Idea Ripper // ArchiveCards: 1555 [Live] | Updated: 2026-10-14
Card #c98IR // #c98Synthesis

The qubit can then optionally be measured, in which case either of the states |0⟩ and |1⟩ is observed, as the measurement apparatus detects through which slit the photon passes.

— In our words · Source: Quantum Computing (S. Herbert)

[Use when]

When "observe" is used as if it were free.

[Why it matters]

Measurement is apparatus choosing a slit story — not a gentle peek.

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