Since the great Scottish scientist George Clerk Maxwell’s formulation of his electromagnetics theory in 1865, which formed one of the pillars of modern physics, researchers have made a long way towards a better understanding of electromagnetic fields. His work led to the unification of electric and magnetic field that was an analogous to Newton’s classical mechanics. The theory was based on an intrinsic property of every particle, i.e., electric charge. According to his equations, contrary to the electric charge, magnetic charge or isolated magnetic monopole could not exist. This is an obvious fact in our normal life. Every magnet has two poles, north and south, and the idea of isolated north and south poles seems meaningless; magnetic poles are always found in nature as coupled pairs. Well, this topic has been open to discussion for scientists who have long been researching for magnetic monopoles.
Prediction of the existence of magnetic monopoles
In 1931, the famed British physicist Paul M Dirac (1902-1984) predicted the possibility of the existence of magnetic monopoles in nature. Later work by other researchers showed that quantum theory allowed for such strange structures. In 1974, Polyakov and Hooft discovered that existence of magnetic monopoles was a result of the ideas on the unification of fundamental interactions in nature. Since then, this issue has been a great challenge of modern physics, and theories seek to prove that all forces in nature have a unified origin. Indeed, all grand unification models predict the existence of isolated magnetic charges in nature. The existence of even one magnetic monopole in nature is of extreme importance because it would lead to profound changes in current physical theories as well as our understanding of the universe. They are predicted to be very massive stable particles that were originally produced in large numbers immediately after the Big Bang.
During the past 80 years, based on the predictions of quantum mechanical theories on the existence of magnetic monopoles, a tremendous amount of work and research has been made to find them, but it was not until some clues to the existence of this mysterious object were found during the last years. The following are a few of recent discoveries that can finally end up to a definite answer to this mysterious particle.
In October 18, 2010, a team of researchers from Paul Scherrer Institute and University College of Dublin reported that for the first time moving magnetic monopoles were photographed. The research led by Laura Heyderman and Hans-Benjamin Braun was designed to form magnetic monopoles as an assembly of nano-magnets and take their photos by a microscope. The idea worked and researchers managed to indeed observe lab created monopoles at room temperature as was predicted by Dirac.
On April 20, 2013, London Centre for Nanotechnology (LCN) scientists also reported that the existence of magnetic monopoles might be real. In their researches, they managed to find them in a material called “spin ice”. This was not a definite confirmation to free magnetic monopoles, yet it was a big step towards it. A series of papers about the experiment prove that certain materials like “icy spin” could develop within themselves these strange particles.
In 2014, based on an earlier suggestion or two Alto university researchers, Ville Pietilä and Mikko Möttönen about a practical method of creating a magnet monopole, another research was conducted and indeed, their method came out to be successful. In Jan. 29, 2014 edition of Nature magazine, it was reported that for the first time a team of researchers from Amherst College and Alto university in Finland had successfully created a synthetic magnetic pole under lab condition. The discovery was of extreme important for the physics community in that it paved the way for more research towards the ultimate discovery of natural magnetic monopoles.
It is still a long way before natural magnetic poles can be discovered. The existence of a magnetic charge in quantum mechanics provides an explanation for charge quantization in nature.
Besides its theoretical importance and its breaking impact on our understanding of the universe and its creation immediately after the Big Bang, the discovery of magnetic poles is also of great importance for the technology. If the monopoles could be controlled and manipulated like electric charges, then it would open a new era for the modern technology. It is predicted that its immediate impact would be on digital as well as mass storage devices. As the researcher Hans-Benjamin Braun put it, “it is likely that the next generation of data storage media will be composed of isolated macrospins — like our nanomagnets.”
Image credit: Heikka Valja