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David E. Miller

Publications and source records attributed to David E. Miller.

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Motion of Confined Particles

We carry out numerical evaluations of the motion of classical particles in Minkowski Space $\mathbb{M}^{4}$ which are confined to the inside of a bag. In particular, we analyze the structure of the paths evolving from the breaking of the dilatation symmetry, the conformal symmetry and the combination of both together. The confining forces arise directly from the corresponding nonconserved currents. We demonstrate in our evaluations that these particles under certain initial conditions move toward the interior of the bag.

hep-ph

Confining forces

We discuss the forces on the internal constituents of the hadrons based on the bag model. The ground state of the hadrons forms a color singlet so that the effects of the colored internal states are neutralized. From the breaking of the dilatation and conformal symmetries under the strong interactions the corresponding currents are not conserved. These currents give rise to the forces changing the motion of the internal particles which causes confinement.

hep-ph

Trace Anomaly and Quasi-Particles in Finite Temperature SU(N) Gauge Theory

We consider deconfined matter in SU(N) gauge theory as an ideal gas of transversely polarized quasi-particle modes having a temperature-dependent mass m(T). Just above the transition temperature, the mass is assumed to be determined by the critical behavior of the energy density and the screening length in the medium. At high temperature, it becomes proportional to T as the only remaining scale. The resulting (trace anomaly based) interaction measure Delta=(e - 3P)/T^4 and energy density are found to agree well with finite temperature SU(3) lattice calculations.

hep-ph

Lattice QCD Calculation for the Physical Equation of State

In this report we consider the numerical simulations at finite temperature using lattice QCD data for the computation of the thermodynamical quantities including the pressure, energy density and the entropy density. These physical quantities can be related to the equation of state for quarks and gluons. We shall apply the lattice data to the evaluation of the specific structure of the gluon and quark condensates at finite temperature in relation to the deconfinement and chiral phase transitions. Finally we mention the quantum nature of the phases at lower temperatures.

hep-ph

Entropy for Diquarks in exotic Quark States

We discuss the quantum state structure on the basis of $SU(3)_c$ for some known exotic quark systems using a model which describes these particular states as highly correlated diquarks and antidiquarks. We are then able to calculate for a single colored diquark a finite von Neumann entropy from the quantum reduced density matrix, from which we explicitly evaluate the likelihood of certain arrangements of quark flavors in a given diquark. These results can be related to some recently experimentally found pentaquark systems as well as a possible model for the scalar mesons.

hep-ph

The effects of colored quark entropy on the bag pressure

We study the effects of the ground state entropy of colored quarks upon the bag pressure at low temperatures. The vacuum expectation values of the quark and gluon fields are used to express the interactions in QCD ground state in the limit of low temperatures and chemical potentials. Apparently, the inclusion of this entropy in the equation of state provides the hadron constituents with an additional heat which causes a decrease in the effective latent heat inside the hadronic bag and consequently decreases the non-perturbative bag pressure. We have considered two types of baryonic bags, $Δ$ and $Ω^-$. In both cases we have found that the bag pressure decreases with the temperature. On the other hand, when the colored quark ground state entropy is not considered, the bag pressure as conventionally believed remains constant for finite temperature.

hep-ph

Entropy for Colored Quark States at Finite Temperature

The quantum entropy at finite temperatures is analyzed by using models for colored quarks making up the physical states of the hadrons. We explicitly work out some special models for the structure of the states of SU(2) and SU(3) relating to the effects of the temperature on the quantum entropy. We show that the entropy of the singlet states monotonically decreases meaning that the mixing of these states continually diminishes with the temperature. It has been found that the structure of the octet states is more complex so that it can be best characterized by two parts. One part is very similar to that of the singlet states. The other one reflects the existence of strong correlations between two of the three color states. Furthermore, we work out the entropy for the {\it classical} Ising and the {\it quantum} XY spin chains. In Ising model the quantum (ground state) entropy does not directly enter into the canonical partition function. It also does not depend on the number of spatial dimensions, but only on the number of quantum states making up the ground state. Whereas, the XY spin chain has a finite entropy at vanishing temperature. The results from the spin models qualitatively analogous to our models for the states of SU(2) and SU(3).

hep-ph

Entanglement in condensates involving strong interactions

We look at two well known examples of interacting systems relating to condensed matter in which we put the strong interacting parameters. At high quark chemical potentials and low temperatures we study the entropy arising from the excitation in the BCS model of superconductivity and the Bose-Einstein condensation (BEC) of colored quark pairs. We compare it with the ground state entropy for a system consisting of two colored quarks. In the BCS model we found that the entropy strongly depends on the energy gap. Both for the very small values of the momenta as well as those much greater than the characterizing Fermi momentum $p_f$, the ground state entropy is dominant. For the BEC case we suggest a phenomenological model to build up colored bosonic quark pairs. Here the entropy entirely depends upon the short ranged repulsive interactions between the quark pairs and vanishes for large momenta.

hep-ph

The Effects of Quantum Entropy on the Bag Constant

The effects of quantum entropy on the bag constant are studied at low temperatures and small chemical potentials. The inclusion of the quantum entropy of the quarks in the equation of state provides the hadronic bag with an additional heat which causes a decrease in the effective latent heat inside the bag. We have considered two types of baryonic bags, $Δ$ and $Ω^-$. In both cases we have found that the bag constant without the quantum entropy almost does not change with the temperature and the quark chemical potential. The contribution from the quantum entropy to the equation of state clearly decreases the value of the bag constant.

hep-ph

Entropy for $SU(3)_c$ Quark States

We discuss the quantum state structure using the standard model for three colored quarks in the fundamental representations of $SU(3)_c$ making up the singlet ground state of the hadrons. This allows us to calculate a finite von Neumann entropy from the quantum reduced density matrix, which we explicitly evaluate for the quarks in a model for the meson and baryon states. Finally we look into the general effects and implications of entanglement in the $SU(3)_c$ color space.

hep-ph

Gluon condensates at finite temperature

We consider various special cases of gluon condensates at finite temperature. The gluon condensate for an ideal gas of gluons with a given vacuum expectation value is introduced for the sake of comparison with that calculated using the recent finite temperature lattice gauge simulations for a pure Yang-Mills SU(3) gauge theory at the known critical temperature. We extend this comparison using the high precision lattice data for two light dynamical quarks. The investigation of these three cases show some interesting differences arising from the strong interaction alone and in the presence of quarks. In this context we discuss some newer simulations for heavier quarks and other properties related to gluon condensation.

hep-ph

Anomalous Currents and Gluon Condensates in QCD at Finite Temperature

After a short description of the currents coming from the known conservation laws in classical physics, we look at some further cases which arise after quantization in relation to quantum chromodynamics (QCD) at finite temperature. In these cases, however, some basic changes appear with the anomalies. First we go into the relationship between the trace of the energy momentum tensor and the gluon condensate at finite temperature. Using the recent numerical data from the simulations of lattice guage theory we present the computational evaluations for the gluon condensates at finite temperature. Thereafter we discuss the effects of chiral symmetry breaking and its restoration at finite temperature through the chiral phase transition. In this context we investigate the properties of the gluon condensate in the presence of massive dynamical quarks using numerical data. Finally we put together these results with a discussion of the various anomalous currents and their relationship to our findings here.

hep-ph

The Gluon Condensate in QCD at Finite Temperature

We begin with the discussion of the relationship between the trace of the energy momentum tensor and the gluon condensate at finite temperatures. Using the recent numerical data from the simulations of lattice gauge theory for quantum chromodynamics(QCD) we present the computational evaluations for the gluon condensate. A short discussion of the properties of deconfinement and the implications on the high temperature limit are included. We also mention the case of the massive quarks where some of the properties of the condensate appear to change. We put together these results with some ideas related to the dilatation current. We draw the conclusion that the nature of the strong interactions implies that the thermodynamics of quarks and gluons never approach even at very high temperatures that of an ideal ultrarelativistic gas.

hep-ph

The Temperature Dependence of the SU(N) Gluon Condensate from Lattice Gauge Theory

An analysis of the temperature dependence of the leading contributions to the gluon condensate for SU(N) lattice gauge theory is presented using the data from recent Monte Carlo simulations. The gluon condensate is calculated directly from the new lattice calculations of the interaction measure. It is shown how these computations provide a simple picture for the melting of the condensate around the deconfinement temperature, and the fact that it is negative, and increases in magnitude, above Tc. We close with a discussion of the implications for full QCD of recent results from simulations including fermions.

hep-ph