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Calibre
2003-Dec-20, 09:37 AM
I'm just busy doing some writing and have run up against the question.. "Why did the big bang produce an expanding (white?) explosion instead of a contracting blackness we think of as a blackhole?"

My first thought is that it took a while for dense matter to evolve and that a huge amount of dense (evolved) matter is capable of causing reality to collapse. While the early bang simply produced energy.

Any comments? I'm trying to quickly prologue the early universe formation skimming through to evolution of G class stars.

Littlemews
2003-Dec-20, 07:05 PM
I think u should read about Olber's Paradox...

Blackness :

Did the big bang really happen?
*If the Universe is infinite and filled with star, then why is the night sky black?
- in every direction we look, we should eventually see a star
- the sky should be ablaze with light

*solved by expansion
- starlight gets redshifted out of the visible range
- since light travel at a finite speed, if the Universe had a beginning, then there would be a limit on the number of visible stars

Early big Bang:

(I lost part of my note, whlie copying the big bang period table ><)

Planck Era -----&#62; GUT Era ------&#62; Electroweak Era ------&#62; Particle Era -------&#62; Era of Nucleosynthesis -------&#62; Era of Nuclei --------&#62; Era of Atom -------&#62; Era of Galaxies

Universe begin as tiny, hot, dense point of matter and radiation in an instant in time.

Planck Era - we dont know much about this Era

GUT Era - 4 forces act as one : Gravity (all particles), electronmagnetism (Change Particle), Weak force (Fission and fusion of nuclei), Strong force (bind atomic nuclei)
*At 10 to the -43 sec, gravity split off
*At 10 to the -38 sec, strong force split off
*Energy released caused sudden and dramatic inflation of size of the universe
*From size of nucleus to size of solar system

Electroweak Era
*EM and weak force unified till 0.000000001 sec

Particle Era
*Particel made
*1000000000 antiprotons
(Universe mad of matter not antimatter)

Era of NS
*Formation of Nuclei
*75% Hydrogen
*25% Helium

Era of Nuclei
*H & He nuclei and electrons
*Temperature 3000 K

Final Era of Atoms and Era of Galaxies
*Form about 1 billion yrs after the big bang

(Correct me if there is any mistake here)

Fraser
2003-Dec-20, 07:09 PM
It&#39;s a good question, though. You&#39;d think a point of matter the mass of the entire Universe would act like a super black hole. Why would it explode?

Calibre
2003-Dec-20, 10:21 PM
Thanks Littlemews, useful

One thought on Blackness:

Most stars of O, A and F type will have already burnt out, unless they are "new borns", only having short life spans up to a few hundred million years. We seam to know about many near by white dwarfs, and they only last a short while before fading to black, must be many within say 30 light years that we can&#39;t see. K and M class stars should not have burnt out yet, but must be rather close to be visible, some will last like 25 Billion years.

I&#39;ve always wondered about the dark matter debate, when it seams obvious that a huge proportion of the universes matter would be tied up by burnt out white dwarfs, too dull to see from far away and dull nuetron stars within a few million years.

Matthew
2003-Dec-21, 12:58 AM
We don&#39;t really know all that much about the first 3 seconds of the universe.


Final Era of Atoms and Era of Galaxies
*Form about 1 billion yrs after the big bang

1 billion years? I never thought it took that long.