First observational test of the 'multiverse'

Aug 03, 2011

The theory that our universe is contained inside a bubble, and that multiple alternative universes exist inside their own bubbles – making up the 'multiverse' – is, for the first time, being tested by physicists.

Two research papers published in Physical Review Letters and Physical Review D are the first to detail how to search for signatures of other universes. Physicists are now searching for disk-like patterns in the cosmic microwave background (CMB) radiation - relic heat radiation left over from the Big Bang – which could provide tell-tale evidence of collisions between other universes and our own.

Many modern theories of fundamental physics predict that our universe is contained inside a bubble. In addition to our bubble, this `multiverse' will contain others, each of which can be thought of as containing a universe. In the other 'pocket universes' the fundamental constants, and even the basic laws of nature, might be different.

Until now, nobody had been able to find a way to efficiently search for signs of bubble collisions - and therefore proof of the - in the CMB radiation, as the disc-like patterns in the radiation could be located anywhere in the sky. Additionally, physicists needed to be able to test whether any patterns they detected were the result of collisions or just random patterns in the noisy data.

A team of cosmologists based at University College London (UCL), Imperial College London and the Perimeter Institute for Theoretical Physics has now tackled this problem.

"It's a very hard statistical and computational problem to search for all possible radii of the collision imprints at any possible place in the sky," says Dr Hiranya Peiris, co-author of the research from the UCL Department of Physics and Astronomy. "But that's what pricked my curiosity."

The team ran simulations of what the sky would look like with and without cosmic collisions and developed a ground-breaking algorithm to determine which fit better with the wealth of CMB data from NASA's Wilkinson Microwave Anisotropy Probe (WMAP). They put the first observational upper limit on how many bubble collision signatures there could be in the CMB sky.

Stephen Feeney, a PhD student at UCL who created the powerful computer algorithm to search for the tell-tale signatures of collisions between "bubble universes", and co-author of the research papers, said: "The work represents an opportunity to test a theory that is truly mind-blowing: that we exist within a vast multiverse, where other universes are constantly popping into existence."

One of many dilemmas facing physicists is that humans are very good at cherry-picking patterns in the data that may just be coincidence. However, the team's algorithm is much harder to fool, imposing very strict rules on whether the data fits a pattern or whether the pattern is down to chance.

Dr Daniel Mortlock, a co-author from the Department of Physics at Imperial College London, said: "It's all too easy to over-interpret interesting patterns in random data (like the 'face on Mars' that, when viewed more closely, turned out to just a normal mountain), so we took great care to assess how likely it was that the possible bubble collision signatures we found could have arisen by chance."

The authors stress that these first results are not conclusive enough either to rule out the multiverse or to definitively detect the imprint of a bubble collision. However, WMAP is not the last word: new data currently coming in from the European Space Agency's Planck satellite should help solve the puzzle.

Explore further: The unifying framework of symmetry reveals properties of a broad range of physical systems

More information: 'First Observational Tests of Eternal Inflation' and 'First Observational Tests of Eternal Inflation: Analysis Methods and WMAP 7-Year Results' published online in Physical Review Letters and Physical Review D
arxiv.org/abs/1012.3667

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hush1
1.4 / 5 (10) Aug 03, 2011
"...imposing very strict rules on whether the data fits a pattern or whether the pattern is down to chance..."
- Dr Daniel Mortlock, a co-author from the Department of Physics at Imperial College London.

What are the chances?*

*That those very strict rules are from mathematics. And mathematics exhibits no pattern?
antialias_physorg
1.9 / 5 (8) Aug 03, 2011
It's a very hard statistical and computational problem to search for all possible radii of the collision imprints at any possible place in the sky,

It is? Fourier analysis of the sky using radial distributions stating at each point would seem an obvious (and rather easily performed) way to do it.

However, I'm not sure why collisions imprints need to be confined to disc shapes. Not all universes need to expand in a bubble but could do so asymmetrically (?). In that case we might also see oblong/asymmetric elipsoid imprints on the CMB
macsglen
4.5 / 5 (4) Aug 03, 2011
"In the other 'pocket universes' the fundamental constants, and even the basic laws of nature, might be different."
If that's true, how would we even detect, let alone recognize, a collision with our own universe?

If the physical laws of an alternate universe were different, it may not be bubble-shaped . . . or, it may not interact with our CMB . . .
IanVand
3 / 5 (4) Aug 03, 2011
It may be true that other multiverses aren't disc shaped. This experiment will identify that.
Donutz
5 / 5 (10) Aug 03, 2011
It may be that some universes will produce disk shaped imprints and some won't. However, the disk-shaped imprints will be easier to detect presumably, so that's what they're going with for a first cut. I don't think they'd actually learn anything more by trying to look for the complex ones first.
NeuroPulse
3.8 / 5 (5) Aug 03, 2011
If our universe has collided with others, why don't we see the others? They should be overlapping. The universe has expanded since the patterns in the CMB were made, so the overlap should have increased.

Can anyone explain?
antialias_physorg
3.7 / 5 (6) Aug 03, 2011
Wasn't there an article not long ago that claimed that any radial symmetric pattern in the CMB was evidence of a 'Big Bounce' ?

How do we distinguish that from a multiverse collision?

Additionaly: Nothing says that other universes of the multiverse have the same number of (macroscopic) dimensions that we do. Impacts with those should look...erm...I have no clue what they should look like but I hardly think disc-shaped will be it.
Sonhouse
4.8 / 5 (5) Aug 03, 2011
Well, if you press two spherical balloons together, the place where they touch would describe a circular area, in short, a disk. Maybe this is a 3 dimensional analogue of the multiverse.

If they were not spherical, say an ellipse and a sausage, depends on exactly what sides are in contact and there would be a shape, could be a sphere or an elongated circle or an ellipse.

Sounds like this program could detect those kind of shapes.
Noumenon
4.8 / 5 (52) Aug 03, 2011
Wasn't there an article not long ago that claimed that any radial symmetric pattern in the CMB was evidence of a 'Big Bounce' ?

How do we distinguish that from a multiverse collision?


I was about to post this. If I recall it was suggested or at least promoted by Penrose.
SmartK8
2.5 / 5 (2) Aug 03, 2011
To write "our universe is contained inside a bubble" is misleading. At best the space we perceive is a surface of that bubble. If we were inside the bubble we could've leave it, and enter another bubble. It would just still be three-dimensional space as opposed to multidimensional construct.
Cave_Man
4.2 / 5 (13) Aug 03, 2011
Ok but doesn't this test make an unreasonable assumption about the size of other universes. This would be a great way to look for other universes that are roughly the same size as ours, but since there is the potential for infinite other universes then wouldn't all the interference from atom or apple sized universes colliding with ours effectively haze the data?

I like that quote from Douglas Adams Hitchhikers "Trilogy":

It is known that there are an infinte number of worlds, simply because there is an infinite amount of space for them to be in. However, not every one of them is inhabited. Any finite number divided by infinity is as near nothing as makes no odds, so the average population of all the planets in the Universe can be said to be zero. From this it follows that the population of the whole Universe is also zero, and that any people you may meet from time to time are merely products of a deranged imagination.
extinct
1.8 / 5 (4) Aug 03, 2011
2 things

1: they mention an "observational upper limit" on bubble collisions - to simplify, think of a 3D sphere; it can be surrounded & touched by exactly 12 other spheres. IMHO, 9 - 15 is a good starting range for their "limit".

2: if you measure a distant object's redshift *before* a collision bubble passed between you and it, & then measure again *after*, you'd get 2 different readings! i call it the "redshift shift." it's analogous to the visual shockwave caused by high explosives. unfortunately, we may never directly observe this, because it happens over millions of years
Isaacsname
4 / 5 (4) Aug 03, 2011
I find it strangely funny that modern physics predicts something that likely every child has thought of growing up.

I personally thought of a foam of bubbles. If things were like that, perhaps expansion in one universe causes collapse in bordering universes due to boundary pressure,..for lack of a better term.
antialias_physorg
3.7 / 5 (7) Aug 03, 2011
I find it strangely funny that modern physics predicts something that likely every child has thought of growing up.

Even physicists were children once. The difference is: children won't come up with a way to test their theory.

(another difference is that children will also come up with a lot of other stuff that makes no sense - so the occasional parallel to genuine reserach shouldn't be too surprising)
extinct
2 / 5 (4) Aug 03, 2011
by the same token, our universe's expansion need not necessarily be a constant value. it probably expands at different rates in different directions, and we only observe what we can from here. if the multiverse is real, then our universe is held in some higher equilibrium by external-to-it forces so 2 things need to be considered: 1) the accelerated expansion may not eternal; we may be headed for a big crunch eventually, & 2) a big bang and big crunch may be unnecessary alltogether. maybe our bubble has just always existed (within the laws of physics), and just grows & shrinks based on "wall pressure"
Isaacsname
4 / 5 (2) Aug 03, 2011
I find it strangely funny that modern physics predicts something that likely every child has thought of growing up.

Even physicists were children once. The difference is: children won't come up with a way to test their theory.

(another difference is that children will also come up with a lot of other stuff that makes no sense - so the occasional parallel to genuine reserach shouldn't be too surprising)


True, I also think it's interesting that the meme of the multiverse is something so deeply ingrained in us that it not only is thought of by what we see as simple minds, children, but also has become a mainstay of study.

There's something beautiful about that, as corny as it sounds.

Isaacsname
4.8 / 5 (4) Aug 03, 2011
by the same token, our universe's expansion need not necessarily be a constant value. it probably expands at different rates in different directions, and we only observe what we can from here. if the multiverse is real, then our universe is held in some higher equilibrium by external-to-it forces so 2 things need to be considered: 1) the accelerated expansion may not eternal; we may be headed for a big crunch eventually, & 2) a big bang and big crunch may be unnecessary alltogether. maybe our bubble has just always existed (within the laws of physics), and just grows & shrinks based on "wall pressure"


Right, ...so, if we were in a foam of universes that fluctuated inward/outward, the boundaries wouldn't be circular, they'd be like...foam, ..and since there is a limit to how far out we can see, bound by c, all we can see is a spherical view, unless c varies.

Which is interesting in that it sounds like a quantum foam.

Damn you infinity..Noooooooooooooooooooooooooooooooooo
krundoloss
1 / 5 (1) Aug 03, 2011
I think there may be some sort of infiniteness to the universe, like it loops in on itself to infinity. We probably wont understand it until we can concieve it, like all things.
Callippo
1 / 5 (5) Aug 03, 2011
IMO it's not circles but foamy density fluctuations of nested dodecahedron geometry - the most compact arrangement of observable particles. And they're all inside of our Universe.
TheGhostofOtto1923
1 / 5 (3) Aug 03, 2011
Physicists are now searching for disk-like patterns in the cosmic microwave background (CMB) radiation

I think they must be something like this:
http://upload.wik...lico.JPG
Isaacsname
3.7 / 5 (3) Aug 03, 2011
Physicists are now searching for disk-like patterns in the cosmic microwave background (CMB) radiation

I think they must be something like this:
http://upload.wik...lico.JPG


What is that, a pic of one of your old headwounds ?
k_olfers
4.8 / 5 (5) Aug 03, 2011

I like that quote from Douglas Adams Hitchhikers "Trilogy":

It is known that there are an infinte number of worlds, .....


Now I like the quote, and I'm no math wizard but: is a fraction of infinity not still infinity? In other words, if a fraction of an infinite number of worlds has life, then an infinite number of worlds have life.

So the average life in the universe would still be the fraction, and not zero.
komone
not rated yet Aug 03, 2011
We can't see inside a black hole. We can't see a singularity. But we are told it is there because math predicts it. We can see evidence of black holes but I don't recall evidence of singularities, i.e. physical infinities. How is it that the math that so wonderfully exactly describes the world we can see allows infinities?
Ramael
3.7 / 5 (6) Aug 03, 2011
If conventional space is limited to within the universe, what makes anyone think that other universes are simply "bumping" around at all?
Isaacsname
not rated yet Aug 03, 2011
Interesting paper, most was over my head but the parts I understood were interesting, to say the least. Looks to be some interesting cited/linked papers at the bottom too.

Aw man..theres an ant in my coffee
Brandenburg
4.4 / 5 (5) Aug 03, 2011
If it's being suggested that each universe likely contains its own laws, can't we assume that the multiverse that contains them then as its own set of laws ruling the behavior of various universes? Pushing this idea further, maybe there are multiple multiverses contained in an ultraverse.....and then a megaverse and then and then and then...

The cool thing about physics is that you can always ask just one more question and open up and endless realm of new areas to study.

From a lay point of view, it's all incredibly fascinating.
cdt
4.8 / 5 (4) Aug 03, 2011
If our big bang created space, and presumably the space of other universes was created separately, what reason is there to think that the separate spaces share any dimensions and can interact at all?
Isaacsname
not rated yet Aug 03, 2011
How do we know that the universe doesn't cavitate instead of collapsing to some small size ?

Warning *obnoxious soundtrack for video*

http://www.youtub...YBAhY2PQ

I know it's probably a dillbrain question, but all the same, aren't most of the maths for cosmology based on equations for fluid dynamics ?
georgert
5 / 5 (1) Aug 03, 2011
Wasn't there an article not long ago that claimed that any radial symmetric pattern in the CMB was evidence of a 'Big Bounce' ?

How do we distinguish that from a multiverse collision?


I was about to post this. If I recall it was suggested or at least promoted by Penrose.


Roger Penrose presented this theory in a public lecture at the Perimiter Institute, which is viewable at:
http://www.perime..._id=7276
Isaacsname
5 / 5 (1) Aug 03, 2011
Since I can't stop commenting, I just wanted to add this:

More than a few times I have seen threads pertaining to the subject of " What is possibly outside our universe " in the Physorg forums deleted or locked for the reason that the question doesn't " follow the forum rules ", but yet it is a mainstream area of study and this story is posted on the front page of the website.

Why is that ?
NeuroPulse
5 / 5 (1) Aug 03, 2011
If our big bang created space, and presumably the space of other universes was created separately, what reason is there to think that the separate spaces share any dimensions and can interact at all?


It is my understanding that dimensions do not only exist where there is space. Space is not nothing. That is, it is not the absence of everything. It is filled with virtual particles, and it can bend. That is the space created in the big bang. The fabric of space exists within a greater void of possibly infinite dimensions that would be what is between universes.
verde_sol
not rated yet Aug 04, 2011
You are right Isaacsname, the meme of the Multiverse is part of our global consciousness, from religious ideas and other fantasy worlds to the concepts of art and philosiphy, our species has been fascinated with other existences for a very long time. I've never thought of it that way before, and I think it's beautiful too.
jamesrm
not rated yet Aug 04, 2011
"Space is not nothing. That is, it is not the absence of everything. It is filled with virtual particles, and it can bend"

http://en.wikiped...irac_sea
Pyle
3 / 5 (2) Aug 04, 2011
More than a few times I have seen threads pertaining to the subject of " What is possibly outside our universe " in the Physorg forums deleted or locked for the reason that the question doesn't " follow the forum rules ", but yet it is a mainstream area of study and this story is posted on the front page of the website.
First off, PhysicsForums isn't Physorg. They are affiliated, but not directly linked. The rules on PhysicsForums don't have anything to do with this site. And I agree, they toss out a lot of potential theories on that site, even in the Beyond the SM area. They don't tolerate cranks at all. No fun unless you want to learn "acceptable" science. Universe Today is like that too.
Pyle
5 / 5 (3) Aug 04, 2011
"...imposing very strict rules on whether the data fits a pattern or whether the pattern is down to chance..."
- Dr Daniel Mortlock, a co-author from the Department of Physics at Imperial College London.

What are the chances?*

*That those very strict rules are from mathematics. And mathematics exhibits no pattern?

I am not sure why nobody appreciated this hushie. I liked it. I think you are probably a bit sideways on it, but it is definitely a valid point. You can impose patterns on anything if you aren't careful. I loved the concentric triangleness in one of the Penrose detractor's papers earlier this year.

Check out the other recent article on AGN's and CXBR. Makes me think maybe there are other more likely explanations for concentric circles than bouncing branes even if they "detect" such patterns.
http://www.physor...ink.html
hush1
3 / 5 (2) Aug 04, 2011
Thks Pyle.
By chance(!) I read your comment. The pattern is reading everything I see. (Regardless of rating, lol)

No matter how convoluted, conflated and confusing commentary becomes, there is always Kevinrtrs. Anyone's logic will improve under the auspice of Kevinrtrs.

auspice - Originally denoted the observation of bird flight as a form of divination.

Kevinrtrs: Everyone's favorite.
Chances are I will get a Thank You from him, for this pattern recognition.
antialias_physorg
3.7 / 5 (3) Aug 04, 2011
That those very strict rules are from mathematics. And mathematics exhibits no pattern?

Mathematics exhibits any pattern you wish it to (aside from those which are laid down in the fundamental axioms).

You can impose patterns on anything if you aren't careful.

And there's not much wrong with that as an approach for science to take. Science models things - it does not say 'this is true' or 'that is true'. If the model fits then that is all that is required.

Example:
1,2,3,4,5

There are an infinte amount of formulae that match this sequence (even ones that cannot be shown to be equivalent). Which one is correct? We can't tell. Even observing the next number in the sequence (e.g. 524.998) leaves us with an infinite number of formulae which would have predicted that. All of those formulae are equally 'true' - even though thay may be - in their prediction of th next number - mutually exclusive.

Science isn't about truth. It's about what works.
Isaacsname
not rated yet Aug 04, 2011
More than a few times I have seen threads pertaining to the subject of " What is possibly outside our universe " in the Physorg forums deleted or locked for the reason that the question doesn't " follow the forum rules ", but yet it is a mainstream area of study and this story is posted on the front page of the website.
First off, PhysicsForums isn't Physorg. They are affiliated, but not directly linked. The rules on PhysicsForums don't have anything to do with this site. And I agree, they toss out a lot of potential theories on that site, even in the Beyond the SM area. They don't tolerate cranks at all. No fun unless you want to learn "acceptable" science. Universe Today is like that too.

Ahh, Ok, I get it. Thanks. It can be difficult for laypeople to ask questions without having the formal framework that comes with higher education. However, that said, for somebody like me to inquire whether there are an infinite amount of theories with finite corrections, or
Isaacsname
5 / 5 (1) Aug 04, 2011
Vice versa, and be shut down on the forum, when I should have been gently pointed ( or violently shoved ) to the

http://en.wikiped...rinciple

and

http://en.wikiped...ximation

,..is unerving to say the least. It's like being told you are asking a stupid question, when in reality there are no stupid questions, there are only people who can or can't answer them.

*End of Butthurt report form*
shockr
not rated yet Aug 04, 2011
I always envisaged that for the 'multiverse' to be infinite, it would have to be a series of 'loops'. That is to say that our universe contains many subatomic universes, and our universe exists within another universe above. We say the CMB is a relic from the big bang.. or the furthest that information can be studied. Could it not be that a black hole is actually another universe? So material falling into a BH would appear as CMB within that universe. This would still allow each universe to have it's own constants depending on the fields at work in each universe. Information cannot come back out of a universe like a BH. In this instance, no 'touching bubbles' would be evident, as mass/energy falls into BH. If they find no bubble imprints, does that invalidate their whole theory of a multiverse? Not convinced that universes are just bubbles floating around in nothingness, like some string theory brane..
Pyle
5 / 5 (3) Aug 04, 2011
Science isn't about truth. It's about what works.
I know what you mean, but thought I would clarify for the cranks out there.

Science is about truth - i.e. you can't ignore observations that contradict your "belief system".

Science isn't about truth - All theories are just that, ... theories. They work until they don't and then you tweak or go back to the drawing board until you find one that explains the new observations better (as well as the old observations, usually).
antialias_physorg
4 / 5 (5) Aug 04, 2011
Science is about truth - i.e. you can't ignore observations that contradict your "belief system".

I would formulate it thus:
Science cannot say what is true - but it most definitely can say what is false.
hush1
3 / 5 (2) Aug 04, 2011
"Mathematics exhibits any pattern you wish it to (aside from those which are laid down in the fundamental axioms)."

Nothing truly random about that. Taken from either side: math or humans.

"...imposing very strict rules on whether the data fits a pattern or whether the pattern is down to chance..."
- Dr Daniel Mortlock

"...whether the pattern is down to chance..."
is weakly formulated. Self contradictory.
To know all infinite patterns is impossible. And then to label unknown patterns as random or attributed this to chance is not logical.
vidyunmaya
1.3 / 5 (4) Aug 05, 2011
Sub: Science from ambiguity needs to a long way to comprehend multi-Universe in Cosmos.
Science must take a helping hand in time from nature and Philosophy. Cosmology vedas Interlinks provide a solution.Multi-universe Concept and Cosmic Pot Energy Universe were introduced by me -Dec 1999-cosmologyreview [dot]com-see more in BOOKS BY VIDYARDHI NANDURI [1993-2011]-
http://vidyardhic...pot.com/
Isaacsname
not rated yet Aug 05, 2011
Sub: Science from ambiguity needs to a long way to comprehend multi-Universe in Cosmos.
Science must take a helping hand in time from nature and Philosophy. Cosmology vedas Interlinks provide a solution.Multi-universe Concept and Cosmic Pot Energy Universe were introduced by me -Dec 1999-cosmologyreview [dot]com-see more in BOOKS BY VIDYARDHI NANDURI [1993-2011]-
http://vidyardhic...pot.com/

" Science must take a helping hand in time from nature and Philosophy. "

Science is our description of nature and heavily based on philosophical discourse. Btw, are there any actual links on your blog, or is it just spam ?
socean
not rated yet Aug 06, 2011
I can't find my keys... anyone seen them in an alternate universe?
DavidMcC
not rated yet Aug 06, 2011
You do not need the "bubble" hypothesis to show that a multiverse can develop from simple physics. A version of loop quantum gravity naturally produces on - the extended family of black-hole-based universes.
Tachyon8491
2 / 5 (4) Aug 06, 2011
Apart from all possible topological physical configurations that are speculated upon with regard to the "multiverse" concept, there appear to be no hypothetical constructs for HOW universal subdomains may differ from each other in their physical "laws" - and how then, such subdomains would symptomatically display their interactive boundaries and phase-transitions. Such an approach would appear useful in pointing towards empirical investigation. Once again I need to point out that the plural term "universes" is illegitimate - derived from "unum" - one, and "vertere" - turning (into), this conceptualises "All turned into One." There is nothing "outside" the universe - it comprises ALL that exists. Mutually (partially, attributionally) isolated domains of this should properly be termed "universal subdomains," aggregation of which composes the "multiverse" idea. Most evident factor that could form transitional phase-boundaries between such subdomains is different dimensional composition.
Callippo
1 / 5 (2) Aug 06, 2011
As usualy, the source of the problem here is a misleading university press release, one from University College London entitled First observational test of the multiverse. Somehow the press release neglected to mention something one might think was an important detail, the fact that this First observational test had a null result.

IMO it's not circles but foamy density fluctuations of nested dodecahedron geometry - the most compact arrangement of observable particles. And they're all inside of our Universe.
DavidMcC
5 / 5 (2) Aug 06, 2011
Tachyon8491:"There is nothing "outside" the universe - it comprises ALL that exists. Mutually (partially, attributionally) isolated domains of this should properly be termed "universal subdomains," aggregation of which composes the "multiverse" idea."
That may apply to the Hawkins-type "bubble" multiverse, but, I assert, not to the kind of multiverse that can follow from quantum loop gravity (with a hyperspace continuum that supports quantized vacua). There, the spaces are genuinely different - particles cannot, even in principle, travel from one to another. Only gravity itself can connect them. Therefore, you would have to define "universe" as "all that exists" for that kind of multiverse to be "just more of the universe". However, it then becomes a semantic issue, connected with the ambiguity of the word's definition.
gt000
4 / 5 (1) Aug 06, 2011
Given that the paper concludes with the following statement, one wonders what all the fuss is about.

"The posterior evaluated using the WMAP 7-year data is maximized at Ns = 0 [Ns is the average number of observable bubble collisions over the full sky], and constrains Ns < 1.6 at 68% confidence. We therefore conclude that this data set does not favor the bubble collision hypothesis for any value of Ns."

In other words, they found no evidence to support the existence of a multiverse.
PaulRadcliff
1.7 / 5 (3) Aug 07, 2011
I have seen reports of concentric circles of greater intensity being found in the CMB. Whether these are real or from noise in the data, I can not say. Interesting, if the data gets higher in resolution, and these circles get even MORE defined!!! I'd get that we do have neighbors, perhaps living right beside us in a differently "tuned" dimension of reality. Kinda like the sci-fi show "Sliders". Opens up a whole new fresh can of worms we don't have many clues about. Talk about a complicated Cosmos!!!!
Vendicar_Decarian
1 / 5 (2) Aug 07, 2011
"it probably expands at different rates in different directions" - Whomever

To a high degree of accuracy we know that it doesn't. Such a thing would show up in the CMB.

It doesn't. No convincing asymmetry has been found in the CMB.
Norezar
not rated yet Aug 07, 2011
I really feel like watching Sliders...
Vendicar_Decarian
1 / 5 (3) Aug 07, 2011
Computing the mass of the universe from the Hubble constant and then using that mass to compute the radius of a black hole needed to hold that amount of matter, and you end up with the current radius of the universe.

Light emitted from within the Schwarzschild radius of a black hole can not escape to an arbitrary distance from it's center. Similarly light is constrained to exist within the boundaries of the universe.

I find these similarities very compelling.
NeuroPulse
not rated yet Aug 07, 2011
Computing the mass of the universe from the Hubble constant and then using that mass to compute the radius of a black hole needed to hold that amount of matter, and you end up with the current radius of the universe.


Please give references for this. Since there is plenty of space in the universe, putting all the mass together would take up less space than it currently does.
pianoman
1 / 5 (1) Aug 08, 2011
Can this bubble wall material, if any, be described? What is the space between the bubbles? Did all these universe's all start off with the big bang? There's lots of entertainment here
MP3Car
not rated yet Aug 08, 2011
I find it strangely funny that modern physics predicts something that likely every child has thought of growing up.

Even physicists were children once. The difference is: children won't come up with a way to test their theory.

(another difference is that children will also come up with a lot of other stuff that makes no sense - so the occasional parallel to genuine reserach shouldn't be too surprising)


Just look at all the things we've created that are based on childhood and sci-fi imaginations... aerospace (flight, space travel and to the moon), laser/RF weapons, live satellite imagery, phones on our wrist, cloning animals, and even 3D printing is a pretty novel invention... no, one can't make tea - earl grey, hot; but can make a ton of other things, some of which are virtually impossible to make any other way (such as by using molds or machining).