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Quantum Suicide

science.howstuffworks.com

1–10 of 18 posts

Re: Quantum Suicide

#2
They have no clue what they are talking about. For example this:

This is the same case with quantum suicide. When the man pulls the trigger, there are two possible outcomes: the gun either fires or it doesn't. In this case, the man either lives or he dies. Each time the trigger is pulled, the universe splits to accommodate each possible outcome

Universes do not split like that. That would mean many universes were being created from nothing every instant. What actually happens is there are already infinitely many "universes" and they become different. And not one per outcome, but in proportion to the probability of outcomes.

Re: Quantum Suicide

#3
haha quantum physics may as well be chinese to me. the only explanation that has ever made the least bit of sense is that cartoon with the old man super hero talking about light particles.

Re: Quantum Suicide

#4
Nice movie plot for Jet Li perhaps, but they don't actually explain how to kill yourself in all universes. So, unless you're a cat or Solid Snake, you can get out of that box now.

Re: Quantum Suicide

#5
post #2

They have no clue what they are talking about. For example this: This is the same case with quantum suicide. When the man pulls the trigger, there are two possible outcomes: the gun either fires or it doesn't. In this case, the man either lives or he dies. Each time the trigger is pulled, the universe splits to accommodate each possible outcome Universes do not split like that. That would mean many universes were bei…

>Universes do not split like that. That would mean many universes were being created from nothing every instant. What actually happens is there are already infinitely many "universes" and they become different. And not one per outcome, but in proportion to the probability of outcomes.

It's not the writers of the article who have no clue. It's quantum physicists themselves.

In the Copenhagen interpretation of QM, a conscious observer induces wave collapse (a random process). In this interpretation, there are no other worlds. In Wave Collapse/Many Worlds, a parallel universe is created in which wave collapse occured but gave a different outcome.

There are different interpretations of QM (e.g. bohmian mechanics or GRW/stochastic collapse) which don't have this problem. If you are interested in QM, I strongly suggest looking these theories up. But Copenhagen QM (the theory in most textbooks) does have this problem.

The reporter did an adequate job of explaining the consensus view. The problem is really that the consensus view can allow for nonsense such as what was described in the article.

Re: Quantum Suicide

#6
post #2

They have no clue what they are talking about. For example this: This is the same case with quantum suicide. When the man pulls the trigger, there are two possible outcomes: the gun either fires or it doesn't. In this case, the man either lives or he dies. Each time the trigger is pulled, the universe splits to accommodate each possible outcome Universes do not split like that. That would mean many universes were bei…

>Universes do not split like that. That would mean many universes were being created from nothing every instant. What actually happens is there are already infinitely many "universes" and they become different. And not one per outcome, but in proportion to the probability of outcomes. It's not the writers of the article who have no clue. It's quantum physicists themselves. In the Copenhagen interpretation of QM, a co…

In Wave Collapse/Many Worlds, a parallel universe is created in which wave collapse occured but gave a different outcome.

That is incorrect. Many Worlds does not say universes are created all the time, it says they already exist and become differentiated.

BTW all the other interpretations are ridiculous attempts to avoid facing counter-intuitive facts. See, for example, David Deutsch's speech at the recent Everett conference http://www.philosophy.ox.ac.uk/misc/everett/Deutsch%20-%20Ap...

Re: Quantum Suicide

#7
post #6

Earlier quoted context omitted.

>Universes do not split like that. That would mean many universes were being created from nothing every instant. What actually happens is there are already infinitely many "universes" and they become different. And not one per outcome, but in proportion to the probability of outcomes. It's not the writers of the article who have no clue. It's quantum physicists themselves. In the Copenhagen interpretation of QM, a co…

In Wave Collapse/Many Worlds, a parallel universe is created in which wave collapse occured but gave a different outcome. That is incorrect. Many Worlds does not say universes are created all the time, it says they already exist and become differentiated. BTW all the other interpretations are ridiculous attempts to avoid facing counter-intuitive facts. See, for example, David Deutsch's speech at the recent Everett co…

That is incorrect. Many Worlds does not say universes are created all the time, it says they already exist and become differentiated.

Actually there's no real consensus on that point, even among many-worlds theorists. Some folks suggest that universes "split", others suggest that they "become differentiated", and a third set of folks say that they do something which isn't really properly described by either of the above options. Deutsch has one of the more widely publicised many-worlds interpretations, but it's not the only one out there, and it's not necessarily the most widely accepted.

Re: Quantum Suicide

#8
post #7
post #6

Earlier quoted context omitted.

In Wave Collapse/Many Worlds, a parallel universe is created in which wave collapse occured but gave a different outcome. That is incorrect. Many Worlds does not say universes are created all the time, it says they already exist and become differentiated. BTW all the other interpretations are ridiculous attempts to avoid facing counter-intuitive facts. See, for example, David Deutsch's speech at the recent Everett co…

That is incorrect. Many Worlds does not say universes are created all the time, it says they already exist and become differentiated. Actually there's no real consensus on that point, even among many-worlds theorists. Some folks suggest that universes "split", others suggest that they "become differentiated", and a third set of folks say that they do something which isn't really properly described by either of the ab…

I don't really care what views are popular, (though MWI is popular among top experts to whom it matters), I care which views are true. So what matters to me is which proponents say things that make sense and give good explanations and arguments. Deutsch does, including a powerful and concise argument in chapter 2 of his book. When someone gives a reasonable counter argument then I will reconsider, but that has not happened.

And, of course, Deutsch isn't the only example of the MWI side making more sense. Here is another source:

http://www.hedweb.com/manworld.htm

Edit: If you can give a non-ridiculous summary of any other interpretation, go ahead...

Re: Quantum Suicide

#9
post #8
post #7

Earlier quoted context omitted.

That is incorrect. Many Worlds does not say universes are created all the time, it says they already exist and become differentiated. Actually there's no real consensus on that point, even among many-worlds theorists. Some folks suggest that universes "split", others suggest that they "become differentiated", and a third set of folks say that they do something which isn't really properly described by either of the ab…

I don't really care what views are popular, (though MWI is popular among top experts to whom it matters), I care which views are true. So what matters to me is which proponents say things that make sense and give good explanations and arguments. Deutsch does, including a powerful and concise argument in chapter 2 of his book. When someone gives a reasonable counter argument then I will reconsider, but that has not ha…

Some of the many worlds variants make sense. I prefer bohmian mechanics (I can reason about it better), but I have no objection to MW. Ultimately I don't care one way or the other: the predictions for MY universe are the same, whether or not it is unique or one amoung many.

However, the point I was making is that most physicists believe in wave collapse. The writer of the article was simply providing a reasonably good summary of QM with wave collapse. According to Q1 of your article, this is still a mainstream belief except amoung string theorists, apparently. I agree, it's almost certainly wrong. But that's not yet a mainstream position.

As for other non-ridiculous interpretations, just look at bohmian mechanics or GRW. Bohmian mechanics postulates that particles exist and are guided by the wave function. The testable physical predictions are identical to many worlds. GRW makes different physical predictions (possibly testable in the near future), but the theory makes sense as well.

Re: Quantum Suicide

#10
Does the Copenhagen Interpretation strike anyone else as eerily like lazy evaluation?

My other thought is that once you're doing 'thought experiments', you've become rather unmoored from science as I understand it: Observation, Hypothesis, Prediction, Experiment, and so forth. Hopefully, the 'thought experiments' will lead to something testable.

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