A Quantum Twin Paradox

TL;DR

This paper introduces a quantum version of the twin paradox, highlighting how a covariant quantum theory with a global proper time can resolve discrepancies in cause-effect relations caused by relativistic quantum measurements.

Contribution

It proposes a novel quantum twin paradox scenario and suggests that a global proper time is necessary for resolving causality issues in covariant quantum theories.

Findings

Identification of a quantum twin paradox using local t axis

Resolution requires introducing a global proper time

Highlights causality discrepancies in relativistic quantum measurements

Abstract

The Classical Twin Paradox is widely dealt in literature and neatly resolved. In addition, it is also well known that, when looking at two systems which are boosted relative to each other, the concept of the simultaneous effect of a quantum measurement in space-time causes some discrepancies in the cause-effect behavior. However, these discrepancies have been thought not to cause any apparent paradox except for violating the Free-Will postulate. In this paper we suggest that using the local t axis, all over space, as the axis in which the quantum measurement is thought to be simultaneous, we do reach a kind of true "Twin Paradox". The resolution of this paradox requires the introduction of a global proper time into a covariant quantum theory.