M-theory

physics

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July 16, 2026

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M-theory is a theoretical framework in physics that attempts to unify all fundamental forces and particles, including gravity, into a single "theory of everything". It is an extension of string theory, which posits that subatomic particles are not point-like but rather tiny, one-dimensional vibrating strings.12

Key aspects of M-theory include:
* Unification: It aims to reconcile quantum mechanics with general relativity.13
* Dimensions: M-theory suggests the existence of 11 spacetime dimensions, with extra dimensions being curled up and undetectable.13
* Supersymmetry: It incorporates supersymmetry, a symmetry that relates particles with different spin properties, and predicts partner particles for known ones.132
* Branes: In addition to strings, M-theory includes higher-dimensional objects called branes.2

While M-theory is a vibrant area of research, it remains a mathematical construct as it has yet to be experimentally verified.1

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By the mid-1990s these and other obstacles were again eroding the ranks of string theorists. But in 1995 another breakthrough reinvigorated the field. Edward Witten of the Institute for Advanced Study, building on contributions of many other physicists, proposed a new…
Read More