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Quantum Trickery - Einstein's Strangest Theory

breckinshire writes "The New York Times is running an interesting story on Einstein's strangest theory. The theory was brought to light this past fall when 'scientists announced that they had put a half dozen beryllium atoms into a "cat state." [...] These atoms were each spinning clockwise and counterclockwise at the same time.' It is an interesting writeup for even the uninitiated and also concentrates on Einsteins role as a 'founder and critic of quantum theory.'"

5 of 531 comments (clear)

  1. Quantum theory means the world may be a simulation by RedLaggedTeut · · Score: 4, Interesting

    I believe the existance of a working quantum theory means that the universe can be considered as a simulation insofar as there might exist a universe without quantum physics and just particle physics.

    Now assume someone with insufficient knowledge about such a universe who tries to model a simulation to get predictions, much like having for of war in a strategy game - when a unit disappears into fog of war (since x turns ago), it would be essentially in all places that in could reach in x turns at once.

    An interesting question then might be, is then human knowledge and usage of quantum theory a desired property of the simulation, or an artifact that invalidates the simulation results?

    --
    I'm still trying to figure out what people mean by 'social skills' here.
  2. Physicists Don't Seem too Philosophical by putko · · Score: 4, Interesting

    One thing I got from the article is that physicists don't really care that the Quantum mechanics doesn't make sense at the macro level, nor that there isn't a clear boundary between big systems and quantum systems.

    That's the whole point of the cat-in-a-box: if an electron can be superposed, why not a whole cat? And what does that say about reality, if the quantum theory makes no sense? E.g. our sense of reality says the cat is either alive or dead, not both. Hence, shouldn't an electron be one or the other? Q.T. says no.

    That "why" issue is the sort of thing that troubled a philosopher-type like Einstiein --- someone who wonders "why?" compulsively is likely to keep on digging. The physicists seem happy to crunch the numbers, do an experiment and see if it agrees with the numbers.

    Which is in keeping with my observations of physicists: they are essentially applied mathematicians. Mathematicians (like Einstein) are a different sort.

    --
    http://www.thebricktestament.com/the_law/when_to_s tone_your_children/dt21_18a.html
  3. Einstein was right, these guys are still on crack! by minkwe · · Score: 4, Interesting
    The core of this issue is one of epistemiology. Bohr and his followers want to transfer a property of the mind (knowledge) to a property of nature (reality).

    It's like saying, something happens in reality only the very moment you know it. Turn on CNN, and all what they are reporting on, just happened at that very moment you learnt of it, and if you did not hear it or know it, then it did not happen! Crack!

    An electron has a specific velocity, whether any person knows it or not. The probability distribution of the electron's velocity (wavefunction) is not a property of nature as Heisenberg states, but a property of our minds (lack of complete information). When that value is finally measured, we have a single value rather than a wavefunction (complete information). It is our minds that have changed, not reality. Therefore it is crack to say the electron has many velocities (wavefunction) before measurement but as soon as it is measured, it collapses (wavefunction collapse) into a single value.

    The strangest part of this is that this blatant confusion has not totally incapacitated the usefulness of quantum mechanics. Imagine what will happen if more physicists could get their ducks in line and properly understand why Quantum mechanics works. Einstein was on track. Others have followed him and been able to do great things, although clearly disagreeing with the "spooky action at a distance" "copenhagen" interpretation. Such as Schrödinger, Edward Thomson Jaynes, the father of "maximum entropy".

    ET Jaynes wrote about the possibility of doing a thesis under Oppenheimer:

    After some months of correspondence I first met J. R. Oppenheimer in September 1946, when I arrived at Berkeley as a beginning graduate student, to learn quantum theory from him -- the result of Bill Hansen having recommended us strongly to each other. When in the Summer of 1947 Oppy moved to Princeton to take over the Institute for Advanced Study, I was one of four students that he took along. The plan was that we would enroll as graduate students at Princeton University, finish our theses under Oppy although he was not officially a Princeton University faculty member; and turn them in to Princeton (which had agreed to this somewhat unusual arrangement in view of the somewhat unusual circumstances). My thesis was to be on Quantum Electrodynamics. ...
    But, as this writer learned from attending a year of Oppy's lectures (1946-47) at Berkeley, and eagerly studying his printed and spoken words for several years thereafter, Oppy would never countenance any retreat from the Copenhagen position, of the kind advocated by Schrödinger and Einstein. He derived some great emotional satisfaction from just those elements of mysticism that Schrödinger and Einstein had deplored, and always wanted to make the world still more mystical, and less rational. ...
    If this meant standing in contradiction with the Copenhagen interpretation, so be it; I would be delighted to see it gone anyway, for the same reason that Einstein and Schrödinger would. But I sensed that Oppy would never tolerate a grain of this; he would crush me like an eggshell if I dared to express a word of such subversive ideas. I could do a thesis with Oppy only if it was his thesis, not mine.

    http://bayes.wustl.edu/etj/etj.html
    Oppy is Oppenheimer.

    Quantum mechanics works, there is no question about it. The question is why does it work. IMHO, the majority of physicists today are backing up the wrong tree -- the copenhagen interpretation. Further progress is, thus being hindered.

    --
    "Fighting terrorists with millitary might is like killing a mosquitor on your Dad's forehead with a rifle."
  4. And it's evolution that's hard to swallow? by misanthrope101 · · Score: 5, Interesting
    This subject is why I always sneer a bit when I hear/read a 'concerned Christian' pontificating on the unscientific nature of evolutionary theory. You find dozens and dozens of pages of closely worded arguments slicing the meaning of words ever so closely, delving deep into semantics and epistemology to show that evolution isn't really science, that methodological naturalism doens't really follow the evidence wherever it may lead, and so on. But the sound and fury are only heard concerning evolution--I have yet to see any of these ur-skeptics pop up with "how can you treat a theory as fact? why are you lying to our children" when the topic is any other branch of science.

    The real kicker is that evolutionary theory makes sense on an intuitive level. Random variation + natural selection = genetic change. Genetic change + time = a lot of change. Divergent change = speciation. I'm no scientist--I'm not even that bright. But the ideas are simple and elegant if you make even a token effort to understand. Not so with quantum mechanics. It means what again? If any thse creationists or ID advocates were actually moved by their supposed skepticism about methodologial naturalism, they would be up in arms about quantum mechanics. Instead you hear what from them? Silence. The only branch of science that their profound, deeply conscientious, implacable intellectual integrity can concern itself with is the only one that has implications for a simplistic reading of Genesis. Every time I read "I'm no creationist, but I can't stand by when our children are sold half-baked theories as fact!" I want to crack up laughing. Quantum mechanics is such an easier target because maybe 50 people worldwide really understand it (okay, I'm exaggerating, but by how much?) and high school teachers probably don't make a large percentage. If the issue were just the nature of methodological naturalism, or the limits of human knowledge, or the nature of science, then evolution would never be the easiest target. But as it is, it's the only target.

    Perhaps I'm coming late to this realization. Despite my noted cynicism, the very act of debate requires a little respect for the opposing view. But if the opposition is just flat-out lying, not only about their facts, but about their very motivating premises, then what is there to talk about? I guess it had to come to this eventually--if the other side really thinks you are working for the devil, you can't help but call them kooks sooner or later. What else is there?

    No, this post o' mine didn't address quantum mechanics. It's just that the sheer inscrutability of the subject (to me) got me to wondering--where are all the gadflies who normally come out of the woodwork with dire warnings about passing off rank theory as fact? Where are the lessons in the scientific theory, the exhortations to "prove" it before we poison the minds of the next generation?

  5. The other explanation by couch_warrior · · Score: 5, Interesting

    This article, in it's attempt to maximize the "weirdness factor", ignored what I find to be the most palatable explanation of quantum uncertainty. That is that the universe is five-dimensional. What makes everything seem so wierd is that we are not neutral observers. Our conciousness is created by phenomena that only exist when confined to a three-dimensional snapshot of that universe. We percieve the fourth dimension as time, because it allows our three dimensional snapshot to change as we move in the fourth dimension. We perceive the fifth dimension as probability because it allows multiple possible paths into the future. When an experiment, like determining the spin of one electron out of a pair of emitted electrons shows a particular outcome, the spin of the other particle is not magically changed. Instead we are simply determining which of two possible paths into the future our three-dimensional snapshot of reality happens to have taken. When we compare our results to a distant test of the spin of the other electron, we are not experiencing super-luminal communications, we are simply limited from seeing any other spin for that electron because of our limited three-dimensional conciousmess which can encompass only one state for that particle, which has to be compatible with the state discovered for its fellow electron.

    The real surprise here is how very limited our intelligence is, and how little of the true universe we are able to percieve. It is a terrible conceit to believe that we are a neutral observer capable of impartially observering the universe. We literally create our reality by observering it because our reality is a tiny three-dimensional slice of all possible realities. The universe isn't weird, we are just hopelessly myopic.

    This interpretation has the benefit of proving Einstein right. God does not play dice with the universe. Since it is commonly accepted that God would transcend the Universe, his conciousness would be at least five-dimensional. He would be simoultaneously aware of all possible paths into the future. When we pick one, we experience a true free-will choice, but the transcendent observer knows which path we will pick - without affeting the nature of the choice iteself. As a side benefit, free will and omniscience are reconciled, and one of the major arguments against the existence of God crumbles into dust.

    We aren't programs in the Matrix, we are ants in an ant farm - trapped in a tiny little slice of reality.

    --
    "Sic Semper Path of Least Resistance"