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Please shred my quantum physics-gravity worldview

  1. Dec 4, 2008 #1
    I have always viewed quantum physics in a unique way. I am deeply convinced someting is very right about the view, and by virtue of my inexperience in math, something very likely wrong with any of the specifics of it. I am at a point in my life where I realize I can never attain the level of math required to explore this view fully, and was hoping some kind person with said math expertise might just be able to shoot a hole in the whole thing and I can live my life knowing the view was all for naught anyway.

    I find the traditional view of a particle in a quantum state being "observed" and then collapsing into a normal state to be hard to swallow. Particularly since the particle used to do the observing is in a quantum state until the point of observation and the immediately after. I can't help but think of the particles as constantly existing as a set of probability distributions for each of its properties. They exist in a perpetual quantum state, and the universe never "knows" that they're anywhere in particular, i.e. they cannot "collapse" out of their quantum state of their own accord.

    When you introduce another particle into the system, though, you have a combination of two probability distributions which can add up to a certainty that a particle must be in a particular location at a particular time. This "collapsed" particle is only observed at a point in space when the math going on in the background calculates a 100% certainty that there is a particle there. Basically if you observe particle A where it's 25% likely to be, it's because the observer particle you sent toward it generated a 75% likelyhood of the universe seeing it there too. Basically this observed universe is only compsed of the certainties of the combination of all the probability distrobutions of all the particles inside it.

    On gravity, I have always thought it simply must be a macroscopic net effect of collections of massive particles. One such effect I belive holds at least the principle of gravity is that if you have two collections of matter spaced a distance apart, the net probability of observing particles in the system is going to be higher in the space in between the particles. Basically if you take two probability curves and place them a distance apart on the number line and then graph the total probability of observing two particles in that syatem, you find that it's more likely to observe the two particles closer to each other than they were originally, and it becomes at more and more likely they will "move" (more correctly be found) closer together as time goes on. It stands to reason that if you take a heap of particles at one side, this effect will become stronger.

    Thank you for reading, and I am very interested in the physical or mathematical reasons why this is not completely correct. I look forward to any lively discussion this post might spurr.
  2. jcsd
  3. Dec 4, 2008 #2
    This is just my personal opinion, but I believe that any person with a good intellect can learn the mathematics if they have the determination to do so. The main constraint would be the limitations of one's time to pursue such an endeavor.

    The original view was the classical one. If we have information about some particle, then we know all of the past and future behavior of the particle. As an extreme consequence, we could apply this idea to the totality of universe and determine the its evolution with no ambiguity.

    The mainstream view is the statistical interpretation. A particle exists in a superposition of many states. It does not make sense to discuss its properties or to say it even exists unless we choose to observe it. When we observe the particle, we cause the wave function to collapse and the particle acquires some specific state--the statistical interpretation says that we have some probability of observing the particle to be in a particular state. This notion is why Einstein said something to the effect that god does not play dice. The problem is that the observer is part of the system under study and influences the behavior of the system. So while we try to keep our observations objective, we can't help but to introduce a certain level of subjectivity.
  4. Dec 4, 2008 #3
    Pure math will NOT get you to a definitive answer...that's been debated since Bohr/Heisenberg/Einstein and others debated over the years....

    While the first sentence represents one interpretation of the mathematics, I disagree almost entirely with the rest of the quote. Here is why: Particles are constantly interacting with their environment, everything else in the universe. It's difficult to keep them in a "pristine" state. Once information is exchanged the indeterminate nature of the quantum particle largely vanishes leaving "Heisenberg uncertainty" as a further condundrum.

    I may not understand your explanation or perhaps the explanation is imprecise, but as written, the above is just inconsistent with quantum theories. To say it another another way, Heisenberg uncertainty guarantees you'll almost never be able to locate a particle with perfect (100%) precision. And if that is not clear, one could say equivalently that quantum jitters prevent a particle from being confined and located with absolute precision.

    and from Buffordboy:
    To clarify, I don't think this has ever been a view of quantum theorists; exactly the opposite is the case irregardless of the specific quantum theory. "Classical' in his post means continous wave/field representation...not "traditional" as used in your question/post.
  5. Dec 4, 2008 #4
    Yes, you are right. When discussing the "original" view, I was referring to the view before the development of quantum mechanics. This definitely was not clear in my original post. Thanks.
  6. Dec 4, 2008 #5
    popular science need to be published with a disclaimer - "this book does not teach you anything." you want to know what QM is then study it in earnest which means know a little math. considering a decent high school student has enough math background to understand some of the simple problems it is actually very little math. don't worry about the philosophical implications about the postulates - solve some simple problems and you can make your own decisions about what QM really is.

    to me it's just treating particles like waves and that's it.
  7. Dec 4, 2008 #6
    to ice 109, I absolutely agree with you about waves and particles. the issus is that a particle act like a wave, and a wave like a particle. the quantum view, which is tainted by Schodingers' paradox, should be a polarised flat dimension one, where a wave looks like a charged particle because it is observed end on, like hair on end in response to static electricity, and a particle looks like a wave becuase we observe its transit, or passage. A more correct Einstein type experiment, would be to remove the two views from time, therefore freezing the moment, to truly see a wave and/or a particle ( point).
    a partial solution which would give two reference points where an observer under Heisenberg would be able to use a low gravity environment and subject at the speed of light, such as photons in an off-world lab.
  8. Dec 4, 2008 #7
    i should've been clearer

    a particle is a wave in the sense that it's description employs the same mathematics.

    that is what i meant.

    i personally do not think about quantum ( very very small, or more verbosely - at length scales where quantum mechanics is applicable ) particles in any other way than that. there is no physical intuition to be gained from making analogies . either you do/read the experiments or you trust the theory. there is nothing else.

    most of your post is lost on me but i will say that if i were to look for particle like qualities in a wave it would be in a wave packet.
  9. Dec 4, 2008 #8
    I don't think this holds up. If I dump a collection of pool balls in a room, they don't roll around randomly and eventually clump up in a heap in the corner. Neither, in a room, do you suddenly find yourself in a vacuum, because all of the air molecules have 'statistically collided' to one spot.

    In fact, even a star can't collapse during formation for this reason -- that is, what you are describing actually acts AGAINST gravity from time to time.

    Given a volume of gas held together by gravity, probability means it will try to spread out and maximize the amount of space it occupies; only gravity can hold it to a particular area. Collapse increases temperature, and temperature increases volume. Back to square one.

    Of course in the real world, the temperature also causes radiation -- the radiation drops the temperature, and the star can continue to collapse. Until fusion starts, of course. But that's another story.
  10. Dec 4, 2008 #9
    I think it was Planck who was talking about a dimension like a 2D paper which can be viewed side on, populated by particles which could either be lines or dots. i was agreeing with this, as much as when lines can be dots or dots, lines. At the scale of quarks, where they can be both/either or one or the other, it seems hard for me to disprove change by measurement unless by applied electromagnetic force. At the same time as quarks appear to have motion, charged attributes are measured in real time, and as traces. the compared results of two measuring experiments of these attributes, one on Earth and one in a low gravity lab, may be different enough to give determinate data. (sorry to be an glib earlier).
  11. Dec 6, 2008 #10
    You know, there is a new way to look at everything in QM. I would even say, an ultimate interpretation of QM had been finally found in early 199x.

    The Wavefunction *never collapses*. Instead, there is a mathematical process called http://en.wikipedia.org/wiki/Quantum_decoherence

    So we dont need all that weird "collapse" at all. The new interpretation is simpler but leads to even crazier things like alternative branches of the future - for example, in the Schoedinger cats experiment BOTH cats (dead and alive) exist.

    Even more, QM becomes DETERMINISTIC in the so called 'Birds's eye view', but for the observers (Frog's view) it appears to be random.
  12. Dec 6, 2008 #11

    Yes, that's right what you said about decoherence, but it's still the craziest theory i've ever heard in my life. It says that with each interaction the universe splits in all the possible outcomes of the interaction, creating trillions of universes every second. To me this would be the ultimate proof that the universe is virtual and that so are we(whatever "we" means when there are trillion copies of us in trillion universes).
    By the way, i'd sacrifice a finger from my left arm to hop to a universe where the dinosaurs survived, even if i might become a meal. Or hop to a universe where Jesus was not crucified or where he did not ressurect(is this possible??).
    Last edited: Dec 6, 2008
  13. Dec 6, 2008 #12
  14. Dec 6, 2008 #13
    I wanted to add that the current view on the quantum decoherence is different from the 'Many-worlds' interpretation.

    In the many-worlds interpretation the Universe always splits and never merges, while in reality all branches are still connected (even these connections are very weak for the microscopic observer), so the reality not only spilts but also merges.

    Interference is just an example when 2 branches merge. May be there is also an interference on the macroscopic scale...
  15. Dec 6, 2008 #14

    Yep, i suck at naming those great numbers. I was hesitant to use the word "infininite" in place of trillions just because the universe appears to have a beginning 14 billion years ago. This sets a practical limit to the number of possible "branched" parallel universes, even if they have to be 10^100 or more.

    BTW, decoherence is about losing interference, hence it's the opposite of decoherence. Do you have a link with this theorised interference between decohered universes?

    You might find prof. Michio Kaku really insightful on this topic(there is something about his line of thinking and wording that makes everything seem so obvious):

    " Today, there is still no universal consensus to the questions raised by Einstein back in the 1920s concerning the quantum theory’s outrageous paradoxes. But one idea is gradually catching on, and this is “decoherence.”

    For example, perhaps the cat splits into two cats or two universes. In one universe, the cat is dead. In the other universe, the cat is alive. So, at each juncture in the history of the universe, it constantly splits into two. The key is that we have “decohered” from these other universes, and hence can no longer communicate with these parallel universes. Nobel Laureate Steve Weinberg compares this to listening to a radio in your living room. You can hear many, many stations on your radio, so you know that there are many invisible radio waves permeating your living room. But your radio is tuned to only one frequency, and it has decohered from all the others. The radio frequency you are hearing no longer interacts with all the other radio frequencies, and you hear only one sound.

    Likewise, in your living are the wave functions of alternate universes. There are the wave functions of dinosaurs, pirates, aliens, exploding stars, etc. in your living room. But you cannot interact with these parallel universes. Your universe no longer vibrates in unison with them, and hence has decoupled from them. (So, perhaps in one universe Elvis is still alive, but you can no longer interact with that universe.)"

    Last edited: Dec 6, 2008
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