High-density limit and inflation of matter

We prove rigorously that for a nonvanishing probability of having electrons in matter, with Coulomb interactions, within a sphere of radius , the latter, necessarily, grows not any slower than for large , where denotes the number of electrons. Thus it is not surprising that matter occupies so large a volume.     

Hydrodynamics of nuclear matter in the chiral limit

Using the Poisson bracket method, we construct the hydrodynamics of nuclear matter in the chiral limit, which describes the dynamics of all low-energy degrees of freedom, including the fluid-dynamical and pionic ones. The hydrodynamic equations contain, beside five Euler equations of relativistic fluid dynamics, N(2)(f)-1 second order equations describing propagating pions and N(2)(f)-1 first order equations describing the advection of the vector isospin charges. We present hydrodynamic arguments showing that the pion velocity vanishes at the second order phase transition at N(f) = 2.     

High-density limit of quasi-two-dimensional dipolar Bose gas

We consider a simple model of the quasi-two-dimensional dipolar Bose gas confined in the one-dimensional square well potential. All dipoles are assumed to be oriented along the confining axis. By means of hydrodynamic approach it is shown that the general structure of the low-lying excitations can be analyzed exactly. We demonstrate that the problem significantly simplifies in the high-density limit for which the density profile in the confined direction as well as the leading-order contribution to the ground-state energy and spectrum of elementary excitations are calculated. The low-temperature result for the damping rate of the phonon mode is also presented.     

Low-energy limit of chiral meson theory

Based on a phenomenologically successful effective chiral theory of pseudoscalar, vector, and axial-vector mesons, all the coefficients of the chiral perturbation theory are predicted. There is no new adjustable parameter in these predictions. Up to O(m ² _q) the formulas of the masses of the pseudoscalar mesons are the same as the ones obtained by ChPT. Received: 31 August 2000 / Accepted: 16 March 2001     

Quark matter nucleation in hot hadronic matter

We study the quark deconfinement phase transition in hot β-stable hadronic matter. Assuming a first order phase transition, we calculate the enthalpy per baryon of the hadron–quark phase transition. We calculate and compare the nucleation rate and the nucleation time due to thermal and quantum nucleation mechanisms. We compute the crossover temperature above which thermal nucleation dominates the finite temperature quantum nucleation mechanism. We next discuss the consequences for the physics of proto-neutron stars. We introduce the concept of limiting conversion temperature and critical mass M_cr for proto-hadronic stars, and we show that proto-hadronic stars with a mass M<M_cr could survive the early stages of their evolution without decaying to a quark star.     

The chiral limit of quenched lattice QCD

We investigate the low mass properties of our quenched QCD data for the range of beta values: 5.70, 6.00, 6.15 and 6.30. The chiral condensate, the ground-state meson spectrum and the scaling behaviour of various quantities are examined. A criterion for assessing at what value of the quark mass finite lattice effects become intolerable is suggested.     

Effective quark masses in the chiral limit

The behavior of effective, scale dependent quark masses in the chiral limit is studied using the operator product expansion. Their relation to current and constituent quark masses is clarified. Current correlation functions are examined as an example of separating effects of spontaneous and explicit chiral symmetry breaking.     

Partial restoration of chiral symmetry of vector mesons in hot hadronic matter: a possible signature of quark-gluon plasma

A φ meson is an excellent candidate to see the dynamical and critical phenomena at finite temperature of hadronic and quark matter which can be produced through relativistic nucleus-nucleus collisions. PHENIX Collaboration and Chairperson of the PHENIX-J Collaboration.     

Plasticity limit of metals during hot plastic deformation

A model of plasticity limit has been derived in the condition of hot plastic deformation, where dynamic recrystallization takes place, through the ratio between the rate of grain boundary sliding and the overall deformation rate. If fracture occurs preferentially at the grain boundaries we can replace the grain boundary deformation through the energy needed to cause fracture and express the temperature influence on the deformation stress. The plasticity limit is then the function of Zener-Hollomon parameter and deformation stress, where the exponent of deformation stress has a value of –4·3.     

Phase transition in hot pion matter

The equation of state for the pion gas is analyzed within the third virial approximation. The second virial coefficient is found from the ππ-scattering data, while the third one is considered as a free parameter. The proposed model leads to a first-order phase transition from the pion gas to a more dense phase at the temperature T_pt<136 MeV. Due to relatively low temperature this phase transition cannot be related to the deconfinement. This suggests that a new phase of hadron matter — ‘hot pion liquid’ — may exist.     

Hadrons in hot and dense matter

I discuss our current understanding of the properties of hot and dense hadronic matter in equilibrium and its excitation spectrum. The latter allows for an experimental study of matter under extreme conditions through ‘in-medium spectroscopy’.     

Spectral lines in hot dense matter

An algorithm is presented for the computation of photoabsorption cross sections at arbitrary temperature and matter density. The “average atom” model is refined to give an approximaate account for the different ionization stages. The broadening of spectral lines is accounted for in a simple approximation. Calculations are presented for the beryllium and germanium plasmas in the frequency region of spectral lines.     

Hadrons in dense and hot matter

Theoretical issues and perspectives of hadronic matter at high baryon density are discussed with focus on the restoration of chiral symmetry and observable consequences.Received: 30 September 2002, Published online: 22 October 2003PACS: 25.75.-q Relativistic heavy-ion collisions - 21.65. + f Nuclear matter     

Adiabatic index of hot dense stellar matter

We calculate the adiabatic index of hot dense stellar matter taking into account the full nuclear interaction in all possible channels.