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How was the positron predicted before it was discovered?

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subatomic particle The Large Hadron Collider (LHC), the world's most powerful particle accelerator. At the LHC, located underground in Switzerland, physicists study subatomic particles.

The positron was predicted through the mathematical development of the Dirac wave equation in 1928, which successfully integrated special relativity into quantum mechanics to describe the electron.12

While the equation was a major success, it yielded solutions corresponding to negative energy states that initially seemed to lack physical meaning. In 1930, P.A.M. Dirac proposed that these states represented "holes" in a sea of negative-energy electrons. He initially hypothesized these holes might be protons, but it was soon demonstrated that a hole must possess the same mass as an electron.12

Consequently, in 1931, Dirac concluded that his theory implied the existence of a previously unknown particle with the same mass as an electron but an opposite electrical charge. This theoretical "antielectron" was confirmed in 1932 when Carl David Anderson discovered the positron in cosmic ray studies, marking a triumph for the predictive power of mathematical formalism in physics.12