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Author Topic:   Universe Race
Son Goku
Inactive Member


Message 166 of 410 (457763)
02-25-2008 11:48 AM
Reply to: Message 165 by ICANT
02-24-2008 10:29 PM


Re: Re-Is This Correct
Some of what you said is right. I will follow your sentences with what the big bang theory actually says.
The Big Bang did not happen in the universe.
The Big Bang was an expansion that happened to the universe.
The Big Bang created the universe.
There is an expansion of the universe which has been occuring for at least 13.7 billion years. It did not create the universe because, as far back as we can model, the universe was already there.
Universe emerged from a singularity at T=O.
The expansion has been occuring for 13.7 billion years. What occured before that is unknown because GR produces a singularity and hence breaks down.
Describes what happened from 0.0001 of a second after this moment of creation.
The Big Bang says nothing about what preceded it, so its predictions can not be dated relative to some "moment of creation".
Temperature was 1,000 billion degrees Kelvin.
Far higher than that. Up to quintillions of degrees Kelvin.
The density was that of nuclear matter, 1014 grams per cubic centimetre.
10,000 times less dense than that.
I am assuming that by saying "density was" or "temperture was", that you are referring to times we can describe, like the elctroweak epoch.
Edited by Son Goku, : Clarification of last two sentences.

This message is a reply to:
 Message 165 by ICANT, posted 02-24-2008 10:29 PM ICANT has replied

Replies to this message:
 Message 168 by ICANT, posted 02-25-2008 3:11 PM Son Goku has replied

Son Goku
Inactive Member


Message 169 of 410 (457791)
02-25-2008 3:28 PM
Reply to: Message 168 by ICANT
02-25-2008 3:11 PM


The singularity is not real.
If we are talking about a singularity, what activated the singularity to create time, for the universe, space, and matter to exist in?
The singularity isn't real, it is a mathematical artefact due to the break down of GR. It wasn't physically activated because it is not real. This has been stated several times.
Is this agreement that a singularity was at T=O?
Before this point, GR produces a singularity. However it isn't real. It's existence is not a prediction of the Big Bang theory.
Is this agreement that The Big Bang trys to describe what happened from 0.0001 (or there abouts) until today.
It describes from a period when the electroweak force existed 13.7 billion years ago to today.
What would be the density at singularity?
What could cause such density?
The singularity isn't real, it comes about as a breakdown in the mathematics.
I don't think we have any way of knowing other than by making an assumption.
We have no way of knowing, because the singularity is not real.
Please, for the sake of my sanity, do not ask questions in the next post which assume the singularity is a real physical object.

This message is a reply to:
 Message 168 by ICANT, posted 02-25-2008 3:11 PM ICANT has replied

Replies to this message:
 Message 170 by cavediver, posted 02-25-2008 3:37 PM Son Goku has not replied
 Message 171 by ICANT, posted 02-25-2008 3:49 PM Son Goku has replied
 Message 173 by randman, posted 02-25-2008 4:31 PM Son Goku has not replied

Son Goku
Inactive Member


Message 172 of 410 (457803)
02-25-2008 4:10 PM
Reply to: Message 171 by ICANT
02-25-2008 3:49 PM


Re: The singularity is not real.
GR says there was a singularity at T=O. You say that singularity is not real. That leaves an absence of anything at T=O.
No, it leads to an absence of a statement or any kind of prediction about T=0. The Big Bang theory doesn't says anything about what went on then. It certainly doesn't say there was an absence of anything.
The singularity is the mathematical equivalent of "I don't know what is going on here".
"I don't know what is going on here" is in no way equivalent to "I know what was going on here, there was nothing".

This message is a reply to:
 Message 171 by ICANT, posted 02-25-2008 3:49 PM ICANT has replied

Replies to this message:
 Message 176 by ICANT, posted 02-25-2008 6:09 PM Son Goku has replied

Son Goku
Inactive Member


Message 181 of 410 (457902)
02-26-2008 8:51 AM
Reply to: Message 176 by ICANT
02-25-2008 6:09 PM


Re: The singularity is not real.
OK we have established that there definitely was something at T=O.
Did this something exist in time and space?
If not where did it exist?
I can't really add anything beyond the answers of Chiroptera and Rahvin. As Chiroptera said there could be anything preceding the point where we can't model. The universe may have existed for billions of years before that and time itself might break down as a concept. I don't know anything about the period before GR breaks down. So I don't know:
(a)The answers to your questions.
(b)If your questions make sense, as the future theory might render such questions inapplicable.
We can't establish anything about T=0. The Big Bang is not a theory of origins.

This message is a reply to:
 Message 176 by ICANT, posted 02-25-2008 6:09 PM ICANT has replied

Replies to this message:
 Message 182 by ICANT, posted 02-26-2008 4:17 PM Son Goku has not replied

Son Goku
Inactive Member


Message 195 of 410 (458083)
02-27-2008 6:32 AM
Reply to: Message 194 by ICANT
02-26-2008 11:12 PM


For the Aleph-Zeroth time.....
So to trust the Big Bang Theory I have to make some assumptions concerning how it happened.
Hawking does not mean initial conditions in the sense of "how the universe began". He is making the fairly simple statement that dynamical laws evolve an initial state. However that initial state doesn't have to be the beginning of everything.
However at this point your questions have become overtly ridiculous. You have been repeatedly told that science says nothing about what was going on at T=0 and yet in your previous post you ask:
So to trust the Big Bang Theory I have to make some assumptions concerning how it happened.
That sounds like I got to believe it happened the way Science says it was just because Science says it was.
Even though science says nothing about the "way it was", you somehow feel you must accept the "way science says it was". You (somehow) reject an explanation that nobody has offered.
In my opinion the statement "Science doesn't know, because we have no evidence" is simply too scientific for you. Instead, you want there to be some materialist/atheist origin story, which you can then ridicule. I can tell you now; there is no point, because such a thing does not exist. There is only the experimentally verified Big Bang theory of the evolution of the universe from 13.7 billion years ago to today and that theory is not a theory of origins.
Either you come to an understanding of this or this thread will simply be a collection of synonyms of "We don't know what went on at T=0".

This message is a reply to:
 Message 194 by ICANT, posted 02-26-2008 11:12 PM ICANT has replied

Replies to this message:
 Message 197 by ICANT, posted 02-27-2008 9:01 AM Son Goku has replied
 Message 230 by Chiroptera, posted 02-28-2008 8:12 PM Son Goku has replied

Son Goku
Inactive Member


Message 208 of 410 (458192)
02-27-2008 4:35 PM
Reply to: Message 197 by ICANT
02-27-2008 9:01 AM


Re: For the Aleph-Zeroth time.....
But there is such an origin story. It just happened. Proof, we are here.
That is the origin story of Frank, the fictional sterotypical atheist. It is not the explanation offered by the big bang theory. So please cut the nonsense.
Everything I find on the faster than the speed of light says it can't happen.
Cavediver was being loose with his words. Something which he already explained. Space didn't really expand faster than light, that's just a nice way of intuiting it. Really the distances between galaxies increase in way that makes it look as if they are moving faster than light. Think of it as the universe manufacturing distance.
If space is expanding between every quarks & leptons at light speed, how did anything get together to form anything?
That unfortunately is too difficult to explain and takes a semester long course in graduate cosmology. Not because it is too "mind-bending" or something, it's simply very involved. Sort of like asking to see Windows XP's source code. Basically it is related to how densities scale with increasing distance. The expansion doesn't really overcome the formation of structures like galaxies.

This message is a reply to:
 Message 197 by ICANT, posted 02-27-2008 9:01 AM ICANT has not replied

Son Goku
Inactive Member


Message 209 of 410 (458196)
02-27-2008 4:46 PM
Reply to: Message 205 by ICANT
02-27-2008 2:37 PM


Re: I Don't Know -- sometimes a good answer.
The first thing that had to be added was inflation.
Then there is the biggest fudge factor of all called dark matter.
Which is invisible, can not be detected, makes up most of the universe, yet is accepted as a fact.
Without either of these the Big Bang Theory fails.
The Big Bang does not require inflation (assuming you are talking about what is usually called inflation). Inflation is a possible extension of the Big Bang Theory.
As for Dark Matter it has been detected. See here:
http://math.ucr.edu/home/baez/week238.html
This is quite an old article, but explains things well. By now the bullet cluster is looking more and more like it is dark matter.

This message is a reply to:
 Message 205 by ICANT, posted 02-27-2008 2:37 PM ICANT has replied

Replies to this message:
 Message 212 by ICANT, posted 02-27-2008 5:26 PM Son Goku has replied

Son Goku
Inactive Member


Message 219 of 410 (458289)
02-28-2008 6:37 AM
Reply to: Message 212 by ICANT
02-27-2008 5:26 PM


Re: I Don't Know -- sometimes a good answer.
If the admins consider this off-topic I'll drop it, since it is more relevant to cosmology in general rather than the big bang.
Seems real and being real are two different things.
I can not find anything present to change the above statement.
This is very vague, could you be more clear as to what you are saying. Also you obviously didn't pay attention to the rest of my post. I knew you would pick on this paragraph:
John Baez writes:
Nonetheless, dark matter is seeming more and more real. It thus becomes ever more interesting to find out what dark matter actually is. The lightest neutralino? Axions? Theoretical physicists are good at inventing plausible candidates, but finding them is another thing.
Which is why I told you:
This is quite an old article, but explains things well. By now the bullet cluster is looking more and more like it is dark matter.
However this doesn't really relate to the Big Bang, so I'm not sure what you're getting at now. Why have you suddenly decided to switch to criticisms of dark matter?

This message is a reply to:
 Message 212 by ICANT, posted 02-27-2008 5:26 PM ICANT has replied

Replies to this message:
 Message 221 by ICANT, posted 02-28-2008 8:45 AM Son Goku has not replied

Son Goku
Inactive Member


Message 278 of 410 (459270)
03-05-2008 10:26 AM
Reply to: Message 230 by Chiroptera
02-28-2008 8:12 PM


Re: For the Aleph-Zeroth time.....
I just taught my math classes about Aleph-naught. Their test is Monday.
It must be cool to be a teacher. Did they buy/trust it? I know a lot of people don't like notions from Cantorian set theory. I remember telling my younger brother about Cardinality using bus seats. Basically if you get on bus with seats labelled by the natural numbers all the real numbers can't sit down on them.
To the thread in general:
New cosmological data has just been obtained from the WMAP's fifth year. You will probably hear about it in the next coming days.

This message is a reply to:
 Message 230 by Chiroptera, posted 02-28-2008 8:12 PM Chiroptera has replied

Replies to this message:
 Message 279 by Chiroptera, posted 03-05-2008 8:44 PM Son Goku has not replied

Son Goku
Inactive Member


Message 284 of 410 (459423)
03-07-2008 7:38 AM
Reply to: Message 280 by ICANT
03-06-2008 7:42 PM


Re: Re-Inflation
Cosmology is a very fast moving discpline so quoting articles from June 2006 concerning Dark Matter are unimportant considering our first major piece of empirical evidence for Dark Matter was obtained in August 2006. Until the observation of the bullet cluster, physicists who objected to dark matter had a fairly decent case. Now however they have a much weaker case.
The second link to open-site.org is utter nonsense. The people who wrote that article have a very odd coneption of what dark matter is supposed to resolve. In fact this is an issue I encounter over and over again on this forum and on the internet in general, people who seemingly can't stand dark matter for some reason and are convinced it's presence as a hypothesis is due to dogma in the academic community. Pointing out the bullet cluster observations causes no response from these people, as if it were irrelevant. I would appreciate if some posters would tell me how dark matter is described in pop-science books, so that I can understand this.
ICANT, the universe is supposed to be homogeneous on the largest scales, not on galatic scales. The clumpiness of the galactic scale comes from perturbations. (Described by a cut down version of General Relativity called linearized GR.) This has nothing to do with dark matter.
By the way the recent WMAP 5-year study has revealed some interesting information about our universe for those interested. This is very recent stuff, the results have only been released on monday.
1. Everything is consistent with the GR+Dark Matter+Dark Energy hypothesis, even more so than people expected.
2. Recombination (the point at which the universe started looking like black void instead of a totally opaque fluid) occured roughly 375,900 (+- 3,100) years after the big bang period.
3. You can find energy density comparisons at different times here:
http://space.newscientist.com/...s/dn13414/dn13414-2_340.jpg

This message is a reply to:
 Message 280 by ICANT, posted 03-06-2008 7:42 PM ICANT has replied

Replies to this message:
 Message 289 by ICANT, posted 03-07-2008 2:10 PM Son Goku has not replied

Son Goku
Inactive Member


Message 309 of 410 (459513)
03-08-2008 9:15 AM
Reply to: Message 305 by Percy
03-08-2008 7:39 AM


Structure scale
Good question and believe it or not these scale related question tie in with what is known as renormalization, but that's for another thread.
Basically imagine the universe as whipped cream (a fairly homogeneous substance) in a bowl. Take a bowl about 15 centimetres across. Then the Bootes void is only about four millimetres across. A four millimetre bubble of air in a 15 centimetre bowl hardly spoils homogeneity and won't really affect the motion of the cream.
Basically an inhomogeneity is too big if it actually affects the overall motion.

This message is a reply to:
 Message 305 by Percy, posted 03-08-2008 7:39 AM Percy has not replied

Replies to this message:
 Message 312 by ICANT, posted 03-08-2008 9:35 AM Son Goku has not replied

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