ElDiablo wrote:A little rambling...
The subject in general is mind-blowing and awe-inspiring. I can't help but think of this in 3d and the universe being contained in some way. But there may be no edges, we could just be part of a Celtic loop where everything that's part of the loop is unstable and that which is not the loop is stable. Instability creates universes and stability is nothing. What we detect at the quantum level may be a transition. The multi-dimensions that string theorists talk about may be different expressions of that instability.

If anything this shows I don't know anything, but that's not the same as nothing.

Ironclad wrote:Excuse my ignorance once again.

BB happens, and the photons get 'ejected' (I know, I know), so how comes GWs can affect/spin these particles that are, presumably, moving faster?

I'm an idiot, I suspect.

lpetrich wrote:Jester blogs on this finding: RÉSONAANCES: Curly impressions

"If this holds" is the central question now. This sort of experiments is difficult and subject to pesky instrumental effects and systematic effects due to foreground emission. It's not impossible that BICEP screwed up; in fact, experts point out some worrying aspects of the data, for example the excess in the BB spectrum at high multipoles. So I would say at this point it's fifty-fifty. Fortunately, there are many experiments out there with similar sensitivity (Planck, ACTPole, SPT, POLARBEAR) that should be able to confirm or refute the claim in the near future. In particular, the release of Planck polarization data this year should straighten many things out.

However, this point was addressed by the BICEP2 folks in their presentation. Their view is that (1) the high data points are not very statistically significantly high, and (2) with new data that they haven't released from their third-generation experiment, they don't see the same effect. So this is presumably what gives them confidence that the excess is a temporary, statistical fluke that will go away when they have more data.

Katherine wrote:I say 'Checkmate, Creationists' on Twitter, someone replies with this:

lol yes Science closer to proving Genesis, an always existing universe would have dealt a fatal blow

??????????????

The person seems to have issues with atheists, and she particularly seems to revel in stirring up shit with Prof Brian Cox.

kennyc wrote:

ElDiablo wrote:A little rambling...
The subject in general is mind-blowing and awe-inspiring. I can't help but think of this in 3d and the universe being contained in some way. But there may be no edges, we could just be part of a Celtic loop where everything that's part of the loop is unstable and that which is not the loop is stable. Instability creates universes and stability is nothing. What we detect at the quantum level may be a transition. The multi-dimensions that string theorists talk about may be different expressions of that instability.

If anything this shows I don't know anything, but that's not the same as nothing.

The Doughnut Theory of the universe, AKA the Homer Simpson Model

http://en.wikipedia.org/wiki/Doughnut_t ... e_universe

hackenslash wrote:
Our 3-brane is separated from another 3-brane by an additional dimension of space. The Big Bang occurred when these
two 3-branes slammed together. There is, in this model, another cosmos, much like ours, residing on the other brane
Since gravitons can travel between branes, we feel the gravity of the matter on the other brane but, because photons
can't travel between branes, it doesn't react electromagnetically in our cosmos, so we can't actually see it anywhere
in the electromagnetic spectrum - dark matter

Calilasseia wrote:

Reeve wrote:I wonder if this will make Roger Penrose's cosmological model more testable. I seem to remember that his cyclic one was crucially dependent on gravitational waves with the predictions it made.

Ditto for Steinhardt & Turok's model.

Stephen Hawking claims victory in gravitational wave bet

Stephen Hawking has claimed victory in a bet with a fellow scientist over the discovery of primordial gravitational waves, ripples in the structure of space-time from the birth of the universe.

The Cambridge cosmologist bet Neil Turok, director of the Perimeter Institute in Canada, that gravitational waves from the first fleeting moments after the big bang would be detected.

Speaking on BBC Radio 4's Today programme, Hawking said the discovery of gravitational waves, announced on Monday by researchers at the Harvard-Smithsonian Centre for Astrophysics, disproves Turok's theory that the universe cycles endlessly from one big bang to another.

If confirmed by other groups, the discovery would count as the strongest evidence yet for cosmic inflation, a theory which says that the universe went through a period of extremely rapid expansion soon after the big bang. The theory explains why the universe looks almost the same in every direction.

"It is another confirmation of inflation," Hawking told the Today programme. "It also means I win a bet with Neil Turok, director of the Perimeter Institute in Canada, for cyclic universe theory predicts no gravitational waves from the early universe."

But Turok was not ready to concede just yet. He told the programme that the bet rested on results from the European Space Agency's Planck space telescope, which last year failed to spot any signs of gravitational waves.

continues: http://www.theguardian.com/science/2014/mar/18/stephen-hawking-gravitational-wave-bet-big-bang

surreptitious57 wrote:If branes exist in spacetime then it must have existed before the Big Bang otherwise it could never have happened.

They must be incredibly unstable if their collision results in the creation of an entire Universe.

Could dark energy therefore be the result of that collision ? That would explain why the Universe is still expanding.

Dark matter could be undetected matter from the collision also.

If inflation falsifies this then we now know what the other ninety six per cent of the Universe is composed of.

Though other Universes shall remain immune to detection. Though if this one keeps expanding at the rate it does then local space will at some point be devoid of virtually all light because the only visible star will be the Sun. And all of this from a single physical reaction over thirteen billion years ago. It is therefore not too grand a statement to say we owe our very existence to quantum mechanics

I remember watching a BBC Four documentary last year about explanations for the origins of the Universe [ the one where Lee Smolin and Roger Penrose and Neil Turok were each given a Rubik Cube to solve ] and the brane collision was one model on the table. Now with falsification someone should get a Nobel because it is that significant.

I think it would be very unfair for it not to go to Andrei Linde as it was he who originally suggested it.

And this coming so soon after the discovery of the Higgs two years ago. Which is very unusual indeed now as the Universe does not usually give up its secrets that frequently So anyone who is a physicist or has an interest in physics is very fortunate indeed to be living in these times. I for one shall definitely be trying to learn more about it and specifically cosmology in light of this fantastic discovery

Pulsar wrote:

Calilasseia wrote:

Reeve wrote:I wonder if this will make Roger Penrose's cosmological model more testable. I seem to remember that his cyclic one was crucially dependent on gravitational waves with the predictions it made.

Ditto for Steinhardt & Turok's model.

Stephen Hawking claims victory in gravitational wave bet

Stephen Hawking has claimed victory in a bet with a fellow scientist over the discovery of primordial gravitational waves, ripples in the structure of space-time from the birth of the universe.

The Cambridge cosmologist bet Neil Turok, director of the Perimeter Institute in Canada, that gravitational waves from the first fleeting moments after the big bang would be detected.

Speaking on BBC Radio 4's Today programme, Hawking said the discovery of gravitational waves, announced on Monday by researchers at the Harvard-Smithsonian Centre for Astrophysics, disproves Turok's theory that the universe cycles endlessly from one big bang to another.

If confirmed by other groups, the discovery would count as the strongest evidence yet for cosmic inflation, a theory which says that the universe went through a period of extremely rapid expansion soon after the big bang. The theory explains why the universe looks almost the same in every direction.

"It is another confirmation of inflation," Hawking told the Today programme. "It also means I win a bet with Neil Turok, director of the Perimeter Institute in Canada, for cyclic universe theory predicts no gravitational waves from the early universe."

But Turok was not ready to concede just yet. He told the programme that the bet rested on results from the European Space Agency's Planck space telescope, which last year failed to spot any signs of gravitational waves.

continues: http://www.theguardian.com/science/2014/mar/18/stephen-hawking-gravitational-wave-bet-big-bang

surreptitious57 wrote:Even if branes exist on spacetime as opposed to in it then it still would have to exist before the Big Bang.

Though that would not necessarily be true if there are other models so maybe it is too early to say at this point in time ?

Dark energy certainly has the properties of repulsive gravity but does that automatically mean that is what it is ? There must be alternative explanations otherwise why not regard it as such ?

If light is impervious to branes then it is entirely possible for dark matter to be a result of brane collision as it is impervious to it too