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Ziggurat
2002-Feb-08, 07:27 PM
Hey Everyone,

I've been reading the 'board for a few days now, and I must say that these topics are all pretty fascinating to a non-astronomer like myself.

I noticed that a good chunk of time in the Against the Mainstream section is devoted to attempting to destroy or validate the Big Bang Theory once and for all.

My question is, I've heard said that the Big Bang is the best theory out there to describe the origin of the universe. Are there any other "credible" (at least, somewhat) theories of how the universe was created?

Sorry if I posted this in the wrong area, or this is a re-tread of something someone already talked about.

Ziggurat

Donnie B.
2002-Feb-08, 09:21 PM
The modified Big Bang (with inflation) model is very widely accepted among professional astrophysicists and cosmologists.

There are a few "flavors" of Big Bang, such as the one-shot and recycling versions. There isn't quite enough data to decide between these, at least not yet.

Other possible cosmologies are "on the outs" at the moment, because they don't fit as well with the observed universe. Any serious cosmology has to either predict or be consistent with the correlation of red**** with distance (i.e. expansion), cosmic background radiation, elemental abundance and matter distribution, and other large-scale properties of the universe.

Historically, the main competition to Big Bang cosmologies was another family of theories called "Steady-State" cosmologies. These propose that the universe looks more or less the same at any time; as the universe expands, new matter is created to replenish what has expanded away. One big difficulty with these theories is explaining how and why the new matter appears, and in just the right amount to keep things in balance.

More "fringe" theories reject the interpretation of some or all of the empirical evidence, postulating (for example) that red**** arises from some mechanism other than motion of the source, or that the laws of Physics are not completely consistent at all times and places in the cosmos.

And, of course, there are those who insist that their preferred sacred writings have it exactly right, and anything science comes up with has to be disregarded or made to fit with the revealed truth.

AstroMike
2002-Feb-08, 10:08 PM
Hoyle's "Steady-State" theory failed because of the discovery of cosmic background radiation that supports the "Big Bang".

Michael
2002-Feb-09, 10:54 AM
Hoyle's "Steady-State" theory failed because of the discovery of cosmic background radiation that supports the "Big Bang".

I really don't see how the background radiation suppurts the Big Bang. Looking at the following web site, it looks like the Big Bangers made huge fools of themselves, with their preditions of the background tempertures (such as Gamow's 50 K).

http://www.dfi.uem.br/~macedane/history_of_2.7k.html

Michael
2002-Feb-09, 10:57 AM
My question is, I've heard said that the Big Bang is the best theory out there to describe the origin of the universe. Are there any other "credible" (at least, somewhat) theories of how the universe was created?

Personally, I don't think the universe was created. It seems, to me, that nothingness is a bad building material.

2002-Feb-09, 01:55 PM
<a name="20020209.7:21"> page 20020209.7:21 aka Users?
On 2002-02-09 05:54, Michael wrote: To? 1 EB 10 PAX
Username: Michael
Joined: Jan 29, 2002 (0.35 Messages per day)
(such as Gamow's 50 K).posts: 4 (0.06% of total)
7:22 A.M. as A Gamow fan
http://www.dfi.uem.br/~macedane/history_of_2.7k.html
7:23 A.M. NO i'll not claim Groupiee status [x} Not G
7:24 A.M. and i DO not know about the 50 K number?
whats the reference for that 1?

2002-Feb-09, 02:05 PM
<a name="20020209.7:27"> page 20020209.7:27 aka USER2
On 2002-02-08 14:27, Ziggurat wrote: To: 1 EB 10 PAX
Hey Everyone,<pre>1:Username: Ziggurat
2:Joined: Feb 08, 2002 (0.73 Messages per day)
3:posts: 1 (0.01% of total)
4: FOUR my point it does NOT matter 2 me
5: if the universe Expands or if Time
6: has contractions, weather it was Created
7: Cratered, or made in Japan..
8: OR even if it actually exists as far as
9: that goes.. As I `poise it possible
8: Like a TV picture it may be somethin
Ziggurat7: THAT's just recieved on a 3D
6: reciever and could LIKE TV simply be
5: turned off? I donno, dont much care. I do Question these 2 posts though. Delete as required

AstroMike
2002-Feb-09, 04:26 PM
Michael: Looking at the following web site, it looks like the Big Bangers made huge fools of themselves, with their preditions of the background tempertures (such as Gamow's 50 K).

Are you a cosmologist Michael? Perhaps you should start reading some astrophysics books.

John Kierein
2002-Feb-09, 04:35 PM
The question is meaningless. The universe was not created, it's always been there. It's an "Endless, boundless, stable universe" according to Reber. See:
http://www.geocities.com/CapeCanaveral/9335/G_Reber.html
As far as the background radiation is concerned, the big bang is a really bad predictor. Look here: http://www.dfi.uem.br/~macedane/history_of_2.7k.html

AstroMike
2002-Feb-09, 04:50 PM
Interesting article. Unfortunately, it doesn't really explain how the Big Bang is a really bad "predictor". It try to holds evidence against it and the Steady-State. These people perhaps should read Hawking's book "A Brief History of Time".

AstroMike
2002-Feb-09, 05:02 PM
As for Reber's theory, I do agree that time has no beginning or ending, but don't agree that the Universe is "endless" and "stable".

Pi Man
2002-May-12, 03:14 AM
I'm not sure, but I think I heard that Hoyle(or one of his followers) came up with a reason for the background radiation from his Steady State theory.

David Hall
2002-May-12, 09:28 AM
I've always been interested in the plasma cosmology theory. It's mostly overlooked and it's unique in that is wasn't developed by cosmologists, but by plasma physicists.

Simply put, the electromagnetic force is many times stronger than gravity. It shows itself particularly in plasmas, which are ionized gasses. Since most of the universe is filled with ionized hydrogen, the theory comes to the conclusion that many of the things we see can be explained by plasma forces.

Now, just like the steady-state theories, plasma cosmology has a lot of holes in it, so I still accept the BB model as the most accurate. But I think that cosmologists would do well to at least look at these ideas and maybe incorporate some of them into their own theories.

http://public.lanl.gov/alp/plasma/TheUniverse.html

John Kierein
2002-May-12, 03:32 PM
I like that plasma universe website. I've managed to meet several of the folks involved. I had the privilege of having lunch with Nobel Laureate Hannes Alfven in San Diego before he passed away, along with Tony Peratt of Los Alamos. Also worked with Tim Eastman when he was at NASA on leave from the NSF. I also have had Reber at my house a few times, and have met with Arp at Cal Tech and at a conference at U. Conn. Wonderful group of folks willing to consider that the big bang could be wrong. I like the quote from Hubble!

John Kierein
2002-May-13, 02:54 PM
http://www.washingtonpost.com/wp-dyn/articles/A8245-2002May12.html

Spaceman Spiff
2002-May-13, 09:27 PM
But, note, there is NOTHING in Turok's and
Steinhardt's model that in anyway invalidates
the hot big bang model in its most general
form. It merely suggest something other
than a singular inflationary big bang, and
offers an origin to dark energy, if that is
indeed present in this universe.

NubiWan
2002-May-18, 08:59 AM
Anyone here remember something called "the Ekpyrotic Universe ?" Its been around for 'bout a year, now. Suppose it would be considered a 'modified' inflation theory. Based on superstring theory, it addresses some of the "Big Bang" problems, such as monoploes, the tigger, and the singularity, to name a few. It was a 'Brane storm' out of Princeton, but haven't heard much follow-up about it...

John Kierein
2002-May-18, 11:03 AM
Steinhardt was on Art Bell Thursday night. He says the Universe cycles at orders of magnitude of trillions of years frequency, but only black holes survive a cycle.

One of these days they'll learn about the Compton effect red shift.

<font size=-1>[ This Message was edited by: John Kierein on 2002-05-18 07:05 ]</font>

rsa
2002-May-18, 01:03 PM
On 2002-05-18 04:59, NubiWan wrote:
Anyone here remember something called "the Ekpyrotic Universe ?
NubiWan, the Washington Post article linked to in the post just above yours is about the new cyclic version of the ekpyrotic model. There were a bunch of stories on this a few weeks ago.

One of the authors has more information on his webpage: http://feynman.princeton.edu/~steinh/

NubiWan
2002-May-19, 02:48 AM
Thanks for the heads-up, rsa, and your link. Hadn't heard of this "Cyclic Universe" before now. A rebirth of the old 'Steady State' model, who would have thunk it...

Firefox
2002-May-19, 03:28 AM
On 2002-05-18 07:03, John Kierein wrote:
Steinhardt was on Art Bell Thursday night. He says the Universe cycles at orders of magnitude of trillions of years frequency, but only black holes survive a cycle.

One of these days they'll learn about the Compton effect red shift.

<font size=-1>[ This Message was edited by: John Kierein on 2002-05-18 07:05 ]</font>


What if they learn the Compton Effect is totally wrong, one of these days?


-Adam

<font size=-1>[ This Message was edited by: Firefox on 2002-05-19 11:36 ]</font>

beskeptical
2002-May-19, 09:27 AM
OK, here's a really vague contribution. NPR's Science Friday, (Talk of the Nation), yesterday had an astronomer on, but I can't tell you his name nor credentials, (bad Beskeptical, no biscuit). He presented a non-big bang theory for the universe that had a component of a parallel universe. I really did not understand much of what was said and just when he started to talk about how to test for this parallel universe and this non-big bang theory, I had to leave. But I was really very intrigued and wonder who else might know more about it?

David Hall
2002-May-19, 11:45 AM
On 2002-05-19 05:27, beskeptical wrote:

He presented a non-big bang theory for the universe that had a component of a parallel universe.

It was probably the same ekpyrotic/brane theory mentioned just above. It's been getting a bit of press recently, so it's natural that NPR would want to discuss it.

It theorizes that instead of a singularity-based Big Bang, there was a collision of two three-dimensional "membranes", which caused a sort of Big Bang to happen in one of them, thus creating our universe. Periodic collisions could create a death/rebirth cycle similar to the old cyclic universe theory. The second membrane can also be theorized to have a continiuing effect on our universe, thus explaining the accelerating expansion that was discovered recently.

Check out that Washington Post article John posted above. It explains it pretty well.