According to a U Michigan prof:
Our observations to date push us in the direction of entertaining the existence of an Ur-theory of nature. Consider the fact that a left-handed electron has an electric charge of -1 under the electromagnetic force, a charge of 2 (a ‘spin charge’) under the weak gauge force, and a charge of 0 under the strong force. At the same time, the right-handed down quark has an electric charge of -1/3, a weak force charge of 0, and a strong force charge of 3 (a ‘3-dimensional unitary group charge’, though the mathematical details don’t need to be understood here). So, between these two particles, we have charges of 0, -1/3, -1, 2 and 3, etc for the different forces arranged in a particular manner. It’s a motley crew of jumbled-up numbers, which doesn’t seem to have much rhyme or reason to it. However, a school of mathematics known as group theory tells us that this is exactly the collection of charges that are needed to form a new grand unified particle: let’s call it P, which can be represented as P=(left-handed electron, left-handed neutrino, right-handed down quark).
Likewise, we can analyse more particles in the Standard Model, such as right-handed electrons, right-handed up quarks and left-handed up and down quarks. After many measurements, we find another set of willy-nilly values for the charges they display under all three gauge forces. But upon closer inspection using group theory mathematics, we find that those numbers also magically fit exactly into a single grand unified particle: W=(right-handed electron, left-handed down quark, right-handed and left-handed up quarks). It’s as though 10 very raggedy puzzle pieces scattered on the floor were pieced together to make a perfect circle.
It didn’t have to be this way. The charges of the elementary particles in our Universe could have been such that there was no way to unify any two or more of them into a single unified particle. It’s the combination of observational data and mathematics that offers us strong hints that the charges for elementary particles in the standard model aren’t arbitrary, but rather arise by virtue of being embedded into a grand unified theory framework.James Wells, “Unified Universe” at Aeon
Well, isn’t that an argument for God? Join the line.
But others say, the idea of such a theory is discredited.
See also: Columbia University mathematician Peter Woit offers a shrewd assessment of Stephen Hawking and pop physicsHawking was looking for a unified theory and Woit thinks the idea is pretty much discredited now: “We now live in an environment where the idea that there may be a deeper, more unified theory has become completely discredited, through the efforts of many, with Hawking playing an unfortunate part.”