Physicist and mathematician — Rudolf Clausius (Köslin, 1822 – Bonn, 1888) was a German physicist and mathematician, among the founders of modern thermodynamics. He studied in Berlin and taught at several universities, including Zurich, Würzburg and Bonn. In 1850 he reformulated the second law of thermodynamics, and in 1865 he introduced the concept of entropy, coining the name from the Greek for “transformation”, establishing that in an isolated system it can only increase. He also contributed to the kinetic theory of gases, introducing the notion of the mean free path of molecules. His work laid the conceptual foundations for understanding the irreversibility of natural processes and the arrow of time.
Trivia
It is to Clausius that we owe the famous concise summary of the universe according to thermodynamics: “The energy of the universe is constant; the entropy of the universe tends to a maximum.”
Theories and contributions
- Second law (Clausius statement) — Heat cannot pass spontaneously from a colder body to a hotter one without external intervention.
- Entropy — Change in entropy for a reversible process: ; in an isolated system .
- Kinetic theory of gases — Introduced the concept of the mean free path of molecules into the kinetic model.
Appears in chapters
Linked atoms
6 linked atoms.
09 Teoria cinetica dei gas
- History: from the philosophical atom to the physical atom
- Derivation of the ideal gas law
- Atoms: from philosophical hypothesis to experimental evidence