Margolus–Levitin theorem

The Margolus - Levitin theorem describes the theory of quantum computing the fundamental physical limit of the speed of state changes and thus indirectly the computing power of a computer. It was derived from Norman Margolus and Lev B. Levitin.

The limit is 1033 operations per Joule at about 3 ×. The value is obtained from the consideration of one degree of freedom:

Theorem is also in other branches of the physics of interest, for example, by the connection with the holographic principle.