Thursday, April 10, 2008 | Science : Astronomy | print version

Did pre-big bang universe leave its mark on the sky?

by New Scientist

Thanks to Vaal for the link.

Reposted from:
http://space.newscientist.com/article/mg19826514.300-did-prebig-bang-universe-leave-its-mark-on-the-sky.html?DCMP=ILC-hmts

10 April 2008
From New Scientist Print Edition. Subscribe and get 4 free issues.
Stephen Battersby

WHAT happened before our universe began? According to two theoretical physicists, if there was a universe before ours then it should have been remarkably similar to this one, with the same basic ingredients and properties. It may even be possible to see a faint picture of our parent universe imprinted on the sky.

Questions about a time before the big bang were once thought to be meaningless, because according to Einstein's general theory of relativity, the universe began at a singularity - a mathematical point with infinite density at which all calculations break down.

However, physicists now believe that the theory of relativity is limited and the effects of quantum mechanics would have blurred out the singularity just a little, so at a crucial moment the density of matter and radiation was not infinite. If this was the case, it becomes possible to try to work out what led up to that moment.

In cosmological models based on a theory called loop quantum gravity, our universe has a parent. Loop quantum gravity attempts to meld relativity with quantum mechanics by describing space-time as a constantly rearranging fabric of interconnections. On the smallest scales, around 10-35 metres, that fabric is a tangled mess, but on much larger scales the space and time of our universe look smooth.

The theory predicts that when this fabric is scrunched up, it becomes bouncy. So if the universe before ours was contracting, it would have reached a point of maximum density and then bounced out again in our big bang.

So what would this predecessor have been like? To find out, Parampreet Singh of the Perimeter Institute for Theoretical Physics in Waterloo, Ontario, Canada, and Alejandro Corichi of the National Autonomous University of Mexico, Morelia, applied the equations of loop quantum gravity to a highly simplified model of the universe. They found that the properties of space, such as the quantity of matter and energy it contains, hardly change when the universe goes through the big bounce. "For the simple model considered, the universe is almost exactly the same on other side," says Singh.

It raises the possibility that we could see an imprint of the universe before ours. Singh suggests that the seeds of large-scale structures in our universe, such as superclusters of galaxies, would have been present on the pre-big-bang side. The pattern of those seeds might be preserved in the cosmic microwave background radiation - the relic radiation left behind by the big bang. "If this conclusion holds true, then it is possible that we are going to see signatures of the pre-big-bang universe," says Singh.

A pioneer of loop quantum gravity, Carlo Rovelli at the Centre for Theoretical Physics in Marseille, France, likes the work. "It is quite remarkable that we can begin to address these questions and find the first tentative answers," he says.

But the calculation doesn't convince Martin Bojowald, another loop quantum gravity theorist, based at Pennsylvania State University in University Park. He disagrees with their interpretation of the mathematics and also points out that loop models so far are still very simple.

Bojowald thinks that the universe before the big bang could have been a very different place, perhaps without even the familiar smooth, classical space-time of our world.

Corichi and Singh's paper will appear in Physical Review Letters.

Add to del.icio.us Posted: Thursday, April 10, 2008 | Permalink

Comments 1 - 49 of 49 |

Reload Comments | Back to Top | Page Numbers

1. Comment #158574 by neander on April 10, 2008 at 7:12 pm

I expect thinking like this to upset the loonies. Pushing gods back even farther!

Other Comments by neander

2. Comment #158579 by SmartLX on April 10, 2008 at 7:21 pm

Another spanner in the works of the Cosmological Argument. Yay!

Other Comments by SmartLX

3. Comment #158591 by DasSquid on April 10, 2008 at 7:42 pm

I don't think it's the spanner just yet.

These guys will publish their paper, and it'll be peer reviewed, already there is some resistence against this idea. However if their paper gets through peer revision and becomes a credited scientific theory then it'll become a great spanner.

And just on a personal note, it's one I like, the version of the universe I prefer is the expanding/contracting model, and even though Hawking has pretty much proven that wrong, I still like it, it gives the universe thing the ability to literally be forever.

My musings are completely irrelevant however.

Other Comments by DasSquid

4. Comment #158593 by MaxD on April 10, 2008 at 7:45 pm

So when Scott Bakula did.....

Other Comments by MaxD

5. Comment #158599 by troyreynolds86 on April 10, 2008 at 7:57 pm

Though I am always enthused by the models created by physicist it would behoove us to be cautious about citing theoretical physics in an argument. Mathematics on a blackboard aren't worth much more than musing within a holy book until we have the experimental evidence to back it up. That is, after all, what separates religious thought from scientific thought, and taking any theoretical explanation sans evidence betrays our rational selves and gives the opposition the golden opportunity to paint science as just another field of faith.

Troy

Other Comments by troyreynolds86

6. Comment #158612 by Damien White on April 10, 2008 at 8:23 pm

Isn't this just a new reiteration of the 'galactic heartbeat' model of the universe popular back in the good* old days of the 1970s? If so, do the arguments against that theory still hold true?

*for a given value of good.

Other Comments by Damien White

7. Comment #158654 by Broicher on April 10, 2008 at 9:28 pm

I don't know whether I like the idea of a bouncing universe, somehow I found the idea of colliding m-branes better, because it gave the universe a definite beginning. But what are my favourites compared to science/truth. We are living in exciting times, let's see whether this can become a theory.

Other Comments by Broicher

8. Comment #158665 by rushfan2112 on April 10, 2008 at 10:35 pm

Hmmm....This gives some validity to the "Big Crunch" End of the Universe theory.

Other Comments by rushfan2112

9. Comment #158676 by JanChan on April 10, 2008 at 11:43 pm

Wait, if big bangs are hereditary, what's stopping natural selection to act upon them? And if nothing is, does that mean we might encounter a universe that starts chomping down on other universes?

Other Comments by JanChan

10. Comment #158703 by Adam Morrison on April 11, 2008 at 1:11 am

Re: MaxD

Quantum LOOOOOOOOOOOPPPPP!!! :D

Let's not get all crazy and bring Ziggy into the matter

While I can imagine that there was a physical finite universe before the bang and that the density of the singularity does have its limits, I'm not entirely convinced, especially when using a simplified model. I've heard arguments to the opposite saying that expansion of the universe is accelerating, which I don't think would fit into this model (although that model could be way off). Either way, I'm pretty sure a lot more research needs to be done before we can make any claims to the 'pre-bang' universe.

Other Comments by Adam Morrison

11. Comment #158714 by jawtheshark on April 11, 2008 at 1:23 am

Just a little nit on the cut/paste text:

"On the smallest scales, around 10-35 metres"

The superscript is missing. In the linked article it's there. It does change the meaning quite a bit ;-)

Other Comments by jawtheshark

12. Comment #158720 by Steve Zara on April 11, 2008 at 1:29 am

We shouldn't rush to any conclusions. This is a highly speculative article, making a lot of assumptions.

Other Comments by Steve Zara

13. Comment #158726 by irate_atheist on April 11, 2008 at 1:39 am

Steve -

I agree. About as speculative as a punt on the Grand National, and with less chance of knowing who the winner is.

Other Comments by irate_atheist

14. Comment #158732 by Vaal on April 11, 2008 at 1:43 am

Interesting article. If physical evidence of a parent Universe can be found in our Universe, then it would indicate that there are many Universes. I have leaned toward the Multiverse theory for some time now, as logically as our Universe exists, why shouldn't there be many Universes?

Of course, this is only speculation, and I am the first to admit that quantum physics is way beyond me, even though I have tried to understand it. Perhaps somebody more qualified than myself, being only a layman, on this board can see the fallacies more clearly.

However, it is an interesting time. I wonder how much the new Cern site will show us about the early Universe, or indicate the existence of a Multiverse?

Other Comments by Vaal

15. Comment #158734 by Steve Zara on April 11, 2008 at 1:46 am

Comment #158732 by Vaal
However, it is an interesting time. I wonder how much the new Cern site will show us about the early Universe, or indicate the existence of a Multiverse?

I doubt it will show anything about multiverses, but it will tell us a lot about the early universe. Even if they find no new particles or behaviour of particles, that is a highly significant finding in itself, as indicates that current ideas of how particles acquire inertial mass are wrong.

Other Comments by Steve Zara

16. Comment #158743 by Vaal on April 11, 2008 at 2:05 am

Steve, I did see an article some time ago about some Quantum physicists who claimed they were close to proving the existence of a Multiverse through Quantum mechanics. It probably died a death, as I can't seem to find it, however it would be interesting to know how they would prove it?

Still, as you say, I am looking forward to new insights from the Cern facility, providing they don't create a black hole and suck us all up. :-)

Other Comments by Vaal

17. Comment #158754 by mmurray on April 11, 2008 at 2:31 am

Still, as you say, I am looking forward to new insights from the Cern facility, providing they don't create a black hole and suck us all up. :-)

Maybe that is how the big bang happened. In the parent universe life developed to a level of intelligence that they could build their version of a LHC and it made a black hole which sucked up the universe and it all started again until we could build ours and then ...

OK I know this is not really possible but it's Friday night.

Michael

Other Comments by mmurray

18. Comment #158757 by alexmzk on April 11, 2008 at 2:35 am

The theory predicts that when this fabric is scrunched up, it becomes bouncy.

i really like this.

Other Comments by alexmzk

19. Comment #158761 by Roland_F on April 11, 2008 at 2:48 am

Breaking the NOMA again and entering the last refuge of the "God of the gaps" the theist perception of the universe as the result of a "divine fart".
Let's see if the Planck space craft launched end of 2008 to increase the informations gatherd from WMAP so far, will bring new ideas about the global structure of the (observable) universe.
Plus some more info from the LHC like Higgs or no Higgs .... interesting times ahead !

Other Comments by Roland_F

20. Comment #158767 by epeeist on April 11, 2008 at 3:03 am

Comment #158720 by Steve Zara

We shouldn't rush to any conclusions. This is a highly speculative article, making a lot of assumptions.

Agreed. However, there is a difference between this conjecture and some of the things being put forward by the crowd of loony creationists we seem to have been infected with at the moment.

They are offering predictions and some possibility of testing them. As opposed to the loonies who seem to think you can just make stuff up and a back reference to the bible makes it true by caveat.

Other Comments by epeeist

21. Comment #158793 by aquilacane on April 11, 2008 at 3:41 am

What roles do the other universes beyond our own universe play? What if our universe collides with another universe, what would happen then, would they pass through each other like a galaxy. I'm disturbed that we only ever seem to consider our universe as the only universe, hence the uni. I can imagine several universe existing side by side in a soup of universes.

Other Comments by aquilacane

22. Comment #158796 by Steve Zara on April 11, 2008 at 3:48 am

Comment #158793 by aquilacane

What if our universe collides with another universe, what would happen then, would they pass through each other like a galaxy.

There could be quite a lot of damage. After all, one theory of the origin of matter and energy in our universe is that it was the result of the such a collison.

Collisions between universes are very unlikely, though. It is probable that physically separated universes are separated by unimaginable amounts of space, and receding from each other far faster than the speed of light.

Other Comments by Steve Zara

23. Comment #158819 by Mitchell Gilks on April 11, 2008 at 4:36 am

This is interesting, but nothing knew. For sheer personal preference I also like the sounds of the oscillating universe. Though I think the evidence is more in favor of "the big freeze" with the discovery of the increasing speed of expansion.

Other Comments by Mitchell Gilks

24. Comment #158830 by lievemebe on April 11, 2008 at 5:11 am

Definitely cries out for evidence. I place a lot of credence in "ideas are a dime a dozen" as a reality check. Mind you, some ideas are better than others, some better than my simple math could handle.

Other Comments by lievemebe

25. Comment #158882 by sidfaiwu on April 11, 2008 at 6:29 am

JanChan:

Wait, if big bangs are hereditary, what's stopping natural selection to act upon them?

Mostly the fact that universes don't have environments. There is nothing 'outside' the universe that can cull the 'weaker' universes.

Other Comments by sidfaiwu

26. Comment #158926 by AntonAAK on April 11, 2008 at 7:17 am

What roles do the other universes beyond our own universe play? What if our universe collides with another universe, what would happen then, would they pass through each other like a galaxy. I'm disturbed that we only ever seem to consider our universe as the only universe, hence the uni. I can imagine several universe existing side by side in a soup of universes.

I've always been puzzled by the concept of 'other universes'.

Wikipedia states that 'The Universe is most commonly defined as everything that physically exists' and this is what I've always understood the word to mean.

So how can there be other universes? They would have to be included in this definition and be just part of 'the universe'.

How can you have something that is not included in 'everything'?

Other Comments by AntonAAK

27. Comment #158953 by sidfaiwu on April 11, 2008 at 8:27 am

crazy old man:

I'm puzzled. How in the hell is the universe supposed to contract to a "Big Crunch" (or "Big Bounce", as it were) if dark energy is accelerating its ever-increasing rate of expansion beyond the point of no return?

I'm skeptical about the dark energy hypothesis. It seems physicists have recently been giving names to phenomena they don't yet understand. Galaxies are spinning too fast to say coherent? Gravity from 'dark matter' must explain it! Oh shit! The dark matter hypothesis means that there's too much gravity in the universe to explain the accelerating expansion. It must be caused by 'dark energy'!

They don't seem to consider that their model for gravity may (one again) be incomplete. There could be small, non-linear gravitational effects that are not observable in the near-field but manifest in the far-field. The effects may even be time-dependent. Thus over time, these far-field effects my decay and cause a deceleration and eventual contraction of the universe.

Really, this speculation is beside the point. The Big Bounce hypothesis above only requires that the previous universe undergo a near Big Crunch. Though our universe may be similar, there's nothing in the hypothesis that guarantees that our universe must follow suite and collapse as well.

Other Comments by sidfaiwu

28. Comment #158958 by Border Collie on April 11, 2008 at 8:39 am

I'm gonna go reboot my brain ...

Other Comments by Border Collie

29. Comment #158973 by Luthien on April 11, 2008 at 9:10 am

25. Comment #158882 by sidfaiwu on April 11, 2008 at 6:29 am
JanChan:

Wait, if big bangs are hereditary, what's stopping natural selection to act upon them?

Mostly the fact that universes don't have environments. There is nothing 'outside' the universe that can cull the 'weaker' universes.

Perhaps the universes that have certain properties will just expand forever, and dissapate, with no "Big Crunch" style rebirth (or whatever other mechanism you can postulate). If a "Big Crunch" style event birthed more universes (all with similar, but not quite the same properties from the "imprint" of the last one), then we have our natural selection. After all, natural selection is simply surviving to have more offspring.

Other Comments by Luthien

30. Comment #159026 by shad0w on April 11, 2008 at 11:00 am

REPLY TO : 5. Comment #158599 by troyreynolds86
--------------------------------------

Mathematics on a blackboard pretty much explains everything we see around us.

I would be very very careful confusing mathematical modeling (even speculative modeling) with religious thought which is simply quasi-philosophical garbage.

Equating the two is simply misunderstanding math and science.

Other Comments by shad0w

31. Comment #159090 by pulsar1z on April 11, 2008 at 12:30 pm

I have a theory that the Big Bang is perpetual.

For those who are interested check it out at

www.astronomy.netfirms.com

Other Comments by pulsar1z

32. Comment #159186 by quantum tuba on April 11, 2008 at 2:52 pm

Roger Penrose seems to have been toying with a similar theory recently. However, as he described it, the previous universe did not end in a big crunch but rather reached maximum entropy or heat death. How this could then manifest itself as an exploding singularity is a bit beyond me, but I'm not a theoretical physicist (yet).

Other Comments by quantum tuba

33. Comment #159233 by babrock on April 11, 2008 at 5:37 pm

Yeah,it is still quite speculative, but I am awestruck that somehow we have enuf info to even speculate on anything pre-big bang.

Other Comments by babrock

34. Comment #159241 by babrock on April 11, 2008 at 6:08 pm

AntonAAk
I am no expert on this but, t confusion is caused simply by that, somewhat old, definition of "t universe consiting of everything that exists."
Strictly speaking, t universe consists of everything that exits w/in t three spatial dimensions and one temporal that we are aware of basicly.

Anything that exists outside of these dimensions is outside our universe. All t universes together along w/ ours is called t multiverse or omniverse or something.

That possibly would manage to encompass everything that exits, unless there are somehow multiple multiverses or something.

Personaly, I can only understand another dimension, beyond our three, as something beyond my understanding, but just as we exist in a dimension beyond that of a plan, there is suppossed to be dimensions beyond that of space.

Other Comments by babrock

35. Comment #159242 by Steve Zara on April 11, 2008 at 6:09 pm

Comment #158953 by sidfaiwu

They don't seem to consider that their model for gravity may (one again) be incomplete. There could be small, non-linear gravitational effects that are not observable in the near-field but manifest in the far-field. The effects may even be time-dependent. Thus over time, these far-field effects my decay and cause a deceleration and eventual contraction of the universe.

Of course this is being considered. The problem is that it is far more complex and fiddly than the dark matter idea, which fits observations very well, especially as there are plenty of dark-matter candidates in current supersymmetic theories.

Other Comments by Steve Zara

36. Comment #159261 by scotriani on April 11, 2008 at 7:18 pm

Lee Smolin was one physicist who applied evolutionary science to the universe.

Other Comments by scotriani

37. Comment #159262 by troyreynolds86 on April 11, 2008 at 7:20 pm

Shad0w,

Mathematics may be the language that science is spoken in, yet you seem to have missed the metaphor. Without evidence to either confirm or refute said equations, no matter how elegant the proofs are, we are provided nothing. Zero. Other than more speculation. We can no more assert these claims as having any bearing on reality than can the religious with their assertions. And more danger for us when we do. We are the evidence based community, and we should aways be careful to remain true that that standard or else we fall into the same trap as the religious. That was the point. Math may give us the ability to understand the evidence but it still requires the evidence before it is even a reasonable facsimile of reality.

Troy

Other Comments by troyreynolds86

38. Comment #159286 by b0ltzm0n on April 11, 2008 at 9:26 pm

Hold on! Let me go get my "jump to conclusions mat".

Personally, I'll stick with the good cosmological evidence we have right now for an expanding/accelerating universe. Besides, I bought a nice plot of land on the moon that I plan on retiring to when I'm 120 (that'll be the retirement age by the time I'm eligible). If I'm informed on my 119th birth day that the universe is about to end in a big crunch and our whole universe is going to be a squashed mosaic in the cosmic microwave background of some OTHER universe, I will be very... put.. out.

Other Comments by b0ltzm0n

39. Comment #159611 by robotaholic on April 12, 2008 at 4:02 pm

Well, I'm geekily interested in this because hmm-if you for example remember-after the universe fizzles out to just about nothing after a trillion trillion w/e years - hmm, we can't have absolutely zero degrees kelvin due to violating uncertainty principle (can't know velocity and location both precisely and at absolute zero you would know both)(well WE might not know both obviously lol)so what happens? - mabye I'm bringing something up that is stupid but I've not heard anyone address it pretty much- any ideas?

Other Comments by robotaholic

40. Comment #160613 by sgant on April 14, 2008 at 8:28 am

thought experiment:

if a mass were to achieve light speed would it not also achieve absolute zero (relatively speaking). b/c to an outside observer, time for that mass would have stopped and therefore the atoms in that mass would not be moving (from the observers point of view)?

somebody with some physics background please enlighten me on this.

Other Comments by sgant

41. Comment #198447 by Vaal on June 24, 2008 at 1:38 am

Blimey,

Thought I was joking when I mentioned that Cern might create a black hole and suck us all up, but there is a report shown on the BBC by the European Organization for Nuclear Research investigating if this could occur.

http://news.bbc.co.uk/1/hi/sci/tech/7468966.stm

Lets hope they are right. Sounds like science fiction. Maybe we are going to create a new Universe. What an irony that maybe WE might be God! :-) HaHa!

Steve, what do you reckon? (tongue in cheek)

Other Comments by Vaal

42. Comment #198461 by Oystein Elgaroy on June 24, 2008 at 3:21 am

Comment#198447

The possibility of producing black holes at the LHC is a long shot. For this to happen there must be large (in the sense of being much larger than the Planck length) extra spatial dimensions. They would be smaller than a proton, and have a lifetime of about 10^-26 s. I think there might be greater threats to life on this planet.

Other Comments by Oystein Elgaroy

43. Comment #198463 by Steve Zara on June 24, 2008 at 3:34 am

Comment #198461 by Oystein Elgaroy

I think I vaguely remember something from a Scientific American article a year or two back, which said that black holes produced by the LHC would be unstable even if Hawking Radiation does not occur, and would soon disappear in a burst of particles.

Other Comments by Steve Zara

44. Comment #198467 by Oystein Elgaroy on June 24, 2008 at 4:19 am

Comment#198463 by Steve Zara

That is correct. These black holes would be quantum mechanical objects, and with no conservation laws to protect them they would rapidly decay into other particles.

Other Comments by Oystein Elgaroy

45. Comment #198477 by TeraBrat on June 24, 2008 at 5:41 am

Though I think the evidence is more in favor of "the big freeze" with the discovery of the increasing speed of expansion.

What if they are both right? What if universes do increasingly speed up with expansion and then...

What if two universes collide which sets a contraction in motion that leads to the singularity reforming and a new Big Bang.

Scientists predict that the Milky way is on a collision course with Andromeda. If two galaxies can collide why not two universes?

Just my ramblings, no proof.

Other Comments by TeraBrat

46. Comment #198499 by Oystein Elgaroy on June 24, 2008 at 6:39 am

Comment#198477 by TeraBrat

The following two papers by Aguirre et al. may be of interest to you:

http://arxiv.org/abs/0704.3473
http://arxiv.org/abs/0712.3038

The opening paragraph of section V.C of the second paper is particularly comforting: "Having established that early-time and late-time collisions, as well as the nearly percolating collisions, appear to allow observers to their future in at least some cases,..."

Other Comments by Oystein Elgaroy

47. Comment #198523 by Vaal on June 24, 2008 at 7:50 am

Ouch Oystein

That has hurt my head. Still, at least I learned a new word .. anisotropic.

Edit: So where do I point my telescope to get the lottery results?

Other Comments by Vaal

48. Comment #198533 by Oystein Elgaroy on June 24, 2008 at 8:12 am

Comment#198523 by Vaal

You will find the lottery results written on the teapot orbiting Mars.

Other Comments by Oystein Elgaroy

49. Comment #198720 by Vaal on June 24, 2008 at 11:51 am