On the speed of light in a vacuum in the presence of a magnetic field

TL;DR

This paper explores whether the speed of light in a vacuum is affected by the presence of a magnetic field, addressing a fundamental question with historical context but without providing experimental results.

Contribution

It reviews the historical and conceptual background of the question regarding light speed in a magnetic field, highlighting the lack of experimental evidence.

Findings

No experimental evidence yet for change in light speed due to magnetic fields

Historical analysis of the concept of vacuum and magnetism

Discussion of the philosophical implications of the question

Abstract

The nature of light, the existence of magnetism, the physical meaning of a vacuum are problems so deeply related to philosophy that they have been discussed for thousands of years. In this paper, we concentrate ourselves on a question that concerns the three of them: does light speed in a vacuum change when a magnetic field is present? The experimental answer to this fundamental question has not yet been given even if it has been stated in modern terms for more than a century. To fully understand the importance of such a question in physics, we review the main facts and concepts from the historical point of view.