I have to say here, we have pictures of the universe before any galaxies existed at all. The galaxies are of course made up of stars and gas and dust.
We know the first starts starting forming around 200 million years after the bang.
"There is no reason to think it will shrink into an infinitly dense point."
actually there is
"When you bring all that stuff very close together how will it behave?"
a singularity, although different then a black hole singularity.
"
I am beginning to think that all we are arguing over is the meaning of words.
The word singulatity in particulat
Take your ballon example.
It is true that when you let out the air it shrinks, but it doesn't shrink to a point. it shrinks to a limp peace of plastic"
This is not a good analogy.
It was originally
Call_of_the_Wild's analogy.
I was just trying to indicate that you have to be careful when you apply simple mathematical formulas to the real world as it may not be an adequate description in all cases.
If you go back as far as you can in planck time, you get all four fundemental forces combined.
Right, but that does NOT make it a singularity.
a planck distance is NOT zero.
...
lunakilo, are you aware of the Cosmic Background Radation and what it actually is and tells us?
Wilkinson Microwave Anisotropy Probe (WMAP)
I did take basic cosmology once upon a time
The cosmic background radiation is assumed to be the 'light' that was let loose when the universe 'became transparent'.
That is when the universe cooled to about 2.7 K and protons and electrons could form neutral atoms. In contrast to the proton/electron plasma, the neutral atoms did no longer absorbed the photons, leaving them to travel freely.
The fact that they were let loose with an energy of 2.7K means they have a spectrum of a black body of 2.7 K which peeks in the microwave range.
What this tells us is that the universe was once so hot and dense that atoms could not exist. It then expanded and cooled allowing atoms to form.
It expanded then about (13.7 billion years ago) and it is still expanding.
My objection to what
Call_of_the_Wild writes is that he extrapolates back in time far beyond this point even though we don't really know how things behave under such extreme conditions.
High energy particle physics is trying to push back the line, but we hit a point beyond which we
just don't know what happened.
Assuming that everything would collapes into a point is assuming that only attractive forces are at work.
As you said "If you go back as far as you can in planck time, you get all four fundemental forces combined.", but we don't (to my knowledge) yet have a proper theory which combines these.
So all this talk about the singulatity that
must have existed makes no sense to me.