Explaining the Quantum Mystery: Are Parallel Universes the Answer?

[qspeechc]

Parallel universes exist - study

Sep 23 11:33 PM US/Eastern

http://www.breitbart.com/article.php?id=paUniverse_sun14_parallel_universes&show_article=1&cat=0

Parallel universes really do exist, according to a mathematical discovery by Oxford scientists described by one expert as "one of the most important developments in the history of science".

The parallel universe theory, first proposed in 1950 by the US physicist Hugh Everett, helps explain mysteries of quantum mechanics that have baffled scientists for decades, it is claimed.

In Everett's "many worlds" universe, every time a new physical possibility is explored, the universe splits. Given a number of possible alternative outcomes, each one is played out - in its own universe.

A motorist who has a near miss, for instance, might feel relieved at his lucky escape. But in a parallel universe, another version of the same driver will have been killed. Yet another universe will see the motorist recover after treatment in hospital. The number of alternative scenarios is endless.

It is a bizarre idea which has been dismissed as fanciful by many experts. But the new research from Oxford shows that it offers a mathematical answer to quantum conundrums that cannot be dismissed lightly - and suggests that Dr Everett, who was a Phd student at Princeton University when he came up with the theory, was on the right track.

<snip>

The Oxford team, led by Dr David Deutsch, showed mathematically that the bush-like branching structure created by the universe splitting into parallel versions of itself can explain the probabilistic nature of quantum outcomes.

I am no physicist, but it sounds like this is pretty big. From the last paragraph, it sounds like a hypothesis to me. Anybody like say what's this all about, in simple terms for the layman like myself

 

[Evo]

I can't find the study, and the New Scientist article requires a subscription. I'd like to read just exactly what it is they've come up with. Of course it's no secret that I :!) David Deutsch.

 

[zoobyshoe]

I can't find the study, and the New Scientist article requires a subscription. I'd like to read just exactly what it is they've come up with. Of course it's no secret that I :!) David Deutsch.

It can be demonstrated mathematically that your love for him is completely requited (but only in some obscure parallel universe).

 

[Ivan Seeking]

Of course, in another, Evo and Zooby are married and have seven children!

 

[Evo]

Of course, in another, Evo and Zooby are married and have seven children!

Well, we refer to them as children, actually they are hippos we relocated to the zooby brush shelter.

 

[Jimmy Snyder]

It can be demonstrated mathematically that your love for him is completely requited (but only in some obscure parallel universe).

I can't speak for Evo, but I expect she requires a physical demonstration.

 

[qspeechc]

:'( I thought I'd actually get intelligent comments from intelligent people; not to say you're unintelligent ofcourse!

 

[Evo]

:'( I thought I'd actually get intelligent comments from intelligent people; not to say your unintelligent ofcourse!

I've looked for the study, all I could find was the New Scientist article, but it requires a subscription.

http://www.newscientist.com/channel...00-parallel-universes-make-quantum-sense.html

It's rather hard to discuss a study without reading it.

 

[wolram]

May be every one should clap and wave their hands, how about street parties?

 

[EnumaElish]

Why is this thread under Gen. Disc., as opposed to, say, physics or math?

 

[SpaceTiger]

Ditto what Evo said, but I can say that the multiple universes idea is legit. I was under the impression, however, that there was no way to distinguish that from, say, the Copenhagen interpretation. If there is a way of distinguishing them, then obviously it's a really important result, but I'm skeptical.

 

[Ivan Seeking]

Why is this thread under Gen. Disc., as opposed to, say, physics or math?

We need to see a reference to a paper published in a peer-reviewed journal.

 

[Gokul43201]

There doesn't appear to be anythnig on the arXiv as yet, and I didn't find anything in Nature News, SciAm, Physicsworld or on Detcsh's website. If there really is something new here, I imagine vanesch would know.

 

[zoobyshoe]

Well, we refer to them as children, actually they are hippos we relocated to the zooby brush shelter.

That's not the same universe Ivan is talking about. He's talking about the one where he and Math is Hard are our #4 and #5 kids. Fraternal twins, in fact. They grow up to run a family algae tea business. This is about 14 x10^56 branches away from the universe where our kids are hippos.

 

[Doc Al]

I can't help but wonder if it's a bit of a publicity stunt, timed to coincide with the 50th anniversary of Everett's paper. An "Everett at 50" conference just concluded yesterday.

 

[Astronuc]

But isn't a parallel universe non-testable/non-falsifiable. One cannot get outside this one, so one is left with an abstract mathematical model that has no physical reality behind it - well it's real more or less if it is consistent with observable phenomenon in this universe?

Is this all about all possible outcomes of some event?

 

[Evo]

I can't help but wonder if it's a bit of a publicity stunt, timed to coincide with the 50th anniversary of Everett's paper. An "Everett at 50" conference just concluded yesterday.

Yes, I'm a bit skeptical about a news story about an article about a study. No telling what the study actually concluded.

 

[Art]

A problem with a multiverse containing all possible outcomes is one would expect to see multiple 'miracles' happening every day as our universe absorbed it's share of very unlikely outcomes. If all the really unlikely outcomes are reserved only for other universes then it would suggest some kind of intelligent controller overseeing things.

 

[Moonbear]

Yes, I'm a bit skeptical about a news story about an article about a study. No telling what the study actually concluded.

The most difficult part is that the news story isn't even clear whose work it's talking about. It refers to Everett's work, Deutsch's work, some other folks, but talks about it all so vaguely that it could be nothing more than a recap of all the old stuff (and unless Deutsch has been asleep at the wheel since 2004, he desperately needs to update his website to include more current publications!) There's no reference to the source of the original article that spurred the story, and I don't know if it would be contained in the Sci Am article either.

Even from what the vague article is saying, though, it doesn't really sound like anyone is saying there ARE parallel universes, more that it's a probability model that sets up all the different possible outcomes AS IF there were multiple universes, and until one observes what actually happens, and of those possible outcomes may be reality. But, this stuff is WAY beyond my expertise, so I could be misinterpreting that as badly as the news story about the magazine article about the scientific paper(s) may be misinterpreting it.

 

[Evo]

A problem with a multiverse containing all possible outcomes is one would expect to see multiple 'miracles' happening every day as our universe absorbed it's share of very unlikely outcomes. If all the really unlikely outcomes are reserved only for other universes then it would suggest some kind of intelligent controller overseeing things.

The outcomes don't have to be miraculous, just different.

For example last week I walked the dog and broke my arm, alternatives would be not breaking my arm, breaking my leg, spraining my arm, not falling, not walking the dog, not owning a dog, etc...

 

[Astronuc]

It seems the Breitbart article is reference the work of Deutsch et al at Oxford, and also cites a parallel (just couldn't resist) article in New Scientist, which includes a comment by Dr Andy Albrecht of UCD. All this supports the conjecture of Everett. But the 'mathematical discovery' is attributed to the Oxford group.

The Oxford team, led by Dr David Deutsch, showed mathematically that the bush-like branching structure created by the universe splitting into parallel versions of itself can explain the probabilistic nature of quantum outcomes.

I'm skeptical.

 

[Ivan Seeking]

But isn't a parallel universe non-testable/non-falsifiable. One cannot get outside this one, so one is left with an abstract mathematical model that has no physical reality behind it - well it's real more or less if it is consistent with observable phenomenon in this universe?

Is this all about all possible outcomes of some event?

How do you take the leap from "can't be measured" to "doesn't exist". Sure, it doesn't exist in our universe, but by definition we are talking about a multiverse. I think yours is one interpretation, but not the only one.

Vanesch could help here.

 

[Astronuc]

Maybe I should have said that outside this universe is 'unrealizable' and as such, one can only 'speculate' as one would do about an 'afterlife', which anyone could start to argue is simply a parallel universe.

Would those models also speculate that the same 'laws' exist, e.g. spin, mass, matter, e/m, quark charge, color, m_e/m_p, . . . . are the same or different?

 

[Art]

The outcomes don't have to be miraculous, just different.

For example last week I walked the dog and broke my arm, alternatives would be not breaking my arm, breaking my leg, spraining my arm, not falling, not walking the dog, not owning a dog, etc...

But some of the most unlikely outcomes (from our perspective) would appear miraculous. If all possible outcomes actually happen then it follows that highly unlikely results should be as common as expected results as the highly unusual should be mixed equally with the usual. For example there tends to be very few survivors from a plane crash. Surviving is a possibility so in the multiverse, assuming each universe is of equal merit, there must be a branch of reality where all the passengers survive and this possibility should have equal weight to none surviving yet we never see the result where all the passengers survive and so it seems (again based on our expectations) all of the highly unlikely outcomes end up in someone else's universe. So why not in ours?

 

[Evo]

But some of the most unlikely outcomes (from our perspective) would appear miraculous. If all possible outcomes actually happen then it follows that highly unlikely results should be as common as expected results as the highly unusual should be mixed equally with the usual. For example there tends to be very few survivors from a plane crash. Surviving is a possibility so in the multiverse, assuming each universe is of equal merit, there must be a branch of reality where all the passengers survive and this possibility should have equal weight to none surviving yet we never see the result where all the passengers survive and so it seems (again based on our expectations) all of the highly unlikely outcomes end up in someone else's universe. So why not in ours?

Perhaps it is only alternative outcomes that don't defy known laws. If a plane crashes, tears apart and burns, we know the human body can only survive so much. For all passengers on a destroyed plane to survive would not be natural. If I drop a rock on my toe in this universe, an alternative would not be for the rock to fly upwards, or turn into a feather.

In an alternate universe, I wouldn't give birth to a chicken. I think it is alternate realistic scenarios.

But what do I know?

 

[Art]

Perhaps it is only alternative outcomes that don't defy known laws. If a plane crashes, tears apart and burns, we know the human body can only survive so much. For all passengers on a destroyed plane to survive would not be natural. If I drop a rock on my toe in this universe, an alternative would not be for the rock to fly upwards, or turn into a feather.

In an alternate universe, I wouldn't give birth to a chicken. I think it is alternate realistic scenarios.

But what do I know?

People do survive aircrashes so it is not breaking the laws of nature but it is interesting to see you mention realistic outcomes which brings me back to my point who decides we get all of the realistic outcomes and somebody else ends up with all of the 'unrealistic' outcomes. In a multiverse where each universe is of equal merit realistic and unrealistic outcomes should have equal weighting.

For example if an event has 4 possible outcomes where;

a) Is highly likely
b) Is moderately likely
c) Is moderatly unlikley
d) Is highly unlikely

So the universe splits in 4 to accommodate each outcome why is it our universe gets nearly all a's. Random chance would dictate that we would see an equal share of all 4. Who decides that c and d are nearly all pushed off on a different branch into another alternate universe?

 

[Evo]

People do survive aircrashes so it is not breaking the laws of nature but it is interesting to see you mention realistic outcomes which brings me back to my point who decides we get all of the realistic outcomes and somebody else ends up with all of the 'unrealistic' outcomes. In a multiverse where each universe is of equal merit realistic and unrealistic outcomes should have equal weighting.

But we do have "unrealistic" or "miraculous" outcomes to events every day, they just don't defy the laws of nature. What about skydivers that survived their parachutes not opening? What about those people with huge nails in their heads?

 

[Art]

But we do have "unrealistic" or "miraculous" outcomes to events every day, they just don't defy the laws of nature. What about people skydivers that survived their parachutes not opening? What about those people with huge nails in their heads?

You probably wrote this before I posted my edit Evo but I think I answered your points in that.

 

[SpaceTiger]

But some of the most unlikely outcomes (from our perspective) would appear miraculous. If all possible outcomes actually happen then it follows that highly unlikely results should be as common as expected results as the highly unusual should be mixed equally with the usual. For example there tends to be very few survivors from a plane crash. Surviving is a possibility so in the multiverse, assuming each universe is of equal merit, there must be a branch of reality where all the passengers survive and this possibility should have equal weight to none surviving yet we never see the result where all the passengers survive and so it seems (again based on our expectations) all of the highly unlikely outcomes end up in someone else's universe. So why not in ours?

This is sort of like asking, "Why don't improbable things happen?"

The answer is that they do happen, just not very often. They're improbable. The concepts behind probability are not in any way altered by the many worlds hypothesis.

 

[Art]

This is sort of like asking, "Why don't improbable things happen?"

The answer is that they do happen, just not very often. They're improbable. The concepts behind probability are not in any way altered by the many worlds hypothesis.

As I pointed out in post 26 once the universe splits to allow different outcomes if every universe has equal merit then the improbable should happen as commonly as the probable.

 

[Jimmy Snyder]

So if there are two possible outcomes and they have an equal probability of occurring then the universe bifurcates into one each for both of the outcomes. But what if the probability is not equal, then what? What about continuous ranges of possible outcomes where the probability of anyone of them is zero? Is this what the mathematicians have worked out?

 

[SpaceTiger]

As I pointed out in post 26 once the universe splits to allow different outcomes if every universe has equal merit then the improbable should happen as commonly as the probable.

Again, many worlds doesn't change the laws of probability. The statement "every universe has equal merit" is not true if it means that every possible outcome has equal probability. It is true (in this context) if it means that we are equally likely to live in any of the universes.

If an outcome has a 10% probability, then it occurs in 10% of the universes and we have a 10% chance of living in a universe with that outcome.

 

[Art]

Again, many worlds doesn't change the laws of probability. The statement "every universe has equal merit" is not true if it means that every possible outcome has equal probability. It is true (in this context) if it means that we are equally likely to live in any of the universes.

If an outcome has a 10% probability, then it occurs in 10% of the universes and we have a 10% chance of living in a universe with that outcome.

How do you tie this into the example I gave where the universe splits in 4 to accommodate 4 possible outcomes. Are you saying it creates 95 versions of option a to 1 version of option d to maintain probabilities? The version of the multiverse theory I've heard is simply that the universe splits to accommodate all possible outcomes but once it splits one would expect all branches to be equally valid.

 

[SpaceTiger]

How do you tie this into the example I gave where the universe splits in 4 to accommodate 4 possible outcomes. Are you saying it creates 95 versions of option a to 1 version of option d to maintain probabilities?

We have to be careful in understanding where the uncertainty is coming from. If the uncertainty is quantum in origin, then yes. If the uncertainty arises from incomplete knowledge of the system, then
quantum theory is effectively irrelevant and we won't actually know how many of the universes carry a particular outcome. The latter will always be the case in everyday probabilities.

 

[EnumaElish]

How do you tie this into the example I gave where the universe splits in 4 to accommodate 4 possible outcomes. Are you saying it creates 95 versions of option a to 1 version of option d to maintain probabilities? The version of the multiverse theory I've heard is simply that the universe splits to accommodate all possible outcomes but once it splits one would expect all branches to be equally valid.

Art, technically what you are saying is outcomes are distributed uniformly across universes. An alternative would be they are distributed normally across universes with a probability mass centered around the "mean outcome" that thins out as one gets farther from the mean. Space Tiger's explanation favors a normal distribution over a uniform distribution.

[BTW, since you are a contributor, you should be entitled to have an avatar.]