Special Relativity ...
β=vcγ=1√1−β2ct′=γ(ct−βx)x′=γ(x−βct)
... and Quantum Mechanics.
ℏ22m∇2Ψ+V(r)Ψ=−iℏ∂Ψ∂t
Yes, you get both in one fun-filled semester!