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[Il Palazzo]

"The Great Attractor" isn't bad either, but I'd stick to "Spaghettification" for an astronomy-derived band name.

[MrWiggles]

Did we ever find out where those gravitons (or whatever I'm thinking of) that appear to pop in and out of existence go? I believe I saw a Nova on it, and that was one of the reasons they made particle colliders.

Nope, Gravitons and the Higgs Bosson which spawns them have not been observed yet. This is, believe it or not, an exciting moment in particle physics. Which has been stagnant for almost 30 years.

[cowofdoom78963]

Yeah, but since it's an elephant, it's going to be trampling around, making a big ruckus.


We were looking for a visible elephant (well not really looking per-se, but whatever), we didn't think to listen for it.

Yeah well, if the elephant was really far away you wouldn't be able to hear it.

[Rakonas]

If we can see the beginning of the big bang with telescopes.. would it not be the case that the matter we're standing on moved far faster than the speed of light, or existed from before the big bang, or that everything we know is a misconception? I feel that we really know nothing about the universe, our science akin to a 5 year old trying to wrap their mind around concepts and thoughts that even most adults cannot comprehend...

[Realmfighter]

I think it was emissions from the Big Bang.

[Bauglir]

-snip-

[MrWiggles]

If we can see the beginning of the big bang with telescopes.. would it not be the case that the matter we're standing on moved far faster than the speed of light, or existed from before the big bang, or that everything we know is a misconception? I feel that we really know nothing about the universe, our science akin to a 5 year old trying to wrap their mind around concepts and thoughts that even most adults cannot comprehend...

Speed of Light can't be achieved or exceeded for items with mass.

Anything that existed before the big bang doesn't matter, as it doesn't exist now. The big bang, is a universe rewrite. Each time it happens, it replaces everything.

It also doesn't matter if what we know today is a misconception. Science Academia and knowledge allows for itself to be changed given new understanding, and observations. What we know today is our best understanding, and from what we know, does the best job at explaining what we see, and gives up applications that we use, as well as provide prediction for future events.
Therefore it can be relied on with confidence.

Some Theories are more strong then others. Evolution via Natural Selection is pretty solid. Germ Propagation of Disease is pretty solid. Tectonic Plate Theory is pretty solid. Ect ect ect.

Whereas some theories, such as the Nebula Star Formation Theory have some fairly glaring holes in it. For instance, it can't properly explain the formation of binary star system, the most common solar system.

And theories get replaced, once a better understanding is broached. Einsteins theories replaced Newtons theories, ect.

[Il Palazzo]

Now, there are some weird inconsistencies in what I just said (basically boiling down to how, if at all, the speed of light interacts with expanding space), I think, but I don't have the background to resolve them except to say that their effects are probably small enough that you're really looking at a few seconds AFTER the Big Bang, at a guess. I don't know, precisely. Anyway, that's the gist.

To be precise, we can only ever see as far back in time as about 300-ish thousand years after the Big Bang, as before that time, the matter in the universe was opaque to radiation.
As for the space expansion and speed of light - as far as I can recollect, the observations of distant quasars show that their redshift is such that they appear to be "moving" away from us faster than the speed of light. This doesn't seem to invalidate the postulates of Special Relativity about c being the greatest speed attainable, as these far away objects recede so quickly due to the space between us and them being stretched, and not traveling through space as such.

[MrWiggles]

That has to do more with the c being variable in its media. The stretched space of the 14 or so billion light year away star light is moving faster then the light presented in our more defense 'space'.

[Il Palazzo]

Please explain how is the variability of c in a medium relevant to the subject? I completely missed your point.

[Soadreqm]

One can imagine the universe as the expanding baloon(as EarthquakeDamage described), or expanding dough(space) with raisins(matter) embedded within, with Big Bang being the moment when the baloon(dough+raisins) "appeared" and begun expanding.

Wait, you're saying that space has EDGES? Rather than the universe being infinite, there is a very large but limited space that wraps around? That is so messed up, man. ._.

Wait, is the expansion affected in any way by what's in the universe? If you have some galaxies doodled in pen on a surface of a balloon you're filling, they're just decoration and have no effect on the space stretching. But in the real world, gravity warps space, right?

[Il Palazzo]

Look, the balloon is just a thought experiment for helping to understand what the bing bang, and the expansion of the universe looks like. Or rather what it doesn't look like(i.e.explosion). It's by no means "the" definitive, proper model of the universe.

As for the actual "shape" of the universe:

Spoiler:  Quote from: http://curious.astro.cornell.edu/question.php?number=62 (click to show/hide)

Q: I have read most of the popularizations of physics and astronomy Hawkings, Weinberg, ect. The big bang is often explained using the image of a two dimensional universe (surface of a balloon) expanding in three dimensions. I read once that our universe is a "three dimension surface of a four dimensional balloon" or maybe orange, I don't recall for sure. Is this correct? I realize that 4 and up dimensional spaces can be described mathematically although we can't really imagine them. To the extent possible, I would like to know the "shape" of the universe.

A: Most astronomers would like to know the shape of the universe too! There are three general possibilities. First, like your balloon, the universe might have what we call positive curvature, like a sphere. In this case, which we call a "closed" universe, the universe would be finite in size but without a boundary, just like the balloon. In a closed universe, you could, in principle, fly a spaceship far enough in one direction and get back to where you started from. Closed universes are also closed in time: they eventually stop expanding, then contract in a "Big Crunch." All the geometry that is true on a sphere is also true in a closed unvierse: parallel lines eventually converge (e.g. longitude lines are parallel at the equator, but converge at the poles), large triangles have more than 180 degrees, etc.

The second possibility is that the universe is flat. This kind of universe you can imagine by cutting out a piece of your baloon material and stretching it with your hands. The surface of the material is flat, not curved, but you can expand and contract it by tugging on either end. Flat universes are infinite in spatial extent, and have no boundaries. Parallel lines are always parallel and triangles always have 180 degrees. Flat universes expand forever, but the expansion rate approaches zero.

Finally, the universe might be "open," or have negative curvature. Such universes are sort of saddle-shaped. They are also infinite and unbounded. Parellel lines eventually diverge, and triangles have less than 180 degrees. Open universes expand forever, with the expansion rate never approaching zero.

What determines the shape of the universe is its density (and the Cosmological Constant, a sort of anti-gravity force allowed by General Relativity). It is difficult to figure out what the density of the universe actually is, but it seems that the universe is probably flat