Why is the existence of The Big Bang agreed upon?

  • #26
Simon Bridge
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Yes OK - from Post #17 - "possible to model the whole universe as a white hole".

Not sure how this is different from putting the whole universe inside a(n eternal) black hole though... arn't they supposed to be ends for the same thing?

Also - this model cannot start the universe at the white-hole end (which seems to be what the "push" idea ventured earlier seems to suggest) ... surely the universe, in this situation, has to be approaching it?

ref:
http://members.cox.net/jhaldenwang/black_hole.htm
... how out of date is this?
 
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  • #28
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Problem is, white holes don't even make sense. Gravity has no repulsive counterpart.
Dave,

Would the LGQ bounce theory on repulsive gravitational "force" at quantum levels be able to explain this? I remember looking at an Ashtekar paper which proposed a slight modification of the EFE at quantum levels that was a mathematical fit - observational evidence for this is obviously a little bit more hard to come by!

Essentially if you look at it that way then a black hole is a black hole from our FoR but from FoR of anything within the blackhole can consist of a classically contracting spacetime required for a LQG style bounce. So while white holes have no observational evidence, if they were hidden behind EH of BH's that would be very interesting!

I am in no way promoting any theory just enjoying this discussion and value your/other members opinions on this.

Just food for thought.
 
  • #29
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I am in no way promoting any theory just enjoying this discussion and value your/other members opinions on this.
Here, here.

Dave, I'd just like to echo that sentiment. One of the best discussions in a long, long time. I really like what you are saying and the way you are presenting it.

Regards,

Noel.
 
  • #30


Since were not just expanding, but accelerating! Doesn't this point to evidence of some type of "anti-gravity" or repulsion? In the early universe Gravity ruled all because all these new massive objects being extremely close to each other. But what now?
 
  • #31
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Maybe the question shouldn't be why is the universe expanding but why does it appear to be.
 
  • #32
phinds
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Since were not just expanding, but accelerating! Doesn't this point to evidence of some type of "anti-gravity" or repulsion?
Well, yes it sure does ... we call this "dark energy". Look it up.
 
  • #33
phinds
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Maybe the question shouldn't be why is the universe expanding but why does it appear to be.
Why do you think it is not?
 
  • #34


Would there be any consequences on the timeline, or should I say would there be any consequences on the unification of forces if the Higgs aint found? What would change, specifically what would change about the way of looking at the Electroweak and Electronuclear forces, if there would be any change at all?

Also, not to go off-topic, Id like to continue the current discussion, but do the electroweak/electronuclear bosons still travel at c? Do they have a shorter range than the EM force?
 
  • #35


RE reply #9. Sudden violent expansion is exactly what an explosion is. There can have been no greater, nor more violent, rate of expansion than that provided by "inflation". This would have provided the ballistic impetus, (if "inflation" actually happened). Gravitational restraint would bring about the faster with distance view. Proof of this will be evidenced if we should see an increase in the rate at which galaxies move apart. Observers should be warned that this will give the impression of acceleration!
"As a rule, the more bizarre a thing is, the less mysterious it proves to be". (Sir Arthur Conan Doyle)
 
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  • #36
phinds
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RE reply #9. Sudden violent expansion is exactly what an explosion is. There can have been no greater, nor more violent, rate of expansion than that provided by "inflation". This would have provided the ballistic impetus, (if "inflation" actually happened). Gravitational restraint would bring about the faster with distance view. Proof of this will be evidenced if we should see an increase in the rate at which galaxies move apart. Observers should be warned that this will give the impression of acceleration!
"As a rule, the more bizarre a thing is, the less mysterious it proves to be". (Sir Arthur Conan Doyle)
Yes, but an explosion happens at a PLACE. The expansion happened everywhere at once.

I Can't really comment on the rest of your post but to say that it doesn't make sense to me except for the Doyle quote.
 
  • #37


All visual evidence, and the inflation theory, and the inflating balloon theory states that the big bang did take place at a single point in time and space, away from which all matter is moving. All the "rewinding", over four decades, in order to establish our age, point to this being the case, and being believed to be the case. There is no evidence that states otherwise.
 
  • #38
DaveC426913
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... the inflating balloon theory ...
Analogy. It's just an analogy to help people having trouble understanding. It has no predictive ability.

states that the big bang did take place at a single point in time and space,
A single point in time, yes. Single point in space, no.

It took place of space, not in space. i.e. everywhere in space.
 
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  • #39
phinds
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All visual evidence, and the inflation theory, and the inflating balloon theory states that the big bang did take place at a single point in time and space, away from which all matter is moving. All the "rewinding", over four decades, in order to establish our age, point to this being the case, and being believed to be the case. There is no evidence that states otherwise.
Quite the contrary. ALL evidence states otherwise. You really should read up on this stuff before you make such incorrect pronouncements.
 
  • #40
Simon Bridge
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Peter has got the wrong end of the stick about how we get the age of the Universe from Hubble expansion.

The traditional big bang theory says that space and time expanded suddenly from a singularity ... that is to say that the universe had a state in which all time and space were the same place. This would be represented by a point in 4D - but that point does not have a specific location within space-time - it is space time.

The Hubble expansion does not procede from a particular (x,y,z) position in space which could be considered the center of some explosion. No matter where you are, you will discover yourself at the center of the expansion - ergo: it is everywhere at once.

It is a very common misconception. But fair enough - it's a tricky concept.
 
  • #41
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I am not as learned as most (all of you) but I think the misconception at the beginning of this thread with black holes and white holes is that the first poster viewed black holes as funnels to somewhere like a tornado. A black hole does not take matter and transfer it somewhere else it take the matter and keeps it. The "funnel" concept is what is used to depict black holes on TV and movies and confuses people, they tend to think of black holes like powerfully attractive worm holes that transport matter from one point to another. Another universe where the "backend" of a black holes spits out matter as a white hole. I apologize if I am wrong about his misconception but this is how many of the "lay people" I know view black holes.
 
  • #42


So what is the evidence that states otherwise, bearing in mind the the einstein on line website, promoted by Marcus, states that "rewinding" the expansion would bring us to a single point.
 
  • #43


Re #36. Are you saying that you cannot understand the effect that gravity would have upon a large mass of expanding matter, and how it would produce the "faster with distance" view?
 
  • #44
DaveC426913
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So what is the evidence that states otherwise, bearing in mind the the einstein on line website, promoted by Marcus, states that "rewinding" the expansion would bring us to a single point.
Re #36. Are you saying that you cannot understand the effect that gravity would have upon a large mass of expanding matter, and how it would produce the "faster with distance" view?
Please use the quote feature. It is very difficult to figure out exactly what your responses are referring to.
 
  • #45


How do I do that? Is it as simple as just ticking the box?
 
  • #46
russ_watters
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Sorry Dave....thread locked.
 

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