[Airthumbs (OP)]

I approach this question based on the fact that supposedly nothing can travel faster then the speed of light. We are informed that as space is expanding faster then the speed of light our visible universe is shrinking. Is it possible our universe is actually the opposite of a Blackhole and instead of matter sucked in, its sucked out?

[yor_on]

That one I'm not sure I'm following?
Do you mean as the expansion grows our 'light sphere' shrinks?

As far as I know it grows, every year we will be able to see one 'light year' further as that light at last have reached us. And that holds true no matter any 'expansion' as far as I know. What the expansion might mean, is that some of the possible light that otherwise would have reached us 'in time' won't though. That as 'space' grows concentrically in every 'point' (possibly) in 'deep space' between the galaxies, and as there is a lot of 'space' out there it might mean that at some point, the light from those furthest away 'galaxies' whatever, might not have a possibility to 'bridge' over the expansion to us.

But our 'light sphere' grows, every second.
As far as I know?

[QuantumClue]

I'm sorry but you will need to rephrase this question better for me. The idiom ''sucked out'' does not make a logical sense.

[Airthumbs (OP)]

Ok, QuantumGlue, I will rephrase the question. Could the edge of our universe be a black hole? A very big one with our universe in the centre...

Yor_on, from listening to the podcast posted on the 25th December I understand that after a billion years or so we will only be able to see our Galaxy.  I think I understood the explanation to be that the universe is expanding faster then the speed of light and that the distances between Galaxies is increasing as a result of this expansion. 
As the Universe is expanding at a rate that exceeds the speed of light in effect it is disappearing from view.

[QuantumClue]

I'll get back to your question. But first, my name is not quantum glue - it is quantum clue. Someone called my quantum cube recently ... ... deep breaths...

[Airthumbs (OP)]

QuantumClue, I apologise for the incorrect pronunciation of your name, I admit it was deliberate, I can't explain what made me do it  []  I hope those deep breathes worked  [] and your input to my question is much appreciated. I suspect that you are very sensative about you name but my dyslexia is obviously no excuse! Or my humour it seems...  [] Does Quantum Glue exist?

[QuantumClue]

It was deliberate?

Again, what did you come here other than  to ''deliberately'' make fun of peoples names?

[QuantumClue]

See Aaron, it is within the magnaminity of the people here to provide a serivice, it is not very welcoming to make fun of their names now, is it?

[yor_on]

Maybe Aaron, maybe it will be so. I don't know, and neither do they. Nobody know what the 'expansion' really is, or even if it exist. We need something to explain why the galaxies are separating so quickly though. And yes, if that happens maybe there will be no more light to reach us. But if so it have to do with the vastness, not that some 'event horizon' is closing in on us. as I see it:)

And QC is Ok, once he's calmed down:)
But names can be a sensitive thing?

Anyway, a black hole? I don't know, I've seen other discussing it as a white hole.

The difference being that with a black hole the 'singularity' lies in the past, but with a white hole its 'singularity' still awaits in the future:)

And if that doesn't hurt your head, you've got a better stomach than me )

[Airthumbs (OP)]

Yor_on, I thought that this was the case hence the reason I said sucked out and not sucked in.  Just one more extension on my question if you please. Is there anyway of knowing if our universe actually exists as a singularity and that in fact the Universe is actually evaporating through the concept of Hawking Radiation?  As the universe becomes less dense it expands?

[Geezer]

See Aaron, it is within the magnaminity of the people here to provide a serivice, it is not very welcoming to make fun of their names now, is it?

Well, you could always retaliate with comments like "Keep your hair on Thomas", but I suppose that would not be terribly scientific, nor would I be able to condone your actions.

[yor_on]

Phieew, you like the difficult ones don't you:)

Don't know, assuming that we are in such a thing we would see 'space' as being very big, in a black hole of sufficient mass/size probably 'limitless', and the Event horizon wouldn't be 'noticeable' anyway, as I think of it at least?

If we were it wouldn't really matter to us, the only thing it might prove is that there can be a he* of a lot of different 'SpaceTimes' out there. And as we too have 'black holes' you might assume that they all then could be connected. And that's okay as the ideas we have of distance probably is purely 'local' if you believe that Lorentz contraction is a 'physical thing' which I do. The other way to see it is to assume that it is a 'rotation' in space, fooling us, but I don't expect that to be true myself. Take a look here http://www.washingtonpost.com/wp-dyn/content/article/2010/08/23/AR2010082303622.html [Links inactive - To make links active and clickable, login or click here to register]

[yor_on]

What you might argue inside such a universe is that we should see light follow certain trajectories as they all should be bound for its 'center'.

[Airthumbs (OP)]

Thanks for the link to the article yor_on, I found it very interesting although I still have problems trying to grasp some of the more technical issues involving equations that seem well  []

With regards to your comment and, I apologise as I just cannot grasp how to use this quote thing, so cut and paste for now...What you might argue inside such a universe is that we should see light follow certain trajectories as they all should be bound for its 'center'.... If we are in the opposite of a black hole then all light will eventually head for the so called event horizon and that's exactly what it does do as in this case the centre is the edge! My heads going to explode soon  [xx(]

Geezer.... I wish I could keep my hair on! But if enough people tell me too it might have a placebo effect so go for it  [B)]

[yor_on]

Ah yes, you're thinking of a 'white hole' and I was thinking of that 'black one'
But shouldn't light have a 'trajectory' in such a one too. A tendency to 'bend' sort of, as seen from us? Even if it might move in the oposite 'direction'?
==

The reason being, as i see it that you then should have different 'gravity' the closer you are to the 'origin' as a 'white hole' should be an infinite 'energy pool' radiating outwards. But I don't know, it's only speculations. And if we assume one to spin, like our black holes do then you might expect frame dragging to add to the effect too?

[Bill S]

What we are looking at here seems similar to the concept of the “gravastar”, sensu Mazur and Chapline.  Their theory suggests that our Universe might exist inside one of these.


 So, what is a gravastar?   The name is derived from the words Gravitational Vacuum Star.  The simplest (perhaps over-simple) answer to this is that a gravastar is a black hole within which not everything is crushed into an “infinitely” small space, or even into a super-heavyweight micro-speck.    In a nutshell, a gravastar, according to Mazur and Chapline, is formed when an exceptionally large star nears the end of its life and starts to collapse under its own gravity.  During this process it reaches a critical density at which its matter is converted into energy which gives rise to a fiery boundary layer.  This is the gravastar.  From outside its appearance will be that of an enormous star.  Further collapse will be prevented because, its authors state, the gravity of spacetime inside the boundary will be repulsive.

Ref. Chapline. G & Mazur P.  “Tommy Gold Revisited”.  www. Arxiv/astro.ph/

[yor_on]

Wow that was a cool one Bill, never mind if it might be disproved. It's still a very imaginative concept, and quite fascinating. I would love to do a book on that one, a fiery SF or fantasy, maybe someone already have?

Really nice.

[QuantumClue]

I really should try and give this some justice. My arguements so far as only associated the no boundary proposal on relativistic concepts.

Relativity is a classical theory at best, whatever makes relativity unified with quantum mechanics does not necesserily need to refer to a logical paradigm. Concepts like string theory is an open interpretation which can either fit into that paradigm in reality or not. Simplicity Einstein once said, in one way or another, is the way physics should be approached. Theories like string theory do not compel to appreciate this line of thought. Relativity is incomplete, but how incomplete depends if simplicity really does loose its train of thought when the estranged quantum world is taken into appreciation. Already reality has been summed up in some of the strangest concepts known to man, born out of mathematical physics.

[CPT ArkAngel]

I could not agree more QC. Well thought and well written...

[yor_on]

Yeah, it's true physics is magic, with a pen, ah, computer?
Anyway, it's the best game in town.

Who said brain?
"Don't need no stinkin **"