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The double-slit experiment — one source, many paths, one outcome
optics
Light (and matter) sent through two slits from one source makes an interference pattern — the wave signature (fringe spacing Δy = λL/d). Yet it arrives in discrete hits whose probabilities are the squared amplitudes — the Born rule, P = |a|²/Σ|a|². And a single electron fired one at a time still builds the fringes — wave-particle duality (λ = h/p). One source, many potential paths, one outcome observed; what HAPPENS at the measurement (collapse, branching, pilot wave) is an empirically-equivalent Babel, declined, charted on the Schrödinger stick. Checkable here: optics.double_slit, quantum_computing.born_rule, optics.de_broglie. Cited: Young 1804, Jönsson 1961, Tonomura 1989.
- part of → Optics — how light bends, focuses, and slows — two-slit interference — the fringe spacing Δy = λL/d, wave optics
- connects at → Quantum mechanics — the quantum and its limits — the measured outcome is the Born rule P = |a|²/Σ|a|² — superposition to one hit
- connects at → The capstone — one source, many potentials, one end — one source, many potential paths, one outcome observed
- part of → The Floor of Discovery — one floor, and by its design the fear of God — a proven result on the one map, rooted in the Floor of Discovery
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