String theory is a purported theory of everything that physicists hope will one day explain…everything.
All the forces, all the particles, all the constants, all the things under a single theoretical roof, where everything that we see is the result of tiny, vibrating strings. Theorists have been working on the idea since the 1960s, and one of the first things they realized is that for the theory to work, there have to be more dimensions than the four we’re used to.
But that idea isn’t as crazy as it sounds.
Dimensional disaster
In string theory, little loops of vibrating stringiness (in the theory, they are the fundamental object of reality) manifest as the different particles (electrons, quarks, neutrinos, etc.) and as the force-carriers of nature (photons, gluons, gravitons, etc.). The way they do this is through their vibrations. Each string is so tiny that it appears to us as nothing more than a point-like particle, but each string can vibrate with different modes, the same way you can get different notes out of a guitar string.
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