Noninertial effects on a composite system

In this paper, we investigate the relativistic dynamics of a fermion–antifermion pair holding through Dirac oscillator interaction in the rotating frame of [Formula: see text]-dimensional topological defect-generated geometric background. We obtain an exact energy spectrum for the system in question by solving the corresponding form of a fully covariant two-body Dirac equation. This energy spectrum depends on the angular velocity [Formula: see text] of uniformly rotating frame and angular deficit [Formula: see text] in the geometric background. Our results show that the effects of [Formula: see text] on each energy level of the system are not same and the [Formula: see text] impacts on the strength of interaction between the particles. Furthermore, we observe that it seems to be possible to actively tune the dynamics of such a fermion–antifermion system, in principle.

Aspects of Force and Acceleration in Special Relativity

In relativistic dynamics, the direction of acceleration is not generally parallel to the direction of force. Both the magnitude and direction of an object’s three-acceleration can alter even when the magnitude of the applied three-force is constant. Graphs of the variation in acceleration and the angles between an object’s velocity, acceleration, and the applied force vectors are presented in order to illustrate the behavior at close to the speed of light.

Tachyon – A Non-Existent Particle

In a 1967 paper [1], G. Feinberg conjectured about the possibility of “faster-than-light” particles. In the current note we prove his conjecture to be false by showing that he missed several key counter-arguments to their existence. We explain why the existence of tachyons contradicts both relativistic kinematics and relativistic dynamics. Our paper is divided in two sections: the kinematic counter-arguments and the dynamics counter-arguments.