Abstract
Photonic Dual-Aspect Consciousness (PDAC) asks whether felt moments leave a measurable trace in the brain’s ultra-weak light. The hypothesis is that brief biophotons co-vary with Selection, Binding, and Imprinting in a single conscious moment. Three tests are proposed: (1) a recognition-based delayed-choice task to see if familiarity nudges an even split; (2) a cortical-slice assay with single-photon cameras to detect a transient rise above a dark-corrected baseline; and (3) a compact photon-relation map (timing, phase, direction, polarisation) that beats shuffled baselines and reappears with recognition. Each met criterion scores 1 (PDAC score 0-3). A non-zero score would show that structure in brain light tracks reported experience, providing a practical way to gauge how quantum life might be.
Essay
Photonic Dual-Aspect Consciousness (PDAC) is a testable idea. When a moment is consciously felt, does the brain’s ultra-weak light carry a measurable trace of it? The moment is framed in three steps: Selection, Binding, and Imprinting. The aim is to see whether faint photons co-vary with those steps. Light is treated as a marker alongside electrical and chemical signalling, not as the state itself. This approach sits alongside Global Workspace and Integrated Information, which address when and how a state is conscious (Baars, 1988; Tononi, 2004). PDAC asks what appears in the brain's light at those times. Twistor geometry is used only as a short way to list photon patterns, such as arrival time, direction, phase and polarisation, not as a mechanism (Penrose, 1967; Huggett & Tod, 1994).
It is now possible to measure ultra-weak photon emission from neural tissue in light-tight rigs with single-photon avalanche diode (SPAD) cameras (Bruschini et al., 2019). Such emission has been imaged in vivo (Kobayashi et al., 1999). Quantum effects also appear in warm biology, for example, coherent energy transfer in photosynthesis and magnetoreception in birds (Engel et al., 2007; Ritz et al., 2000). Together, these facts set a plausible stage for testing PDAC.
Within this frame, a felt moment breaks into three steps:
1. Selection. A recognised cue (face, voice, place) may produce a small, preregistered tilt from an otherwise 50/50 split.
2. Binding. For a brief window, organised light helps hold the chosen pattern together. The optical signal rises above a dark-corrected shot-noise baseline. If counts allow, an optional antibunching check can be added.
3. Imprinting. During that window, relations in the photons (timing, phase, direction and polarisation) form a compact map that characterises the state and can reappear with recognition.
How quantum is life?
In PDAC, “how quantum” is a 0-3 score. One preregistered test per pillar; 1 if met, 0 otherwise.
Test 1: Selection (recognition-based delayed choice)
Does recognition bias an otherwise 50/50 quantum choice?
Two equal quantum paths. On each trial, one path is paired with a familiar, verified cue and the other with a matched novel cue. A deviation from 50/50 must appear only in familiar–novel blocks, not in novel–novel controls. Stimulus validation, masking/arousal matching, and hardware randomisation are preregistered (Ma, Kofler & Zeilinger, 2016).
Test 2: Binding
Does a structured input make cortical tissue emit more organised light than noise?
Brain slices receive a structured spatiotemporal input or a spectrally or temporally scrambled control while a SPAD camera records in a light-tight, calibrated rig. A brief rise above the dark-corrected baseline with the structured input earns the point. An antibunching check may be added as an optional criterion if counts permit.
Test 3: Imprinting
Do photon relations form a small, repeatable map that returns with recognition?
During a steady state, estimate a compact photon-relation map (timing, phase, direction, polarisation), compare it to shuffled baselines, then repeat on another day. The point is earned if the same map stands out and reappears more for recognised cues, with some cross-day stability.
PDAC score = 0-3
A clean zero sets an upper bound on how quantum the tested conditions are. A non-zero score means the brain’s faint light co-varies with experience: recognition nudges a 50/50 split (Selection), a brief organised rise appears during the moment (Binding), and a simple relation map reappears with recognition (Imprinting). If antibunching is confirmed with confidence, Binding qualifies as quantum-coherent. This does not claim that consciousness is light; only that the emission carries structure tied to experience and is detectable above a dark-corrected baseline.
Light here is a marker, a measurable companion to a felt state. Studying the brain's faint light tests whether the patterns that shape choices leave a trace. PDAC also asks whether some patterns persist, the lived shape of commitments, interactions and intentions, and whether, under the right conditions, they return as recognisable signatures.
The PDAC score captures how light co-varies with felt experience and offers a practical way to gauge how quantum life might be, pointing to where physics meets meaning in the brain’s own light.
Reference
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