Physics and freedom.

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Benjamin franklin

Contents:


Special relativity principle.

Since news-papers started their Green columns, ecology has rivalled astrology, as a concern with intimate influences on our lives, from near or far.
The natural philosopher used to think of himself as apart from nature. He has prided himself in being a detached observer of the world around him. He didnt see why the way he looked at things should change what he saw.

He searched for the laws that governed the motions of the stars and other projectiles, to make them predictable. Laws are statements of precise conditions under which a general law operates.
Chaos theory was to show how the tiniest change in the conditions produced a different result, that was unrepeatable and unpredictable. The classical science of the pendulum swing is repeatable enough. But under certain forced oscillations, non-repeatable swing patterns emerge, in these and allied phenomena, as strange and beautiful as the intricate contours of butterfly wings.

But, long before chaos theory, classical physicists were obliged to accept a new rule that took into account the different times and positions, in which their observations were taken, if they were to agree that the motions of bodies, they observed, followed laws of physics.

This new rule was the special theory of relativity. It postulated that nothing can move faster than light. Trying, to over-take a light ray, slows the clock down; the space-measure or ruler shortens, and one becomes more massive, in one's frame of reference, relative to another observer's.

Equations were devised ( the Lorentz transformations ) to relate their different space and time co-ordinates, as demonstrably the same observation. Actually, their different measurements could be shown to be the same measurement, from the point of view of a four-dimensional 'space-time'. That is a generalisation of Euclid's classical geometry in three dimensions with time as a fourth, space-like dimension.
This common measurement in space-time, that all possible observers have of the same event, is called Minkowski's 'Interval'.

Hence, the ( abused ) conclusion that relativity is reality. Misunderstandings, also, have beset the Uncertainty principle, that other most renowned principle of twentieth century physics.


The Uncertainty principle.

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Relativity showed that observers must make explicit their conditions of observation, for their respective observations to agree. But the Uncertainty principle showed how observers must also take into account the influence of their observations on what they observe.

A physicist can more or less accurately measure the position or momentum of a sub-atomic particle, but not both together. Focusing a very short wavelength of light ( an electro-magnetic wave ) on such as an electron, its position will show-up precisely. But the high energy of short waves will boost the particle's momentum.
A low-energy long wavelength ( like a gentle swell ) must be used to measure the particle's momentum. But the longer the wavelength, the less clearly defined the particle's position.

The more certain you make of position, the less certain the momentum, and vice versa. The measure is one of probabilities. And to choose to measure the one is also to choose to change the other. In effect, science and ethics are as inter-dependent as space and time.

In an interview with J W N Sullivan, in The Observer 13 april 1930 ( quoted in C E M Joad's Guide To Modern Thought ) Erwin Schrodinger commented:

the fact that we cannot predict the behavior of individual atoms 'is not a mere practical disability; it is due to the actual nature of things. Thus something like free will is placed at the basis of natural phenomena.'

This may not have been Shrodinger's view always, but the fact he entertained it, at this early date, is perhaps significant.

The uncertainty principle is a refutation of purely passive observation or 'pure science'. A minority of physicists refused to accept that, in principle, the observer must affect the observed, tho this was first noticable only on the very small scales of experiments in quantum mechanics.

The rebel physicists, including Einstein, argued that the theory of quantum mechanics, derived from the uncertainty principle, was incomplete. In the nineteen thirties, the Einstein-Podolsky-Rosen experiment was actually a 'thought experiment' or imagined situation, in which they believed the quantum theory would be disproved. By about 1980, Alain Aspect's experimental technique began to show for one side of the argument.

Take a system of two particles, whose attributes cancel each other out. One is in an equal and opposite state to the other, such as spin-up versus spin-down, or spin-right versus spin-left. An experimenter may turn a magnetic field to a particle, to change its spin from up to right. To be conserved as a system, the other particle, no matter how far separated, will change with it, from spin-down to spin-left.

But those devils advocates, the creative critics of quantum theory objected that this would not happen, because it would be a violation of the principle of local causes.
The champions of quantum theory said the latter would have to go, instead. That raised the question of how one of the two particles could re-orient itself to the other, when they had not even the time to exchange light signals?

The idea of a quantum is that of a 'packet' of energy. Sub-atomic particles dont gain or lose energy gradually but in a 'quantum jump' between energy levels. If this quantum jump was limited to the speed of light or less, the transition between states would not be a jump, but continuous change of energy.
So, super-luminal connections between the two-particle system seems logical. And experiments, by the 1970s and 1980s were beginning to confirm these faster-than-light connections.

However, other explanations were sought and the assumptions underlying these tests were examined. The experimenter throws a switch, to affect one of the particles one way, and thereby its distant partner in the opposite way. But was that experimenter really free to switch the way he did?

These issues were discussed in the last chapter of Gary Zukav's The Dancing Wu Li Masters. Free-will is given an operational meaning that should be testable, in terms of free variables, being the choices of two observers or experimenters, in different locations, between the two possible states of the two-particle system.

Alternatives were considered: that there is no freedom in the universe, but that it is one super-determined whole, that never could be any different to what it was. Or: every possible option, facing us, has a reality of its own. For instance, the experimenter may have turned the switch up in this reality, but in another reality he turned it down.

Thus, reality would no longer mean our unique existence in the universe but many existences in a 'multiverse'. Hence, the many-worlds theory, indulged by science fiction writers. ( Indeed, every guess is a science fiction until shown a fact. )

A multiverse, in which every possibility happens, suggests infinite choice. Conversely, a universe, in which only one possibility happened, could not disprove we have zero choice. These two extreme scenarios suggest a whole range or spectrum of choice, from zero to infinite choice.
Also, having choice, to some extent, might define the existence, to that extent, of a multiverse?

Physicists may generalise the conception of the physical universe into a multiverse, as argued by David Deutsch, in The Fabric of Reality.


Conclusion: a general theory of choice.

However, it should also be possible for physicists to make explicit and generalise the logic of choice, which conditions their observations and, therefore, what they know. We have seen this process in relativity theory, which allowed observers to choose wider conditions of observational agreement, under generalised laws. Further, the uncertainty principle showed choice of observation itself an actual condition of what we could know.

The most general theory of physics should depend on the most general theory of choice. To be truly general it must be a theory not only of physics but all human activity, including, of course, elections, political or otherwise.

It is a fact that there is a successful general theory of elections, that has been evolving since the middle of the nineteenth century ( as explained on my web pages Scientific method of elections and elsewhere ).


Richard Lung.



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