Reach the End of Universe: Is There a Wall?

Thread starter david90
Start date Mar 13, 2005
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The discussion centers on the concept of whether the universe has an "end" or a "wall." Participants argue that if the universe is finite, it could wrap around itself, similar to a donut, and that there may be no physical barrier at the edge. The analogy of ancient sailors fearing the edge of the Earth is used to illustrate misconceptions about boundaries in the universe. The conversation also touches on the expanding nature of the universe and the idea of a cosmological event horizon, which serves as an observational limit rather than a physical wall. Ultimately, the consensus leans towards the idea that there is no definitive wall at the end of the universe.

Mar 27, 2005

misskitty

selfAdjoint said:

On the "Strings, Branes, and LQG" forum we are discussing a couple of papers that suggest our observable universe is in the interior of a huge bubble, the expanded result of some fluctuation when the whole universe was small, and that is why we have a nearly flat universe (omega ~ 1), but our mass and dark matter together only come up to an omega of 0.27. The missing .73 has been attributed to "dark energy", but these papers suggest that in the bubble interior, our matter is depleted, only 27% of what it is on the average in the whole universe, so both the omega ~ 1 and our 27% are explained as a special case without positing any dark energy.

So in this picture there would be an expanding "wall", the surface of the bubble, but what it would separate us form is just the rest of the universe.

Interior of a bubble huh?

Ok, I can see that (kinda have to when it comes to physics and the universe

). Where did the bubble theory come from. My computer is very tempramental when it comes to links. So I didn't ge to see the papers you were talking about.

Not to be a pain or anything, but could someone please explain the Dark Matter concept? Someone, I don't remember who, tried to explain it, but unfortunatly I didn't comprehend it as well as I previously though. :redface: