Clausius theorem

Etymology
Developed by German physicist and mathematician.

Proper noun

 * 1) A theorem stating that, for a thermodynamic system exchanging heat with external reservoirs and undergoing a thermodynamic cycle, $$\oint \frac{\delta Q}{T_{\text{surr}}} \leq 0,$$, where $$\delta Q$$ is the infinitesimal amount of heat absorbed by the system from the reservoir, and $$T_{\text{surr}}$$ is the temperature of the external reservoir (surroundings) at a particular instant in time.