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Blindness and wave collapse

  1. May 8, 2006 #1
    Can blind people collapse the wave function or is the wave collapse restricted to the sense of sight? Can other senses such as smell, taste, hearing and feeling collapse the wave function? Does the wave function only collapse on the surface of an object?
    Thanks RAD
  2. jcsd
  3. May 9, 2006 #2
    Wave function colapses when it is measured. 'Measured' is a fairly undefined term. But it is stupid to assume that measuring only pertains to what we see.

    Also I think maybe this is the wrong forum for this.
  4. May 9, 2006 #3
    I was reffering to the paradox of Shroedinger's Cat in which the thought experiment uses the sense of sight to conduct the measurement. The idea of sense collapsing the wave function came from a book (A book on physics and philosophy) and is not my idea. If a conscious being does not collapse the wave function then it must be a purely mathematical abstraction.
  5. May 9, 2006 #4
    A wavefunction is an algorithm for determining probabilities. It has NOTHING to do with human vision, consciousness, or blind people. Your philosophy book has mislead you.

    I've sent a PM to loseyourname, this thread really belongs in the QM forum.
  6. May 9, 2006 #5
    Here is from the book

    The hypothesis of wave-function collapse by conscious observers raises a number of questions. First of all, does 'observation' refer solely to the sense of sight or do our other senses -- taste, touch, smell, and hearing -- also possess the power to collapse wave functions? If not, how can the superiority of sight be explained? Can clairvoyant vision, or distant viewing, also collapse wave functions? When we collapse our own bodies' wave functions, must we actually look at ourselves (assuming that it is not too dark, or that we are not blind), or is it sufficient to be aware that we are alive? Is it in fact possible to collapse the wave function of an object just by thinking of it?

    When we look at an object we normally only see part of its surface, but apparently this is sufficient to collapse the wave function of the whole object. If an astronaut observes our earth from space, does this automatically collapse the wave functions of everything living on it? And where exactly does the boundary between the earth and its surroundings lie? The rocky earth is surrounded by an atmosphere, which merges into the interstellar medium. In fact, if everything is constantly exchanging matter and energy with its environment, and is directly correlated with everything else, would not an observation by a single selfconscious observer collapse the wave function(s) of everything in the universe

    It sounds to me that wave collapse is just a mathematical abstraction and has nothing to say about reality,
    Last edited: May 9, 2006
  7. May 9, 2006 #6
    I know, and my point is just because they used sight to preform the measurement in the thought experiment doesn't mean that the measuring only pertains to sight. Since it doesn't only pertain to sight, it is silly to say that a blind person cannot collapse a wave fuction.

    Edit: By the way your book is probably written by someone who doesn't know what they're talking about. Duality of states only occurs at the quantum level, and the collapse only occurs when something is consious(sp?) of it's state. For instance our naked eyes cannot see things that small, and our brain cannot comprehend it so there is no consious understanding of it's state, so no collapse can occur. So saying that looking at the earth would collapse everything on it is not only false logic, but it's stupid.
    Last edited: May 9, 2006
  8. May 9, 2006 #7


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    Yah from what I know, wave-functions collapse when ANYTHING measures them, human or not.
  9. May 10, 2006 #8


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    Moved from General Philosophy.
  10. May 10, 2006 #9


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    Ultimately, all of your senses are based in electromagnetism anyway so the question of "seeing" vs. "non-seeing" is moot.
  11. May 10, 2006 #10
    Aren't you putting the cart in front of the horse? According to the empiricists (and there are many), physics concerns the regularities in our experience of what we call "the world".
  12. May 10, 2006 #11
    At last someone talks sense. But probabilities of what? Measurement outcomes, to be sure, but how do we define them? See the discussion in https://www.physicsforums.com/showthread.php?t=116582".
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  13. May 10, 2006 #12


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    Apparently it is unbecoming for a physicist to be "concerned with the regularities in our experience of what we call the "world." But it's a dirty job, and someone has to do it. (I'll admit to making an inference or two in my first sentence.)

    If there ever was an award for garbled, troubled, imaginative discussions, those dealing with "wave function collapse" - cf post 5 - would be right up there. The other award, probably year-after-year, would be for the "Strawman of the Year."

    Rach3 -- Is there physics when there's nobody to contemplate a splendid universe, let alone measure anything?

    Am I correct, then, that Einstein's observers and their events somehow vanish into empty vacuum when atomic dimensions are at issue?

    Could you have an algorithm without consciousness?
    Reilly Atkinson
  14. May 11, 2006 #13
    Schroedinger's Cat

    I don't know much about mathematics but from what I have read about Schroedinger's Cat the wave function collapse is supposed to apply to macroscopic objects as well as quantum objects. I know at first glance this thread may sound absurd but what role does consciousness plays in quantum physics? After all we are all made of quantum particles and we cannot talk about quatum phenomena without at the same time talk about ourselves.
  15. May 11, 2006 #14

    Most of the people around here are a lot smarter about this than me, but since they ain't posting answers .. I'll try to.

    As far as I can see, this whole "conscious observer" thing rests on 2 dubious concepts: "Superposition" and "Collapse of the Wave Function". They're OK if you treat them ONLY as mathematical tools. But some go as far as giving them physical meaning, i.e., "particles ARE in a superpositon of states before they are measured", and "when a measurement is taken, the particle collapses into 1 of 2 different allowed states".

    That, along with what it means to "take a measurement" has no agreed upon definition. The CI (Copenhagen Interpretation of QM) doesn't even try to answer that one.

    It all leads to Schroedinger's Cat in that each and everybody in the Universe is supposed to have to take their own measurement before the state of any one or a conglomeration of particles is set for that person (the cat may be dead for you, but since I haven't looked it's either alive or dead for me .. its state is only realized for me when I look at it.)

    Paul Dirac wrote a book on this in 1930 called "The Principle of Quantum Mechanics". There is a chapter in it where he writes about "Superposition and Indeterminacy", and states that it can be misleading to think of "Superposition" in a classical sense. And that's exactly how it is being thought about by persons who give them physical meaning. The book's a good read if you could find it in a library.

    If you simply deny that "superposition" has a physical meaning, and define a measurement as "when 2 particles interact", the mystery of Schroedinger's Cat goes away. It's dead (or alive) for each and every person even if they don't look at (or smell/sense) it.

    That's my take on it. Others will disagree.
    Last edited: May 11, 2006
  16. May 11, 2006 #15


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    Wait... For people who do not think that there are effects that are attributed directly to the superposition phenomenon, then please produce an alternative explanation for (i) the bonding-antibonding bonds in H2 molecule (ii) the coherence gap observed in the Stony Brook/Delft SQUID experiments.

    Till you can show me a valid alternative scenario that can be published in a peer-reviewed journal, all of this dismisal of superposition as not being real is really empty, philosophical talk not backed by empirical evidence, y'know, the one that's required when we do physics!

  17. May 11, 2006 #16
    I like what you said ' Is there physics when there's nobody to contemplate a splendid universe, let alone measure anything?'

    Is the moon really there when no one is looking at it?
  18. May 11, 2006 #17


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    This thread should never have been let out of the Philosophy forum.

  19. May 11, 2006 #18

    Were you being serious, or tongue-in-cheek??!??

    Have any info on the "(i) the bonding-antibonding bonds in H2 molecule (ii) the coherence gap observed in the Stony Brook/Delft SQUID experiments." I'd like to read them.
  20. May 11, 2006 #19


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    Do you see me giggling?

    https://www.physicsforums.com/journal.php?do=showentry&e=88&enum=26 [Broken]

    I'd like to see people write a rebuttal to those papers and show where they can duplicate the identical phenomenon without invoking such superpositions!

    Last edited by a moderator: May 2, 2017
  21. May 11, 2006 #20

    Thanks, but I didn't see any links to the actual papers (not that I'd be able to understand them anyway) .. maybe I missed them though.

    I'll try to find them online, or maybe a trip to the library next week.

    Have you read the Paul Dirac chapter I wrote about?
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