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My diabolical scheme for Quantum Immortality

  1. Mar 6, 2012 #1
    Hello all!!

    This is my first post here. I must have been living in a cave to not be here earlier, but such is life. Anyhoo, onwards!!

    I place myself inside a large Schrodinger's Box and launch myself into space, immediately after which the whole of earth is wiped out in a freak accident. If there is no one around to observe the collapse of my wave function, does this mean I will be (theoretically) immortal? Or at least both dead and alive simultaneously ? At least till intelligent life elsewhere in the universe is aware of my presence???

    I am basing this off my (limited) understanding of the Copenhagen Interpretation of QM and Counsciousness -caused- collapse.

    Thanks in advance!
  2. jcsd
  3. Mar 6, 2012 #2
    What exactly is with all these new people joining within days of each other, and posting these kind of questions (references to the teleportation thread yesterday)?
  4. Mar 6, 2012 #3

    I am a lone wolf, I assure you. Or we are all from the future here to warn you about Skynet.

    Stupid jokes aside, I really believe I have a fair question. Renninger negative-result experiment tells us that we dont need 'detection', as long as we have an 'observation'. If by 'observation' consciousness is implied, then is my question not reasonable? (within the realm of QM anyways)

  5. Mar 6, 2012 #4
    Consciousness has nothing to do with wave-function collapse, regardless of the misleading connotations of the term "observation." The universe functioned identically to how it currently does long before humanity evolved.
  6. Mar 6, 2012 #5
    So what does it mean by observation? Interacted with?
  7. Mar 6, 2012 #6
    Look at this book (page 161) to see how Renninger negative-result experiments can be explained without reference to conscious observation.
  8. Mar 6, 2012 #7
    I fail to see how that is the case. How do we know no collapse has occurred prior to knowing what the spin is?
  9. Mar 6, 2012 #8
    I wasn't saying that a consciousness-causes-collapse explanation is ruled out. But people often assume that unlike other phenomena in quantum mechanics, the Renninger negative-result experiment cannot be explained without conscious observation. I was just pointing out that even Renninger experiments can be explained via decoherence.
  10. Mar 6, 2012 #9
    I don't see any explanation of decoherence in that experiment on page 161.
  11. Mar 6, 2012 #10
    Quoting from the text:
    In other words, for a Renninger negative result the particle still gets entangled with the detector, and then we can explain the appearance of wavefunction collapse in the usual decoherence way.
  12. Mar 6, 2012 #11

    So essentially, consciousness is not really necessary for wave function to collapse? Nice. That clears up a few cobwebs in my brain.

    So what would constitute an 'observation' in my case?
  13. Mar 6, 2012 #12
    Ah I see. decoherence as in with the apparatus, not environment (I associate decoherence with interaction with environment).

    Yes, that is an explanation, but part of many that try to solve the measurement problem. Of course, if the macroscopic object is quantum mechanical, then you have issues. If you modify the Schrodinger equation, you don't generally have an issue (except it doesn't get completely localised into one definite state - as far as I've read).
  14. Mar 6, 2012 #13
    Decoherence is about how when you have large numbers of particles interating, so that the interference effects becomes smeared out and you get the appearance of wavefunction collapse. But decoherence does not explain genuine wavefunction collapse if such a thing exists.
  15. Mar 6, 2012 #14
    We are talking about decoherence with the environment. The whole reason why the pointer basis of the detector arises is because of environmental decoherence. See here for an explanation of the pointer basis.
  16. Mar 6, 2012 #15
    physics.x2010, here's a post of mine from another thread that you might find interesting:
  17. Mar 6, 2012 #16


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    While you may or may not be both dead and alive simultaneously, in the "alive" box your life will continue as normal and, optimistically, you will die of old age.

    After 100 years, you will be dead in both boxes. One wavefunction will represent a guy who's been dead a few years and one will represent a guy who's been dead for many decades.

    Sorry to disappoint.
  18. Mar 6, 2012 #17
    All the molecules in your body are constantly being measured or interacted with by each other and random forces, and I also don't think you understand these wave mechanics. Debroglie only proposed the Cat-in-a-box thing because he demonstrated that that was NOT how quantum mechanics works on the macroscopic scale. Your body doesn't have a single wave function because it's not a single particle, it's many small particles whos probability density is practically 0 at visible distances and the phenomena of superposition is not to state multiple realities are happening at once, but that the location is undefined or does not exist at a specific localized point, much like a classical wave. Your cells will age, and that's about it, chances are your going to die, though you'll probably run out of fuel and freeze or run out of O2 before you die of old age.
  19. Mar 7, 2012 #18
    Thank you for your response everyone !!

    I was having problems trying to resolve QM in the macroscopic scale. It is nice to be here, and hopefully I will learn enough, soon enough to help contribute to fruitful discussions soon.

    Thanks !!
  20. Mar 7, 2012 #19
    How does a person become a quantum object, a part of a quantum event? Which, incidently, requires a measurement result. (This is what Bohr called closure.) I see nothing in the postulates that require a conscious observer, or anything about a collapsing wavefunction. A quantum experiment does require a measuring device, but you have not even specified what it is you are trying to measure.

    But, assuming that you have been substituted for Schrodinger’s cat and that we are to observe whether you are alive or dead, as is done with the cat, we have only the following: (Remember that this is not classical physics.)

    Assuming you have the same state vector as the cat, all we know is that when the observation is made, you have a 50% chance of being found alive and 50% chance of being found dead. That’s all really know about your unfortunate situation. No one has ever seen a cat that is both alive and dead at the same time, so there is no evidence suggesting that is your fate.

    Quantum mechanics is silent on your condition prior to measurement. In fact, it is generally accepted that quantum objects do not exist without a measurement result. When we assume otherwise, as in the EPR experiment and in Bell’s theorem, we get incorrect results.

    There is no theory, classical or quantum, to help me answer your question about immortality.
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