Quantum Suicide, or: The Hypocrisy Thereof

or: How I Stopped Worrying And Learned To Love The Cat:*

So, I just found out the basics of the Quantum Suicide/Many Worlds Interpretation Theory. Frankly, I think it's bullshit.

If anyone doesn't know the story, basically imagine this: there's a man (named Dave) tied to a chair, staring down the barrel of a gun ten feet away. But this is no ordinary gun; it is hooked up to a crazy new-fangled machine that can measure the spin of a quark (either up or down. There's others, but they don't occur in nature or something), and if it's spinning up, then the gun goes off. Otherwise, it doesn't fire. This means that every time the trigger of the gun is pulled, there is precisely 50% chance that Dave will die. However, it doesn't matter how many times Dave presses the gun, he will only be aware of surviving. This is because every time the computer measures the quark, the universe splits into two exact copies, one in which Dave dies, and another in which he doesn't. When he dies, he's obviously not aware of that, because he's dead, and since we're all scientists here we're assuming atheism. So he can keep pulling that trigger all day long with no fear, or that's the theory, anyway.

Thing is, I think it's incredibly hypocritical that these Quantum Physics guys can attack religious people all the time for making unverifiable theories just because they're convenient excuses for their ideas, when the physicists are doing the same thing! There is no way to find out if there is a multi-verse or not, and the only reason people think there might be is because it would be a convenient explanation for why photons can be particles one moment and waves the next, or both at the same time!

Just saying. This has bugged me for the whole few hours since I first understood the Quantum Suicide idea. So is there a reasonable explanation that I've missed, because, to be fair, I know next to nothing about quantum physics, and if so, care to enlighten me?

*

Um... isn't this just the cat thing? But... with a different set up?

It's important to understand that the many worlds hypothesis is just that, a hypothesis. Nobody's saying it has to be true (and I think the majority of scientists now say it's probably false.)

Edit: Also, quantum suicide isn't a support for the many worlds hypothesis, but a product of it. If many worlds is false (which, again, it probably is), there's no quantum suicide.

edited 31st Oct '11 3:50:05 PM by feotakahari

Err what, exactly, is the problem here?

Quantum suicide, just like the cat, is an entertaining thought experiment. The fact that it is unreasonable is kind of the point.

Although, I like the Quantum Bogosort better — it's an ordering algorithm with a time complexity of O(n) which works like this:

1. Order the list randomly, using true quantum randomness.
2. Check the list. If it is not in the correct order, destroy the universe.

According the many world interpretation, and using the same argument that the OP mentioned, it follows that this algorithm will always return the correct list, and faster than any other algorithm. And really, why worry about the destruction of uncountably many universes if that allows you to shave your average case performance from O(n lg n) to O(n)?

@OP: You're right that multiple Universes are impossible to observe, but probably in a different sense than you think.

One working definition of Universe is "everything that exists and therefore interacts with everything else." This includes Space and Time as well as everything in them.

If there were other universes in the traditional sense offered by the Multiverse hypothesis, they would indeed be outside of our capacity to observe them. But some have suggested that parallel (that is, similar to ours but with different types or a different number of dimentions) universes might in fact interact, albeit in less than direct ways. To elaborate, the gravity of parallel universes has been offered as an explanation of dark matter. If it was the case that this hypothesis was correct, then we would have to conclude that we are observing some effect of those parallel universes, and they would thus be part of, even if tangential to, our own Universe.

But this is somewhat irrelevant. A more important point that has to be made here - and I'm sorry to say it, too, is a semantic one - is the difference in the meanings of the word "theory" in its scientific and everyday usage.

To start with, a hypothesis, in science, is (to quote Wiktionary:)

The many-worlds, or Multiverse, "theory" (as laypeople often call it) is in fact a hypothesis.

Now, let's look at the two meanings of the word theory (I'm quoting the Oxford English Dictionary as quoted by Richard Dawkins in The Greatest Show on Earth: The Evidence for Evolution; and I'll be adding emphasis):

In the sciences, sense 1 is used; and according to the discussion in the Wiktionary article for theory, "... a fun way to make your scientist/scientifically trained friends wince is to use theory to mean “supposition” ...".

(As a side note, when someone uses the phrase "only a theory" in relation to evolution while debating it with someone with interest or education in science, it is likely that the scientifically inclined person will in fact wince, and that the other side will take it as a sign that they've made a good case, not that they've repeated a very common mistake (one of changing the paradigm of the discussion for the duration of one sentence.) )

There's nothing wrong with proposing a hypothesis to explain a phenomenon; just don't claim it's a scientific theory (as in, a hypothesis that has more evidence supporting it than any other competing hypothesis and accounts for all of the known facts that it is supposed to explain.) I've never seen the Multiverse hypothesis presented as an accepted theory in scientific writing, but I have heard people use the word "theory" in its everyday meaning (equal to "hypothesis") when discussing the Multiverse hypothesis.

edited 31st Oct '11 6:42:50 PM by BestOf

I hate to call Richard Dawkins wrong, but Richard Dawkins is wrong.

"Theory" is a term for a falsifiable explanation for an observation. It has nothing to do with how much proof it has. (And of course it can't, because science isn't in the business of declaring things "true", only "not yet false".)

A theory still remains a theory even after it's disproven. The caloric theory of heat was a perfectly good theory, which had a perfectly falsifiable definition, and turned out to be false. The aether theory of light was a good theory, perfectly falsifiable, and again turned out to be false.

Perhaps I was unclear. To quote the definition in the link you provided:

I hope I didn't imply that a theory is something that is absolutely true beyond any doubt. Instead, a theory is a word that is reserved for the hypothesis which has the highest prestige among the hypotheses that compete to explain the same (set of) phenomenon (or phenomena.)

If you read the definitions that I quoted from the (quote of the) OED, you'll find that it only says that it is generally accepted in science to be a valid, proven hypothesis. I'll emphasise different parts of the text I chose to emphasise in my previous post:

You'll never find Richard Dawkins (or me) stating that anything in science is beyond any form of doubt; but you'll find him (and me) stating that some theories are supported by such overwhelming amounts of evidence that they are beyond reasonable doubt under the view of the universe that we have now. No one's saying that evolution is unfalsifiable; on the contrary, there are very many ways in which evolution could be falsified, such as the discovery of "a rabbit fossil in the Precambrian," to quote Haldane.

Again, there's a distinction between the common usage of the word "theory" and its scientific use. In both senses, it is falsifiable, so you're obviously right about that. The distinction is laid out in the first link in your post.

It appears that once-accepted theories are (at least at times) still called theories. That obviously is a linguistic (or rather, lexical) vestige of the time when "theory" was the appropriate term for it. If Einstein's theory of general relativity was ever disproven, it should technically be referred to as "Einstein's hypothesis of general relativity," but that does not seem to happen.

Of course, the mere fact that "theory" has two related but distinct meanings is enough to account for the overlap in their use.

edited 31st Oct '11 9:12:28 PM by BestOf

(decided to edit out)

edited 1st Nov '11 12:11:15 AM by jasonwill2

Ah, Richard Dawkins. I can't decide whether to say "you're not on my side," "Stop Helping Me," "Dude, Not Funny!," "Dude, so funny," or "all of the above."

Oh well.

This is probably the best explanation of quantum physics and the cat and all that I've ever seen. The whole channel is pretty beast, though they don't have a lot of videos... sadly...

I only quoted Dawkins' book because I don't have access to the OED (I suspect, though, that I could log in there through the University in which I study, but I would have to ask someone how to do it.) If someone's wrong, it's the Oxford University Press* (or, more likely, me, as I might've misstated something, though I can't find from my post anything that could easily have been misread.)

*The definitions (the things I had in quoteblock, including "sense 1" and "sense 2") are direct quotes from the OED, not something that Dawkins wrote after reading it.*

Let's not turn this into a derail about Dawkins.

edited 31st Oct '11 9:10:28 PM by BestOf

the video forgets one important part: this does not work for cats, only sub-atomic particles such as an electron.

=0=0=0=0=0=0=

why does everyone that this analogy actually applies to our daily life? It ONLY applies to sub atomic particles.

again, the uncertainty principle only applies to sub-atomic particles.

also as someone mentioned if Dark matter is gravity sinking in from other Universes, then we could indirectly prove their existance, I have some old news I kept on my machine from when I read a couple of times that we directly observed Dark matter interact in unusual ways with normal matter.

edited 31st Oct '11 9:21:12 PM by jasonwill2

Hey, it's a video simple enough for me to grasp. Obviously, it isn't really how the actual theory goes, silly.

well i wasnt getting on you, but that important bit everyone seems to forget so then some laymen go "thats stupid!" because the physicists forgot to mention it doesn't actually work with cats and only particles of matter.

edit: though I am more likely to support the Copenhagen Interpretation than the many worlds view for a few reasons, it's not as if the many worlds view is the only one, but it's the one that gets the most attention. Roger Penrose actually supports the Copenhagen Interpretation, I have his book "The Road to Reality" now that I think about it...

edited 31st Oct '11 9:29:06 PM by jasonwill2

The Multiverse hypothesis is currently being tested in various institutions around the world, but currently it has no significant standing evidence to my knowledge.

We already know that dark matter has gravity; that is pretty much the only thing we do know about it. It is possible to locate it by observing the effect its gravity has on the movement of galaxies and comparing the actual data with virtual models that don't include the gravitational effect of dark matter. (Note that I'm no expert and could be wrong here.)

In case there's someone who doesn't know any of the other models that have been proposed to account for the conflicts between Quantum mechanics and General Relativity, the most prominent ones (again, to my knowledge) are string theory (and its offspring, M-theory) and loop quantum gravity.

edited 31st Oct '11 9:38:02 PM by BestOf

But I like multiverse theory. It seems rather more logical, to me.

I think you meant to say the movement of stars on the outskirts of galaxies, otherwise your fine. As far as I know it isn't directly effecting Galaxy's movement.

Dark Matter exists in a halo around many Galaxies, it was first termed and hypothesized to account for higher than normal orbital speeds around the Galactic Core than would be expected with Newtonian models.

Have you heard teh Copenhagen interpretation though yet?

edit:

from Wikipedia, apparently it is the more popular one.

edited 31st Oct '11 9:35:50 PM by jasonwill2

My knowledge of quantum physics is very, very shallow, unfortunately...

It's way past the theoretical absolute mind fuckery value of science and math combined, and defies all rational thought from a future liberal arts major.

I also meant to include the distortion of the light that is emitted by distant galaxies caused by dark matter.

and that, combined with experimental confrimation of Quantum Mechanics by how accurate it's predictions are, is why it is so awesome.

edit: I should ammend what i said about belief in god earlier.

I feel stupid, but in all fairness I more often hear about evolutionary biologists like Richard Dawkins ripping on religon way more than you hear someone like Hawking who says "god doesn't just play dice, he also hides the dice".

you can see why I might of assumed that in my first post >.>

edited 31st Oct '11 9:44:57 PM by jasonwill2

From my understanding, quantum mechanics is inherently probabilistic; you can't determine the exact results, but instead you get possibilities. The question is how you interpret the results. Copenhagen Interpretation states that a collection of waves collapses into one result when you superimpose enough of them and observe. Many-worlds just assumes that all of the results are real.

That's the thing. They're different hypotheses; they're different philosophies. It depends on what metaphysical assumptions you make. IMO, failing to realize that this is very much philosophical in nature is what causes problems. Science is rooted in philosophical base, and one shouldn't forget it.

I agree on the last sentence of your post, but I know of no reason why the controversy between the different solutions to unifying quantum mechanics and general relativity couldn't be solved scientifically. It could very well be that the many-worlds interpretation is at some point in the future conclusively disproved or that it is validated; the same, of course, applies to string theory and loop quantum gravity.

As for the most often cited examples of religious physicists, some confusion is caused by quote mining. For example, Hawking isn't religious; instead, he uses "God" as a rethorical short-hand for "the Universe and the laws that govern it."

To quote Wikipedia's article on Hawking (section "Religious Views":)

Einstein used "God" in a similar way, though with a hint of added mysticism; and he repeatedly said as much. Wikipedia's article on Einstein's religious views includes the following quotes:

And, most tellingly, in a response to a letter inquiring about the validity of claims repeated in American press of Einstein being traditionally religious,

He didn't consider himself an atheist, either; his beliefs have been described as panentheistic. (Note: panentheistism is not the same as pantheism.)

Of course, this post isn't directly related to quantum suicide, but it is still related to the some of the last points made in the OP.

As a final, slightly more off-topic aside (to which I don't expect replies, as I'll just be stating something ridiculously obvious,) Einstein may have been generalising with too broad strokes when he claimed that outspoken atheists (which is what I read "professional atheist" as) derive their "fervour" from religious indoctrination, as there have been vocal atheists without a religious background long before Einstein's time.

I was never raised into a religion (though my teachers in school made no effort to draw a distinction between the fictional portions (such as the flood) of the Bible and the history of religion.) Most of the atheists I know (which is to say, most of the people I know) were never really religious, even though they did attend mandatory church services in school (the only way to get around those was to have a note from your parents, which was more trouble than most kids were willing to bother for, even though their parents probably would've written up a note without a second thought.)

As for Dawkins, who is often (for reasons that I really don't understand) cited as a very offensive and unpolitely outspoken atheist, he never received a religious upbringing, either; his parents weren't religious, and he only learned religion in school (though back then, there was a whole lot more of it than there is now.) He did believe in God for a while in his teens, when he was overwhelmed by the illusion of design in nature and the watchmaker analogy; but when he read about evolution and finally got it, he lost his faith.

(The reason I keep mentioning Dawkins is that there are certain arguments and comments that tend to get thrown around a lot on these discussions, so when I see a bridge from something I post to one of those comments, I anticipate it by including an answer to it in the original post - or, as I'm doing now, in an edit.)

edited 1st Nov '11 12:20:43 AM by BestOf

Oh, well thats interesting. Also im pantheistic so I am aware of the difference.

I was just saying that some Physicists were Deists (or similar things) and not out right atheists is all.

Obviously, a great many physicists are something else than atheists. Deism is a particularily common form of religion among physicists.

(Note that I added things to my previous post.)