremath{\hbar}$ we then derive a generalized Boltzmann equation which force exerted by on particle dipole moment arises naturally. Furthermore, kinetic this is derived. Carefully taking massless limit find agreement with previous results. The case of global equilibrium rotation also...

We derive the collision term in Boltzmann equation using of motion for Wigner function massive spin-1/2 particles. To next-to-lowest order $\hbar$ it contains a nonlocal contribution, which is responsible conversion orbital into spin angular momentum. In proper choice pseudo-gauge antisymmetric part energy-momentum tensor arises solely from this contribution. show that vanishes only global equilibrium and potential then equal to thermal vorticity. nonrelativistic limit, equations tensors...

We derive relativistic second-order dissipative fluid-dynamical equations of motion for massive spin-1/2 particles from kinetic theory using the method moments. Besides usual conservation laws charge, energy, and momentum, such a spin hydrodynamics features an equation rank-3 tensor, which follows total angular momentum. Extending conventional moments spin-0 particles, we expand spin-dependent distribution function near local equilibrium in terms momentum variables. work to next-to-leading...

The thermal plasma in the early Universe produced a stochastic gravitational wave (GW) background, which peaks today microwave regime and was dubbed cosmic background (CGMB). In previous works, only single graviton production processes that contribute to CGMB have been considered. Here, we also investigate pair show these can lead significant contribution if ratio between maximum temperature Planck mass, <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"...

It is shown that the description of a relativistic fluid at local thermodynamic equilibrium depends on particular quantum stress-energy tensor operator chosen, e.g., canonical or symmetrized Belinfante tensor. We argue not appropriate to describe whose macroscopic polarization relaxes slowly and spin tensor, like required. As consequence, polarized involves an extension hydrodynamics including new antisymmetric rank-two as dynamical field. show tensors lead different predictions for...

Recently advocated expressions for the phase-space dependent spin-$\frac{1}{2}$ density matrices of particles and antiparticles are analyzed in detail reduced to forms linear Dirac spin operator. This allows a natural determination spin-polarization vectors by evaluating trace products Pauli matrices. We demonstrate that total vector obtained this way agrees with Pauli-Luba\ifmmode \acute{n}\else \'{n}\fi{}ski four-vector, constructed from an appropriately chosen tensor boosted particle rest...

We derive the Boltzmann equation and collision kernel for massive spin-$1/2$ particles, using Wigner-function formalism employing an expansion in powers of $\ensuremath{\hbar}$. The phase space is enlarged to include a variable related spin degrees freedom. This allows us reduce transport equations independent components Wigner function one scalar equation. To next-to-leading order $\ensuremath{\hbar}$, we find that contains both local nonlocal terms. show off-shell contributions cancel Our...

We derive Boltzmann equations for massive spin-1/2 fermions with local and nonlocal collision terms from the Kadanoff--Baym equation in Schwinger--Keldysh formalism, properly accounting spin degrees of freedom. The are expressed matrix-valued distribution functions, which building blocks quasi-classical parts Wigner functions. Nonlocal appear at next-to-leading order $\hbar$ sources polarization part functions pave way simulating spin-transport processes involving spin-vorticity couplings...

The relativistic treatment of spin is a fundamental subject which has an old history. In various physical contexts it necessary to separate the total angular momentum into orbital and contribution. However, such decomposition affected by ambiguities since one can always redefine part through so-called pseudo-gauge transformations. We analyze this problem in detail discussing most common choices energy-momentum tensors with emphasis on their implications, study vector invariant operator....

We derive relativistic dissipative spin hydrodynamics from kinetic theory featuring a nonlocal collision term using the method of moments. In this framework, components tensor are dynamical variables which obey relaxation-type equations. find that corresponding relaxation times determined by local part term, while contributes to Navier-Stokes terms in these equations motion. The timescales comparable those usual currents. Finally, limit Pauli-Lubanski vector receives contributions...

We propose a new theory of second-order viscous relativistic hydrodynamics which does not impose any frame conditions on the choice hydrodynamic variables. It differs from Mueller-Israel-Stewart by including additional transient degrees freedom, and its first-order truncation reduces to Bemfica-Disconzi-Noronha-Kovtun theory. Conditions for causality stability are explicitly given in conformal regime. As an illustrative example, we consider Bjorken flow solutions our equations identify...

We derive an expression for the tensor polarization of a system massive spin-1 particles in hydrodynamic framework. Starting from quantum kinetic theory based on Wigner-function formalism, we employ modified method moments which also takes into account all spin degrees freedom. It is shown that uncharged fluid determined by shear-stress tensor. In order to quantify this novel effect, provide formula can be used numerical calculations vector-meson alignment relativistic heavy-ion collisions.

We investigate the weak-interaction-driven bulk-viscous transport properties of npe matter in neutrino transparent regime. Previous works assumed that induced bulk viscosity correction to pressure, near beta equilibrium, is linear deviations from equilibrium charge fraction. show this not always true for (some) realistic equations state at densities between one and three times saturation density. This nonlinear nature perturbation around motivates a far-from-beta-equilibrium description...

We derive the set of inequalities that is necessary and sufficient for nonlinear causality linear stability first-order relativistic hydrodynamics with either a <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:mi>U</a:mi><a:mo stretchy="false">(</a:mo><a:mn>1</a:mn><a:msub><a:mrow><a:mo stretchy="false">)</a:mo></a:mrow><a:mrow><a:mi>V</a:mi></a:mrow></a:msub></a:mrow></a:math> conserved current or <e:math xmlns:e="http://www.w3.org/1998/Math/MathML"...

We calculate the contribution to polarization of $\Lambda$ hyperons in relativistic nuclear collisions at high energy from decays $\Sigma^*(1385)$ and $\Sigma^0$, which are predominant sources production besides primary component, as a function momentum. Particularly, we estimate longitudinal component mean spin vector azimuthal angle transverse plane, assuming that $\Sigma^*$ $\Sigma^0$ follow predictions local thermodynamic equilibrium fluid. Provided rapidity dependence around midrapidity...

A global equilibrium state of a spin polarized fluid that undergoes constant acceleration along the stream lines is described as solution recently introduced perfect-fluid hydrodynamic equations with 1/2.

We present the explicit expressions of different pseudo-gauge transformations for Dirac and Proca fields considering a general interaction term. The particular case with background electromagnetic field is also studied. Starting from quantum kinetic theory collisions derived Wigner-function formalism massive spin-1/2 spin-1 particles, we establish connection between pseudo-gauges relativistic spin hydrodynamics. physical implications various decompositions orbital angular momentum are discussed.

Rotating photon gas exhibits a chirality separation along the angular velocity which is manifested through generation of helicity and zilch currents. In this paper we study system using corresponding Wigner function construct elements covariant chiral kinetic theory for photons from first principles. The solved order-by-order in $\hbar$ unconstrained terms are fixed by matching with quantum field results. We further consider currents show that both manifestations transport originate Berry...

We prove that ideal chiral hydrodynamics, as derived from kinetic theory, is acausal and its initial-value problem ill posed, both in the linearized case around a local equilibrium solution also full nonlinear regime. Therefore, such theory cannot be used to determine how anomaly affects hydrodynamic evolution. show these fundamental issues can fixed by using different definitions (frames) for fields. This leads causal of hydrodynamics where vorticity strength constrained coefficient encodes anomaly.

In the study of spin-polarization phenomena in heavy-ion collisions, it is typically assumed that final-state particles are polarized through thermal vorticity and shear. this sense, polarization a effect. Here, we propose different mechanism. We postulate collision spin-carrying nucleons generates an initial transverse spin density, inducing net QCD fireball along random direction. If conserved throughout evolution fireball, should exhibit measurable polarization. Within wounded nucleon...

We compute the radius of convergence linearized relativistic hydrodynamic expansion around a nontrivially rotating strongly coupled $\mathcal{N}=4$ super-Yang-Mills plasma. Our results show that validity hydrodynamics is sustained and can even get enhanced for conformal field theory (CFT) in state. Analytic equations dispersion relations transport coefficients plasma as function their values at rest are given.

Abstract The thermal plasma filling the early universe generated a stochastic gravitational wave background that peaks in microwave frequency range today. If graviton production rate is expressed as series fine-structure constant, α , and temperature over Planck mass, T 2 / m pl then lowest-order contributions come from single (∼ αT ) double 4 via → scatterings. We show Standard Model, single-graviton dominates if maximal smaller than × 10 18 GeV. This justifies previous calculations which...

We present a derivation of quantum kinetic theory for massive spin-1 particles from the Wigner-function formalism up to first order in an $\ensuremath{\hbar}$-expansion, including general interaction term. Both local and nonlocal contributions are computed covariant fashion. It is shown that, $\ensuremath{\hbar}$, collision term takes same form as case spin-$1/2$ particles.