The Nature of Consciousness: Consciousness, Life and Meaning

Quantum-gravitational Consciousness

Quantum effects at the level of the protein were studied by Michael Conrad ("Quantum Molecular Computing", 1992), who argued that the molecules inside each cell might be implementing a kind of quantum associative memory. The protein is, after all, a biomolecular information processing system (“Information processing in molecular systems”, 1972).

The British physicist Roger Penrose believes that consciousness must be a quantum phenomenon and that neurons are too big to account for consciousness. The US biologist Stuart Hameroff provided a better candidate: the "cytoskeleton". Inside neurons there is a "cytoskeleton", the structure that holds cells together, whose "microtubules" (hollow protein cylinders 25-nanometers in diameter) control the function of synapses. Penrose believes that consciousness is a manifestation of the “quantum cytoskeletal state” and its interplay between quantum and classical levels of activity. (Penrose implicitly attributes a special status only to the microtubules that are in the brain, but they are also ubiquitous among cells in the rest of the body and the same quantum argument could apply for microtubules in the foot).

The US neuroscientist Travis Craddock found "pi-resonance rings" in tubulin that may give rise to quantum effects. He imagines that a pi-resonance quantum underground pervades the core of living systems ("An investigation of the plausibility of stochastic resonance in tubulin dimmers", 2012). Other thinkers who credited quantum effects for the nature of life include Erwin Schroedinger ("What is Life", 1944), Albert Szent-Gyorgyi ("Introduction to Submolecular Biology", 1960), Alberte Pullman ("Quantum Biochemistry", 1963) and Herbert Froehlich ("Long-range coherence and energy storage in biological systems", 1968).

Hameroff speculates that consciousness may have predated life. Darwin's theory of evolution assumes that life evolved behavior to promote gene survival, but there were no genes in the "primordial soup". Darwin's theory of evolution, just like Physics, omits consciousness from the universe. Behavior, incidentally, is based on reward and punishment, which are normally understood as feelings. Hameroff speculates that maybe it was feelings that drove evolution from the "primordial soup" to our consciousness ("The Quantum Origin of life", 2017).

Reality emerges from the collapse or reduction of the wave function. But Penrose makes a distinction between "subjective" and "objective" reduction. Subjective reduction is what happens when an observer measures a quantity in a quantum system: the system is not in any specific state (the system is in a "superposition" of possible states) until it is observed, and the observation causes the system to reduce (or "collapse") to a specific state. This is the only reduction known to traditional Quantum Theory. This is the reduction that fascinated John Von Neumann and Eugene Wigner, who interpreted it as "consciousness causes reality", a hypothesis revived, starting in 2013, by the Australian philosophers David Chalmers and Kelvin McQueen ("Consciousness and the Collapse of the Wave Function", 2017). Objective reduction is, instead, a Penrose discovery, part of his attempt to unify Relativity Theory and Quantum Theory.

Superposed states each have their own space-time geometry. Under special circumstances, which microtubules are suitable for, the separation of space-time geometry of the superposed states (i.e., the "warping" of these space-times) reaches a point (the quantum gravity threshold) where the system must choose one state. The system must then spontaneously and abruptly collapse to that one state. So, objective reduction is a type of collapse of the wave function that occurs when the universe must choose between significantly different space-time geometries. Outside the brain this "self-collapse" may only result in a cacophony of proto-conscious events, but inside the brain the microtubules act as a "quantum computer" (Hameroff's own definition) that orchestrates protoconscious events into a stream of consciousness.

This "self-collapse" results in particular "conformational states" that regulate neural processes. These conformational states can interact with neighboring states to represent, propagate and process information. Each self-collapse corresponds to a discrete conscious event. Sequences of events then give rise to a "stream" of consciousness. Proteins somehow "tune" the objective reduction which is thus self-organized, or "orchestrated".

In other words, the quantum phenomenon of objective reduction controls the operation of the brain through its effects on coherent flows inside microtubules of the cytoskeleton.

In general, the collapse of the wave function is what gives the laws of nature a non-algorithmic element. Otherwise we would simply be machines and we would have no consciousness.

Penrose and Hameroff believe that "protoconscious" information is encoded in space-time geometry at the fundamental Planck scale and that a self-organizing Planck-scale process results in consciousness.

Hameroff even thinks that this theory can explain (and, philosophically speaking, rescue) free will because Penrose's "orchestrated object reduction" in microtubules, based on non-computable quantum information embedded in spacetime geometry, avoids algorithmic determinism ("How quantum brain biology can rescue conscious free will", 2012). It can also cause temporal non-locality, i.e. sending quantum information backwards, which would explain the observed delay in awareness of an action made famous by Benjamin Libet, Michael Gazzaniga and others.

Basically, Penrose believes in a Platonic scenario of conscious states that exist in a world of their own, and to which our minds have access. However, Penrose’s "world of ideas" is a physicist's world: quantum spin networks encode proto-conscious states and different configurations of quantum spin geometry represent varieties of conscious experience. Access to these states (consciousness as we know it) originates when a self-organizing process (the objective reduction), somehow coupled with neural activity, collapses quantum wave functions at Planck-scale geometry.

There is a separate mental world, but it is grounded in the physical world.

Consciousness is the bridge between the brain and space-time geometry.

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