Potential Evidence of Inflationary Big Bang

[klaus54]

Definitive Evidence of Multiverse!

MSNBC just reported: "... and a pink planet the size of our universe is discovered!"

After the commercial break, it turns out they were only talking about a pink frozen dwarf planet-like object 7 billion miles from our sun (2012VP-113), nicknamed 'Biden'.

A great example of the scientific illiteracy of the general public as a whole and communications majors in particular. "The size of our universe...?" Oh, boy. And "Biden"...

Oh, wait -- this is a joke. Nearly got me!

[robrecht]

A great example of the scientific illiteracy of the general public as a whole and communications majors in particular. "The size of our universe...?" Oh, boy. And "Biden"...

Oh, wait -- this is a joke. Nearly got me!

Actually, it's not a joke. Sad, but not a joke.

[robrecht]

Here's a couple of news reports about the newly discovered dwarf planet:

http://arstechnica.com/science/2014/...earch=100k_pvs

http://www.you-tracker.com/Result/dw...f-5e6153b67388

[Teallaura]

It WAS the size of the universe... back when the universe was just a little verse....



Okay, leaving now...

[firstfloor]

So you think you understand the Big Bang? If the early Universe is super dense, why did it not disappear into a black hole? I have never seen anything that explains this but I think I have an idea of the answer. Any thoughts?

[robrecht]

So you think you understand the Big Bang? If the early Universe is super dense, why did it not disappear into a black hole? I have never seen anything that explains this but I think I have an idea of the answer. Any thoughts?

No I don't think I understand the Big Bang. But I'd be happy to hear your answer.

[robrecht]

... Any thoughts?

My only thoughts about this would be to presume that proponents of some kind of big bang are thinking of some kind of massive impulsion (expulsion, explosion?) or inflation of space that completely overcomes the force of gravity at that point in time, if indeed gravity existed as a force at that point. Just a thought. I'll let those who understand this to speak intelligently about this issue.

[firstfloor]

No I don't think I understand the Big Bang. But I'd be happy to hear your answer.

I think the answer is because there is virtually no gravitational gradient in the early Universe and the Universe has no edge to it. The flattening is what inflation does. It is exceedingly dense but also extremely uniform so every particle is equally attracted in every direction.

[robrecht]

I think the answer is because there is virtually no gravitational gradient in the early Universe and the Universe has no edge to it. The flattening is what inflation does. It is exceedingly dense but also extremely uniform so every particle is equally attracted in every direction.

By 'no edge' do you mean infinitely large or turned in upon itself or something else?

[firstfloor]

By 'no edge' do you mean infinitely large or turned in upon itself or something else?

[robrecht]

Yes, of course, I too think it leaves open the question of the multiverse. But, if this were confirmed, I think I've read that it would exclude some theories of the multiverse, eg, the brane collision theory. Can anyone confirm and explain (for us lay people) why that is?

Apparently some think that this even provides some kind of evidence for a multiverse:

http://www.scientificamerican.com/ar...leFormat=false

HT to Tassman for the link.

[JimL]

I think the answer is because there is virtually no gravitational gradient in the early Universe and the Universe has no edge to it. The flattening is what inflation does. It is exceedingly dense but also extremely uniform so every particle is equally attracted in every direction.

The answer is gravity. Gravity under the right conditions becomes repulsive rather than attractive, hence inflation.

[robrecht]

Bear in mind that I am not expert; only trying to get a grip on what physicists try their best to tell us. ...

Don't worry, it turns out you really don't have to be an expert to understand this stuff:

String theorists discuss fine tuning of the universe, the multiverse, and the five-string banjo

[klaus54]

Just kibitzing my two cents with a very simple example: The surface of sphere, considered as a two real-dimensional manifold, has no "edge".

K54

[sylas]

The answer is gravity. Gravity under the right conditions becomes repulsive rather than attractive, hence inflation.

No, the answer is not gravity. Inflation is not caused by repulsive gravity.

Be that as it may, inflation is fair enough as an answer to the question of why the universe did not collapse into a black hole. But inflation itself is not caused by gravity.