Early attempts to merge quantum mechanics with special relativity involved the replacement of the Schrodinger equation with a covariant equation such as the Klein-Gordon equation or the Dirac equation.

• 早先的努力就是将量子力学与涉及具有协变式方程诸如开尔因-戈登方程或迪拉克方程的薛定谔方程代换的狭义相对论统一起来。