Alternative interpretation of relativistic time-reversal and the time arrow

TL;DR

This paper proposes a new interpretation of relativistic time-reversal by introducing a 'time arrow' operator, suggesting the existence of an anti-universe with particles having opposite 'time arrow' values, potentially linked to dark matter.

Contribution

It introduces the concept of a 'time arrow' operator and the idea of an anti-universe, expanding the understanding of time-reversal beyond standard CPT transformations.

Findings

Particles in the anti-universe have opposite 'time arrow' values.

The anti-universe could be experimentally confirmed in laboratory settings.

The anti-universe may serve as a candidate for dark matter.

Abstract

It is well-known that the 4-rotation in the 4-dimensional space-time is equivalent to the CPT-transformation (C is the charge conjugation, P is the space inversion and T is the time-reversal). The standard definition of the T-reversal includes the change of the sign of time variable and replacement of the initial state of the particle (system of particles) by the final state and vice versa. Since the time-reversal operation changes the state of a particle, the particle's wave function cannot be the eigenfunction of the corresponding operator with a certain eigenvalue, as in the case of space parity. Unlike the CPT-transformation, the separate P, T, or C transformations cannot be reduced to any 4-rotation. The extended Lorentz group incorporates all the separate C, P, or T transformations which do not bring the time axis out of the corresponding light cone. The latter restriction is included in the standard definition of the time-reversal. In the present communication, we ignore this restriction. This allows to introduce the "time arrow" operator and characterize every particle by the new quantum number - "time arrow" value. The wave functions of all particles are eigenfunctions of this operator with eigenvalues equal to "time arrow" values. The particles with the "time arrow" values opposite to the "time arrow" value in our universe form another universe (anti-universe). The existence of anti-universe can be confirmed, in principle, by laboratory (atomic) experiments. The anti-universe may be also considered as a candidate to the role of dark matter.