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Author Topic: How come our universe still exists?  (Read 1905 times)

Offline Railton2

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How come our universe still exists?
« on: 24/02/2011 14:31:47 »
I am not sure where to post this thread. Sorry if it is the wrong place. If it is, please move it to the correct forum, thanks in advance :D
 

Hey

 
How come our universe still exists?

According to what I know our universe was created from a singularity, the big bang, a so called explosion. If everything, including all matter and energy, was created at the time of the big bang, then all matter must have been squeezed together in the first nanoseconds of our universe. How come that there wasn't a black hole, when all the matter from our universe was squeezed into that small place in the first second?

If there was a black hole, how come our universe still exists?


According to what I know, the definition of a black hole is an object so dense, that the gravity is so powerful, that not even light can escape. That means in order for matter to escape from the event horizon created by a black hole, then the matter MUST exceed the speed of light. According to Einstein's theory of relativity; In order for matter to travel faster than the speed of light, then you must need more than an infinity amount of energy. Then how come that the matter escaped from the event horizon at the beginning?
All matter in our universe MUST have travelled faster than the speed of light in order to escape it. Does that mean that all the matter in our universe had more than an infinity amount of energy in the beginning, in order to escape?

Why didn't the universe collapse by its own gravity, without using an infinitive amount of energy for the matter to escape?
If there wasn't an infinity amount of energy at that time, then our universe must have collapsed by its own gravity or what?


How come our universe still exists?

Did our universe collapse by it's own gravity?
Could our universe be a black hole?




Thanks for reading, I really hope you understand and will answer my questions :D

Sincerely,
Mark


Have a great day!


 

Offline Soul Surfer

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How come our universe still exists?
« Reply #1 on: 24/02/2011 14:49:03 »
This is a very valid question if you think that our universe originated in an explosion.  But it didn't  "The Big Bang" was a facetious name created for the cosmology by people who preferred the "continuous creation" cosmological hypothesis.  However it stuck even after continuous creation had been proved to be incorrect.

What really happened was not an explosion but space expanding to increase the separation between everything in the universe.  Gravity has now dominated this expansion at all scales up to great clusters of galaxies and it is only at the very largest scales that this expansion of space can be seen.  On the whole very little of the material in the universe is moving very fast,  That is at speeds relative to the microwave background radiation of more than 1000km/s.

As for whether we are inside a black hole,  that is a much more difficult question subject to argument.  Many experts say no but a few say maybe and I tend to agree with them.
« Last Edit: 24/02/2011 14:51:44 by Soul Surfer »
 

Offline Pikaia

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How come our universe still exists?
« Reply #2 on: 24/02/2011 16:35:38 »
The universe is nothing like a black hole. Both have virtually infinite density, but a black hole has zero size and infinite duration, the big bang had zero duration but infinite size, extending throughout the (infinite) universe.

There is no infinite speed, as soul surfer says everything is more or less at rest relative to the surrounding space, it is the space between objects which expands. A hard concept to swallow, but that is what the science says.
 

Offline abacus9900

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How come our universe still exists?
« Reply #3 on: 27/02/2011 11:59:44 »
Some scientists have put forward the idea that our universe is but one universe in a 'multiverse', a bit like floating 'bubbles', and that our particular universe may have been the collision of two or more 'bubble' universes. These different universes would have their own special laws of physics, if true, and be nothing like our one. This may have been going on for eternity, perhaps one day we will know. But eventually all the energy in the universe will become so spread out an disorganised that it won't really be a universe any more.
 

Offline Bill S

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How come our universe still exists?
« Reply #4 on: 28/02/2011 19:30:17 »
This is exactly the sort of question that, I think, should be asked and answered by authors of P S books.  As a non-scientist, I am not going to try to answer it, but here are a few thoughts.

Quote
the definition of a black hole is an object so dense, that the gravity is so powerful, that not even light can escape.

True, but some scientists seem to think that a B H may lead to a white hole, through which matter and energy could escape; in this model spacetime would be expanding from a W H. 

Quote
Then how come that the matter escaped from the event horizon at the beginning?

If there had been an event horizon at the point of the B B, the Universe could still be inside it.  It might be interesting to compare this idea with the “gravastar” theory of Pawel Mazur, George Chapline.

Quote from: Pikaia
a black hole has …………infinite duration

Not according to Hawking.

Quote from: abacus
eventually all the energy in the universe will become so spread out an disorganised that it won't really be a universe any more.

As the galaxy groups move further apart, would gravity within the groups not tend to pull the groups closer together, so the Universe would simply become a collection of more widely spaced galaxy groups?
 

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How come our universe still exists?
« Reply #4 on: 28/02/2011 19:30:17 »

 

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