A magnetic monopole is a hypothetical elementary particle that is a magnet with only one magnetic pole. It differs from the classical concept of a magnet that has two poles (north and south poles).

Magnetism observed in bar magnets and electromagnets comes from electric charges that carry a built-in angular momentum, rather than interaction of any elementary particles that carry a “magnetic charge”. Theories of electricity and magnetism (such as James Clerk Maxwell’s equations on electromagnetism) do not allow for magnetic monopoles.

Modern theories, such as the grand unified theory and superstring theory, have predicted the existence of magnetic monopoles, but as of 2018, no experimental or observational evidence has shown magnetic monopoles.

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