Pulsating universe theory

Jeez, tough crowd

I haven't read all the replies, but the theory I am aware of about the contracting-expanding-contracting universe is where right now we are inside a giant black hole where the even horizon contains the whole universe, so no, you could never escape

This is possible because the larger the sphere, the less dense it is required to be for it to be a black hole. For instance, you could have a density of 1 atom per cubic light-year, but as long as this is true for a big enough sphericall volume, you have a black hole. I think.

[Piz0wn0reD!!!!!!]

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Jeez, tough crowd

I haven't read all the replies, but the theory I am aware of about the contracting-expanding-contracting universe is where right now we are inside a giant black hole where the even horizon contains the whole universe, so no, you could never escape

This is possible because the larger the sphere, the less dense it is required to be for it to be a black hole. For instance, you could have a density of 1 atom per cubic light-year, but as long as this is true for a big enough sphericall volume, you have a black hole. I think.

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that sounds very interesting. got any links?

[RevAgain]

I don't think anyone has made the point that it's impossible because space and time are a function of our universe. The universe isn't moving into empty space as it expands, it's creating that space. It is not a vacuum outside of the universe, we can't power our way out of spacetime.

You'll have to go looking for wormholes into other universes or dimensions to escape that big crunch if it comes I'm afraid.

[Piz0wn0reD!!!!!!]

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I don't think anyone has made the point that it's impossible because space and time are a function of our universe. The universe isn't moving into empty space as it expands, it's creating that space. It is not a vacuum outside of the universe, we can't power our way out of spacetime.

You'll have to go looking for wormholes into other universes or dimensions to escape that big crunch if it comes I'm afraid.

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im dont think that we know this for sure. Also i think someone said that already.

[benkahuna]

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Some drinks got me thinking...

Assuming the universe will eventually colapse on itself and do the big bang thing over and over again:

Could we escape this fate w/ a spaceship? Could we have enough power to fly "out" of the universe and escape its gravity? If so what would happen to the universe? Would it be just short of the matter required to do its thang?

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No. Nowhere to go and the forces would be so powerful you could not escape their wrath. It's much more powerful than an aluminum can crusher. It doesn't matter how drunk you are!

Other guy mentioned wormholes to another universe. Yep, that's pretty much your only hope based on what we've guessed.

Without reading the thread further and thinking how I would do it too.,....I would certainly be able to know when the reverse effect would start...hence I would know when to start putting energy into just staying at my point or getting further. I would just start my rocket ship the second the universe start collapsing...its gonna catch up soon enough.

No links I'm afraid, I can't remember where I heard the idea that the Universe could be inside a giant event horizon, and hence we will eventually collaspe into a singularity. At the time I thought "meh, whatever"

But then I learned a bit of physics which can explain it a bit. The radius of an event horizon is:

r = d * M

where d is just a constant (happens to be 2G/c^2, G the gravitational constant, c the speed of light) and M is the mass inside the black hole

You could say that if you had a mass M uniformally distributed inside a sphere of radius r, this will become/is a black hole if M>r/d

so, suppose you had some material of denisity p

The if you filled up a sphere with this material the mass inside would be density*volume, which would be:

M = p*(4/3*pi*r^3)

p = density, pi = 3.141...

so, the requirement for a black hole to exist is as said before

M>r/d

but we know M, so the requirement is:

p*4/3*pi*r^3>r/d

and with some algebra, the requirement becomes:

r>(4/3*p*pi*d)^(-1/2)

the right hand side will just be a constant, since p and pi and d are all constants, and it will always be finite as long as p>0 (meaning the material is not massles)

so what this shows is, as long as you make your 'r' big enough, which means make your sphere big enough, you have a black hole

so basically the argument is if the universe is big enough and is close enough to being uniformly distributed, we may be inside a giant black hole

I'm guessing there are several complications in the real world, for example the fact that mass is moving, but that's the general idea

[xniNja]

This is, in fact, ridiculous. You can ignore me if you like, but if you don't define universe as specifically different than universe, then it is "one" existence. By definition you cannot escape the one universe, as your existence is defined within it.

Now, let's assume for a moment there are more universes, to the extreme, infinite...

Could a "wormhole" lead to an alternate universe?

Yes, there could also be "heaven" on the other end, unicorns, leprechauns, 1942, and Michael Jackson's neverland.

My argument is that all of them are equally probable.

[tek]

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Actually I should have written "dark energy" in place of dark matter. Two different things. My bad.

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Is this dark energy the same as 'nothingness' that zen people talk about?

[Piz0wn0reD!!!!!!]

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This is, in fact, ridiculous. You can ignore me if you like, but if you don't define universe as specifically different than universe, then it is "one" existence. By definition you cannot escape the one universe, as your existence is defined within it.

Now, let's assume for a moment there are more universes, to the extreme, infinite...

Could a "wormhole" lead to an alternate universe?

Yes, there could also be "heaven" on the other end, unicorns, leprechauns, 1942, and Michael Jackson's neverland.

My argument is that all of them are equally probable.

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why would i ignore you?