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Quantum theory, consciousness and existence

  1. Apr 6, 2007 #1
    Hi everyone

    I'm currently readig Bruce Rosenblum & Fred Kuttner's book Quantum Enigma: Physics Encounters Consciousness and studying to be an NLP practitioner as well as practising tai chi. There are lot more parallels in these three areas than I imagined there would be. I have a few questions being thrown up of an existential nature and hope you guys might be able to help...

    I remember studying the Schrodinger's cat idea. What is most amazing is that quantom theory doesn't stop where Newtonian physics begins. So an electron, say, might be in one place or many places at once, but it is only observing it that makes it have a definite location.

    My first question is: How does it know we're observing it? What is it about the experimental system that gives the 'electron' the awareness to be in that place. Why does it not be in many or no places when we observe it?

    So, this phenomenon can be scaled up to anything, like Schrodinger's cat. Schrodinger says that the cat will either be alive or dead when we open the box, but why is that so. Here's my second question: would the cat not be somewhere else or in many places at once? Why does putting a cat in a box create a closed system? Surely quantum physics doesn't doesn't allow this...

    My third question is: How does scaling up mean that the cat would be alive or dead, rather than in different places?

    OK, so if the cat is alive when you open a box, that implies a whole histroy that leads up to that point. Similarly, if the cat is dead, then there is an alternative history that preceeds the moment of opening of the box. My fourth questions is: What are the implications for our perception of time? Does quantum theory suggest that time doesn't exist in a linear cause and effect way? Does all time exist now and it's just our brains that give it a linear frame to make sense of the world?

    Finally, part of NLP is studying time-line therapy. The idea is that if you go back to the root of an idea or perception, you can change how the words around that thought are anchored and how you feel about it. All the links and memories made from that point onwards will also be changed. So say you have a foot fetish and you pinpoint a time when you really loved playing with your mother's shoes. If you change your words ( and therefore feelings) that desrcibe that memory, all the rest of your memories about that stimulus will change too.

    If there is no linear time, surely there is no need to do this psychologcal dissmantling. Everything that ever has happened and will happen is happening right now. If I change the way I think about something 'now', the 'past' and 'future' of that thought will change too and we will never know the difference. My final questions are: Does this mean that my possibilities are limitless and my only constraints is the language (or software) used to describe my world? Is so, how does that fit in with those around me who witness a person with a linear evolving timeline rather than one where 'past' and future' change moment to moment?

    By the way, I'm not having an existential crisis, honest... but would like to hear your thoughts on these ideas.

    Thanks

    Viv
     
  2. jcsd
  3. Apr 6, 2007 #2
    Quantum theory is confusing enough even you understand something about it. I wouldn't recommend getting too deep into quantum world without willingness to also study it properly.

    But one of your points is clear enough that I think I can say something to it.

    Opening the box does not have any affect on the history. The cat is in superposition of being alive and dead until the box is opened, and after this it is not in a superposition anymore. Or this is at least how it is in the standard quantum theory. You can of course ask how a big thing such as a cat can be in a superposition in such way, and that is the Shrodinger's paradox, but that is a different story.

    It seems you have some other ideas of your own, and want to see a connection between them and quantum theory. I wouldn't encourage on that way.
     
  4. Apr 6, 2007 #3
    Hi Jostpuur

    I appreciate your reply, but what is a 'superposition'? The idea of the cat being alive or dead requiring a history to it is from the Rosenblum and Kuttner book. It also seems logical that is something is alive or dead there must be events leading up to that.

    I'm a little bit put off my your tone though. I studied Physics at GCSE, A Level and as a basis for my Biochemistry degree we covered the basics of quantum physics.

    Plus many physicists are now making connections between quantum physics and philosophy. After all, quantum therory throws up the biggest suprise to how we perceive the world since we realised the Earth moved around the sun.

    My questions seem reasonable enough... can you not explain any further points you understand?
     
  5. Apr 6, 2007 #4
    I am aware of this fact. I practice some related philosphy myself too :wink:

    There are a complex amplitudes for cat being alive and dead. For example, it could be that cat is alive with amplitude [tex]1/2[/tex], and dead with amplitude [tex]\sqrt{3}/2[/tex]. When you open the box, the squares of these give the probablities. In this case cat would be alive with probability [tex]1/4[/tex], and dead with probability [tex]3/4[/tex]. That is superposition, roughly.
     
  6. Apr 6, 2007 #5
    ok ill try to answer some of your questions, Im only in my first semister in QM though.
    Q1) How does it know we're observing it? something "knows" its being observed when it interacts with something else. ie when a photon (light) hits the electron. Also it cant be nowhere because QM is a space (X,Y,Z) probabilistic theory and the probibility of it being knowwhere might would have to include a time probability (ie the partical has changed form ect.)

    Q2-3)These questions are formed from a missunderstanding of what happens in hte story of Schrodinger's cat. http://en.wikipedia.org/wiki/Schr%C3%B6dinger's_cat the read is a little rough but google Schrodinger's cat and you find a good version for what ever techinical level you are at.
    A short clarification: the cat being dead and alive is the same as a cat being in 2 places. imagine a dead cat, now a live cat, these 2 cats can't be in the same place other wise you would have a walking dead cat or a live cat that had no heart beat and isn't breathing.

    Q4)Does all time exist now and it's just our brains that give it a linear frame to make sense of the world? no QM does not say this.
     
  7. Apr 6, 2007 #6
    wizardsblade, particles are always interacting with each other and yet not being measured. I dont think anyone has a good answer to why something "knows" it is being measured, it seems to imply some deep relationship between observers and the physical world. Some people have taken this as proof that consciousness exists, since only conscious beings can collapse the wavefunction. This brings many more questions though, can an animal collapse the wavefunction? Can a bacteria?
    QM may not say that all time exists at once (as far as I know) but relativity seems to be that way, there is no evidence from physics that time does indeed flow, perhaps it is an illusion.
     
  8. Apr 15, 2007 #7
    Remember, if I am not mistaken, that the cat analogy was Shrodingers way of pointing out the absurdity of the whole observer/wave function thing.

    I'm kinda thinking that a race of highly advanced beings, probably OURSELVES at some point thousands or millions of years in the future, having the capability to create universes/realities with ease.

    What I'm saying is that this life is probably some sort of three dimensional form of entertainment for our future selves. In that respect, it could very well mean that we are alone in this particular universe and that may be just one aspect of its particularly intended purposes. No big deal, since universes would be a dime a dozen.
    Other "entertainment" universes may be full of aliens. It all depends on which ride you decided to go on.

    This would go towards explaining why humans have such a fascination and a rapport with art, movies, tv and play acting. Its because instinctually there is that connection with knowing subconsciously what the truer reality of our nature may be
     
    Last edited: Apr 15, 2007
  9. Oct 27, 2011 #8
  10. Oct 27, 2011 #9

    BruceW

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    Hi Viv C,

    I'm glad you're interested in quantum mechanics (QM). Its always nice to see that someone finds physics interesting (because then it makes me feel more normal)!

    Right, your questions are mostly on the interpretation of quantum physics. There are many different interpretations of QM, and each says something different about what is 'really' going on. I will answer your questions using the most commonly accepted interpretation. This is the Copenhagen Interpretation (CI). And to be specific, it uses the idea of a non-unitary subjective collapse.

    1)Why does the electron be only in one place when we observe it, and how does it know to do this?:
    According to CI, the answer is really justified by thinking the other way round. We define an electron to be a particle that has definite position when we measure it. So when we make a position measurement, then we must get a definite answer. If we don't make that position measurement, the electron doesn't need to have a definite position.

    2)Schrodinger's cat is a useful thought experiment, where the cat is killed (or not) by some quantum event. Therefore, from the perspective of a person outside the box, the cat is neither definitely dead or alive. It is only if the person opens the box that the cat is definitely either dead or alive. And from the cat's perspective, it definitely is dead or alive, even if the person hasn't opened the box. This is because CI uses subjective non-unitary collapse. (Emphasis on the subjective). In practice, making such a box which is a closed system would be pretty difficult (maybe impossible). But the principle is still valid.

    3)The dead/alive example is just to give a shock factor to someone thinking about it. We could use some other observable for the example.

    4)What does quantum theory say about time?:
    Not much really. There are even relativistic formulations where time is just one of 4 'spacetime' dimensions. So there is nothing special about time in QM.
    When a measurement is made, a non-unitary subjective collapse occurs. This causes the system to change in a way that cannot be predicted beforehand (although the probability of a certain outcome is known). So for this reason CI is a non-deterministic theory.

    About your final questions: I'm not totally sure what you're talking about.
     
  11. Oct 27, 2011 #10

    Ken G

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    I can give you my reactions, but note that the questions you are asking are not answered by quantum mechanics, they are only answerable if we adopt some subjective interpretation of quantum mechanics. The interpretations vary, and so will the answers as a result-- quantum mechanics only tells us how to predict the outcomes of experiments, not the answers to philosophical questions like you are asking.
    Of course the electron doesn't know it is being observed, so your question is really, why is an observing environment different from a non-observing environment? I would turn that around-- the question is not why is an observation different, it is what needs to be different about the environment to qualify as an observation. I would say that has to do with how we think-- and what we call physics. We make certain choices about what we will regard physics as being, and contingent on those choices, we get the concept of what are the environmental requirements for something to count as an observation. Among them is, a complicated enough instrument has to become involved, such that the information we are tracking, and calling "physics", is a very tiny subset of all the information available in that instrument. Also, the decision not to track, as part of physics, most of that information is apparently what ends up giving us a sense of a "definite outcome" to the observation. That is key-- when there is no observation, there is no definite outcome. Indefiniteness plays a huge role in quantum mechanics (google the "quantum zeno effect" to find out why indefiniteness is what allows for anything in quantum mechanics to undergo any kind of change).
    Again, turn the question around-- we don't count the interaction as an observation of position unless the electron is found to be in just one place. So the question is, why does reality exhibit a kind of duality between the electron being in lots of places while it is dynamically evolving, yet we also have access to ways that make it show up in one place, and we call those ways a position observation because that's how we do physics. Again this is the key duality between indefiniteness and definiteness, that is a crucial element of how quantum mechanics works.
    As has been said, the key concept here is that of "superposition." You must begin your understanding of quantum mechanics there. You say you learned some QM already, but if they taught you something about QM but didn't teach you what a superposition is, then they had a strange idea of what "something" means in QM!
    It's not a fundamental distiction-- presumably being alive or dead has something to do with the locations and motions of the constituents. Aliveness is a joint property of the particles, location/movement is a particular property of each particle. You can observe the cat as a whole without observing its every particle-- indeed observing its every particle would probably require destroying the cat completely.
    Quantum mechanics allows for any of those interpretations of time. In QM, time is just a mathematical parameter in the theory, it has no physical meaning at all until we give it one. What meaning we give it depends on how we think about time, and would be consistent with any way we think about time that works for us.
    Why would you require that that particular technique depends on the existence of linear time? If the technique works, or doesn't work it makes no difference how you imagine it works. All that matters is that you test, honestly and double-blind, whether or not it works.

    In other words, if it does work, I can think of ten reasons why that might be, given any model of time you like. Or, if it doesn't work, I would simply interject that we should not expect anything to work until we have demonstrated that it does. Otherwise, we are in danger of being "quacks." The basic definition of a quack is someone who bases treatments on what they think will work, without relying on any demonstrated evidence that it could or should work.
    I would say the language doesn't make it true, evidence that it is true is all that can do that. There's the proper constraint on your language. But when the evidence allows for different languages, as is often the case in physics, then you may use any language that you prefer, as long as you are clear that all the meaning of that language comes from the demonstrable evidence, and none of it comes from what you might like to believe is true. This is the first rule of science.
     
  12. Oct 27, 2011 #11

    jtbell

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    Necropost alert! :wink:
     
  13. Oct 27, 2011 #12

    BruceW

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    Ah darn. Well that was a waste of my time. At least I've got it straightened out in my own head a bit more.
     
  14. Oct 28, 2011 #13
    Hi Viv C,

    Quantum Enigma was the FIRST proper book on Quantum Mechanics intended for nonscientific audiences I got. I assume, however, you have the 2nd edition copy (the more recently published, this year). I've actually rung Bruce (not entirely sure why he gave out his home phone number to a stranger..., and have been in contact with him since then via email).

    Superposition is a consequence of the linearity of Scrodinger's equation. For example, if a system can be dead (we'll use the cat example), or alive (dead OR alive if described by Classical Mechanics), then 'dead and alive' is also allowed (BUT only allowed in QM).

    The idea of creating the history of the cat when observation occurs (I believe the example they use is putting a cat in a box, set up the toxian, etc, and leave it for 8 hours), then after 8 hours you observe the cat; it is now either dead or alive, and the appropriate history of the outcome observed is actualised - i.e. alive cat = hungry cat.

    If you wish to read further into Quantum Mechanics, may I suggest 'Sneaking a Look at God's Cards' (http://press.princeton.edu/titles/8006.html) or 'Quantum Reality: Theory and Philosophy' (http://www.crcpress.com/product/isbn/9781584887034;jsessionid=f87EFAqvnf1-tQwo+Gog7w**)

    I think you're in the UK? In that case, you can pick up new, cheap, copies of these books from The Book Depository (http://www.bookdepository.com/)
     
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