Three models of universe

Main Question or Discussion Point

I know there are three models of the universe: closed, flat and open.
But which one of these models is the most accepted by scientists and why?

I read that the WMAP satellite discovered that the universe is flat. But other observations have shown that, from 7.5 billion years after the Big Bang onwards, the expansion rate of the universe has actually been increasing, concurrent with the Open Universe theory.

This is a little bit confusing to me, so can someone explain?

(maybe there are also other theories, but please just stick to these three in answering my question)

Last edited:

nicksauce
Homework Helper
WMAP7 data finds that the universe is very close to flat, with some possible negative curvature. However, perfect flatness, or positive curvature are not excluded at any significant level.

The accelerated expansion has nothing to do with the universe being open or closed, but rather is the effect of dark energy.

WMAP7 data finds that the universe is very close to flat, with some possible negative curvature. However, perfect flatness, or positive curvature are not excluded at any significant level.

The accelerated expansion has nothing to do with the universe being open or closed, but rather is the effect of dark energy.
But all three of these models started with a Big Bang right?
Can you explain some more? I still don't really get it.

3 models - it was before Dark Energy was discovered.

1. Closed, DE is weak, Universe exists limited time and collapses back. This scenario is known to be false.
2. Closed, DE is strong. Universe starts to expands
3. Flat
4. Open Universe.

Depending on the parameters of DE there are 2 subscenarious fro N2, N3 and N4:
A. infinite inflation
B. Big Rip (phantom energy)

So there are 7 scenarios, 1 is discarded.

But which one of these models is the most accepted by scientists?

There is not enough obvervational data except #1 is not possible.

We know that space is almost flat (so we can't chose between closed, flat or open)
We don't know how density of Dark Energy depends on the age of the Universe, so we don't know if it ends with Big Rip or not.

I once heard a recorded lecture by Alan Watts where he explained the two dominant Myths of Western culture involving the nature of the Universe. He then described a Chinese model of the Universe to contrast the other two. Here is a brief summary of each of the models…

1.) The Ceramic Model – The Universe as artifact.
2.) The Fully-Automatic Model – The Universe as dumb energy and random cause & effect.
3.) The Organic Model – The Universe as organism.