The Status of the Wave Function in Dynamical Collapse Models

No Heading The idea that in dynamical wave function collapse models the wave function is superfluous is investigated. Evidence is presented for the conjecture that, in a model of a field theory on a 1+1 lightcone lattice, knowing the field configuration on the lattice back to some time in the past, allows the wave function or quantum state at the present moment to be calculated, to arbitrary accuracy so long as enough of the past field configuration is known.     

Decoherence and Wave Function Collapse

The possibility of consistency between the basic quantum principles of quantum mechanics and wave function collapse is reexamined. A specific interpretation of environment is proposed for this aim and is applied to decoherence. When the organization of a measuring apparatus is taken into account, this approach leads also to an interpretation of wave function collapse, which would result in principle from the same interactions with environment as decoherence. This proposal is shown consistent with the non-separable character of quantum mechanics.     

Gravity-Related Wave Function Collapse

The gravity-related model of spontaneous wave function collapse, a longtime hypothesis, damps the massive Schrödinger Cat states in quantum theory. We extend the hypothesis and assume that spontaneous wave function collapses are responsible for the emergence of Newton interaction. Superfluid helium would then show significant and testable gravitational anomalies.     

The Wave Function Collapse as an Effect of Field Quantization

It is pointed out that ordinary quantum mechanics as a classical field theory cannot account for the wave function collapse if it is not seen within the framework of field quantization. That is needed to understand the particle structure of matter during wave function evolution and to explain the collapse as symmetry breakdown by detection. The decay of a two-particle bound s state and the Stern-Gerlach experiment serve as examples. The absence of the nonlocality problem in Bohm’s version of the EPR arrangement favours the approach described.     

Nonlinearity of Quantum Mechanics and Solution of the Problem of Wave Function Collapse

The problem of the wave function collapse(a problem of measurement in quantum mechanics) is considered.It is shown that it can be solved based on quantum mechanics and does not require any additional assumptions or new theories. The particle creation and annihilation processes, which are described based on quantum field theory, play a key role in the measurement processes. Superposition principle is not valid for the system of equations of quantum field theory for particles and fields, because this system is a non-linear. As a result of the creation(annihilation) of a particle,an additional uncertainty arises, which "smears" the interference pattern. The imposition of such a large number of uncertainties in the repetitive measurements leads to the classical behavior of particles. The decoherence theory also implies the creation and annihilation of particles, and this processes are the consequence of non-linearity of quantum mechanics. In this case, the term "collapse of the wave function" becomes a consequence of the other statements of quantum mechanics instead of a separate postulate of quantum mechanics.     

Nonlinearity of Quantum Mechanics and Solution of the Problem of Wave Function Collapse

The problem of the wave function collapse (a problem of measurement in quantum mechanics) is considered. It is shown that it can be solved based on quantum mechanics and does not require any additional assumptions or new theories. The particle creation and annihilation processes, which are described based on quantum field theory, play a key role in the measurement processes. Superposition principle is not valid for the system of equations of quantum field theory for particles and fields, because this system is a non-linear. As a result of the creation (annihilation) of a particle, an additional uncertainty arises, which "smears" the interference pattern. The imposition of such a large number of uncertainties in the repetitive measurements leads to the classical behavior of particles. The decoherence theory also implies the creation and annihilation of particles, and this processes are the consequence of non-linearity of quantum mechanics. In this case, the term "collapse of the wave function" becomes a consequence of the other statements of quantum mechanics instead of a separate postulate of quantum mechanics.     

相对论重离子碰撞与夸克物质

介绍了相对论重离子碰撞与夸克物质研究领域的有关最新进展.讨论了QCD热力学与量子输运理论,对于与QCD相变紧密联系的几个热点问题作了评述,最后分析了该研究领域在近期发展前景.     

Relativistic Heavy Ion Collisions and Quark Matter

The recent progress in the field of relahvistic heavy ion collisions and quark matter is reviewed. Especially, the QCD thermodynamics, quantum transport theory, and some hot topics related to the QCD phase transitions are analyzed in detail. The outlook for thes field is also briefly discussed.     

Relativistic Wave Equations and Compton Scattering

The recently proposed eight-component relativistic wave equation is applied to the scattering of a photon from a free electron (Compton scattering). It is found that in spite of the considerable difference in the structure of this equation and that of Dirac the cross section is given by the Klein–Nishina formula.     

Relativistic Wave Equations and Hydrogenic Atoms

The transition probabilities for the components of both the Balmer and Lyman -lines of hydrogenic atoms are calculated for the nonrelativistic Schrödinger theory, the Dirac theory, and the recently developed eight-component (8-C) formalism. For large Z it is found that all three theories give significantly different results.     

High-Speed Cylindrical Collapse of Type-I Matter

In this paper, the cylindrical symmetric gravitational collapse with anisotropic pressure has been investigated using high-speed approximation scheme. The collapsing speed of the fluid is assumed to be very large. To see the effects of pressure, we have used the equations $ \sqrt{p_{R}/\rho}=k$ and $\sqrt{p_{T}/\rho}=w$ of states for radial pressure and tangential pressure, respectively. It is observed that if the ratios of both pressures, that is, tangential and radial pressures, to energy density are bounded from below by some positive value, there arise two possibilities depending on whether 1?+?k ²???2 w ²?>?0 or 1?+?k ²???2w ²?<?0. For 1?+?k ²???2 w ²?>?0, the high-speed approximation scheme fails, while for 1?+?k ²???2 w ²?<?0, the high-speed approximation works. For vanishing w and k, the high-speed scheme does not break down, and, as a result, a naked singularity forms in this case. For p _T ?=?p _R ?=?p, all the results reduce to the perfect fluid case obtained by Nakao and Morisawa (Prog Theor Phys 113:73, 2005).     

Construction of Coarse-Grained Models by Reproducing Equilibrium Probability Density Function

The present work proposes a novel methodology for constructing coarse-grained(CG) models, which aims at minimizing the difference between CG model and the corresponding original system. The difference is defined as a functional of their equilibrium conformational probability densities, then is estimated from equilibrium averages of many independent physical quantities denoted as basis functions. An orthonormalization strategy is adopted to get the independent basis functions from sufficiently preselected interesting physical quantities of the system. Thus the current method is named as probability density matching coarse-graining(PMCG) scheme, which effectively takes into account the overall characteristics of the original systems to construct CG model, and it is a natural improvement of the usual CG scheme wherein some physical quantities are intuitively chosen without considering their correlations. We verify the general PMCG framework in constructing a one-site CG water model from TIP3 P model. Both structure of liquids and pressure of the TIP3 P water system are found to be well reproduced at the same time in the constructed CG model.     

Rodrigues' Formula for the Radial Wave Function in a Relativistic Model of the Oscillator

For the polynomial part of the radial wave function in a spherically symmetric quasipotential model of the oscillator, formulated in the relativistic configurational r-representation, the connection with the dual Hahn polynomials is found and a finite difference analogue of the Rodrigues' formula is obtained.     

On the Gravitational Collapse in Relativistic Theories of Gravitation

Following Einstein, we consider a simple model of a star, namely a spherically symmetric distribution of particles which are all moving along circular orbits around the center of the particle cluster. According to arguments given by Einstein, Laue, Treder and others, the existence of stationary circular motions for all values of r can be considered as a necessary condition for all collapse-free relativistic (classical) theory o gravitation. The discussion shows that, assuming the validity of the weak principle of equivalence and the principle of causality, one has to consider theories with a g₀₀-function different from the Einstein-Schwarzschild one. We discuss some g₀₀ types and show that our point of view leads in the direction of gravitational equations with a cut-off length.     

Non-Spherical Gravitational Collapse of Strange Quark Matter

We study the non-spherical gravitational collapse of the strange quark null fluid. The interesting feature which emerges is that the non-spherical collapse of charged strange quark matter leads to a naked singularity whereas the gravitational collapse of neutral quark matter proceeds to form a black hole. We extend the earlier work of Harko and Cheng [Phys. Lett. A 266 （2000） 249] to the non-spherical case.