On unorthodox qubits, with an application to the closed timelike curve problem

TL;DR

This paper proposes a modified quantum theory that omits the commutation constraint, enabling the modeling of closed timelike curves and providing a potential resolution to the grandfather paradox.

Contribution

It introduces unorthodox qubits within a modified quantum framework that relaxes the commutation constraint, addressing limitations in orthodox quantum theory related to closed timelike curves.

Findings

Unorthodox qubits can model systems with closed timelike curves.

The modified theory offers a solution to the grandfather paradox.

It challenges the necessity of the commutation constraint in quantum theory.

Abstract

In orthodox quantum theory the observables of spacelike separated quantum systems commute. I shall call this the commutation constraint. It severely limits quantum theory's explanatory power. For instance, the constraint cannot be met in the presence of closed timelike curves, leaving us with no choice but to rule them out by fiat. It also conflicts with Bekenstein's bound. Here I investigate a modified quantum theory, unorthodox quantum theory, which is different from the conventional theory only in its omission of this commutation constraint. In particular, I describe a system of unorthodox qubits and demonstrate how they can be used to model systems on closed timelike curves and how they allow for a solution of the grandfather paradox.