Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: tommya300 on 13/07/2010 02:15:50

Title: Was the Big Bang a rapid expansion? The sub question has more detail.
Post by: tommya300 on 13/07/2010 02:15:50
"The name is only used to describe that the origin of the universe was a rapid expansion of space that could be thought of as being similar (but not identical) to an explosion."
(Soul Surfer, I am not contesting the statement, I needed to use your statement in a different thread not to sidetrack the other thread. It just inspired another question.

Reference to the Big Bang. This is the question!

Was the Big Bang an expansion of space or was it an expansion of matter from a singularity into the already vacuum of space?

Title: Was the Big Bang a rapid expansion? The sub question has more detail.
Post by: PhysBang on 13/07/2010 03:08:33
There was no "big bang" event. The big bang theory states that the space of the universe expanded from an earlier state where the universe was much more dense and hot. How the universe got into that earlier state is unknown.
Title: Was the Big Bang a rapid expansion? The sub question has more detail.
Post by: Democritus on 13/07/2010 15:04:56
Regarding the 'Big Bang', it wasn't big and it didn't go 'bang!' It took a silent age to achieve the size of a grapefruit...The extraordinary Fred Hoyle coined the term 'Big Bang' as a description of derision. He was of the 'Steady State' theory of origins then. Nonetheless, Fred made great strides forward towards our understanding of stellar evolution and stellar nuclear synthesis. And, in his day, was again criticised for his theories of panspermia: the notion that life may have been seeded on Earth from interplanetary or interstellar dustings. This seems to be an increasingly less ludicrous idea of late. While Fred described how stars work,to the Nobel committee's shame, Fred never got the prize.   
Title: Was the Big Bang a rapid expansion? The sub question has more detail.
Post by: PhysBang on 13/07/2010 16:42:28
Yeah, Hoyle did some really good work. Even his early work on the steady state theory is quite good. Later work, not so much.
Title: Was the Big Bang a rapid expansion? The sub question has more detail.
Post by: yor_on on 11/06/2011 23:27:24
Hoyle was a brilliant guy. As I've read about him he was a guy always caring about his students and without the need to 'prove himself' in discussions. He was the one solving the mystery with how atoms heavier than hydrogen and helium could be created. And, even though having his own theory about how the universe should be destroyed by solving it, as all atoms now could be described from a Big Bang he was cool about it.

He should really have had a Nobel prize, but he seemed to have collided with with other peoples opinions a little too much for them acting fairly. And when the Nobel committee had been 'exchanged' by new faces, enough to present him with it, he was already dead and so impossible to give it too (this as I understands it). You have to be alive to receive it apparently, a rather silly idea as any work worthy of a Nobel Prize will last much longer than any committee deciding about it.

He lost heart working at Cambridge, resigning 1972, after complaining that he was expected to spend more time spying on his colleagues and doing the 'right political things' than researching. After that he moved around a lot it seems between universities. But he was the guy creating the bridge that was missing between different elements, a scientist of the best kind.

He also wrote one of the best SF:s I've read. It must be, as I remember it still :)
Worth reading today too if you like a cool book. "The black cloud"

(Hmm, mixed the date there 1927 instead of 1972, I'll blame my keyboard for that one.
It's not cooperating.)
Title: Was the Big Bang a rapid expansion? The sub question has more detail.
Post by: Soul Surfer on 13/06/2011 10:10:33
Yes I am a great respecter of the work of Fred Hoyle.  The important philosophical principle behind his attempt to build a steady state theory is called the "perfect cosmological principle"  it states that, looked at on the largest scales of space and time, the universe(/multiverse) must look similar for all space and time.  The steady state theory was posed as a simple (and disprovable) cosmology that made this constant state what we see in our universe.  We have now proved beyond reasonable doubt that our universe started at a specific time and will run a course to an eventual heat death.  Disproving the steady state theory advanced science greatly at a time when ideas were getting bogged down

The concept of universes with a limited life implies the somewhat unsatisfactory situation that all life is limited in duration and there is no such thing as eternity on our remit.  (a lot of religions find this concept very hard to stomach) 

In Fred Hoyle's time  (and I was there) the concept of multiple universes or a multiverse was virtually unknown and given current knowledge I am sure that he would propose a different theory with the same principle and the same potential.

I would suggest that the hypothesis he would chose is that every black hole in our universe is a new universe which could be as "large" as ours and has been seeded with material from our universe.  Furthermore the physical laws that apply in our universe have "evolved" to maximise this possibility which in turn lead to the possibility of intelligent life.  That is it is highly probable that many other universes are living universes.  This too is a disprovable and simple hypothesis and exploring this simple concept both with theory and practical experiments could advance fundamental science greatly.  This is a concept that is slowly growing in favour in some official cosmological circles notably Lee Smolin.

Most multiverse theories suggest that the probability of living universes is very low.  This approah would completely turn the concept of the sterile multiverse on its head.