Physics

Spacetime

Mathematical physics

Unification

Programming language

Theoretical physics

Computer science

Quantum mechanics

Kaluza–Klein theory

Classical mechanics

Electromagnetism

International Journal of Modern Physics D

Revised translation of Kaluza's historic 1921 paper, "Zum Unit\"atsproblem der Physik," on 5-dimensional spacetime, used to unify gravity and electromagnetism. This version is based, in part, on a 1984 translation provided by T. Muta, but revised and formatted using LaTeX to closely match the original paper in appearance and pagination. Kaluza's original notation is restored.

On the Unification Problem in Physics