Wheeler's Delayed-Choice Experiment as an
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Wheeler's delayed-choice experiment appears to show that a choice made now retroactively determines whether a photon behaved as a wave or particle in the past — even billions of years ago in the cosmic version. This has been interpreted as evidence for retrocausality, the role of consciousness in collapsing the wave function, or the many-worlds interpretation. We show that none of these interpretations is required. In the information processing load framework established in Papers 4 and 7, the photon propagates with n ≈ 0 environmental interactions throughout its journey. Since n = 0 < n* for all physical photons, the condition C_wave < C_particle holds: the wave state is maintained for the entire propagation duration, regardless of whether that duration is nanoseconds or 10 Gyr. The experimenter's detector setting determines only n_detector at the moment of detection — not the photon's state during propagation. The interference visibility function is V = max(0, 1 − n_detector/n*): full interference when n_detector = 0, no interference when n_detector ≥ n*. We verify numerically that a photon from a quasar 10 Gly distant accumulates n ≈ 2.6 × 10⁶ CMB scatterings during propagation, while n* ≈ 82 for a 500 nm photon — confirming n << n* and wave state maintenance. The apparent retrocausality is a consequence of a misidentification: the question 'which path did the photon take during propagation?' presupposes a definite path during propagation, but in the load framework the photon was not in a path-definite state. There is no fact of the matter about the path during propagation. The detector choice at detection determines what question can meaningfully be asked — not what happened in the past.Wheeler's delayed-choice experiment appears to show that a choice made now retroactively determines whether a photon behaved as a wave or particle in the past — even billions of years ago in the cosmic version. This has been interpreted as evidence for retrocausality, the role of consciousness in collapsing the wave function, or the many-worlds interpretation. We show that none of these interpretations is required. In the information processing load framework established in Papers 4 and 7, the photon propagates with n ≈ 0 environmental interactions throughout its journey. Since n = 0 < n* for all physical photons, the condition C_wave < C_particle holds: the wave state is maintained for the entire propagation duration, regardless of whether that duration is nanoseconds or 10 Gyr. The experimenter's detector setting determines only n_detector at the moment of detection — not the photon's state during propagation. The interference visibility function is V = max(0, 1 − n_detector/n*): full interference when n_detector = 0, no interference when n_detector ≥ n*. We verify numerically that a photon from a quasar 10 Gly distant accumulates n ≈ 2.6 × 10⁶ CMB scatterings during propagation, while n* ≈ 82 for a 500 nm photon — confirming n << n* and wave state maintenance. The apparent retrocausality is a consequence of a misidentification: the question 'which path did the photon take during propagation?' presupposes a definite path during propagation, but in the load framework the photon was not in a path-definite state. There is no fact of the matter about the path during propagation. The detector choice at detection determines what question can meaningfully be asked — not what happened in the past. Keywords: delayed-choice experiment; Wheeler; retrocausality; information processing load; wave function collapse; quantum eraser; cosmic photon; weak measurement; n < n*; no consciousness required
•Apr 2, 2026•0 citations