Quantum information theoretic approach to the hard problem of consciousness.

Functional theories of consciousness, based on emergence of conscious experiences from the execution of a particular function by an insentient brain, face the hard problem of consciousness of explaining why the insentient brain should produce any conscious experiences at all. This problem is exacerbated by the determinism characterizing the laws of classical physics, due to the resulting lack of causal potency of the emergent consciousness, which is not present already as a physical quantity in the deterministic equations of motion of the brain. Here, we present a quantum information theoretic approach to the hard problem of consciousness that avoids all of the drawbacks of emergence. This is achieved through reductive identification of first-person subjective conscious states with unobservable quantum state vectors in the brain, whereas the anatomically observable brain is viewed as a third-person objective construct created by classical bits of information obtained during the measurement of a subset of commuting quantum brain observables by the environment. Quantum resource theory further implies that the quantum features of consciousness granted by quantum no-go theorems cannot be replicated by any classical physical device.

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