Hypotheses of consciousness and spacetime

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Space-time theories of consciousness relate the geometrical features of conscious experience, such as viewing things in space-time at a point, to the geometrical properties of the universe itself.

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[edit] Background

Space-time theories of consciousness have been advanced by Arthur Eddington, John Smythies among others. The concept was also mentioned by Hermann Weyl who wrote that reality is a "...four-dimensional continuum which is neither 'time' nor 'space'. Only the consciousness that passes on in one portion of this world experiences the detached piece which comes to meet it and passes behind it, as history, that is, as a process that is going forward in time and takes place in space".

In 1953, C. D. Broad, in common with most authors in this field, proposed that there are two types of time, imaginary time measured in imaginary units (i) and real time measured on the real plane.

Different types of time are introduced in these hypotheses because they can interact mathematically in the equation of spacetime to produce no separation between two points. The equation of spacetime gives the spacetime separation (Δs) between two points as:

Δs2 = Δx2 + Δy2 + Δz2 − c2Δt2

In recent years this has been interpreted as a dynamical equation but when it was first formulated it was interpreted as a geometrical equation, specifying actual separations. The geometrical interpretation arose because it was proposed that the minus sign was the result of multiplying ciΔt by ciΔt where i is the square root of minus one (See Einstein (1920)). It can be seen that for any separation in 3D space there is a time at which the separation in 4D spacetime is zero. Similarly, if another coordinate axis is introduced called 'real time' that changes with imaginary time then historical events can also be no distance from a point. The combination of these result in the possibility of brain activity being at a point as well as being distributed in 3D space and time. This might allow the conscious individual to observe things, including whole movements, as if viewing them from a point.

It should be stressed that, although not impossible, the simple geometrical interpretation of spacetime using imaginary numbers is no longer widely accepted in physics. It is however often used to simplify calculations and is implicit in the Wick rotation.

John Smythies proposes that there are extra dimensions for arranging things that form a separate "phenomenal space of consciousness". The phenomenal space would be a physical instantiation of Descartes' Res Cogitans, the point from which he proposed things in the brain were seen.

Alex Green has developed an empirical theory of phenomenal consciousness that proposes that conscious experience can be described as a five-dimensional manifold. As in Broad's hypothesis, space-time can contain vectors of zero length between two points in space and time because of an imaginary time coordinate. A 3D volume of brain activity over a short period of time would have the time extended geometric form of a conscious observation in 5D. Green considers imaginary time to be incompatible with the modern physical description of the world, and proposes that the imaginary time coordinate is a property of the observer and unobserved things (things governed by quantum mechanics), whereas the real time of general relativity is a property of observed things.

In 2001, Elizabeth Rauscher developed a detailed theory of an eight-dimensional complex Minkowski space in which such phenomena as remote viewing would be possible as well as apparently being able to view things at a point.

These space-time theories of consciousness are highly speculative but have features that their proponents consider attractive: every individual would be unique because they are a space-time path rather than an instantaneous object (i.e., the theories are non-fungible), and also because consciousness is a material thing so direct supervenience would apply. The possibility that conscious experience occupies a short period of time (the specious present) would mean that it can include movements and short words; these would not seem to be possible in a presentist interpretation of experience.

Theories of this type are also suggested by physical cosmology. The Wheeler-deWitt equation describes the quantum wave function of the universe (or more correctly, the multiverse). This equation does not involve time. Time was explained by Bryce De Witt by dividing the multiverse into an observer with measuring devices and the rest of the universe. The rest of the universe then changes relative to the observer. This introduction of time results in the occurrence of space-time, gravity and the rest of the observed material world. As the famous cosmologist Andrei Linde puts it:

“ The general theory of relativity brought with it a decisive change in this point of view [the 3D world]. Space-time and matter were found to be interdependent, and there was no longer any question which one of the two is more fundamental. Space-time was also found to have its own inherent degrees of freedom, associated with perturbations of the metric-gravitational waves.

...
Is it possible that consciousness, like space-time, has its own intrinsic degrees of freedom, and that neglecting these will lead to a description of the universe that is fundamentally incomplete?

 ”

—Andrei Linde

[edit] Predictions

Proponents of the "Space-time theories of consciousness" assert that they make predictions, and are thus to be distinguished from pseudoscience. These predictions are not known to have been tested specifically.

The empirical theory of Alex Green predicts that a small part of the brain such as the centromedian nucleus will be sensitive to mechanical deformation and topical application of general anaesthetics, that cognitive experiments will demonstrate the creation of models of the world by the cerebral cortex that form the input to conscious experience and that consciousness is involved in the maintenance of the global stability of brain activity.

The theory of Elizabeth Rauscher predicts that certain psychic phenomena, in particular remote viewing will occur. This prediction has been examined but the existence of remote viewing is not accepted by mainstream scientists.

[edit] See also

Wikibooks
Wikibooks' Consciousness studies has more about this subject:

[edit] References

[edit] External links


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