Currently, light is seen as a vibration of the electromagnetic field, where according to Feynman:
“A real field is a mathematical function we use for avoiding the idea of action at a distance.” (Feynman, Leighton, & Sands, 1977) Vol. II, p15-7
Fields are common in physics today, e.g. the earth holds the moon in orbit by a gravitational field that exerts a force at every point in space, an electric field sets values at every point in space, and so on for other fields. Emboldened by the success of Faraday’s fields, physics began to invent fields that added what mathematics calls degrees of freedom to space.
Adding a degree of freedom to each point of space in effect adds a dimension to it, so adding many fields is like adding many dimensions to space. Gravity required one-dimension, electromagnetism two, the strong force three and the weak force two. These eight extra dimensions plus the three of space are why string theory needs eleven dimensions to work.
Yet the mathematics soon gets out of control because all these dimensions interact. Indeed, the main “discovery” of string theory’s attempt to explain the fields of physics mathematically was that it gives an almost unlimited number of possible architectures, over 10500 at least. This is why string theory doesn’t predict anything, so few scientists today see it as a fruitful approach. That a universe of eleven dimensions somehow collapsed into ours is a far-fetched idea akin to the multiverse story.
The alternative is some sort of field unification that reduces all the fields of physics to one. This is said to be a primary goal of physics today but the standard model only offers more fields not less, as its only answer to an unexplained effect is a new field. Quantum realism proposes that one field, the quantum field, generates all the effects we see.