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Thermodynamics — the arrow and the one end
thermodynamics
The four laws. The first law is energy conservation (Noether's energy, now counting heat and work). The second law - entropy never decreases - is the one place physics is not time-reversible: the arrow of time, the one-way flow, the engine of 'the story ends the same way' (of the many microstates almost all reach the one maximum-entropy macrostate). Four pillars rest on the floors already seeded: the first law (on Noether), the second law (on the capstone), statistical mechanics (on the Hamiltonian), and entropy = information (on the instruments). The stick (stick_thermodynamics_the_arrow_and_the_one_end) seals the Carnot bound and the first-law balance; the second-law/Landauer and Boltzmann/Bekenstein seals are cited (tools/seed_thermodynamics.py).
- has part → The first law — energy is conserved — a law of thermodynamics (The first law)
- has part → The second law — entropy increases, the arrow, the one end — a law of thermodynamics (The second law)
- has part → Statistical mechanics — many microstates, one macrostate — a law of thermodynamics (Statistical mechanics)
- has part → Entropy is information — Boltzmann, Shannon, Landauer — a law of thermodynamics (Entropy is information)
- part of → The Floor of Discovery — one floor, and by its design the fear of God — the arrow of time on the one map
- connects at → Reaction direction — Gibbs and the second law — Delta G = Delta H - T Delta S decides which reactions run - the second law
- connects at → Equilibrium — Delta G = -RT ln K — the equilibrium constant is set by the free energy: Delta G = -RT ln K
- connects at → Metabolism — life runs on free energy — life is a local entropy decrease paid for globally - the second law, not broken
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