40983341
Nucleus-nucleus multiplicity distributions and quantum chromodynamics.
A model for nucleus-nucleus multiplicity distributions is proposed and its relations with hadron-proton and hadron-nucleus multiplicity distributions are explored and compared with the experimental data. The values of the parameters are the same for all these processes and owe their origin to the quantum chromodynamical gluon bremsstrahlung mechanism. Some other consequences of the model are also analyzed and compared with the available experimental data.
120005715
Signals of quark-gluon plasma
Abstract Production and observation of a quark-gluon plasma (QGP) is one of the most ambitious goals of the ultrarelativistic heavy ion experiments being carried out at CERN's super proton synchrotron (SPS) and at Brookhaven's Alternating Gradient Synchrotron (AGS). Future experiments at Brookhaven's Relativistic Heavy Ion Collider (RHIC) and at CERN's Large Hadron Collider (LHC) will give a new dimension to this search. In this review, the physics of QGP is presented with particular emphasis on its promising signatures existing in the literature. We hope that the present survey will lead us to identify some unambiguous signatures of QGP before the advent of RHIC and LHC experiments.
120612824
On the Singh-Uddin-Kamal relation in the negative binomial distribution
Abstract The empirical relation between the parameters k and n of the negative binomial distribution (NBD) as proposed by Singh, Uddin and Kamal is shown to emerge from the concept of the stationary branching process. Further consequences of this relation are derived and compared with the experimental data.
115391521
QUARK GLUON PLASMA : CURRENT STATUS OF PROPERTIES AND SIGNALS
119366615
Anisotropic Bianchi Type-II Cosmological Models in Self-Creation Cosmology
Totally anisotropic Bianchi type-II cosmological solutions are presented in Barber's second self-creation theory of gravitation both in vacuum and in the presence of stiff-matter. The corresponding cosmological models have no finite singularity. The stiff-matter model gives essentially an empty universe for large time. Some physical and kinematical properties of the models are discussed.
120728280
Rescattering effects in three-particle final-state reactions
The phenomenological aspect of single-pion production in ..pi../sup -/p interaction is explored by considering the final-state interactions in a rescattering box-diagram approach. We predict the qualitative and the quantitative features expected from our model in angular and momentum distributions of final pions. The preliminary data available so far appear to support our theoretical predictions.
16619649
London relation and fluxoid quantization for monopole currents in U(1) lattice gauge theory.
We explore the mechanism of quark confinement in four-dimensional U(1) lattice gauge theory by measuring the color-magnetic current distribution from Dirac magnetic monopoles in the presence of a static quark-antiquark pair. Our results give the first direct evidence that the quarks induce a solenoidal current distribution that screens the color-electric flux of the quarks in an electric analogue of the Meissner effect in a superconductor. We show that the vacuum state of U(1) lattice gauge theory obeys both a dual version of the London equation and an electric fluxoid quantization condition.
36246455
The quasiopen string.
The quasiopen string in D dimensions is defined by the Nambu-Goto action and the boundary conditions (x'+x)(σ α ,τ)=V α (x'-x) (σ α ,τ), where σ=σ 1 and σ 2 denote the ends of the string, x'≡∂x/∂σ, and the V α (α=1,2) are real symmetric orthogonal matrices. (The usual open string corresponds to V 1 =V 2 =−1.) We impose Poincare invariance in d dimensions, d α ) jk =−δ jk for j,k ∈ Poincare sector and (V α ) jk =0 if only one of j,k belongs to the Poincare sector. Further quantization gives D=26 and a mass spectrum with a ground-state mass squared M G 2 =−(1−J i ||theta i ||(1-||theTa I ||)/4)/α', where ||theta i ||≤(½), exp(2iπtheta i ) are the eigenvalues of V 2 V 1 , and α' is the slope parameter in the string action. A choice of theta i giving a tachyon-free spectrum is thus possible if d≤10.
29912513
Quantum gravitational corrections to the functional Schrödinger equation.
We derive corrections to the Schr\"odinger equation which arise from the quantization of the gravitational field. This is achieved through an expansion of the full functional Wheeler-DeWitt equation with respect to powers of the gravitational constant. The correction terms fall into two classes: One describes the breakdown of the classical background picture while the other corresponds to quantum gravitational corrections for the matter fields themselves. The latter are independent of the factor ordering which is chosen for the gravitational kinetic term. If the total state evolves adiabatically, the only correction term that survives contains the square of the matter Hamiltonian. In the general case there are also smaller terms which describe a gravitationally induced violation of unitarity. The corrections are numerically extremely tiny except near the big bang and the final stages of a black hole. They are also of principle significance for quantum field theories near the Planck scale.
35249306
Quantum violation of stochastic noncontextual hidden-variable theories.
We formulate stochastic noncontextual hidden-variable theories. In such theories the hidden state λ specifies not definite values, but expectation values A − (λ), ... of observables A, ... and noncontextuality means that A − (λ) is independent of which other commuting observables commuting with A are measured together with A. We show via Bell inequalities that such theories conflict with quantum theory and propose a two-photon experimental test. We also show that for a single particle of spin (2 n −1)/2, quantum violation of classical noncontextuality grows exponentially with n.
22845460
Birkhoff's theorem for electromagnetic fields in a new scalar-tensor theory.
A result having formal similarity to Birkhoff's theorem in general relativity is proved in the presence of electromagnetic fields in a new scalar-tensor theory of gravitation proposed by Schmidt et al. for the special case when the scalar field is massless and independent of time.