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James Putnam: "Paul, Before you score any points with me about avoiding derogatory..." in Hanny's Voorwerp, and...
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RECENT ARTICLES
click titles to read articles
The Cosmic Family Tree
Mapping the ancestral history of spacetime in an effort to unite quantum mechanics and general relativity.
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Why do we perceive time marching in one direction? In this classic article with new video, Craig Callender combines general relativity, evolutionary biology and cognitive science to bring the physics of time in line with everyday experience.
Pentcho Valev: "Eckard, The crucial assumption of Einstein's theory is that the speed of..." in Some-When
Eckard Blumschein: "Pentcho and Peter, To what degree do you agree on: "the crucial assumption..." in Some-When
Tommy Gilbertson: "Locomoting Whilst Minimizing Cost OxyMorons, Koans & Locomotion..." in The Secret History of...
Edwin Klingman: "Well this certainly stimulated some interesting comments. I'll take a while..." in The Secret History of...
Jason Wolfe: "Dear Sridattadev, If you are looking for Universal spiritual bliss, you..." in The Whole and Nothing But
Jason Wolfe: "Dear Paul, You said, "It is one thing to have a theoretical explanation,..." in Hanny's Voorwerp, and...
James Putnam: "Paul, Before you score any points with me about avoiding derogatory..." in Hanny's Voorwerp, and...
Lawrence B. Crowell: "I just can’t let this slide by! It was proven by Euler nearly 300 years..." in The Whole and Nothing But
RECENT ARTICLES
click titles to read articles
The Cosmic Family Tree
Mapping the ancestral history of spacetime in an effort to unite quantum mechanics and general relativity.
Behind the Shadows
Imagining Schrödinger’s cat peering out from behind a black hole could lead to a theory of quantum gravity.
Why Did Nature Choose Quantum Theory?
Schrödinger’s cat may help reveal while some physical theories are better at describing reality than others.
Video Article: Through a Glass Darkly
Eight-dimensional numbers could be needed to handle string-theory’s 10-dimensional physics. This classic article, with new video content, also tackles the mystery of why elementary particles come in families of three—and maybe even how spacetime emerges in 4-dimensions.
Video Article: Evolving Time's Arrow
Why do we perceive time marching in one direction? In this classic article with new video, Craig Callender combines general relativity, evolutionary biology and cognitive science to bring the physics of time in line with everyday experience.
FQXi BLOGS
February 9, 2012
At about 1 AM GMT on April 20, 2007, the Universe split into at least 32,768 nearly-identical copies. How? And did it really?
The event was precipitated by yours truly gathering a quantum-mechanically random number between 1 and 10,000. Generating this number required making at least 15 quantum measurements, each yielding one random bit. In the course of each measurement, a solid-state...
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The event was precipitated by yours truly gathering a quantum-mechanically random number between 1 and 10,000. Generating this number required making at least 15 quantum measurements, each yielding one random bit. In the course of each measurement, a solid-state...
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Have you ever been under global anesthesia? If so, when you came to, how did you know you were still you? You probably asked yourself questions like "where am I?" and the answers came back to you, from memory, as an internal dialogue. This, our memory and internal dialogue, is how we perceive our "self." If we were to make perfect copies, classical or quantum, and these selves were to ask themselves, "am I me?" the answer would come back: "yes, of course!" to both copies. It doesn't matter that there was an interruption in the stream of consciousness, any more than it mattered that your stream of consciousness was interrupted by anesthesia -- you still came back as you, and you know it because of how your memories and internal dialogue proceeded from that point forward.
If the duplication was done, and one of the copies was killed without ever being returned to consciousness, the other copy would never be the wiser -- you'd just think you were put under then brought back.
We're just not used to our classical worldline branching, so it seems bloody weird to think about.
And, umm, at one point there was another possible me very happy to receive a minigrant for a new snowboard, but I'll never get to ride it since I never applied.
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If the duplication was done, and one of the copies was killed without ever being returned to consciousness, the other copy would never be the wiser -- you'd just think you were put under then brought back.
We're just not used to our classical worldline branching, so it seems bloody weird to think about.
And, umm, at one point there was another possible me very happy to receive a minigrant for a new snowboard, but I'll never get to ride it since I never applied.
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Garrett,
I agree that it's perfectly clear that both 'Anthony's will think they are 'me'. The question is: imagine the machine is sitting there in front of you. Knowing that the next moment there will be exactly two 'Garret's, one of which is suffering an agonizing death, would you step in or not?
If yes, how do you explain your decision to the really angry (and horribly dying) Garrett?
If not, how could you believe in the Many Worlds Interpretation? (To make this more poignant, you could get up a quantum-gun that, when you pull the trigger, fires with P=0.00000000001, and aim it at your foot. Most people after seeing this gun go 'click' a many, many times would be willing to 'shoot' it at their foot for, say $50. But if you believe MWI, but would *not* step in the described machine, I think you'd be crazy to do this).
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I agree that it's perfectly clear that both 'Anthony's will think they are 'me'. The question is: imagine the machine is sitting there in front of you. Knowing that the next moment there will be exactly two 'Garret's, one of which is suffering an agonizing death, would you step in or not?
If yes, how do you explain your decision to the really angry (and horribly dying) Garrett?
If not, how could you believe in the Many Worlds Interpretation? (To make this more poignant, you could get up a quantum-gun that, when you pull the trigger, fires with P=0.00000000001, and aim it at your foot. Most people after seeing this gun go 'click' a many, many times would be willing to 'shoot' it at their foot for, say $50. But if you believe MWI, but would *not* step in the described machine, I think you'd be crazy to do this).
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Anthony:
I believe that you're focusing in too much on this hypothetical example. First, to answer your question, I would not step into the machine because it is designed to produce a copy that would be tortured for certain. The only thing that you've said is that there is a 99.999999%% chance that it won't be you. That means that there is an equal chance that it will be the "copy" that is harmed. I prefer we remove this scenario to the real world.
First, I believe in the many-worlds interpretation and have done so since 1991 for reasons that I won't go into here. Being a believer, and someone who has taken many risks between those days and now, I would view the outcomes of those risks as a distribution pattern of probabilities, hopefully with failure that would be fatal, at the extreme low end of the distribution. But that is how life works. The key is to avoid taking chances that have a high probability of catastrophic results, because you don't know where you will be along that probability distribution.
The dial, on the machine that you described, is of course the key to the whole situation - the control of probability so that the outcome that we wish to observe is the one with the highest probability that will be observed by us. Of course, another description for such a process would be engineering reality.
I think that it would be impractical to constantly think in terms of the fate of our copies, based on every decision that we make. Besides the fact that oft times our copies may suffer because of things beyond our control, for which we might not be adversely effected, sometimes, we are that copy that gets the bad end of the stick, the raw deal, what have you. It is then that we experience that sense of regret, that "what if", that "if I had only..."
The many-worlds interpretation is an amazing theory, one which I am glad has gained acceptance over the years. Perhaps I will discuss it more later, as the opportunity presents itself.
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I believe that you're focusing in too much on this hypothetical example. First, to answer your question, I would not step into the machine because it is designed to produce a copy that would be tortured for certain. The only thing that you've said is that there is a 99.999999%% chance that it won't be you. That means that there is an equal chance that it will be the "copy" that is harmed. I prefer we remove this scenario to the real world.
First, I believe in the many-worlds interpretation and have done so since 1991 for reasons that I won't go into here. Being a believer, and someone who has taken many risks between those days and now, I would view the outcomes of those risks as a distribution pattern of probabilities, hopefully with failure that would be fatal, at the extreme low end of the distribution. But that is how life works. The key is to avoid taking chances that have a high probability of catastrophic results, because you don't know where you will be along that probability distribution.
The dial, on the machine that you described, is of course the key to the whole situation - the control of probability so that the outcome that we wish to observe is the one with the highest probability that will be observed by us. Of course, another description for such a process would be engineering reality.
I think that it would be impractical to constantly think in terms of the fate of our copies, based on every decision that we make. Besides the fact that oft times our copies may suffer because of things beyond our control, for which we might not be adversely effected, sometimes, we are that copy that gets the bad end of the stick, the raw deal, what have you. It is then that we experience that sense of regret, that "what if", that "if I had only..."
The many-worlds interpretation is an amazing theory, one which I am glad has gained acceptance over the years. Perhaps I will discuss it more later, as the opportunity presents itself.
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I would have to make a decision on the desirability of the experiences of my future selves -- even though these experiences would not be shared amongst the different copies. If one of the copies is just to be snuffed out, or never revived, it's an easy decision -- since one never experiences being dead. My worldline would have a tiny dead-end stub, but otherwise continue with a happy life,
(:-D
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$
\ x
V
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(:-)
If one of the me's was to be painfully tortured, I would have to weigh the negative value of that experience against the reward and decide. I'm a pretty happy guy, so it would have to be a big reward... here you can see a future me with a double chin (and, of course, still bald),
(:-))
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| x
$ (:-(
\ /
V
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(:-)
Even though the future copies do all exist, independently, the rational choice should still be based on a weighing of cost vs benefit -- effectively the same as when one uses likelihoods of possibilities to make a decision.
This same decision process would apply to being paid to maybe shoot myself in the foot.
There is a difference between the classical copying and quantum splitting though: In the classical copying, I'd have to take into account the guilt felt by the surviving me, who watched the other me suffer while telling him it was worth it (thus the double chin, brought on by guilt induced binges). In the quantum splitting, it's best not to worry about your other, effectively nonexistent selves -- since they can't effect you (unless you're very small) -- and just role the dice.
this post has been edited by the author since its original submission
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(:-D
|
|
$
\ x
V
|
|
(:-)
If one of the me's was to be painfully tortured, I would have to weigh the negative value of that experience against the reward and decide. I'm a pretty happy guy, so it would have to be a big reward... here you can see a future me with a double chin (and, of course, still bald),
(:-))
|
| x
$ (:-(
\ /
V
|
|
(:-)
Even though the future copies do all exist, independently, the rational choice should still be based on a weighing of cost vs benefit -- effectively the same as when one uses likelihoods of possibilities to make a decision.
This same decision process would apply to being paid to maybe shoot myself in the foot.
There is a difference between the classical copying and quantum splitting though: In the classical copying, I'd have to take into account the guilt felt by the surviving me, who watched the other me suffer while telling him it was worth it (thus the double chin, brought on by guilt induced binges). In the quantum splitting, it's best not to worry about your other, effectively nonexistent selves -- since they can't effect you (unless you're very small) -- and just role the dice.
this post has been edited by the author since its original submission
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Ah, I just thought of an amusing way to think about copying yourself:
Pretend you're an Amoeba.
Pity they're not talking... no, wait, that's probably a good thing.
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Pretend you're an Amoeba.
Pity they're not talking... no, wait, that's probably a good thing.
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Garrett,
Ahh, but do the feelings of your 'tortured' version count as much as the non-tortured one? Probably you would say yes, and this is the whole point: in MWI, we are supposed to make decisions (such as whether to do a measurement that could, with tiny probability, cause our painful death) on the basis of the quantum probabilities. But tell that to the copy who is asphyxiating. :-o
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Ahh, but do the feelings of your 'tortured' version count as much as the non-tortured one? Probably you would say yes, and this is the whole point: in MWI, we are supposed to make decisions (such as whether to do a measurement that could, with tiny probability, cause our painful death) on the basis of the quantum probabilities. But tell that to the copy who is asphyxiating. :-o
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(btw, it was another me who made the amoeba comment)
Yes, the tortured version counts as much, but should be weighted by its probability. Drowning is a terrible thing to experience (I've come close) so the motive would have to be very strong -- a girl would need to be involved (otherwise it's hard to be that crazy).
In QM, and in classical Bayesian probability, our other versions don't effect us -- so, effectively, they don't exist and we shouldn't feel guilty about them.
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Yes, the tortured version counts as much, but should be weighted by its probability. Drowning is a terrible thing to experience (I've come close) so the motive would have to be very strong -- a girl would need to be involved (otherwise it's hard to be that crazy).
In QM, and in classical Bayesian probability, our other versions don't effect us -- so, effectively, they don't exist and we shouldn't feel guilty about them.
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Garrett,
Sorry, the question was in the context of the teleporter machine, or MWI, in which both copies exist for certain.
I agree that in a Copenhagenesque view, the probabilities of one thing happen versus the other matter very much.
A
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Sorry, the question was in the context of the teleporter machine, or MWI, in which both copies exist for certain.
I agree that in a Copenhagenesque view, the probabilities of one thing happen versus the other matter very much.
A
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Sure, we just have to think like amoeba's: our current self will be experiencing both outcomes, separately. There is a small difference though: In the teleporter case, we have to live with the fact that our other version died in our branch of reality; but in the MWI case our other version died in a reality separate from ours. This means our decision in the MWI case should be the same as for any classical gamble -- since the other selves effectively won't exist for each other. In the teleporter case, we'll be involved in a murder.
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(Heh, I had posted two replies. But one of them just vanished. I guess I feel OK with that.)
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"At about 1 AM GMT on April 20, 2007, the Universe split into at least 32,768 nearly-identical copies. How? And did it really?"
Well, if we are going to treat the observer not as external but internal to the multiverse and subject to the laws of quantum mechanics (leading to the copies of the same observer), then we must also describe the decisions the observer makes also using these laws.
So, it should be clear that the split into the "32,768 nearly-identical copies" was not really caused by a choice someone made that had it not been made would not have resulted in the universe splitting, because Anthony himself is part of the multiverse and there exists an Anthony who decides to have a lottery and there exists an Anthony who makes a different choice. These different Anthonies exist a priori with some amplitudes in the multiverse and nothing can "change" that fact.
So, the spittings are just artefacts of looking at special sectors of the multiverse and then comparing that sector with a another sector you obtain by applying the time evolution operator. If you apply the time evolution operator on the entire multiverse you would probably see no splittings at all because the entire multiverse could well be an exact eigenstate of the Hamiltonian.
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Well, if we are going to treat the observer not as external but internal to the multiverse and subject to the laws of quantum mechanics (leading to the copies of the same observer), then we must also describe the decisions the observer makes also using these laws.
So, it should be clear that the split into the "32,768 nearly-identical copies" was not really caused by a choice someone made that had it not been made would not have resulted in the universe splitting, because Anthony himself is part of the multiverse and there exists an Anthony who decides to have a lottery and there exists an Anthony who makes a different choice. These different Anthonies exist a priori with some amplitudes in the multiverse and nothing can "change" that fact.
So, the spittings are just artefacts of looking at special sectors of the multiverse and then comparing that sector with a another sector you obtain by applying the time evolution operator. If you apply the time evolution operator on the entire multiverse you would probably see no splittings at all because the entire multiverse could well be an exact eigenstate of the Hamiltonian.
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Garrett:
Yes, those superpositions collapsed. (or did they just decohere....)
Count Iblis:
I agree that if we assume that the universe is in a definite quantum state evolved by some fixed Hamiltonian, then there is no place for 'branching' of the cosmic wavefunction, but rather an evolution that describes one 'Anthony' and then, later, many. But as far as I (Anthony) am concerned, this certainly is a 'branching.' So whether the 'world splits' depends on how self-centered you are...
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Yes, those superpositions collapsed. (or did they just decohere....)
Count Iblis:
I agree that if we assume that the universe is in a definite quantum state evolved by some fixed Hamiltonian, then there is no place for 'branching' of the cosmic wavefunction, but rather an evolution that describes one 'Anthony' and then, later, many. But as far as I (Anthony) am concerned, this certainly is a 'branching.' So whether the 'world splits' depends on how self-centered you are...
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I would not hesitate to enter the "transporter", even without prior knowledge of the favourable probability constraint.
I would rely on the fact and knowledge based on current "experience", I would know that I would STILL remember my/the past, wheras my copy would have a 50/50 chance of remembering the/it's future!
I would retain a "current" past history, I am,thefore I am?
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I would rely on the fact and knowledge based on current "experience", I would know that I would STILL remember my/the past, wheras my copy would have a 50/50 chance of remembering the/it's future!
I would retain a "current" past history, I am,thefore I am?
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I would not hesitate to enter the "transporter", even without prior knowledge of the favourable probability constraint.
I would rely on the fact and knowledge based on current "experience", I would know that I would STILL remember my/the past, wheras my copy would have a 50/50 chance of remembering the/it's future!
I would retain a "current" past history, I am,thefore I am?
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I would rely on the fact and knowledge based on current "experience", I would know that I would STILL remember my/the past, wheras my copy would have a 50/50 chance of remembering the/it's future!
I would retain a "current" past history, I am,thefore I am?
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WOW! either I hit the hidden variable "re-copy" button, or the transporter "me" is falsifying my previous post!
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There is another constraint, which may be intepreted thus, I have a proven history, before copies were made and placed into the transporter. The "copies" history are dependant upon the transporter, they have no history prior to their creation?
Each destination has to be contained within the copies "known" historical existence, there was no point of existence prior to their creation?..so each prefered path (destiny route), is pre-chosen, and both are in a virtual future.
I would not experience any of the "destiny" outcomes, the fact is that the Transporter acts as a cut-off point for both copies that enter?
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Each destination has to be contained within the copies "known" historical existence, there was no point of existence prior to their creation?..so each prefered path (destiny route), is pre-chosen, and both are in a virtual future.
I would not experience any of the "destiny" outcomes, the fact is that the Transporter acts as a cut-off point for both copies that enter?
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