Simple solutions of relativistic hydrodynamics for cylindrically symmetric systems

Simple, self-similar, analytic solutions of 1+3-dimensional relativistic hydrodynamics are presented for cylindrically symmetric fireballs corresponding to central collisions of heavy ions at relativistic bombarding energies.     

Simple solutions of relativistic hydrodynamics for longitudinally expanding systems

Simple, self-similar, analytic solutions of 1+1-dimensional relativistic hydrodynamics are presented, generalizing Bjorken's solution to inhomogeneous rapidity distribution.     

Stable first-order particle-frame relativistic hydrodynamics for dissipative systems

We propose a stable first-order relativistic dissipative hydrodynamic equation in the particle frame (Eckart frame) for the first time. The equation to be proposed was in fact previously derived by the authors and a collaborator from the relativistic Boltzmann equation. We demonstrate that the equilibrium state is stable with respect to the time evolution described by our hydrodynamic equation in the particle frame. Our equation may be a proper starting point for constructing second-order causal relativistic hydrodynamics, to replace Eckart's particle-flow theory.     

New family of simple solutions of relativistic perfect fluid hydrodynamics

A new class of accelerating, exact and explicit solutions of relativistic hydrodynamics is found—more than 50 years after the previous similar result, the Landau–Khalatnikov solution. Surprisingly, the new solutions have a simple form, that generalizes the renowned, but accelerationless, Hwa–Bjorken solution. These new solutions take into account the work done by the fluid elements on each other, and work not only in one temporal and one spatial dimensions, but also in arbitrary number of spatial dimensions. They are applied here for an advanced estimation of initial energy density and life-time of the reaction in ultra-relativistic heavy ion collisions. New formulas are also conjectured, that yield further important increase of the initial energy density estimate and the measured life-time of the reaction if the value of the speed of sound is in the realistic range.     

Exact solutions of relativistic perfect fluid hydrodynamics for a QCD Equation of State

The half-life of the mirror $\beta$ decay of ³¹S has been measured at the IGISOL facility at the University of Jyv?skyl?. The value obtained is $T_{1/2}(^{31}S)=(2553.4\pm 1.8)$ ms, in agreement with previous measurements, but with a precision that is better by a factor of ten than the literature value previously adopted. When the new result is combined with the Q_EC value measured recently at JYFLTRAP, a precision of better than $10^{-3}$ is obtained for the ft value.     

Robust particle methods for relativistic hydrodynamics

In this paper we describe how the equations of relativistic fluid dynamics can be solved numerically using the particle method SPH.     

Canonical formulation of relativistic hydrodynamics

Canonical formulation of the relativistic theory of perfect fluids is given. As an introduction to this subject the canonical formalism for charged particles interacting with electromagnetic field is briefly discussed. Relativistic hydrodynamics is studied in several versions including hydrodynamics of charged fluids coupled to the electromagnetic field and ultrarelativistic hydrodynamics. Ultrarelativistic hydrodynamics is shown to be conformally invariant and several implications of conformal symmetry are discussed.     

A variational formulation of relativistic hydrodynamics

We combine Taub's and Ray's variational approaches to relativistic hydrodynamics of perfect fluids into another simple formulation.     

Induced anomalous current in relativistic hydrodynamics with chiral anomaly

We discuss the triangle anomalous hydrodynamics in the presence of an external magnetic field B ^??. Without loss of generality, we consider the case of a conserved vector current and non-conserved axial current. In order to ensure the positivity of the entropy production rate, two new terms proportional to the magnetic field B ^?? and the vorticity ?? ^??, which are associated with the Chiral Magnetic Effect and Chiral Vortical Effect in heavy ion collisions, need to be introduced. The transport coefficients of these new terms are also determined by the entropy principle.     

Nonextensive perfect hydrodynamics — a model of dissipative relativistic hydrodynamics?

We demonstrate that nonextensive perfect relativistic hydrodynamics (q-hydrodynamics) can serve as a model of the usual relativistic dissipative hydrodynamics (d-hydrodynamics) therefore facilitating considerably its applications. As an illustration, we show how using q-hydrodynamics one gets the q-dependent expressions for the dissipative entropy current and the corresponding ratios of the bulk and shear viscosities to entropy density, ζ/s and η/srespectively.      

Conformal symmetry of relativistic and nonrelativistic systems and AdS/CFT correspondence

The nonlinear realization of conformal so(2,d) symmetry for relativistic systems and the dynamical conformal so(2,1) symmetry of nonrelativistic systems are investigated in the context of AdS/CFT correspondence. We show that the massless particle in d-dimensional Minkowski space can be treated as the system confined to the border of the AdS_d+1 of infinite radius, while various nonrelativistic systems may be canonically related to a relativistic (massless, massive, or tachyon) particle on the AdS₂ × S^d−1. The list of nonrelativistic systems “unified” by such a correspondence comprises the conformal mechanics model, the planar charge-vortex and three-dimensional charge-monopole systems, the particle in a planar gravitational field of a point massive source, and the conformal model associated with the charged particle propagating near the horizon of the extreme Reissner-Nordström black hole.     

Extending the reach of hydrodynamics for relativistic heavy ion collisions

Recent and ongoing improvements to hydrodynamic treatments at RHIC are extending the physics reach of hydrodynamics, and improving the phenomenology. Here, the links between technological improvements and the extension of physics are emphasized.     

Internal symmetry of relativistic wave equations

The properties are considered of the internal symmetry of first-order relativistic wave equations on the basis of the Gel'fand-Yaglom approach. A sufficient condition is established for the existence of such a symmetry for free fields.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 16–18, July, 1991.     

Theory of symmetry for a rotational relativistic Birkhoff system

The theory of symmetry for a rotational relativistic Birkhoff system is studied. In terms of the invariance of the rotational relativistic Pfaff－Birkhoff－D'Alembert principle under infinitesimal transformations, the Noether symmetries and conserved quantities of a rotational relativistic Birkhoff system are given. In terms of the invariance of rotational relativistic Birkhoff equations under infinitesimal transformations, the Lie symmetries and conserved quantities of the rotational relativistic Birkhoff system are given.