"In short, Lisi's paper tries to find a mathematical way to unite the interactions of all the particles in the universe, from force-carrying particles called bosons to fermions like electrons and quarks, which combine to make up matter.

The most agreed-upon theory to date — the Standard Model of particle physics — explains the interactions of matter with three of the four fundamental forces of nature: electromagnetism, the strong nuclear force (which binds the parts of a nucleus together), and the weak nuclear force (which allows for the radioactive decay of particles).

Where it's come up short is in explaining the fourth force: gravity. For the 30 years since the Standard Model was proposed, scientists have come up with a number of theories to unite the gravity of Einstein's theory of general relativity with the Standard Model, including string theory, which reduces the forces and matter of the universe to tiny one-dimensional filaments called strings that vibrate in 10 dimensions.

But critics of String Theory, Lisi included, argue it is virtually untestable and bears no resemblance to the world we live in. As Lisi writes in his paper: "A successful description of nature should be concise, elegant, unified mathematical structure consistent with experience."

Lisi's theory attempts to explain the relationship between the particles of the universe with the points on a complex, eight-dimensional mathematical pattern called E8."