The infinite space of the Universe

Is the universe considered infinite as such?I thought current cosmological modls suggested that if you went in one direction fast enough (i.e. >>C), for long enough then you would eventually end up back where you started?This was my understanding and I am keen to be corrected if this is not the case?

I don't think so. Not unless they were travelling in one direction faster than the rate of expansion, which itself exceeds the speed of light.I could well be completely talking out of my arse here. So I think we need some input from someone who actually has a knowledge of these concepts including the proposed shape of the universe, the rate of expansion and what the speed of light actually means in relation to moving bodies seperated by space in an expanding universe.Cavediver...?
Son Guko...?

Matter is not "expelled". It is not an explosion of matter. It is an "explosion" of space (and time).In other words the space between the matter expands thus the matter seperates. According to inflation theory this occurs incredibly rapidly in the very early universe. Much much much faster than the speed of light. Edited by Straggler, : No reason given.

Space is matter?How so?

So is time matter too?
Or does time not exist?

So is time matter too?
Or does time not exist?

If you would stop making unsubstantiated assertions you might actually say something worthwhile.

Proof? A dictionary definition of a technical word? Are you serious?The predicted empirical results of General Relativity are a much firmer basis on which to base our conception and knowledge of the nature of time.Additionally the increase of entropy, 2nd law of thermodynamics and the "arrow of time" need to be taken into account.Frankly Aqo you are evidently so far out of your depth and so certain in your misapperhensions that I doubt you have anything worthwhile to say on this topic at all.

Hi Walterberns
Welcome to EvC. We have been discussing the issues you raise and related topics in this thread http://EvC Forum: T=0 and a Zero Energy Universe -->EvC Forum: T=0 and a Zero Energy UniverseAlso relevant is the transcript of an Alan Guth lecture that can be found here - http://arxiv.org/PS_cache/astro-ph/pdf/0101/0101507v1.pdfIf you are looking for direct responses to your comments clicking the 'reply' button of the message that you are responding to will notify the person who wrote the message you are responding to.Welcome aboard!

True nothingness is a concept. Not a paradox.
In the everyday world nothingness rarely corresponds to true nothingness and nor does it need to.When we say "There is nothing there" we don't actually mean empty spacetime in day to day use.Anyway there are many things that are concepts that do not strictly exist.
There is no such thing as a "true" circle. It is a mathematical construct. By your definition does that mean circles do not exist in reality? Likewise spheres? Should these terms be removed from dictionaries on the basis that they do not exist?Edited by Straggler, : No reason given.

I am interested.
Where does the weak nuclear force fit into this? Does that have a field presence in the vacuum too? Do all 4 fundamental forces have an ever present field presence in every point of the vacuum?
How does the answer to this relate to a possible theory of everything? How does gravitataion have a field effect in the vacuum of curved spacetime when gravitation is curved spacetime? I am missing something fundamental here as this doesn't make sense to me?

Can you explain further the idea of symmetry breaking? Also the Higgs mechanism and the role of the Higgs Boson?
How are symmetries and laws of conservation related? Does the breaking of a symmetry in this context (the electroweak split) result in the separation of a conservation law? Or is this a complete misunderstanding of the relationship between the two things? If the pre-existing topology is not a result of the fields what defines or shapes this topology? Was this topology something inherent in the BB and thus inevitable for example or did it evolve afterwards as a result of other factors such as energy/mass distribution (for example)?

Oh.
Just out of interest do you really teach such a course?Can you reccommend a decent book that can explain the basis of these concepts without requiring a Phd in maths to get past the first chapter?

Thankyou for your reply. I appreciate your time.I attended(ish) lectures by TW Kibble and Abdus Salaam at college and so desperately wish that I had then realised the opportunity afforded me. If ever there was proof that youth is wasted on the young it is I. From which symmetries are the conservation of spin and color derived? I don't understand the term "Higgs field". I get the concept of the 4 fundamental forces of nature as fields but what is the Higgs field? What role does the Higgs boson play in the Higgs field? Is it the "force carrier" particle? Understood (I think). Thankyou for making this clearer than any previous explanation I have heard. Can you explain how this works in more detail?
What makes it local rather than global?I appreciate that this might be getting to the point where
A) Maths becomes the only meaningful method of describing these things
B) I am completely out of my depth
C) It becomes too time consuming for you to try and explainAs such can you reccommend any books that are of a suitable level that might shed some light on the basics of these topics? I am not mathematically illiterate but rusty is an undertatement. My undergraduate physics course was all too long ago.................

Buz you could of at least tried to answer Lyx2No's question. It is pretty darn relevant.
What is perfectly straight? No deviations from a single direction? No deviations in space?
If the space itself is curved.......... Well you work the rest out for yourself.
However the bar itself remains perfectly straight. The bar itself doesn't need to bend or deviate to reconnect. That is the point.Think of your steel bar as a having a small laser attached at the point where you are holding the bar. This produces a laser beam. A perfectly straight laser beam shining along perfectly parallel to the steel bar just above the surface of the steel bar.
At what point would you expect the paths of the perfectly straight laser and the perfectly straight steel bar to separate? Which one of the two do you consider to be "straight"?Do you see the point?