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Old Feb 6th 2016, 02:41 PM   #1
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More problems with big bang

Ok, I have been thinking more carefully about this. I was told that the big bang was an explosion of space rather than an explosion of matter. Here are my current difficulties:

1. If all mass was at some point crammed into space the diameter of an atomic nucleus why then did not the short range nuclear force rule? What over powered the nuclear force to disperse all the matter? I mean surely it couldn't have been the comparatively weaker electromagnetic force.

2. Why would the big bang produce rotating galaxies? Where did the angular momentum come from and why didn't it produce similar amounts of clockwise and anti clockwise angular momentum in roughly normally distributed fashion?
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Old Feb 6th 2016, 06:26 PM   #2
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Remember that mass and energy are not actually different things (E=mc2)
they are just different manifestations of the same thing.
Look at the CERN particle collision pictures, you have particles seeming to appear out of nowhere as gamma rays become particles and particles disappearing as they become gamma rays.
At the big bang, there is no distinction between energy and matter,
it is only when the difference in energy density between different regions gets different enough that any such distinction can start to be made.
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Old Feb 6th 2016, 06:48 PM   #3
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Are you suggesting that all the mass moved out of the singularity by invoking Heisenberg's uncertainty principle?
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Old Feb 6th 2016, 07:02 PM   #4
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I'll take on number 2:

Originally Posted by kiwiheretic View Post
2. Why would the big bang produce rotating galaxies? Where did the angular momentum come from and why didn't it produce similar amounts of clockwise and anti clockwise angular momentum in roughly normally distributed fashion?
I have seen no evidence that there is a net angular momentum of the universe, as measured by looking at the sum of the momentum of the 100 billion or so galaxies. Please share of you have seen any data that says otherwise. Given that best evidence is that a majority of the matter in the universe is dark matter (not stars) - I sincerely doubt that anyone has a good handle on whether there is a net angular momentum or not.
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Old Feb 11th 2016, 01:42 PM   #5
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Nobody Knows

I don't think anyone knows what happens in the singularity,
Distance does not exist (that is inherently the essence of the singularity),
I would suggest that Time does not exist either,
(if there is no change then there is no time, if there is no space there is no change...)
So how does one move from this ridiculous state to an expanding universe?

This is not new a question, it is as old as the big-bang concept itself, but we still do not have a clean answer.
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Old Feb 11th 2016, 05:59 PM   #6
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Originally Posted by kiwiheretic View Post
1. If all mass was at some point crammed into space the diameter of an atomic nucleus why then did not the short range nuclear force rule? What over powered the nuclear force to disperse all the matter? I mean surely it couldn't have been the comparatively weaker electromagnetic force.
You're not taking into account that the universe was far too hot for neutrons to bind together, even when the strong force was acting to keep them together. I.e. simply put, the kinetic energy of the neutrons was far too great to let them bind together.

Originally Posted by kiwiheretic View Post
2. Why would the big bang produce rotating galaxies? Where did the angular momentum come from and why didn't it produce similar amounts of clockwise and anti clockwise angular momentum in roughly normally distributed fashion?
I don't see any reason to assume that there shouldn't be rotating galaxies. Everything was moving about randomly at that time. When the temperature decrease enough for the gravitational force to bring matter together then just by shear numbers there had to be a great deal of matter in which the total didn't have a total angular momentum adding to zero. Consider how it'd work. Two large pieces of matter (e.g. asteroids) were being drawn together by the mutual gravitational force. It'd be statistically unlikely for them to be moving together along the exact same axis. That means that if, for instance, one asteroid was initially at r = (x, y, z) = (0, 0, 0) = 0 and whose initial velocity was along the x-axis then the other one would be initially located at r = (100, 0, 0) and whose initially moving along the x-axis but in the opposite direction as the first one was moving. So although the mutual force as along a mutual axis and will start accelerating towards each other the system had a non-zero angular momentum. Combine this with all the matter in the universe and all moving randomly then it follows that almost all galaxies had to have some angular momentum which implies that they have to be rotating.
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Old Feb 13th 2016, 02:54 AM   #7
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My personal belief is that the "singularity" does (did) not exist...

The big-bang singularity is postulated from an extrapolation of the observation that the (observable) universe is expanding.
However any experimentalist will warn you of the dangers of over-extrapolation.
The theorists will tell you that they can follow the physics back to some pico-seconds or so of the singularity.
This is where the "magic" happens.

I predict that "something" will be discovered that will preclude the formation of the big-bang singularity, I suspect that this same "something" will similarly apply to the singularity problems of black-holes.
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Old Feb 19th 2016, 07:54 PM   #8
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I agree MBW. There's no evidence which implies beyond a shadow of a doubt that there was a singularity at the "beginning" of the universe (whatever that means). See:
http://profmattstrassler.com/2014/03...a-singularity/
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Old Oct 31st 2016, 11:33 PM   #9
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I am aware that this is very dated thread, but to say hello I thought I would add my two cents to this discussion.

My understanding on the big bang as a theory is that space expanded, and that means that matter itself was also expanding, as matter is simply space being occupied by localized energy.

It's a circular rational, and for it to be valid all of the matter in the universe came from nothing, or a single point that violates all known laws of physics. It means the universe at one time was 1/0, then decided to go over 0 closer to 1 or 2 as is presumed today depending on which camp you're in on the matter.

I don't think anyone should be taking what is a relatively accurate theory on the geometry of space and presuming it describes the creation of the universe. I don't think anything would ever be that simple.
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Old Nov 8th 2016, 12:38 AM   #10
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Originally Posted by Pmb View Post
You're not taking into account that the universe was far too hot for neutrons to bind together, even when the strong force was acting to keep them together. I.e. simply put, the kinetic energy of the neutrons was far too great to let them bind together.
If space and time had no meaning at the singularity then why did temperature have meaning at the singularity. Isn't temperature based on average kinetic energy and therefore mass, velocity and time, from a thermodynamics perspective?
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