The Halting Problem for Quantum Computers

TL;DR

This paper discusses the unresolved halting problem in quantum computing, highlighting the difficulties in determining when a quantum computation halts due to superposition and unknown stopping times.

Contribution

It clarifies that the halting problem for quantum computers remains unsolved and demonstrates the complexities involved in quantum computation halting behavior.

Findings

The halting problem for quantum computers is still unresolved.

Quantum superposition complicates the determination of halting times.

Different computational branches may halt at unknown, varying times.

Abstract

We argue that the halting problem for quantum computers which was first raised by Myers, is by no means solved, as has been claimed recently. We explicitly demonstrate the difficulties that arise in a quantum computer when different branches of the computation halt at different, unknown, times.