A technician explains measurements whilst a scientist explains observations.

Simultaneity - the key to understanding mind?


When Christ taught in the temple
The people all stood amazed
Was teaching the lawyers and the doctors
How to raise a man from the grave
Blind Willie Johnson


Do we see and generally experience things simultaneously? If we do then having more than one distinct thing in our experience at a time means that our experience is a "space". Indeed, more than one thing being present at an instant is a definition of the term "space".

On reflection it would be difficult to imagine how our experience could occur if it were not events in a space. Suppose your experience was a single quantum flowing in a wire, would that be like an experience that contains this text? Suppose it was billions of quanta flowing sequentially in a wire, at each instant it would still be but one quantum in a wire at a given point. If we are to experience slabs of colour or sounds and sights occurring together then we must have a space that is our experience.

It seems that our minds, which are simply our experience, are events in a space. If this is so then it is most likely that the events in our minds are some sort of copy of the events in the world around us (See Why direct and naive realism are unscientific ). This copy is probably held in our brains.

The main problem with this reasoning is that, as yet, there is no single set of events distributed in space in our brains that appears to correlate exactly with experience. This is not an insurmountable problem however, because the most likely place for such a space is the thalamus and small scale events in the thalamus have not been explored in any depth as yet. Certainly removal of the thalamus removes the mind but it also removes most of the connections from the cerebral cortex to the periphery and vice versa. Whether the thalamus is simply a junction or the location of the mind is still an open question. It is also evident that our experience is arranged in at least four dimensions (see An Introduction to New Empiricism) so the instantaneous, 3D measurements of brain activity do not represent the final form that this activity adopts in our minds and hence the failure to find an exact correspondence between measurements and experience would not be unexpected.

There have been a few attempts to undermine the idea of simultaneity in our experience. Dennett and Kinsbourne (1992) developed a "Multiple Drafts" theory of perception in which the brain was supposed to simply produce verbal reports in response to what was happening in the world and has no representations of the world modelled inside it. In this theory we do not experience anything in our brains, we only experience the world at large. However, work by Larsen et al (2006) and Blankenburg et al (2006) tested the predictions of the Multiple Drafts theory and showed that the brain really does model events in the world and we experience these models. It is also the case that the Multiple Drafts Theory assumes the appearance of lights as slabs of colour and hence contains the contradiction of both assuming simultaneous events in a mental space and denying that these occur.

What sort of physics might explain mental space? Several theorists have had a stab at this problem (See for instance Green (2002) and Rauscher & Targ (2001). The basic idea is that the universe may have five or more dimensions (3 space, time and at least one more time like dimension) and that the space of the mind is due to projective geometry. The projective geometry would create a geometrical focus where all the events in the mind appear to be directed. I do not think that these theorists are definitely right but I do believe they are looking in the right direction!

Relativity, simultaneity, measurement and observation

Measurement is a transfer of state from one place to another whereas observation places events such as measurements in the space and time of an observer. In an observation events occur relative to an observation point and are simultaneously present. Observation gives measurements immediate meaning and is at the heart of science (see New empiricism and meaning). The scientific method works because it uses an experimental approach that, in principle, allows any person to check an empirical theory through direct observation.

Measurement can be used to create a model of a system under observation, a sort of copy of the world, for instance, as a simulation in a computer, but measurement does not perform observations. Zurek and others have tried to redefine observation as simulation and have developed "decoherence theory" on this basis. However, there still remains a "preferred basis problem". As Wallace 2007 says: "Sometimes it is easy to forget how grave a problem the ‘measurement problem’ actually is". It is also becoming evident that there are serious problems with the treatment of time in modern quantum theory (See Horwitz 2006) that undermine Zurek's reasoning.

In general any observer has their own manifold of events around them (a manifold is a set of events that are arranged in independent directions like up-down, left-right etc, the number of independent axes used in the arrangement is the number of dimensions in the manifold). In Newtonian physics these manifolds are related by the separations of the observers. In Relativistic Physics the manifolds are also separated by phase, the progressive temporal discrepancy that occurs along the direction of any relative motion. The existence of phase means that each particle in the world has its own peculiar observational manifold because even tiny motions can create attosecond phase differences, as Stein put it: "in Einstein Minkowski spacetime an event's present is constituted by itself alone". So, according to Relativity the only true observer is a space-time point. However, a point in three dimensional space cannot contain any information because information requires representation in a physical substrate. What about a four dimensional point? If Minkowski's light cone equation is regarded as a truly geometrical relationship so that:

0 = x2 + y2 + z2 - (ct)2

is the equation of an observation point where the shell of events with spatial positions (x2 + y2 + z2) are bridged together at a point then the problem of observation might be solved because information can be instantiated as events in space and time but also at a point. (See Time and conscious experience).

Can a Turing Machine be a “scientist”?

The difference between measurement and observation becomes clearer if the mechanics of machines that just shift matter from place to place are compared with the abilities of a scientist.

Suppose a Turing Machine had a program that directed it to produce the simplest possible computational description of the universe and controlled robotic machines that could be directed to create the appropriate apparatus and perform experiments. In principle the machine might eventually contain a set of bits that represent the elements of the computation. In fact here is the answer:

%^$&^$^&xx iuytfgdvgjh = 6576fhgf [dkjdgdjdyryte] {uytuyb} %jhg %$$&^)(_

Well, one day, when the machine has done its work we will be able to find the transformation equation from my bits to the bits in the machine.

Of course, the machine’s constructors will be able to say that it is not the final equation that is the substance of the Turing Machine’s achievement, it is the models that it makes. They will be able to demonstrate flying machines and food creators, molecular manipulators and planetary classifiers… These models, or four dimensional descriptions of nature, will be very impressive but then I will ask “how do they work?” and the operators will have to admit that I had a possible answer in May 2011. Not only did I have a possible answer but had the machine used the correct encoding from the outset it would scarcely have needed a transformation equation to produce my original answer. Yes, the objective, computational machine knows everything but understands nothing, its final equation is gibberish on its own.

Fortunately, as I watch the Turing Machine construct its models I will be able to remember how they were made. In a quiet moment, as I load these memories into my conscious mind I will be able to imagine how the equation relates to the flight of a plane with the meaning of y = 3x^2 as an actual motion of the vehicle in the multidimensional geometrical manifold that is my mind which contains both motion and position now. Understanding includes time extended events now, it is the placing of measured (objective) variables into a manifold that has an existent time coordinate. The “objective” is measurement, the subjective is “observation”.



References

Blankenburg, F., Ruff, C.C., Deichmann, R., Rees, G. and Driver, J. (2006) The cutaneous rabbit illusion affects human primary sensory cortex somatotopically, PLoS Biol 2006;4(3):e69.
Dennett, D. and Kinsbourne, M. (1992) Time and the Observer: the Where and When of Consciousness in the Brain. (1992) Behavioral and Brain Sciences, 15, 183-247, 1992. Reprinted in The Philosopher's Annual, Grim, Mar and Williams, eds., vol. XV-1992, 1994, pp. 23-68; Noel Sheehy and Tony Chapman, eds., Cognitive Science, Vol. I, Elgar, 1995, pp.210-274.http://ase.tufts.edu/cogstud/papers/time&obs.htm
Green, A (2003). The Science and Philosophy of Consciousness. http://www.users.globalnet.co.uk/~lka/conz.htm
Green, Alex (2002). The Description and Definition of Consciousness. Science and Consciousness Review
Larsen, A., Madsen, K.H., Lund, T.E., and Bundesen, C. (2006). Images of Illusory Motion in Primary Visual Cortex. Journal of Cognitive Neuroscience. 2006;18:1174-1180.
Rauscher, E.A. & Targ, R. (2001) "Speed of Thought: Investigation of a Complex Space-Time Metric to Describe Psychic Phenomena." Journal of Scientific Exploration, Vol. 15, No. 3, pp. 331;354, 2001

Wallace, D. (2007) The Quantum Measurement Problem: State of Play. arXiv:0712.0149v1 [quant-ph] 3 Dec 2007 http://arxiv.org/abs/0712.0149

Horwitz, L,P. (2006) On the significance of a recent experiment demonstrating quantum interference in time. http://www.citebase.org/abstract?id=oai:arXiv.org:quant-ph/0507044






3 comments:

  1. "On reflection it would be difficult to imagine how our experience could occur if it were not events in a space. "
    I have a different way of approaching it. Imagine that you feel hot and sad at the same time, while smelling the aroma of pancakes and thinking about a word that rhymes with Kleenex. This does not require a presentation of literal space but rather a capacity for figurative distinction despite literal simultaneity. Multi-channel sensorimotive protocols which are unlike object-space topologies in every way.

    Where objects are discrete and public, sensation is continuous and private. This is not a coincidence, but rather an ontological symmetry. Using this symmetry as our foundation, we can propose that the world which we experience progresses in an additive way (the arrow of time, accumulation of evidence or data through observation, etc), may be an inversion of the native subjective process which we can infer to be (at least somewhat) subtractive: It pulls 'wholes' through holes.

    This theme can be seen in many aspects of perception, such as how we are able to see 'through' a screen of LCD pixels to the image it contains for us. So too, in idioms such as

    Connecting the dots
    Solving a problem
    Filling in the blanks
    Bridging the gap
    Figuring it out
    Putting two and two together
    Getting from A to B

    There is a sense that intelligence involves a power to perceive an underlying unity of apparently separated elements. The idioms use space figuratively, but I think that should not be used to support the assumption of literal space but rather as an indication that the experiential referent, the 'aha' feeling of putting two and two together, is one of personal significance and sequential narrative which uses space as a prop.

    True space, I think, can only arise from unconscious settling of objects which are not free to change their position. Our idea of space is rooted in the consistency of inanimate objects that comprise our external world. We put something down on a table and we can expect it to still be there a week later. There is no parallel consistency in the psyche. Even with the possibility of Superior Autobiographical Memory (which does seem to present memory of events in more of a visual-spatial topology) we are aware that whatever spatial modeling that the psyche can conjure up is not a literal space which can be used, for example, to store literal objects.

    I think that it is useful to explore all of the options for universal fundamentals - to say that the psyche must be space will yield one set of truths, just as Einstein's understanding that space must be time has yielded a new set of truths. I think that the greater truth is that the fact that each of these fundamental propositions makes sense in its own way reveals the deeper role of symmetry itself. Personally, I think that breaking the cosmos down to two sets of three: (matter-energy-space) and (sense-motive-time)is the most important and under-explored dichotomy. In this configuration, space and time are merely the abstract where and when property which arises from the necessity for sense and motive to interact with its objectified self (matter and energy).

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  2. You say: "whatever spatial modeling that the psyche can conjure up is not a literal space which can be used, for example, to store literal objects."

    I think that we differ about the meaning of the word "space". You seem to be using "space" to mean a three dimensional manifold such as 3D Euclidean space. The relations between the dimensions in this space are described by Pythagoras' Theorem:

    h^2 = x^2 + y^2 + z^2

    This was the first "space" discovered by mathematicians. There are a vast number of other possible spaces. The most interesting being "spacetime" which is the type of space that best approximates our world:

    s^2 = x^2 + y^2 + z^2 - (ct)^2

    Our role as scientists is to observe and then model what we observe with an hypothesis. Certainly a 4D spacetime is similar to our experience, all points are at no separation from a geometrical observation point but not within it and events are successions of simultaneous points.

    If we look at your list: Connecting the dots, Solving a problem etc. these processes result in an output in a projective mental space that is at least a 4D manifold of points (like the real world). Our brains operate like a Turing machine linked to an n dimensional spacetime manifold.

    I can only really speculate on what occurs in my experience (empirically). Events occur within my experience such that they are extended in time so I can say that there is a temporal axis for arranging them and at each point in the temporal axis there are many events so I can say there is space. Whether this spacetime of experience is the same as the spacetime of the world in general can only be ascertained by experiment. My guess is that there is no reason to suppose that they are not the same.

    You talk of "Multi-channel sensorimotive protocols which are unlike object-space topologies in every way". If I experience the qualia you describe I find that "hot" is located in my body or skin, aroma is displaced onto a foodstuff, the rhyming is inner speech between my ears - all these qualia are located in a space. Please give me an example of multiple channels that are not spatially arranged. There is no need to invent a totally new physics to describe simultaneous events in our experience because they have locations in a projective geometry and are accommodated easily in spacetime.

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  3. ps: thank you for raising these discussion points!

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