We have mandatory reading in every class each semester (according to the principal) and my physics teacher thought that "The Dancing Wu Li Masters" would be an interesting book for most of us. It's pretty good, albeit a little bit elementary, but it had an interesting excerpt here.

This chapter was kind of talking about Quantum Physics. I don't want to quote so much that it's too long to read but you'll need context to know what it's talking about ..

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The ability to predict the future based on a kowledge of the present and the laws of motion gave our ancestors a power they had never known. However, these concepts carry within them a very dispiriting logic. If the laws of nature determing the future of an event, then, given enough information, we could have predicted our present at some time in the past. That time in the past also could have been predicted at a time still earlier. In short, if we are to accept the mechanistic determination of Newtonian physics--if the universe really is a great machine--then from the moment that the universe was created and set into motion, everything that was to happen in it already was determined.
According to this philosophy, we may seem to have a will of our own and the ability to alter the course of events in our lives, but we do not. everything, from the beginning of time, has been predetermined, including our illusion of having a free will. The universe is a prerecorded tape playing itself out in the only way that it can. The Great Machine runs blindly on, and all things in it are but cogs.
According to quantum mechanics, however, it is not possible, even in principle , to know enough about the present to make a complete prediction about the future. Even if we have the time and the determination, it is not possible. Even if we have the best possible measuring devices, it is not possible. It is not a matter of the size of the task or the inefficiency of detectors. The very nature of things is such that we must choose which aspect of them we wish to know best, for we can know only one of them with precision.
As Neils Bohr, another founder of quantum mechanics, put it:
. . . in quantum mechanics we are not dealing with an arbitrary renunciation of a more detailed analysis of atomic phenomena, but with a recognition that such an analysis is in principle excluded.

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Originally posted by ThePanacea
Also, I had a question about the uncertainty principle (we can't know both an objects position and velocity. The more accurately we know one the less accurately we know the other. If we know its exact velocity we do not know its exact position, etc). What is "position" relative to? The center of the universe (when dealing with galaxies?), the center of an atom, the distance from us, or what?

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Wow I feel stupid right now. I thought I read something where Hawking applied it to say we don't know our galaxy's true velocity, but now that I think of it I must have been way off. heh

Also, it seems that the uncertainty principle deals with the poor instruments that we are forced to use (gamma rays/light waves, etc). If we eventually found something that managed to measure velocity without changing a particle's position, would the uncertainty principle not become obsolete?

Also, something common that GhostNuke and Jigga_Man like to quote (wrongly I believe) is me saying "Nuclear bombs of today are not the same as atom bombs of yesterday". I think I said something to that effect, though my wording might actually have been better. Well, as I thought at the time until it seemed clear to everyone that I was wrong, after reading it in this book I'm reading, a hydrogen bomb uses fusion and is many, many times more powerful whereas an atom bomb uses fission and is not nearly as powerful. Thus, nuclear bombs of today (hydrogen bombs) are indeed not the same as atom bombs of yesterday."

Originally this actually came from my teacher when we were having a discussion in class. He seemed like a bright guy and I took his word for it (it was something somewhat unrelated) and I made that post. When I was wrong I just assumed I'd try not to make myself look stupid and say that I meant that nuclear bombs of today are just much more powerful, but I think I was actually correct. I may be wrong about what I said, as it was awhile ago, but if anyone would care to find the thread and prove me wrong feel free to go ahead. I think we were talking about India/Pakistan or North Korea or something.

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Also, I had a question about the uncertainty principle (we can't know both an objects position and velocity. The more accurately we know one the less accurately we know the other. If we know its exact velocity we do not know its exact position, etc). What is "position" relative to? The center of the universe (when dealing with galaxies?), the center of an atom, the distance from us, or what?

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And like flipping a coin a gazillion times, you'd expect 50.00000% of the flips to be heads. So, the left/rights basically cancel out... any small deviancy (a left/right push) is insignificant to the size of the baseball. The randomnesses cancel out in a big system.

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Also, it seems that the uncertainty principle deals with the poor instruments that we are forced to use (gamma rays/light waves, etc). If we eventually found something that managed to measure velocity without changing a particle's position, would the uncertainty principle not become obsolete?

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That's kind of misleading. The expectation value is 50%, but the deviation moves as the square root of the number of tosses.

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