What Exactly Are Magnetic Monopoles?

In the field of physics, a monopole is envisioned as a particle that has only one magnetic pole—either a north or a south pole—without the counterpart. This idea can be quite challenging to grasp. When you split a conventional magnet, which has both poles, you end up with two smaller magnets, each still exhibiting both poles. In contrast, a monopole would manifest only one pole.

Why Is Their Existence So Crucial?

The quest for magnetic monopoles is pivotal for understanding symmetry in physics and for the development of Grand Unified Theories (GUTs). The presence of monopoles would suggest an inherent asymmetry in the electromagnetic field, as electric charges are always found in pairs—positive and negative. Discovering monopoles would challenge this notion and provide a foundation for theories that aim to unify the fundamental forces of nature.

One prominent theory in this pursuit is String Theory, which is actively searching for evidence of monopoles. Proving their existence could alleviate one of the significant criticisms of String Theory: its lack of testable predictions.

How Are Scientists Searching for Monopoles?

Given that magnetic monopoles are theorized to be massive yet interact very weakly with ordinary matter, their detection poses a considerable challenge. To uncover these elusive particles, researchers employ high-energy particle accelerators like the Large Hadron Collider (LHC). The premise is simple: if monopoles exist, they might be created during high-energy particle collisions.

To improve detection odds, many experiments are conducted in underground labs, shielding them from cosmic rays and other forms of background radiation that could obscure findings. Researchers are specifically looking for unique magnetic flux patterns that monopoles would generate in a magnetic field, utilizing specialized detectors for this purpose.

Additionally, high-energy cosmic rays interacting with Earth's atmosphere could potentially produce monopoles. To explore this, scientists have set up extensive arrays of detectors and observatories to analyze cosmic ray events, aiming to capture distinctive signatures that indicate monopole activity.

While no monopoles have been directly observed yet, their theoretical exploration has led to advancements in related fields, such as magnetic data storage and spintronics.

Citations

• Séances de la Société française de physique : Société française de physique, Société française de…