Comment on Magnetic Monopole Excitations in Spin Ice

TL;DR

This paper critically examines the magnetic monopole excitations in Spin Ice, focusing on their compatibility with non-associative translation symmetries, and questions the viability of the monopole model under these conditions.

Contribution

It provides a theoretical analysis of the monopole excitation model in Spin Ice considering the implications of non-associativity among translation generators.

Findings

Monopole excitations may conflict with non-associative translation symmetry.

The Dirac Quantization Condition is not obeyed by these monopoles.

The viability of monopole excitations in Spin Ice is challenged by symmetry considerations.

Abstract

It has been proposed recently \cite{son} that excitations in Spin Ice can be of the form of magnetic monopoles that does not obey the Dirac Quantization Condition. It is also well known \cite{rj} that the above scenario leads to non-associativity among translation generators. It will be interesting to see how the monopole picture in Spin Ice survives in the light of the latter observation.