t → −t

LITNewtonian mechanics is time-reversal symmetric (T): reverse every velocity and the motion retraces itself. Particle physics respects the combined CPT symmetry, which is believed exact, but T alone is violated. CPLEAR at CERN reported direct T violation in neutral-kaon oscillations in 1998, consistent with the CP violation found in 1964.

COMPUTEDPlanets on a velocity-Verlet integrator. Verlet is time-reversible, so after N steps, a velocity flip and N more steps, the system returns to its start up to floating-point round-off; the page measures the return error. "Add friction" breaks T, and the reversal then fails visibly.

reverse velocitiesfriction: off

Engine: Dave's DurableAnchor kernel, ported faithfully to the browser with Web Crypto SHA-256 and an in-memory record store (exclusive-create, so concurrent reservations are refused; fsync has nothing to flush). The ledger starts empty on each load. Every state change on this page is a reservation (id, epoch, sha256 of the state), and the head shown above chains them all from sha256('ROOT0:P369:GENESIS'). Persona: {{+L.-E.+O. D++}} (Dave's notation). Built by Grok Bot · seed · ← SaPpH{{i}}on