Other Universes May Be Detectable

[Brother Jeff]

Other universes may be detectable, published study claims

 

Oct. 11, 2007

Special to World Science

 

If there are oth­er un­iverses out there—as some sci­en­tists pro­pose—then one or more of them might be de­tect­a­ble, a new study sug­gests.

 

Such a find­ing, “while cur­rently spec­u­la­tive even in prin­ci­ple, and probably far-off in prac­tice, would surely con­sti­tute an ep­och­al dis­cov­ery,” re­search­ers wrote in a pa­per de­tail­ing their stu­dy. The work ap­pears in the Sep­tem­ber is­sue of the re­search jour­nal Phys­i­cal Re­view D.

 

Cos­mol­o­gists gen­er­ally hold that even if oth­er un­iverses ex­ist, a con­tro­ver­sial idea it­self, they would­n’t be vis­i­ble, and that test­ing for their ex­istence would be hard at best.

 

But the new stu­dy, by three sci­en­tists at the Un­ivers­ity of Cal­i­for­nia, San­ta Cruz, pro­poses that neigh­bor­ing un­iverses might leave a vis­i­ble mark on our own—if, per­chance, they have knocked in­to it. For such a scar to be de­tect­a­ble, they add, the col­li­sion might have had to take place when our un­iverse was very young. Just how the bruise might look re­mains to be clar­i­fied, they say.

 

“The ques­tion of what the af­ter­math of a col­li­sion might be is still quite open,” wrote Mat­thew C. John­son, one of the re­search­ers, in an e­mail. One the­o­ry even holds that a clash be­tween un­iverses could de­stroy the cos­mos we know. But John­son, now at the Cal­i­for­nia In­sti­tute of Tech­nol­o­gy in Pas­a­de­na, Calif., and col­leagues are ex­am­in­ing quite a dif­fer­ent sort of sce­nar­i­o.

 

Sev­er­al lines of rea­son­ing in mod­ern phys­ics have led to pro­pos­als that there are oth­er un­iverses. It’s a rath­er dodgy con­cept on its face, be­cause strictly speak­ing, “the un­iverse” means ev­er­ything that ex­ists. But in prac­tice, cos­mol­o­gists of­ten loos­en the def­i­ni­tion and just speak of “a un­iverse” as some sort of self-en­closed whole with its own phys­i­cal laws.

 

Such a pic­ture, in con­cept, al­lows for oth­er un­iverses with dif­fer­ent laws. These realms are of­ten called “bub­ble un­ivers­es” or “pock­et un­ivers­es”—partly to side­step the awk­ward def­i­ni­tional is­sue, and partly be­cause many the­o­rists do in­deed por­tray them as bub­ble-like.

 

A key thread of rea­son­ing be­hind the idea of bub­ble un­iverses, which are some­times col­lec­tively called a “mul­ti­verse,” is the find­ing that seem­ingly emp­ty space con­tains en­er­gy, known as vac­u­um en­er­gy. Some the­o­rize that un­der cer­tain cir­cum­stances this en­er­gy can be con­vert­ed in­to an ex­plo­sively grow­ing, new un­iverse—the same pro­cess be­lieved to have giv­en rise to ours. The­o­ret­i­cal phys­i­cists in­clud­ing Mi­chio Kaku of ­city Col­lege of New York ar­gue that this might go on con­stant­ly—he has called it a “con­tin­ual gen­e­sis”—cre­at­ing many un­iverses, coex­isting not un­like bub­bles in a foamy bath.

 

How might one de­tect anoth­er un­iverse? John­son and his col­leagues rea­son that any col­li­sion be­tween bub­bles would, like all col­li­sions, pro­duce af­ter­ef­fects that prop­a­gate in­to both cham­bers. These ef­fects would probably take the form of some ma­te­ri­al ejected in­to both sides, John­son said, al­though just what is un­known. This would in turn af­fect the dis­tri­bu­tion of mat­ter in each pock­et un­iverse.

 

If such col­li­sions hap­pened re­cent­ly, they might be un­de­tect­a­ble be­cause our un­iverse might be too huge to be markedly af­fected; but not so if the events took place long enough ago, ac­cord­ing to the Un­ivers­ity of Cal­i­for­nia team, whose pa­per is al­so posted on­line. If a knock oc­curred when our ex­pand­ing un­iverse was still very small, they ar­gue, then the af­ter­math might still be vis­i­ble, blown up in size along with ev­er­ything else since then.

 

When the un­iverse was less than a thou­sandth its pre­s­ent size, it’s thought to have un­der­gone a trans­forma­t­ion. As it ex­pand­ed, it be­came cool enough for atoms to form. It then al­so be­came trans­par­ent. Be­fore that, ev­er­ything had been a thick fog, but with ti­ny varia­t­ions in its dens­ity at dif­fer­ent points; dens­er parts would eventually grow and co­a­lesce in­to ga­lax­ies.

 

This fog is still vis­i­ble, be­cause many of the light waves it gave off are just now reach­ing us: this is how as­tro­no­mers ex­plain a faint glow that per­me­ates space, called the cos­mic mi­cro­wave back­ground. It repre­s­ents the edge of our vis­i­ble un­iverse and is de­tected in all di­rec­tions of the sky.

 

A col­li­sion would lead to a re­ar­ranged pat­tern of dens­ity fluctua­t­ions in this back­ground, ac­cord­ing to the Un­ivers­ity of Cal­i­for­nia team. It’s un­clear just how this re­ar­range­ment would look, but it would probably ap­pear as some sort of ar­ea of ir­reg­u­lar­ity cen­tered on a patch of the sky—s­ince “each col­li­sion will af­fect a disc on our sky,” John­son wrote in an e­mail. An anal­o­gy: if you lived in a beach ball and it bounced off anoth­er beach ball, you’d see a change in a cir­cu­lar ar­ea of your wall.

 

“Noth­ing like this has pre­s­ently been ob­served, al­though no one has ev­er looked for this par­tic­u­lar sig­nal,” John­son added.

 

On the oth­er hand, re­search­ers have found at least one strik­ing ir­reg­u­lar­ity in the back­ground glow—a “cold spot,” thought to be re­lat­ed to a vast and anom­a­lous void in the cos­mos. Could that be the mark of a sep­a­rate un­iverse? “I’m go­ing to re­main com­pletely non­com­mit­tal” on that, John­son said. “I can’t even tell you if it would be a hot spot or a cold spot.” Tem­per­a­ture varia­t­ions in the cos­mic mi­cro­wave back­ground are be­lieved to re­flect dens­ity varia­t­ions in the early un­iverse.

 

John­son and col­leagues stressed that their pro­pos­al may be only the be­gin­ning of a long, pains­tak­ing re­search pro­gram. “Con­nect­ing this pre­dic­tion to real ob­serva­t­ional sig­na­tures will en­tail both dif­fi­cult and com­pre­hen­sive fu­ture work (and probably no small meas­ure of good luck­),” they wrote. But “it ap­pears worth pur­su­ing.”

 

Link: http://www.world-science.net/exclusives/071011_universes.htm

[SWIM]

Well, if infinity is *truly* infinite, then not only do other universes exist, they are countless. In infinity the existence of just one suggests the existence of countless, infinite others, and also variations of the same.

 

It is hard for anyone including myself to grasp the concept of infinity. It is equally hard or harder for a christian to grasp it. Eternity, time without end, would make our lifespan so brief it would be immeasurably short, yet what is done in just a twinkling of an eye, is said to be grave enough for you to be tortured forever and ever. The injustice in such a notion is virtually immeasurable.

[Dave]

Why wouldn't there be other Universes? Infinity is pretty big.

[Guest Marty]

I got a question:

 

These scienctists are speculating that other universes may have bumped into ours, and they want to look for evidence for it, but they have no idea what a "bruise" may look like.

 

How is this any different than a creationist starting with an idea and looking for evidence to support it? This seems silly and futile to me. Maybe if we found something and couldn't explain it, but to come up with an idea that could very well be impossible to observe or prove and then look for the evidence for that assumption, dosen't ring as intellectually honest to me.

 

Am I missing something here? I worked late last night, maybe I'm just tired still?

[SWIM]

I got a question:

How is this any different than a creationist starting with an idea and looking for evidence to support it?

 

Am I missing something here? I worked late last night, maybe I'm just tired still?

 

Science starts with an idea or speculation. It then searches for supporting logic and facts, where religion starts with an idea or speculation and then looks for answers in a book, or prayer. A *very* big difference. Science arrives at *ideas* based on logical probablities, and when it is somehow discovered to be impossible it is quickly abandoned or revised. Religion holds on tight once it thinks a theory is sound. Religion is unconcerned with tests, or mathimatical equations, religion has room for faith, visions and dreams.

 

Big big difference.

[Dhampir]

Scientists typically don't dismiss evidence that speaks against their hypothesis. To speculate that theres a magic sky man is equally a hypothesis as the idea that there may be some way to observe other universes.

[Ouroboros]

Marty,

 

The main difference is that scientists won't start a "Multiverse Church", start working on changing the laws to make sure we please the Multiverse or else, and they won't start pray to it either. A scientist does not (or at least should not) hold a hypothesis to be a religious idea and should be able to drop the idea if there's evidence to the contrary. If he can't, he's starting to fall in love with the idea, instead of observed reality, and it is known to have happened. Usually those kind of situations are resolved within a few years tops. The N-Ray is a perfect example of how some scientists got a large part of the world fascinated by a phenomenon that later proved to be completely bogus. They didn't intend it to be, but the mind is easily tricked, and sometimes we can't separate cause and action from each other and we think reversed to what is really happening. Lamarck's type of evolution was also a very hot item for quite a while until it was proven to be wrong. (Soviet pretty much was starving for a long time because they believed in Lamarck instead of Darwin)

 

And another big difference is that scientist do start with a hypothesis, but from it they figure out ways of testing and proving the hypothesis. If the evidence and tests support it, it becomes a theory. Now with God, we can start with a hypothesis, but we can't test the God hypothesis, because when we do it usually fails and the believers claim that "you can't test God". So in the end God is untestable, and can never be a theory. People can keep him as a hypotheis if they so want, which is basically religion.

[Dave]

Scientists typically don't dismiss evidence that speaks against their hypothesis. To speculate that theres a magic sky man is equally a hypothesis as the idea that there may be some way to observe other universes.

From what I've seen there is no evidence to speak against their "hypothesis". I don't see any "hypothesis"! I do see some dreaming, some thinking, some wondering, but nothing that anyone could pin any hypothesis or theory on. It's a nice idea but we don't know enough to come up with anything other than it's something to ponder.

[Ouroboros]

From what I understand the multiverse idea is not just a fancy dream but is a hypothesis. There are a couple of scientists that solved some problems using math including multiple dimensions and a multiverse. One of them is the problem with the weak force gravity. It seems like a multiverse with some "spillover" effects can explain why it is weak but yet reaches so far. That doesn't mean it's proven or a fact, but it's not just a cardhouse without support. Real scientists do ponder it as the solution.

[Grandpa Harley]

EDIT - Written before I read Hans' post!

 

The concept of M-brane or P-brane universes does explain something the sky daddy 'hypothesis' doesn't... the relative 'weakness' of gravity compared to the other forces (strong nuclear force, weak nuclear force, and electro-magnetism) Of course, Goddidit removes the 'hypothesis' from the whole ball game.

 

I want to visit the parallel universe where Gotham, Metropolis and Central City exist... One thing about the DC universe, Carl Sagan's tea diary must have been very busy up to his death...

 

The Elegant Universe covers this better than I can

 

you can find the other parts from the link

[Ouroboros]

I'd say M-brane and P-brane hypothesis say more than No-Brain and Pee-Brain Morontheists...

[Grandpa Harley]

Well, it seems to be Hawking's major view on the subject, and the guy is usually something approaching 'right'... so I'll put me pound there.

 

His take on a God in the traditional (Classical) sense is that if the observable universe does work inthe way most of the models are pointing, there isn't much for a 'god' to do...

[Dave]

From what I understand the multiverse idea is not just a fancy dream but is a hypothesis. There are a couple of scientists that solved some problems using math including multiple dimensions and a multiverse. One of them is the problem with the weak force gravity. It seems like a multiverse with some "spillover" effects can explain why it is weak but yet reaches so far. That doesn't mean it's proven or a fact, but it's not just a cardhouse without support. Real scientists do ponder it as the solution.

Is it more speculation than a hypothesis? Anyway..... I always say that a person with no dreams has no where to go. Science, out on the fringes, has dreams. Not necessarialy a direction that they must advance to, but like I said, something to ponder. The support for multiverses, as explained to me by the one physicist I know, is not all that great and is mostly speculation. Sure there is some "math" to back it up, but once it comes off of the paper and out into reality, it fades away. Will they find proof some day? Maybe.... it's something to ponder about.

[Islington]

Marty,

 

The main difference is that scientists won't start a "Multiverse Church", start working on changing the laws to make sure we please the Multiverse or else, and they won't start pray to it either. A scientist does not (or at least should not) hold a hypothesis to be a religious idea and should be able to drop the idea if there's evidence to the contrary. If he can't, he's starting to fall in love with the idea, instead of observed reality, and it is known to have happened. Usually those kind of situations are resolved within a few years tops. The N-Ray is a perfect example of how some scientists got a large part of the world fascinated by a phenomenon that later proved to be completely bogus. They didn't intend it to be, but the mind is easily tricked, and sometimes we can't separate cause and action from each other and we think reversed to what is really happening. Lamarck's type of evolution was also a very hot item for quite a while until it was proven to be wrong. (Soviet pretty much was starving for a long time because they believed in Lamarck instead of Darwin)

 

And another big difference is that scientist do start with a hypothesis, but from it they figure out ways of testing and proving the hypothesis. If the evidence and tests support it, it becomes a theory. Now with God, we can start with a hypothesis, but we can't test the God hypothesis, because when we do it usually fails and the believers claim that "you can't test God". So in the end God is untestable, and can never be a theory. People can keep him as a hypotheis if they so want, which is basically religion.

 

Wonderfully stated Han!

Don't want to think too much about this topic (I usualy get Headaches from that) but would go for Steve Hawkings Books if I ever find the time. Maybe I will after reading my recently aquierd Books from Asimov.

[Ouroboros]

Is it more speculation than a hypothesis?

I could be wrong, so don't take it as a fact. The reason why I thought it was, is because I saw a science program where two different scientists were interviewed (those pesky theoretical physicists that only deal with formulas - the kind that write a formula for best mix for the coffee brewer to make the perfect coffee kind ...) and they had tried to solve different problems (the were unrelated in their research too btw), and they both had come to the point where the multiverse idea helped them solve their dilemma. Now, I do know a little science, but I'm not quite that good to remember exactly the details, because I wasn't watching the show, rather channel-hopping and happened to see it. One of them got gravity worked out with the help of it, and that's all I can remember.

 

This of course doesn't validate it, but it seems to be a bit more than a pipe-dream.

 

The problem, IMO, is that sometimes a certain model can fit, but there might be other models that could fit too but no one thought of them yet. Like the Newton's formulas were based on a model that fit perfectly well, up to a third of the speed of light (or was it a 9/10th?). And then we had the relativity that fits well too, but doesn't fit exactly since it doesn't solve the quantum level. Then we get a multiverse model that fits, but maybe it's not the real model since it could fit for the data we have, but it doesn't fit for future unknown data.

 

I guess we just have to wait and see.

 

Anyway..... I always say that a person with no dreams has no where to go. Science, out on the fringes, has dreams. Not necessarialy a direction that they must advance to, but like I said, something to ponder. The support for multiverses, as explained to me by the one physicist I know, is not all that great and is mostly speculation. Sure there is some "math" to back it up, but once it comes off of the paper and out into reality, it fades away. Will they find proof some day? Maybe.... it's something to ponder about.

I agree.

 

--edit--

 

What do you think of the argument that if a multiverse is in fact true, that it means there is one universe for every given situation, basically there would be at least one universe that did have a supreme being in control, and it opens up the possibility that this universe could be such a divine-controlled-universe? (I think evidence show the opposite though)

[Dave]

...... and they had tried to solve different problems (the were unrelated in their research too btw), and they both had come to the point where the multiverse idea helped them solve their dilemma.....

Then it is just a filler in a blank spot in their knowledge. A "hypothesis" of the gaps. When the gap is filled in, that hypothesis/conjecture could get tossed out.

This of course doesn't validate it, but it seems to be a bit more than a pipe-dream.

Not much more than a pipe dream.

 

The problem, IMO, is that sometimes a certain model can fit, but there might be other models that could fit too but no one thought of them yet. Like the Newton's formulas were based on a model that fit perfectly well, up to a third of the speed of light (or was it a 9/10th?). And then we had the relativity that fits well too, but doesn't fit exactly since it doesn't solve the quantum level. Then we get a multiverse model that fits, but maybe it's not the real model since it could fit for the data we have, but it doesn't fit for future unknown data.

All that tells me is that we don't have all the answers. We seem to have figured out how the big stuff works, but when we get down to the minute details, we've hit a few brick walls.

What do you think of the argument that if a multiverse is in fact true, that it means there is one universe for every given situation, basically there would be at least one universe that did have a supreme being in control, and it opens up the possibility that this universe could be such a divine-controlled-universe? (I think evidence show the opposite though)

I wouldn't buy that one for a second. That seperate Universe for every possible situation is a bunch of New Age "creative" interpretation.

[Ouroboros]

...... and they had tried to solve different problems (the were unrelated in their research too btw), and they both had come to the point where the multiverse idea helped them solve their dilemma.....

Then it is just a filler in a blank spot in their knowledge. A "hypothesis" of the gaps. When the gap is filled in, that hypothesis/conjecture could get tossed out.

This of course doesn't validate it, but it seems to be a bit more than a pipe-dream.

Not much more than a pipe dream.

I thought a "hypothesis" was basically an unproven idea in the philosophy of scientific. While a pipe dream is more of "everyone knows this is just bullshit". I read a paper by some scientist that called the multiverse a hypothesis, so I wonder why the scientist you know doesn't? What is the requirement for something to be a hypothesis? After all, one of the definitions for the word is "guess" or "assumption".

[Dave]

I thought a "hypothesis" was basically an unproven idea in the philosophy of scientific.

Yes, if you wish to use the exact, technical, black and white, definition of the word. How about a little grey area?

While a pipe dream is more of "everyone knows this is just bullshit".

I wouldn't put it like that. This multiverse thing isn't a "pipe dream", nor (according to me) fit the exact definition of a hypothesis.

I read a paper by some scientist that called the multiverse a hypothesis, so I wonder why the scientist you know doesn't? What is the requirement for something to be a hypothesis? After all, one of the definitions for the word is "guess" or "assumption".

Why can't a hypothesis cover a range from wild speculation to something based on solid observations? As you can see, sometimes, I like a lot of grey area. I don't need to fit everything into a narrow niche.

[Ouroboros]

I thought a "hypothesis" was basically an unproven idea in the philosophy of scientific.

Yes, if you wish to use the exact, technical, black and white, definition of the word. How about a little grey area?

Or green. I like green... (Oh, I can feel that martinin...)

 

While a pipe dream is more of "everyone knows this is just bullshit".

I wouldn't put it like that. This multiverse thing isn't a "pipe dream", nor (according to me) fit the exact definition of a hypothesis.

Ah, good. Then we're in agreement.

 

I read a paper by some scientist that called the multiverse a hypothesis, so I wonder why the scientist you know doesn't? What is the requirement for something to be a hypothesis? After all, one of the definitions for the word is "guess" or "assumption".

Why can't a hypothesis cover a range from wild speculation to something based on solid observations? As you can see, sometimes, I like a lot of grey area. I don't need to fit everything into a narrow niche.

Absolutely. I do agree. Hypothesis can cover anything that fits the observation. Even the wildest ideas. And it just comes down to how to prove it.

 

I really like the idea of a multiverse, because it does make sense. Infinity withint infinity. God is just even further away... beyond the edge of the multiverse... wherever that might be. I think it's somewhere on a nice island, with a lot of nice women, and a martini in your hand...

[Dave]

Absolutely. I do agree. Hypothesis can cover anything that fits the observation. Even the wildest ideas. And it just comes down to how to prove it.

Kind of like the shot gun approach, or a "idea session" where you just throw out any idea that comes to mind no matter how silly. I've been in a session like that where a silly idea triggered someone to come up with the solution.

 

I really like the idea of a multiverse, because it does make sense. Infinity withint infinity. God is just even further away... beyond the edge of the multiverse... wherever that might be. I think it's somewhere on a nice island, with a lot of nice women, and a martini in your hand...

That's on the pipe dream end of it all.

[Oldjew]

I have always believe there were and also other planets with humans on them, but my Fundy friend gets real unset over that claiming it is not in the bible therefore there is no other planets with humans.

 

But the bible says "in my father's house are many mansions." God's house is the universe and the earth is a mansion, so I believe he (Jesus) meant that there are other planets with people on them and perhaps they have religions too.

 

Even though I no longer believe in the bible the writers may have thought it possible people lived on other planets.

[Ouroboros]

The day they find life on other planets, the fundies will build a rocket and fill it with Bibles...

 

...

 

 

I just wonder what the aliens will send back to us...

[Amethyst]

This is very interesting. I've been wondering about it for quite some time, actually.

[Tabula Rasa]

EDIT - Written before I read Hans' post!

 

The concept of M-brane or P-brane universes does explain something the sky daddy 'hypothesis' doesn't... the relative 'weakness' of gravity compared to the other forces (strong nuclear force, weak nuclear force, and electro-magnetism) Of course, Goddidit removes the 'hypothesis' from the whole ball game.

 

I want to visit the parallel universe where Gotham, Metropolis and Central City exist... One thing about the DC universe, Carl Sagan's tea diary must have been very busy up to his death...

 

The Elegant Universe covers this better than I can

 

you can find the other parts from the link

 

Being the big ol' anime and manga geek I am, I'm also rather fond of the multiverse hypothesis. While I'd no doubt love to visit the worlds that allow all the magical girl/giant robot/ catgirl stuff, I'd like also like to visit the universes of some shows/manga that don't deviate much from the natural laws of our own.

I'd visit Love Hina and straight jacket Naru and give her a tranquilizer shot for her own good. I'd also visit Ai Yori Aoshi and try to hang out with Aoi, Kaoru and the rest of the gang. I'd also like to look up Hibiki Amawa of I, My Me, Strawberry Eggs, buy him a few beers and get his perspective on what it was like walking in a woman's shoes.(In the series, he disguised himself as a woman to get a job at a private jr high to prove to the man hating female principal that men are just as capable as women of loving and nurturing their students.)

 

On the more fantastic side, I'd visit Sakura and Tomoyo of Card Captor Sakura before Li Syoaran shows up and try to talk Tomoyo into telling Sakura how she really feels, citing my own instance of loving someone from afar, and how it's better to let them know, than never telling them and always wondering how things might have been.

 

Just a few more and the fanboying's over: I'd challenge Akari Kanzaki (Battle Athletes) to a foot race, ask Tenchi Masaki what his secret with women is, ask Mihoshi out on a date, and last but not least, if it didn't turn me into a ghoul, offer to let Seras-the badass, but sweet and gentle vampiress from Hellsing to sip a pint from me.( Be gentle with me Seras, PLEASE be gentle!)