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Quantum Physics

I don't know if you are fascinated by advanced theories of Physics like general relativity, special relativity, or string theory, but I certainly am.

A recent article helped to clarify my understanding of quantum physics, and it's such a refreshing view of the classical theory, that I thought I'd share it with you, my friends, who I can only surmise are chomping at the bit to bring up the finer points of quantum theory in general company at a cocktail party, for instance.

To wit, take a gander at this article. The part I found to be particularly insightful (in as much as it bestowed upon me some insight), was the passage:

To the question, "Why does the world appear to be quantised?" Zeilinger replies, "Because information about the world is quantised."

After all, a fisherman who uses a coarse net to fish the oceans for fish may pronounce that "there are no living creatures in the sea smaller than this here herring, the smallest fish I have ever caught." Meanwhile, a fisherman who uses a finer net, might suggest that, in fact, the ocean also contains minnows. This imples that the tools we use to probe the universe may, by their very nature, be incapable of gathering data that accurately describes the actual dynamics of the universe they are measuring.

Therefore, quantum theory will only be able to describe the universe to the detail of quantization defined by the granuarity of the observations our tools can make, rather than the granularity of the universe itself. Consider, for example the definition of Planck Length and Planck Time.

This in turn reminds me of another physicist, Sir Isaac Newton, and his (not so?) famous quote:

"I do not know what I may appear to the world, but to myself I seem to have been only like a boy playing on the sea-shore, and diverting myself in now and then finding a smoother pebble or a prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me."

Newton, one of the most learned men of his time (much ahead of his time, in fact), is lamenting being only vaguely familiar of the "undiscovered truth" lying in plain view.

At first, this seems to be in conflict with what Descartes has to say in Discourse on Method:

"...everything which could be known by human beings could be deduced one from the other in the same way, and that, provided only that one refrained from accepting anything as true which was not, and always preserving the order by which one deduced one from another, there could not be any truth so abstruse that one could not finally attain it, nor so hidden that it could not be discovered."

However, if you put a particular emphasis on "which could be known by human beings", his philosophy remains unchallenged by the principle that the universe may be comprised of forces that are too continuous for the discrete instruments we are using measure it.

But what I find most interesting is that we may actually have a rough idea of just how many pebbles our thirst for science and knowledge have turned up, and just how broad and expansive the undiscovered ocean before us truly is. If you followed the link about Planck time (or already knew what it was), the following article gives an indication just how coarse our net is; just how many fish in the sea our nets may actually be missing.

Specifically, the shortest time ever measured is 1^-18 seconds, or roughly twenty-six orders of magnitude greater than the theoretical limit of discretely observable times. To get a sense of just how gross a measurement this is, if you caught a fish 20cm long in a fishing contest, and exagerrated the size of it by twenty-six orders of magnitude, it would be 2,114,046,820 light years in length. By comparison, this distance is about three times greater than the most distant object ever measured, meaning that if we pointed Hubble in the opposite direction of Abell 2218 and found an object equally distant, the size of your exaggerated fish would be larger than the greatest observed size of the universe.

This gives you a rough idea of just how coarse an understanding of the natural world we are able to know, a rough idea of just how large the undiscovered ocean of truth before us, actually might be.

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