Do Parallel Universes really exist? Read article.

[coloradodem2005]

The same but different

For years parallel universes were a staple of the Twilight Zone. Science fiction writers loved to speculate on the possible other universes which might exist. In one, they said, Elvis Presley might still be alive or in another the British Empire might still be going strong. Serious scientists dismissed all this speculation as absurd. But now it seems the speculation wasn't absurd enough. Parallel universes really do exist and they are much stranger than even the science fiction writers dared to imagine.

Greater dimensions

It all started when superstring theory, hyperspace and dark matter made physicists realise that the three dimensions we thought described the Universe weren't enough. There are actually 11 dimensions. By the time they had finished they'd come to the conclusion that our Universe is just one bubble among an infinite number of membranous bubbles which ripple as they wobble through the eleventh dimension.

<snip>

http://www.bbc.co.uk/science/horizon/2001/paralleluni.shtml

[punpirate]

1. I think, right now, this falls into the category...

... of thought experiment. Still, it's fun to consider a parallel universe where Dubya was a garbage collector who drank too much at night, and Poppy was too poor to retire, and spent his days picking up cans on the side of the road for the deposit....

[coloradodem2005]

3. I would like to see one where Gore won in 2000.

9/11 never happened and Fox News discontinued because ratings got too low.

[indigobusiness]

6. no...it is far beyond thought experiment.

Watch the Nova on String Theory.

[punpirate]

8. Saw it several years ago (unless there's a new episode)...

... but I still don't see in that conclusive proof from empirical experiment. Lots of intriguing possibilities, but not conclusive evidence. Much of this still depends upon advanced mathematics, not empiricism. Empirical experiment may eventually prove the math, but not yet, I think.

[indigobusiness]

9. check again

[punpirate]

11. Explain... episode or...

... empirical evidence. Specificity helps.

Cheers.

[indigobusiness]

14. String theory hasn't been pinned down nor fully

explored. But, there are some interesting real world aspects of the theory that have come to light.

I would also add that empirical evidence has its place, and is an essential rigor of the scientific method, but would you deny the flight of a bumble-bee because it cannot be empirically explained?

Like Richard Feyman said about Quantum theory, "If you think you understand it, you don't".

The developments in String theory are exciting and real.


from Michio Kaku:

Cumrun Vafa at Harvard has said, “I may be biased on this one, but I think it is perhaps the most important development not only in string theory, but also in theoretical physics at least in the past two decades.” What is triggering all this excitement is the discovery of something called “M-theory,” a theory which may explain the origin of strings. In one dazzling stroke, this new M-theory has solved a series of long-standing puzzling mysteries about string theory which have dogged it from the beginning, leaving many theoretical physicists (myself included!) gasping for breath. M-theory, moreover, may even force string theory to change its name. Although many features of M-theory are still unknown, it does not seem to be a theory purely of strings. Michael Duff of Texas A & M is already giving speeches with the title “The theory formerly known as strings!” String theorists are careful to point out that this does not prove the final correctness of the theory. Not by any means. That may make years or decades more. But it marks a most significant breakthrough that is already reshaping the entire field.

Parable of the Lion
Einstein once said, “Nature shows us only the tail of the lion. But I do not doubt that the lion belongs to it even though he cannot at once reveal himself because of his enormous size.”

[Guaranteed]

17. Dude...if we can't see the lion,

we can't see the lion. So why do we keep trying to see the lion?

No comprendemos!

[punpirate]

22. Well, maybe I'm an old-fashioned guy...

... but empirical proofs are somehow satisfying. When Einstein said gravity influenced light, the mathematical proof was elegant, but some did not believe, until there was empirical proof, which came about decades later. Still, I think that's the central point of The Dancing Wu Li Masters, that physics has become much more the realm of mathematicians, than empiricists, and emotionally, those two groups do live in different dimensions.

As I said, though, I still think it's fair to describe it as a thought experiment (at least in the context of its aim--to describe a unifying theory)--even Edward Witten has said that he doesn't yet have the mathematics to resolve the approximations in fitting the five strings to a 10-dimension model, and that aggregate to the 11-dimensional supergravity model. When the mathematics becomes precise, there will be a great many more empiricists who will see its value. Designing an experiment to verify the presence of a graviton or a gravitino, especially if it occupies space in another set of dimensions, will not be easy, but possible with good proofs.

Cheers.

[indigobusiness]

25. Reality is what it is...

with or without proof.


You don't find God by measuring a church.

[indigobusiness]

26. Your point is well taken

and your references splendid.

My point was just to sress that a philosophical perspective to scientific mystery often yields the deepest insight.

Worked well for Einstein.

[indigobusiness]

16. furthermore

Detractors of String Theories
To the critics, however, these mathematical developments still don't answer the nagging question: how do you test it? Since string theory is really a theory of Creation, when all its beautiful symmetries were in their full glory, the only way to test it, the critics wail, is to re-create the Big Bang itself, which is impossible. Nobel Laureate Sheldon Glashow likes to ridicule superstring theory by comparing it with former Pres. Reagan's Star Wars plan, i.e. they are both untestable, soak up resources, and both siphon off the best scientific brains.

Actually, most string theorists think these criticisms are silly. They believe that the critics have missed the point. The key point is this: if the theory can be solved non- perturbatively using pure mathematics, then it should reduce down at low energies to a theory of ordinary protons, electrons, atoms, and molecules, for which there is ample experimental data. If we could completely solve the theory, we should be able to extract its low energy spectrum, which should match the familiar particles we see today in the Standard Model. Thus, the problem is not building atom smashers l,000 light years in diameter; the real problem is raw brain power: of only we were clever enough, we could write down M-theory, solve it, and settle everything.

Evolving Backwards
So what would it take to actually solve the theory once and for all and end all the speculation and back-biting? There are several approaches. The first is the most direct: try to derive the Standard Model of particle interactions, with its bizarre collection of quarks, gluons, electrons, neutrinos, Higgs bosons, etc. etc. etc. (I must admit that although the Standard Model is the most successful physical theory ever proposed, it is also one of the ugliest.) This might be done by curling up 6 of the 10 dimensions, leaving us with a 4 dimensional theory that might resemble the Standard Model a bit. Then try to use duality and M- theory to probe its non-perturbative region, seeing if the symmetries break in the correct fashion, giving us the correct masses of the quarks and other particles in the Standard Model. Witten's philosophy, however, is a bit different. He feels that the key to solving string theory is to understand the under- lying principle behind the theory.

[Guaranteed]

15. When physicists figure out how to reconcile

electromagnetism and gravity as far as the unified field theory goes, maybe we can continue making things up.

Until then, all this is garbage.

[indigobusiness]

18. Go flog yourself

FlatEarther.

[VoteDemocratic2004]

2. What if it's like this

When you die you go into a different dimensions and when people see ghosts they are actually seeing people from another dimension.

[opihimoimoi]

4. Stephan Hawkings describes this in A BRIEF HISTORY OF TIME

and THE UNIVERSE IN A NUTSHELL.

[agates]

30. A readable book on physics and other sciences

A Short History of Nearly Everything by Bill Bryson is another good book on the subject.

[indigobusiness]

5. Michio Kaku is the best theorstical physicist for laymen to listen

to when grappling with this stuff. He is a great teacher and a good man. I enjoy listening to him whenever I get the chance. He shows up all over the place, and makes sense of the most dificult concepts.

[moof]

10. Do you think he is better than Mike Greene ?

[indigobusiness]

12. yes

I do.

[indigobusiness]

20. And Brian Greene,

too.

[moof]

28. Drat, sorry yes, meant to say "Brian Greene"

Not sure who Mike Greene is, must be an alternate universe.

[indigobusiness]

29. I'm sure he's very smart

wherever he is.

[Fridays Child]

7. Could you all quiet down, now? I need to get some sleep.

Thanks.

[WindRavenX]

13. And what's more...

I think I read something about this in Discovery magazine (or Science mag, or whatever) that said that basically because we are "one bubble" among numerous other bubbles, for every choice where two outcomes/possibilities exist, the other possibility for that situation must exist and you can VISIT those other possible worlds. They even had an estimate of the distance one must travel (don't remember what it was, but it was, obviously, very far away :P ).
It's pretty cool stuff, and as a science freak, I love thinking about the possibility of a world where I got into Harvard instead of Boston College :evilgrin:

[Guaranteed]

19. Now, which universe are you saying that in?

Why do I live in this particular universe? Why not one of the others?

On edit: Are we all living in the same universe? Or are all of you guys just robots?

[indigobusiness]

21. Nothing is what it seems,

nor is it different.

[Lindsey]

23. "What the Bleep Do We Know" is an excellent movie out

that's in very limited release. They also have a really good website whatthebleepdoweknow that explains what the film's about. I saw it for the 2nd time Saturday night here in So. Cal.

[indigobusiness]

24. CORRECTION: "Nothing is what it seems

nor is it otherwise."

sorry

[Terran]

27. The physics are beyond my liberal arts mind...

...but as a SF buff, this stuff is literary ambrosia to me! Alternate history/parallel universe stuff is by far my favorite sub-genere of science fiction.

But I don't recall this sort of thing being the "meat and potatoes" of "The Twilight Zone," does anyone else? Sure, they did a few episodes that could be interpreted that way (the one about the woman in the hospital getting plastic surgery, who wakes to find that she is still beautiful by our standards but hideous by those of everyone in her world, comes to mind), but I don't recall any episodes the dealt explicitly with alternate reality. It was a comparatively new thing back when TZ was on.

Ward Moore's "Bring the Jubilee" is still one of best such written works, IMO.

http://www.ahtg.net/alterframe.html (a cool site)