The infinite space of the Universe

As more time goes by where they do not find the Higgs, the stronger the evidence becomes that something is wrong with the Standard Model - the LHC should almost certainly find it if it exists in way we think it exists. If we don't find it, something is wrong with our understanding of the SM, and this will push research into other areas which may well provide a route towards Grand Unification and eventually a Theory of Everything.If we find the Higgs, we just cheer and say - yep, thought so. It doesn't actually advance us very much. This is the problem when experiment is lagging so far behind theory. If the SSC had come on line as expected, god knows where we would be by now...

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Would that be Rob Mann?

It isn't any proerty of the bar - it is the property of the space in which the bar resides.

Weld? No, of coures not. Where does this come from? Yes, in exactly the same way that if you travel 21599 miles around the Earth, you will be stretched out and bent back all across the Earth to where your journey began.

If you travel in a perfectly straight line in a random direction and travel 21600 miles (+/- a bit to counter the oblateness) then where do you think you'll end up??? I'm sorry, I'm not sure what you mean. If the Universe were to stop expanding, and if you travelled far enough (it's a hell of a lot further than 80 billion light years - probably >> 80 trillion light years) in a straight line, you could return to your starting point. This is basic cosmology.

Hmmm... I make it 4.81 billion times more massive

No Buzz, you are talking about your own infinitesimal experience of reality. Are you really so naive as to think that what you perceive as the 'the way things are' in your small area of life is somehow not just slightly applicable to the Universe at large, but is sufficiently all-encompassing that it gives you the ability to declare false that which scientists, who have dedicated their lives to the subject, suggest is true? Grow up! (what is it about old dogs and new tricks?)Perhaps you'd like to give me a definition of 'perfectly straight'? Buz, you really need to check that reading comprehension - or the glasses. No-one has said that this is how the Universe behaves - this is how the Universe behaves *IF* it is closed, and *IF* the expansion were to halt so that we can talk about this particular property. And how the Universe behaves has nothing to do with steel bars or any other such object.Edited by cavediver, : No reason given.Edited by cavediver, : No reason given.Edited by cavediver, : No reason given.

No Buz, we use 2d analogies and pictures for idiots like you who haven't a hope in hell in understandiong anything mroe complex - and in your case even these simpleton analogies just fly by several miles above your head. We work in the real four dimensions of space-time. Do you really think that real cosmology progresses by us thinking about ants on balloons??? Perhaps SG and I should just start discussing all of this in the real language of the subject - at least we wouldn't have to be bothered by such idiotic comments.

Buzz, if I ask for a definition of straight, replying not-curved is not particularly helpful.Look, I'm sorry, but as with ICANT, it is pointless trying to argue this with you. You know NOTHING about the subject yet you are deluded to the point of feeling adequately empowered to argue with experts. The points have been made sufficiently well and sufficiently clearly for everyone else reading this, so continuing is just a complete waste of everyone's time. If you don't get this now, you never will.To anyone else - if you have a question reagrding any of this, please feel free to ask.

Hmmmmmmmmmmmm... I don't really like this concept. It's sort of the standard impression of GR, but it's lopsided with respect to the treatment of gravity cf matter - we have a field theory of gravitation but sill thinking of matter as blobs. Furthermore, it gives the horrific impression that space stops at the boundary of your matter blob, and then starts again on the other side - probably why I never liked the Vaidya metric The first step to rectifying this is picturing the matter (and gauge) fields stretched over space-time. So matter certainly no longer occupies space-time - the space-time merely provides a background chart that enables the concept of location to be applied to the field excitations (the blobs). This is at the level of my favourite anaology (2d of course to delight Buz and ICANT), where we picture matter as waves on the background of an ocean of space-time.But this picture is still missing the vital point - there is no 'space' in space-time. This is simply an illusion of the coupling the metric field. Space-time has a fundemental topology but its geometry is purely a derived, *emergent* property of the behaviour of the metric. Andromeda is only .5 million times further away than Proxima C. by virtue of some values in a field. The 'distance' is purely an illusion that we ourselves generate by 'perceiving' the Universe. Not to take anything away from our dear departed Douglas, but space - even if infinite - is really, really small And without conciousness to give it some impression of size, there really isn't that much to it all Actually, it was my first steps in String Theory that made me realise this. Not that it requires ST but when you interpret the terms of the Polyakov Action from the perspective of it being simply a 2d theory with no *prior* thought of a target space, it becomes obvious.Edited by cavediver, : No reason given.Edited by cavediver, : No reason given.Edited by cavediver, : No reason given.

Easy - how many rational numbers (fractions) are there between the integers 1 and 2?

Yep, Buz has finally raised himself above Einstein, Feynman, Hawking... what it must be to have a mind of Buz' calibre.

The first photons emitted were immediately re-absorbed. The early Universe was extremely dense and there was no free path through space for photons to travel. Even thousand of years after the Big Bang, temperatures were suffciently high that eletrons and hydrogen/helium nuclei were not combined into neutral atoms, but existed as a plasma of charged particles. This plasma was opaque to photons. About 400,000 years after the Big Bang, temperatures cooled sufficiently that the electrons and nuclei boudn together to form neutral atoms of hydrogen and helium. This period is known as recombination. For the first time in the Universe's history, it was transparent to photons. The photons from that period formed the all important cosmic microwave background radiation (CMBR) Those photons are still travelling through the Universe. Space has no boundary - it is either infinite, compactified back onto itself, or possibly smoothly bleeds at the edges into the higher dimensional 'bulk' space.

Don't worry about it - it was an oblique comment from one cosmologist to another concerning the possibly ephemeral nature of distance.