Mind, Brain & the Quantum
Lockwood claims that there is nothing in physics or chemistry as currently understood to account for the inner or subjective life that we experience. Considerable progress has been made in understanding how the brain processes information, but this has thrown little light on why these processes are associated with subjective experience. Moreover, Lockwood feels that simply accumulating more knowledge of the type that neuroscience produces is unlikely to solve the problem.
Relativity & Frames of Reference
The recurring theme of this book is the apparent conflict between special relativity and our subjective experience of time as something that flows from the past into the future. The concept of relativity began with Galileo. He used the thought experiment of a ship moving at a constant pace on a calm sea. Water dripping from a bottle falls vertically downwards onto the floor of the ship’s cabin, it does not fall towards the stern of the ship, which it would if it were to fall vertically towards the spot on the planet that the water was directly above when it started to fall. In modern conditions it is easy for anyone to witness this experiment. If someone drops something in a plane or a train, it falls directly to the floor, and does not hurtle towards the back of the means of transport. This was an extremely important insight. It demonstrated that there was no absolute spatial frame of reference in the universe, and that each observer or indeed object had an individual frame of spatial reference.
One of Einstein’s insights in special relativity was to extend the concept of individual frames of reference to include time, as well as the three spatial dimensions, and thus to create the new concept of spacetime. Time was conceived of as being like space in that it was just there extending in all directions. This led, however, to a conceptual problem. Space had never been conceived of as flowing, but time was subjectively perceived to flow from the past and into the future. But this became an unscientific view once time was perceived as extending everywhere, and being the same sort of thing as space.
Light Cones & the Absolute Elsewhere
Further to this, the concept of the light cone is crucial to special relativity. Those things which effect an observer lie within the observer’s past light cone, that is the rays of light reaching the observer from the past. Events for which there has not been enough time for rays of light to reach A lie outside the past light cone, and therefore can have no physical influence on A. Similarly events which can be influenced by A lie within its future light cone, being those parts of the universe, which there has been sufficient time for light from A to reach. Other areas lie outside the future light cone, and cannot have yet been effected by anything which has happened at A. Areas which lie outside both the past and future light cones can neither effect A, nor have yet been effected by A. These areas are referred to as the ‘absolute elsewhere’ and for all practical purposes can be viewed as being outside A’s universe.
Lockwood discusses the situation in special relativity where an event can be in the future of observer A but in the past of observer B, despite the fact that observer B is actually situated in the past of observer A. He explains with the help of a diagram how this is possible. In a two dimensional diagram, i.e on the page of a popular science book, A which is a stationary observer has a horizontal line or simultaniety plane passing through it, indicating the present or ‘now’ for its frame of reference. Anything lower down the page is in the past, and anything higher up the page is in the future. If we take a point C, which might be an event in another galaxy, that is further up the page than the simultaneity plane of A, it is deemed to lie in the future of A.
However, the observer B, that lies in the past of A is moving and because of this its simultaneity plane is not horizontal, but runs at an upward angle across the page, such that it eventually crosses that of A, and comes so far up the page that it is higher up than the point C. Therefore C is deemed to lie in the past of B, but the future of A, despite the fact that A is in the future of B.
This paradoxical situation is often taken to verify an entirely deterministic view of the universe, which in particular excludes any possibility of human free will. It seems that the fact that C lies in the past of B but the future of A means that the future of C is predestined. However, it is questionable whether the relationship of the two observers with the event C has any meaning within physics. The paradox described here can only arise when C lies outside the light cones of A and B in the absolute elsewhere, that is when it is impossible for C to influence A or B or visa versa. It is arguable to what extent the point C means anything for A and B.
David Bohm in his book on special relativity uses the example of a star visible from Earth. Because the star is many light years away, and is visible to the observer, it lies in the past light cone of the observer. With some knowledge of astronomy it might be possible to infer the position of the star on the simultaniety plane or the ‘now’ of the observer, but that is only an inference, and the star might have gone into super nova since its light set out towards the observer on Earth. The ‘now’ of the star is in the ‘absolute elsewhere’ a region with no possible contact with the observer. In effect, past and future events and their ordering in the absolute elsewhere are no more than a speculation. In the future of A, C may in fact come to lie in its past light cone, but then there will be no disagreement as to the ordering of events within the then existing past light cone. Within the past or future light cone, events will always happen in the same order, and there will be no violation of causality.
However, even if we accept this view, it does not rule out the plausibility of a deterministic universe. Events in the future light cone of A will evolve according to the laws of physics, and since Newton there has been a strong bias in favour of the deterministic. In Newtonian physics algorithms determine the interaction of particles, and in principle if one knew the position and momentum of all the particles in the universe one could calculate with absolute certainty all future events. This could work just as well within special relativity.
General Relativity & Closed Timelike Curves
However, problems for this view start to arise when we look at general relativity and still more in the difficult relationship with quantum theory. In general relativity space is curved by massive objects and future light cones are tilted in line with the curvature of space. This evolution of gravity/curvature of space becomes one of the deterministic influences in this picture. However, with a sufficiently strong gravitational field, such as within a black hole, the tilt of the light cone could continue right round the massive object until it came back to where it started. This development is described as a ‘closed timelike curve’. As some time would have elapsed, it is coming back into its own past light cone, as one of the influences which should deterministically influence its own future.
This might be dismissed as speculative, and in any case unlikely to impact on the cause and effect of human lives which do not take place in black holes. More direct problems can be seen in integrating quantum theory into this picture. Quantum particles are conceived as evolving as waves representing a superposition of the possible position and other properties of particles. When a choice of position is made for an individual particle the outcome is random. Einstein himself was hostile to the way in which randomness became a factor in quantum theory, as he always favoured a deterministic view of the universe.
It seems that it used to be thought that averaging out over countless numbers of such quantum choices would mean that this randomness would have no significant effect on the large scale world. However, the emergence of chaos theory over recent decades has given this a new slant. Chaos theory is deterministic, but it shows that tiny changes in the initial conditions could result in dramatic differences subsequent conditions, and random choices by a quantum particle might constitute part of the initial conditions.
An unhappy story illustrates this possibility. This concerns a nuclear scientist whose boy friend wearied of her not being able to turn up for dates because of working late. He issues an ultimatum that if it occurs on his birthday, he will dump her. That night she is held up by an experiment involving the random decay of a nuclear particle, which takes an unusually long time to happen. He dumps her, and the two former lovers subsequently marry other people, by whom they each have one child. These children grow up to be the dictators of rival nuclear powers.
Entropy & the arrow of time
Surprisingly, Lockwood fails to discuss the problems of increasing entropy and the non-reversibility of time in relation to relativity. Space and time are viewed as the same thing in relativity, but in both classical physics and everyday life there is one important difference. If we travel for an hour we move spatially. That journey is in principle reversible, allowing us to return to our starting point in space, but we cannot go back through the hour that we traversed on the outward journey, and return to our starting point in time. Time has a scientifically undeniable arrow which is not present in space.
Time’s arrow is most often related to increasing entropy. In a closed system, and the universe is viewed as a closed system, entropy either stays the same or increases, but never decreases. The increase in entropy is loosely defined as the increase in disorder. More accurately, one state has higher entropy than another, if more possible configurations of atoms could represent that state. The high entropy state is thus more likely to arise by chance. An analogy is the throw of two dice. There is three times the chance of getting a score of 7, than a score of 2, and the score of 7 therefore is analogous to higher entropy. Entropy is known to have been very low in the early universe, is higher now, and is predicted to be higher in the future, and this is most often seen as creating the arrow of time.
Lockwood appears slightly glib in passing over all of these problems, and seemingly accepting the deterministic or ‘block universe’ view of relativity. However, his line of argument lies elsewhere. He wonders why, despite the view of past and future, and the ordering of events being a factor of one’s current state of motion, we do in fact have the subjective experience of the flow of time. The throw away view of much of mainstream theory is that the flow of time is an illusion. As so often in consciousness studies, something that does not fit the paradigm is conveniently classed as an illusion. One example used as an analogy to illustrate the possibility of illusion is the sensation of dizziness, which creates the illusion that the environment is spinning round the subject. Lockwood, at any rate is not content to let this pass. He argues that if the flow of time is an illusion, it is not an illusion about the external environment, but instead relates to our stream of consciousness.
Lockwood goes on to discuss mainstream theories of consciousness, such as functionalism and identity theory. In particular, he takes issue with the view put forward by both Wittgenstein and A.J. Ayer that it was impossible to assign a spatial location to a mental event. Lockwood argues that mental events are located in time, and that in relativity space and time are the same thing, and anything that is located in time is also located in space.
Lockwood looks at the instance of a physical event A, which causes a mental event B, which in turn causes another physical event C. Event B will be spatially located within the intersection of the future light cone of A and the past light cone of C, and he considers it would in principle be possible to progressively narrow this down to a tighter and tighter specification of the spatial location.
Lockwood goes on to examine some mainstream consciousness theories. He rejects functionalism, which suggests that any system that can perform the functions of the brain will of its nature produce consciousness. In arguing against this, he points to the phenomenon of blindsight. This is a condition where the patients lacks sight in a part of their visual field. However, when they are asked to guess what is present in the blind area, they have a success rate of much above chance, indicating that the brain is still in fact receiving and processing signals from that part of the field. The most likely explanation appears to be that there is an additional pathway in the brain to the one that has ceased to function, but that the functioning of this additional pathway does not enter consciousness. This suggests that two things can perform the same brain function, but with one being conscious and the other not, which directly contradicts the main idea of functionalism.
Lockwood & Quantum Consciousness
It is only towards the end of his book that Lockwood begins to focus on quantum theories of consciousness. He discusses the possibility that quantum computing could operate in the brain. David Deutsch, one of the originators of the idea of quantum computing, took the view that given the nature of biological tissue, rapid decoherence would prevent brain from supporting any quantum computing. However, Lockwood is less sceptical. He mentions the work of the physicist, Fröhlich, who suggested the pumping of biochemical energy could sustain quantum states of many particles oscillating in phase, known as Bose-condensates, at relatively high temperatures. Such systems could in principle form the basis of quantum computing in the brain. Ian Marshall is attributed with being the first person to suggest that such systems could be the basis of mental states. In particular, Marshall suggested that the holistic state of the Bose condensates might be the basis of the unity of consciousness. Marshall proposed that the amplitudes and phase relations of dipole oscillators could code for phenomenal experience. Anaesthetics, which suspend consciousness, act by binding to specific proteins in cell membranes and possibly elsewhere in the cell. Marshall suggested that this process works by preventing protein molecules from participating in molecular dipole oscillations.
Lockwood repeatedly comes back to the connection between time, consciousness and relativity. In relativistic terms, Lockwood envisages the conscious part of the brain as a spatio-temporal world tube, occupying a certain space in the brain and moving through time. He envisages a phenomenal frame, the contents of which depend on where the frame is positioned. The frame is defined by a preferred set of observables in the brain.
Lockwood goes further in suggesting that time itself is a quantum mechanical observable, with a spectrum of eigenvalues corresponding to a range of possible times, each one capable of manifesting as ‘the time’ or ‘now’, while memory gives access to ‘nows’ that are set in the past. Lockwood does not make much attempt to describe any mechanism by which this would happen in the brain, although his references to Fröhlich and Ian Marshall suggests that he would favour the involvement of Bose-condensates.
Lockwood & the Philosophers
Lockwood is critical of his fellow philosophers in their approach to the stand point that matter is a given and mind is problematic, and for assuming a Newtonian concept of matter that is incorrect. He says that they need to move on from the reassuringly solid matter of Newtonian physics and engage with the more problematic matter of quantum theory. In general, he regrets their failure to tackle the ‘big problems’ such as the mind-body problem. He notes that Wittgenstein regarded mind-body as a pseudo-problem that would be resolved by correct use of language, but points out that philosophy as influenced by Wittgenstein made little progress in resolving this problem.
It is hard not to sympathise with Lockwood’s frustration with modern philosophy. In looking at consciousness, philosophers do not seem to have wished to interpret scientific findings, but rather to back up the interpretations already made by scientists, which are themselves rooted in 19th century physics. There is a sense that philosophy has lost the self confidence to make its own interpretations, and merely sees itself as having a duty to sell the ready-packaged ideas it has received from the scientists. This attitude could be thought to have done much to bring about the current stagnation of consciousness studies, with the mainstream deeply entrenched but if anything further than they were 20 years ago from producing an explanation of consciousness.
Lockwood, Michael – Mind, Brain & the Quantum – Blackwell (1989), ISBN 0-631-18031-1 (pbk)
Bohm, D. – The Special Theory of Relativity – Routledge (1965), ISBN 0-415-14809-X (pbk)
Penrose, R. – The Emperor’s New Mind – Oxford University Press (1989) ISBN 0-19-286198-0
Penrose, R. – The Road to Reality – Jonathan Cape (2004) ISBN 0-224-04447-8