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Cause and effect redefined?

  1. Aug 20, 2003 #1


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    Just a weird thought to roll around in your mind...

    Suppose for a moment, in the spirit of certain out-there physical theories, that parallel universes exist. Suppose more specifically that for every possible permutation of matter and energy in the universe, there exist corresponding parallel universes. As I understand it, the 'many worlds' interpretation of quantum mechanics essentially espouses this view (not down to the last detail, but I believe they are essentially equivalent). Anyway, let's be a little bolder. Let's suppose that time is a 4th physical dimension linking each of these parallel universes. That would make each universe timeless, essentially a snapshot describing a particular permutation of matter and energy in a 3-dimensional space; the 'flow' of time would actually be movement in the 4th dimension from one snapshot 3D universe to another. The laws of physics, then, would not describe the changes in matter and energy in a dynamic world so much as they would describe the particular motion along the 4th dimension from one snapshot universe to the next that we human consciousnesses seem to be following. As far out as this sounds, I seem to recall reading that it was essentially the worldview of a relatively prominent physicist (if anyone can substantiate this, if it's correct at all, it would be appreciated).

    So... if the above were an accurate ontological description, wouldn't we drastically have to redefine our notions of cause and effect? The idea of cause and effect that we commonly hold would merely be an illusion generated by the particular path we are riding through a series of static 3D universes. So long as we suppose that this multi-universe space is interconnected with alternate traversable paths (which from our point of view would correspond to a dynamic universe with different physical laws, or perhaps with nothing resembling laws at all), there is nothing that makes our particular path anything special-- and therefore conclusions that we derive from it and hold to be absolute (eg cause and effect) are actually relative, and do not hold for the entire ontology of existence.

    Of course, to even consider this speculation requires abandoning some conventional ideas of cause and effect (eg that all existing things need a cause-- what 'caused' each permutation of the universe to 'exist'?). But the above paragraph goes further-- it calls into question the validity of our entire notion of the cause/effect relationship. We take it as a given, above all reproach, but even such a foundational concept is not necessarily foolproof. So what? Well, it's just a little shot of humility I guess. As an added bonus, you can pretty much summarily chop down any 'proofs' for or against the existence of God, since no assumption is above reproach beyond the limited scope of self-evident, subjective phenomena (eg "I am seeing the color I call blue right now" or "I think therefore I am").
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  3. Aug 21, 2003 #2

    Everytime someone questions the notion of causality, I feel like asking them why is it that my car won't start if I don't insert the key in the ignition? Or why the lights in my living room won't shine unless the switch is in the 'on' position?

    The proof that causality is real lies in reality. If we can't understand it, that's our problem. I think we should always refrain from projecting our ignorance into the objective world; just because we can't possibly imagine how it's done it doesn't mean it can't be done.
  4. Aug 21, 2003 #3


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    You are entirely missing the point. The proof that causality is real in the hypothetical situation I spelled out turns out to be an illusion. Is this hypothetical situation a true situation? Who knows, I wasn't trying to make any definite metaphysical claims anyway. My point was this: just because you can't possibly imagine certain things being different from how you conceive of them, it doesn't mean that these things are actually as they appear.
  5. Aug 21, 2003 #4
    Why is it that sometimes when you insert the ignition key, your car still does not start or your lights don't shine after you turn of the switch? Does that mean the our reality has changed, that we are now in a different universe?

    If the different universes are interconnected and can be traversed, wouldn't that mean that they are just different parts or regions or dimentions of the same universe?
    Last edited: Aug 21, 2003
  6. Aug 21, 2003 #5


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    If you define universe as the totality of existence, yes. But often we equate totality of existence with those parts of existence which we can observe. In this instance, what we conventionally call a 'universe' isn't all there is. There's a nice article on parallel universes on Scientific American:

  7. Aug 21, 2003 #6
    I'm not missing the point. The problem, in my opinion, is deeper than you realize. From my perspective, causality is neither real nor illusion. The term 'illusion' refers to an observer mistaking his imagination for reality, his thoughts for sense impressions. As far as I can tell, no one thinks the causal links we attribute to our experiences exist anywhere but in our imagination. To say "causality is an illusion" is akin to saying "dreams are illusions". Redundant and beside the point, if I may respectfully disagree.

    The real problem, as I see it, is that even after we understand that "dreams are illusions", we still don't know where the illusion comes from. We are certainly not making it up as we don't have the ability to dream at will. And the same goes for causality. It's obvious that "the light went on because someone flipped the switch" is just a story we tell ourselves; in reality we have no clue where the connection between "light switch" and "shining bulb" is. The scientific story about electrons, conductors, and energy conversion may be a bit more profound, but it's still a story nonetheless.

    So it's not enough to assert that "causality is an illusion"; you have to explain what causes the illusion. You have to explain why we never see our cars start without the key in the ignition, or the lights go on without turning the switch. Surely those things happen, but even the most skeptical person would rather believe in ghosts than in some radically different view of the cosmos. For at least we know something about ghosts, whereas we know absolutely nothing about parallel universes.
  8. Aug 21, 2003 #7


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    I did explain what causes the illusion in this hypothetical situation. It is that we are traversing a particular path through these series of highly related 'snapshot' universes as described by the laws of physics. The natural question then arises, what makes this path special? Are there other possible paths? If so, these paths define, from our perspective, either new laws of physics or some form of incoherent randomness. In particular, it is wrong to say in this paradigm that A causes B; rather, we would say that B follows A since we are on a path between snapshot universes where the transition is defined such that we will always travel from a universe where A occurs to one where B occurs. But the universe where B occurs exists independently of the universe where A occurs; the perception that A somehow generates or brings into existence B is an illusion. In reality, their existences are entirely independent. Thus, our conceptions of cause and effect in this hypothetical situation are faulty.

    There is an analogy we can make here. Suppose you have a series of static images of a stick figure, a ball, and a hill. In a particular rapid sequence of these images, it looks like the stick figure is pushing the ball up the hill; if this flipbook was our only outlook on reality, we might say the stick figure is causing the ball to go uphill. But this highly ordered sequence of images is not the only possible sequence; we can also imagine a sequence where it looks like the ball is pushing the stick figure downhill, or where it looks like the various figures are jumping around randomly like quantum particles. Apparent causality actually amounts to always seeing a particular sequence of pre-existing phenomena.

    And again, I'm not saying that these parallel universes exist. This is a purely hypothetical situation. My purpose for constructing it as such was to show a logically coherent situation where an unquestioned assumption or set of assumptions that we take for granted (eg for every effect there must be a cause, or causes bring effects into existence) turns out to be false. The bigger idea is simply that we should recognize that for all we think we know about reality, we could be fooling ourselves.
  9. Aug 21, 2003 #8
    No, we would not have to redefine causality. Words only have meaning because we give them meaning, not because they necessarilly reflect some kind of absolute reality. For example, take your argument to the opposite extreme of the utter randomness of QM. Let's say everything is in reality utterly random and cause and effect are merely illusions presented by our limited perspective. Does that mean that we must now redefine cause and effect as random? Obviously not, the words are still useful and meaningful as they are and to redefine the causal as the acausal is self-defeating and absurd.
  10. Aug 21, 2003 #9
    Several pioneer contributors to these ideas:

    Hugh Everett III - relative state quantum theorist
    Bryce DeWitt - many-worlds quantum theorist
    David Albert - many-minds quantum theorist
    Murray Gell-Mann - many-histories quantum theorist

    Gell-Mann is the most distinguished member of this group.

    the Everett FAQ
  11. Aug 21, 2003 #10


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    The words are still meaningful, but they imply an ontology that (in this situation) would be false. Thus, while we could still get away with saying A caused B for all practical purposes (like we can still get away with thinking of the world in terms of Euclidean geometry), if we were to use this conception in philosophical arguments we would be in error. We would be basing our argument on faulty assumptions, so the argument would not be sound. Thus, the 'redefinition' would only come into play when we think about the world philosophically, but it in this realm it would have a great impact. Analogously, I can get through life just fine without learning or thinking about quantum mechanics, but if I want to try to form a coherent idea of what reality is like, I'd better take QM into consideration.
  12. Aug 21, 2003 #11
    Wouldn't the sum of histories as developed by Feynman have the same result of doing way with absolute cause and effect at least at the quantum level? This would not require the multi-verse model to show the falicy of cause and effect. Which history is the cause is which effect history rather than which universe are we looking at or are in now? Does this bring your paradigm closer to our reality than jumping around different universes?
  13. Aug 21, 2003 #12


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    I think the QM approaches all lump together time and space as per GR. The result is a selection of time/space landscapes each describing the entire history of interactions in such an universe.

    But on the whole, QM doesn't really get on with causality. QM insists for example things like nuclear decay is absolutely acausal - the laws allow it to happen, but the fact it happens at a particular instant is without cause. Hence, cause and effect are an illusion, caused by the direction we take in the time dimension. As for conclusions we derive, we reach a general consensus that we share a path in time - the so called Arrow of Time - causality is hence a statistical measure. We do not "pick" a universe, but exist in several simultaneously. The one of you I am talking to belongs to this one, and the others are no less real. And as for the physical theory, the universes cannot be traversed.

    But I don't think the many worlds interpretation removes physical laws. Rather, these laws have an influence on the probability of each even, or in the many worlds model how many instances has an event occured, and how likely you are to find yourself there. So with the right conception of cause and effect, it still features.
  14. Aug 21, 2003 #13
    Every noun and verb can be said to imply some sort of ontology. The Navaho language, for example, has no future tense, no verb "to be". Thus, even our use of the simple verb "to be" implies an ontology. What matters, demonstrably, is the function of words in a given context rather than their implied ontology.

    You can construe whatever you want from words, assume whatever context you want, but that is besides the point. No matter what language you devise, it will possess an implicite ontology at the very least. Each language has distinctive pros and cons and, in the case of english, it is particularly good for engineering. Rather than sacraficing this advantage for dubious reasons, it is easier to just be careful to express distinctive contexts as they arise.
  15. Aug 22, 2003 #14


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    I don't think you've contradicted anything I've said. Engineering, for example, is a practical enterprise. Considering that cause and effect may not operate as we conceive of it on the most fundamental existential level would not necessitate a change in our conception of cause and effect with respect to the particular existential circumstances we find outselves in; for instance, in my hypothetical situation, cause and effect works just fine for the existence we find ourselves in, although it would merely be a special case and not true in an absolute sense. Where it would make a difference, however, is in our conception of and reasoning about the fundamental nature of reality. As this topic is only the concern of philosophy (not science, since science only concerns itself with empircally verifiable claims), any such reconception of cause and effect would only apply to philosophical domains.
  16. Aug 22, 2003 #15
    I think what we're addressing here, is something I like to think of as a fundamental flaw of physics and it's beliefs. Or perhaps it's only the way those philosophies are being followed. Physics and other sciences follow the belief that if it cannot be observed, that it is not possible. Lack of observations precludes possibility. There's not allowance for the abstract, non-physical universe. It's a theme I see recurring on these boards time and time again. Why is this? No we can't prove there is a multiverse. Does this preclude the possibility, even following logic? No, unless you ascribe to the belief that if it can't be seen, touch, tasted or smelled, then it's not possible. We're only at the beginning of our understanding of time as a seperate demension. So we cannot preclude this as a possibility simply because we cannot prove it. Would it follow logic and the laws of physics as we know it? To a degree. I just cannot understand the obstinance.
  17. Feb 21, 2004 #16
    pinpointing my view.

    I would like to thank Hypnagogue for this thread. In his first post he pretty much nailed my suspicions about how the universe functions. I have stumbled onto this thread by searching the web for explanations for acausality of nuclear decay. Would anyone point me to some good sources about that or try to explain it a bit?


    Zebbler (an art school student from Boston)
  18. Apr 3, 2004 #17

    I think you are describing what is called a 'block' universe if I remember right, one in which everything and every 'event' exists at once. Somebody (Wheeler?) likened it to a pack of cards in which every card is a snapshot. The cards don't change but conscious beings sort of riffle (rifle?) through them.

    The interesting issue is that a multiverse theory of the type you describe seems to make consciousness a central and decidedly causal player in the unfolding of our universe.

    As I understand it the Copenhagen Interpretation is on its way out and multiverse theories are getting a new lease of life. I prefer hidden variables myself but even this calls into question our usual ideas of causality since at a QM level effects cause causes as much as causes cause effects, they just work in opposite time directions, and non-locally at that.

    Anyway re. multiverses the big question seems to be what is it that determines which universe we (individually) will be in next.
    Last edited: Apr 3, 2004
  19. Jun 2, 2004 #18

    Probability is only proven relative to a sequence of instances.

    Within eternity, most likely outcome is a measure of inversally proportional probabilities where all oposing outcomes are equally possible (and therefore, 'are')

    Every instance is a possibility, just some are more probable than others. All instances(universes) exist in eternity (infinity or sub-consiousness). The sub-consiousness sees a possible link of instances and trys to manifest them, but only the most probable seem to occur. Probability is found through repetition of coinciding instances through a relatively percieved time direction. For any instance point, there is no time since time is simply the travel of a subconsiouce from one instance to another. All instances simply 'are' in eternity(infinity). If one were to apply the populary misunderstood notion of time to a particular instance, then one could say that that instance 'repeats' itself infinitely, as does a sequence of instances. It is within these sequences, that probability is found. cause=effect, effect=cause, but only the most probable!, in any direction of time! In a percieved past to future direction of time, probability of an instance changes at an infinite rate as new instaces appearing bring along with them more options of probable futures. Therefore you might infact end up where you set out for, although perhaps you got there through a completely unexpected turn of events.

    As every instance 'is',-- eternity = perfect chaos = randomness = infinity.

    As every sequence of the infinite instances 'is',-- probability of next instance = order within the chaos = patterns within the perfect randomness
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