We consider the relativistic quantum mechanics of a two interacting fermions system. We first present a covariant formulation of the kinematics of the problem and give a short outline of the classical results. We then quantize the system with a general interaction potential and deduce the explicit equations in a spherical basis. The case of the Coulomb interaction is studied in detail by numeri...

Validity of the one-body current for the calculation of form factors in the point form of relativistic quantum mechanics B. Desplanques Abstract Form factors are calculated in the point form of relativistic quantum mechanics for the lowest energy states of a system made of two scalar particles interacting via the exchange of a massless boson. They are compared to the exact results obtained by u...

Using a relativistic constituent quark model based on point form of relativistic quantum mechanics with given set of degrees of freedom we investigate electroweak decays of the pion and ρ mesons. All free parameters of quark model (the mass u(d) -quark and parameters which determines the confinement scale) are fixed by using relevant experimental data. Leptonic Decays of Mesons in a PoincareCov...

In a framework of a stationary universe, time is de ned as a local and quantum-mechanical notion in the sense that it is de ned for each local and quantummechanical system consisting of a nite number of particles. In this context, the total universe consisting of an in nite number of particles has no time associated, and quantum mechanics and general theory of relativity are united consistently...

A method to develop physical theories of free particles in spacetime with the Galilean metric is presented. The method is based on a Principle of Analyticity and a Principle of Relativity, and uses the Galilei group of the metric. The first principle requires that state functions describing the particles are analytic and the second principle demands that dynamical equations for these functions ...

We express the unitary time evolution in non-relativistic regularized quantum electrodynamics at zero and positive temperature by a Feynman integral defined in terms of a complex Brownian motion. An average over the quantum electromagnetic field determines the form of the quantum mechanics in an environment of a quantum black body radiation. In this non-perturbative formulation of quantum elect...

In this paper, we develop a formalism describing in a relativistic way a system which consists of a classical and a quantum part being coupled. The formalism models one particle with spin 1 2 and it is a possible relativistic extension of the Event-Enhanced Quantum Theory. We postulate a covariant algorithm which plays the role of the standard reduction postulate in nonrelativistic quantum mech...

This paper is a progress report on the foundations for the canonical proper-time approach to relativistic quantum theory. We first review the the standard square-root equation of relativistic quantum theory, followed by a review of the Dirac equation, providing new insights into the physical properties of both. We then introduce the canonical proper-time theory. For completeness, we give a brie...

The system of two relativistic particles with einbein fields is quan-tized as a constrained system. A method of the introduction of the Newton–Wigner collective coordinate is discussed in presence of different gauge fixing conditions. Some arguments are involved in the favour of Lorents covariant gauge fixing conditions.

In this paper we consider non-relativistic quantum mechanics on a space with an additional internal compact dimension, i.e. R 3 ⊗S 1 instead of R 3. More specifically we study potential scattering for this case and the analyticity properties of the forward scattering amplitude, T nn (K), where K 2 is the total energy and the integer n denotes the internal excitation of the incoming particle. Th...