P.R. Holland

What happens in a spin measurement

Abstract An objective account of a Stern-Gerlach experiment performed with spin- 1 2 particles is developed in which the particles have well-defined and continuous trajectories and spin vectors, through the causal interpretation of the Pauli equation.

A causal account of non-local Einstein-Podolsky-Rosen spin correlations

We give a causal interpretation of a double Stern-Gerlach experiment on the basis of spacetime solutions to the Pauli equation. For an initial singlet state, we determine the continuous particle trajectories and spin vector orientations. The graphical results exemplify how non-local actions of the quantum potential and quantum torque give rise to a correlated evolution of dynamical variables. 1. The causal description of the Pauli spinor

Elimination of negative probabilities within the causal stochastic interpretation of quantum mechanics

Abstract Negative probabilities resulting from the Klein-Gordon equation are eliminated from quantum theory within the stochastic interpretation of quantum theory (SIQM) for spin-zero particles. The assumption of real physical paths in E 4 implies that only particles (antiparticles) of positive energies move forward in time with positive probability densities.

A quantum potential approach to spin superposition in neutron interferometry

Abstract The causal interpretation of the Pauli equation is shown to provide an understanding of spin superposition in neutron interferometry in terms of well-defined individual particle trajectories with continuously variable spin vectors.

Stochastic physical origin of the quantum operator algebra and phase space interpretation of the Hilbert space formalism: The relativistic spin zero case

Abstract Based on a recent association of quantum observable algebra with stochastic processes in the frame of the causal stochastic interpretation of quantum mechanics, a relativistic Hilbert space is defined for the Klein-Gordon case. It is demonstrated that unitary transformations in Hilbert space reflect canonical transformations in the associated phase space, manifesting thus an underlying symplectic structure.

Relativistic Wigner function as the expectation value of the PT operator

Abstract We define for the covariant relativistic Schrodinger equation a Hilbert space structure and generalize the Wigner-Moyal formalism to this case. We show how as a result the work of Royer may be generalized to express the relativistic Wigner function as the expectation value of the PT operator, and give an interpretation for the appearance of negative densities in terms of antiparticles.

On the association of positive probability densities with positive energies in the causal theory of spin 1 particles

Abstract We show how according to the causal interpretation of quantum mechanics the solutions to the Proca equation for a massive spin 1 particle in well-behaved external fields may be separated into positive and negative energy motions associated respectively with positive and negative probability densities. This strengthens a result provable using the hamiltonian method.

Positive energy/positive probability density association in second-order fermion theories

Abstract It is shown that in the frame of second-order fermion theories positive energy densities are associated with positive probability densities by using the symmetry properties of the Feynman-Gell-Mann equation, in agreement with the basic assumptions of the stochastic interpretation of quantum mechanics. A relation to the solutions of the Dirac equation is furthermore established.

The quantum potential and signalling in the Einstein-Podolsky-Rosen experiment

According to the causal interpretation of quantum mechanics, one can precisely define the state of an individual particle in a many-body system by its position, momentum, and spin. It is shown in the EPR spin experiment that the quantum torque brings about an instantaneous change in the state of one of the particles when the other undergoes a local interaction, but that such a transfer of “information” cannot be extracted by any experiment subject to the laws of quantum mechanics.

Cosmology and the causal interpretation of quantum mechanics

Abstract We answer the objections raised recently by Tipler to the trajectory interpretation of quantum mechanics by analyzing in detail the scattering of a particle from a semi-transparent surface. We conclude that the notion of the “wavefunction of the universe” poses no particular problems for this interpretation.