Timescales for consciousness
Quantum no-go theories and consciousness
Danko Georgiev, Kanazawa University, Japan
Springer Science+Business Media, 14 December 2012
In looking at the possible physical underpinnings of neuroscience, the author contrasts what is for consciousness studies the still dominant Newtonian orthodoxy of deterministic causes and effects, with quantum physics, in which there is a multitude of potential outcomes, rather than a single determined outcome.
Georgiev discusses epiphenomenalism, the theory that consciousness is a by-product of brain processing having only an illusion of causal influence. He points out the evolutionary argument against this view, to the effect that evolution would not select for something that conveyed no selective advantage. In general, he sees the idea that we have no freedom or moral responsibility as counterintuitive. Such a counterintuitive result is seen as the inevitable consequence of explanations based on deterministic classical physics. Quantum mechanics does, however, provide a non-deterministic alternative, in which consciousness underlies the neural processes of making choices and thus effecting future possibilities.
The author goes on to discuss the vexed question of the possibility of quantum coherence in the brain. Mainstream cosciousness studies has managed to fabricate an orthodoxy, to the effect that quantum coherence cannot occur in organic matter. A paper by the physicist, Max Tegmark, is often quoted in this respect. Tegmark asserted what was already an established position, to the effect that quantum coherence in the brain would be too short lived to have a functional role in neural processing.
Tegmark’s paper was aimed at refuting Hameroff’s Orch OR theory, which required quantum coherence to be sustained for 25 ms. Thus Tegmark did not show that coherence over shorter timescales could not support consciousness, because he was directing his argument at the longer timescales of Hameroff’s theory. Georgiev here queries whether there is any evidence that consciousness has to arise over a milliseconds timescale. If consciousness could operate over a picosecond or shorter timescale then Tegmark’s calculations do not present any problem for quantum consciousness. It is pointed out that all neuroscience has been able to show to date is that consciousness does not operate on a scale slower than milliseconds.
Tests show that there is a minimum timescale of about 30 ms needed for a subject to distinguish two sensory inputs as being separate. This means that consciousness cannot be slower than 30 ms. However, patients with time agnosia, who have subjective experience of the passage of time, confirm that it is physically possible to have consecutive conscious steps that are experienced as simultaneous. From this it is argued that the real units of consciousness could be at the picoseconds level, although such units cannot be discerned by the conscious subject.
It is argued here that the upper possible bound of the timescale of consciousness need not be its actual scale. As an analogy, Georgiev takes the example of the operation of a personal computer. The computer screen is on a millisecond timescle with the screen refreshing perhaps every 10 ms. But this is not indicative of the performance of the processor, which may operate on a picoseconds timescale. All that the refresh rate of the monitor can tell us that the processor does not operate on a slower than 10 ms timescale. In the brain, the millisecond timescale applies to the brain’s communications with sensory organs and muscles, but this may not say much about its internal processing.
The author goes on to argue that if consciousness arises at the quantum level some of the conventional arguments of mainstream consciousness theory fail. He contrasts classical and quantum information. Classical information can be copied and stored. A DVD encoded on a string of 0’s and 1’s, which can be read by an external observer, is an example of classical information. With the qbits of quantum information, it is impossible to read them because any interaction with them would alter them. All that can be done is to swap or move the information without deleting it. This inability for third parties to observe quantum information is similar to our inability to observe first person consciousness, while in contrast such inability is alien to classical information systems.
The author argues that it is impossible to copy minds that are based on quantum states because of the no-cloning theorem, which demonstrates that attempts to copy quanta result in the quanta being corrupted. In mainstream consciousness studies, philosophers and others have sought to create wonderment by arguing that it is possible to copy minds, and this appears to be true in principle, if consciousness is based on classical physics. However, if conscious arises from quantum states this becomes impossible. The possibility of copying a mind has also been used as a somewhat convoluted argument against the existence of the self, because in this argument copying the mind would create the paradox of two identical selves. However if copying of minds is impossible this paradox will not arise.