Paul Dirac explained the properties of subatomic particles with this equation:
(iγᵝ∂ᵦ - m)ψ = 0
the variable i stands for the imaginary unit,
γᵝ stands for Dirac matrices (or gamma matrices). They are 4x4 matrices that encode the spin of the particle.
∂ᵦ is the partial derivative with respect to space and time.
m stands for the mass of the particle, while ψ describes the state of the particle.
Putting it all together, this was able to predict antimatter, and solved a problem in quantum physics, explaining its spin, or angular momentum of 1/2.