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Author Topic:   Cosmology Principle vs the actual center of the Universe
cavediver
Member (Idle past 3643 days)
Posts: 4129
From: UK
Joined: 06-16-2005


(1)
Message 5 of 38 (562263)
05-27-2010 11:53 AM
Reply to: Message 4 by hotjer
05-27-2010 8:52 AM


The strongest evidence of us, the earth , nor any point in the universe, not being the center of universe must be the observartion of cosmic microwave background radiation (CMB). To put it simple; the only explanation to how an uniform cooling of the univserse could occur is that the universe experiences a metric expansion.
Of course, your assumption is that the CMBR does in fact represent a "cooling" of the Universe. This assumption will be strongly challenged by any that seriously propose a centric universe. And actually it is the CMBR itself that provides the strongest evidence of our privilidged location and orientation in the Universe by way of the dreaded axis-of-evil

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cavediver
Member (Idle past 3643 days)
Posts: 4129
From: UK
Joined: 06-16-2005


(1)
Message 11 of 38 (564284)
06-09-2010 1:19 PM
Reply to: Message 7 by ramoss
06-08-2010 5:49 PM


Have they figured out what the results mean? Have they confirmed the data, or are the theories wrong?
This is the "axis-of-evil" that i jokingly refered to earlier. Over time, the statistical obviousness of this artifact has somewhat diminished and it is no longer the exciting/worrying anomaly that it was a few years back...

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cavediver
Member (Idle past 3643 days)
Posts: 4129
From: UK
Joined: 06-16-2005


(1)
Message 13 of 38 (564347)
06-10-2010 3:20 AM
Reply to: Message 12 by greentwiga
06-10-2010 1:44 AM


If we could see the edge of the universe
There is no "edge"
If it is not infinite, then there is a center of mass, but we just can't detect it.
No, there is no centre of mass, even if the Universe is finite. If finite, the spatial topology of the Universe is that of a 3-sphere. 3-spheres, like all other spheres, have neither edges nor centres.

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cavediver
Member (Idle past 3643 days)
Posts: 4129
From: UK
Joined: 06-16-2005


(1)
Message 16 of 38 (564426)
06-10-2010 12:26 PM
Reply to: Message 14 by Peepul
06-10-2010 6:44 AM


1-spheres and 2-spheres don't have centres? Can you explain?
Sure - a 1-sphere is a circle, a 1-dimensional line that loops back on itself. There is no unique point on the circle that can be considered "the" centre, but all points can equally be considered "a" centre. The 1-sphere is not to be confused with the 2-ball, which is a disc: a 2-dimensional area bounded by a 1-sphere (circle). The disc does possess a centre.
The 2-sphere is the 2-dimensional area that closes in on itself exemplified by the surface of the earth. Once again, there is no unique point on the 2-sphere that can be considered "the" centre, but all points can equally be considered "a" centre. The 2-sphere is not to be confused with the 3-ball, which is a solid 3-dimensional volume bounded by a 2-sphere. The earth is a reasonable 3-ball. The 3-ball does possess a centre.
The naive impression that n-spheres have centres occurs because n-spheres are most often visualised embedded in an n+1 dimensional space (circle drawn on piece of paper.) A point completely divorced from the n-sphere is viewed as the centre as it conincides with the centre of the corresponding n+1-ball.
Cool facts: the boundary of an n-ball is an n-1-sphere. An n-sphere has no boundary.

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cavediver
Member (Idle past 3643 days)
Posts: 4129
From: UK
Joined: 06-16-2005


(1)
Message 20 of 38 (571641)
08-01-2010 5:42 PM
Reply to: Message 18 by jar
07-31-2010 6:17 PM


Re: The no Big Bang model.
As a totally ignorant onlooker I wondered what you, cavediver and Son Goku might be able to tell us.
I think that Bikerman is being exceptionally generous. It's pure bollocks. Yes, we do experiment with all sorts of crazy ideas, in my case typically whilst otherwise engaged in the bathroom, but there is plenty of evidence from the paper that this guy is seriously confused on a number of issues.
Now, this could be an interesting article on what some random and completely un-physically motivated "nonsense" can produce, but to publish this garbage on arxiv as serious research puts this into crank territory, if only as it is an unashamed (and somewhat successful) attempt at making a name for oneself in pop-sci and the blog-sphere.

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cavediver
Member (Idle past 3643 days)
Posts: 4129
From: UK
Joined: 06-16-2005


(1)
Message 22 of 38 (571732)
08-02-2010 3:51 AM
Reply to: Message 21 by Bikerman
08-01-2010 6:19 PM


Re: The no Big Bang model.
Now don't hold back here...tell us what you REALLY think, and don't cloak it in these neutral non judgemental terms
Strangely, after several years attempting to coach ICANT and Buzsaw in the rudiments of cosmology, I found that my once bountiful patience had been eroded down to a blackened core of harsh intolerance towards bullshit. Carry on in your current form with them, and you are only seeing in me what lies in your own future...

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cavediver
Member (Idle past 3643 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 28 of 38 (581115)
09-13-2010 7:08 PM
Reply to: Message 27 by Modulous
09-13-2010 11:04 AM


Because the 'location' where it occurred is 'everywhere'.
Exactly - and the same is true with the surface of last scattering.

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cavediver
Member (Idle past 3643 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 33 of 38 (581241)
09-14-2010 6:21 PM
Reply to: Message 32 by Dogmafood
09-14-2010 5:33 PM


It seems to me that you are saying that all of the galaxies in the universe are not moving apart but that there is an increasing amount of space between them.
That is exactly what he is saying.
That doesnt make sense to me.
Tough
Look at this video. When I imagine the BB I see something like this only shaped as a sphere.
Yep. That's why everyone has a completely wrong idea about the Big Bang: from watching videos like this one. The Big Bang is simply the beginning of the expansion of the Universe. It is in no way an explosion - it wasn't Big and it didn't go Bang.

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cavediver
Member (Idle past 3643 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 36 of 38 (581249)
09-14-2010 6:47 PM
Reply to: Message 34 by Dogmafood
09-14-2010 6:36 PM


Well now why would they go and call it the Big Bang then?
As nwr says above...
Are there any books that you would recommend?
"The first three minutes" by Steven Weinberg, if it's still available.

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