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BruceHinton
2001-Nov-27, 11:21 PM
Throughout many, (45 or so), years of passive absorption of astronomical learnedness from the ruminaries, -er-correction, -luminaries in the field, I am baffled by what I believe is a serious omission.
Why have I seen no mention of the increasing localization of "the observable universe" when looking at those 12-Billion-year-old-targets?
Seems to me that as we keep finding the newest "older than thine's" target, they should occupy a steadily decreasing angle of conical view that should obviously narrow to a point if someone should observe the very first star! Should be somewhere toward what we consider to be the center of the universe.
But then, to question again, has no sharpie considered that there could be an angular component to the origin of the (latest) "Big Bang", relative to us? Or the us we think we are?
Remember me, I would be interested in your feedback!........Bruce

Silas
2001-Nov-28, 03:20 AM
On 2001-11-27 18:21, BruceHinton wrote:
Throughout many, (45 or so), years of passive absorption of astronomical learnedness from the ruminaries, -er-correction, -luminaries in the field, I am baffled by what I believe is a serious omission.
Why have I seen no mention of the increasing localization of "the observable universe" when looking at those 12-Billion-year-old-targets?
Seems to me that as we keep finding the newest "older than thine's" target, they should occupy a steadily decreasing angle of conical view that should obviously narrow to a point if someone should observe the very first star! Should be somewhere toward what we consider to be the center of the universe.
But then, to question again, has no sharpie considered that there could be an angular component to the origin of the (latest) "Big Bang", relative to us? Or the us we think we are?
Remember me, I would be interested in your feedback!........Bruce


I'm just about the same age you are...

I am absolutely enraptured by the fact that, within my lifetime, the workings of the earth were revealed. (The mid-Atlantic ridge, leading to the concept of tectonic plates, leading to the understanding of subduction zones, etc...)

The idea of an "angular component" of the Big Bang seems odd... Our telescopes do not reveal any serious difference in the cosmos in any given direction...

Are you wondering what it might mean if the Big Bang had an intrinsic rotation? That would key in very directly to some other notions popular here...

Silas

Kaptain K
2001-Nov-28, 03:00 PM
Should be somewhere toward what we consider to be the center of the universe.

There is no "center of the universe". It is acentric and isotropic.

NubiWan
2001-Nov-28, 10:01 PM
On 2001-11-28 10:00, Kaptain K wrote:

Should be somewhere toward what we consider to be the center of the universe.

There is no "center of the universe". It is acentric and isotropic.




Me thinks he is referring to the "Observable Universe," which of course does have a 'center,' perhaps several of them. *L*


<font size=-1>[ This Message was edited by: NubiWan on 2001-11-28 17:02 ]</font>

<font size=-1>[ This Message was edited by: NubiWan on 2001-11-28 17:04 ]</font>

Mr. X
2001-Nov-28, 10:20 PM
On 2001-11-28 10:00, Kaptain K wrote:

Should be somewhere toward what we consider to be the center of the universe.

There is no "center of the universe". It is acentric and isotropic.


Sure there is, and it's me! /phpBB/images/smiles/icon_biggrin.gif
Witness EGOCENTRISM! /phpBB/images/smiles/icon_biggrin.gif

BruceHinton
2001-Nov-29, 12:28 AM
OK, so I had a little fun with the "center of the universe", (doesn't everyone know which way that is?), and the angular component of, (as seen from our unique location, not far from) the primordial seed as it flashes into the present universe. By Jove, it was moving up and to the right...

But I was serious about the directionality of the most ancient sightings. Should there not be an origination vector, in relation to the time/distance data that we judge them by?

Am I being romantic, (you know-like music of the spheres and that kind of romantic), to think we could be near the outer periphery of the "Big Ball"?

Bruce

Bob S.
2001-Nov-30, 05:25 PM
But I was serious about the directionality of the most ancient sightings. Should there not be an origination vector, in relation to the time/distance data that we judge them by?


Listen to Kaptain K. There is no physical center such as we would understand from our normal 3-D experiences. Actually, Mr. X is pretty close (though he was being humorous at the time). WE are at the center of our observable universe. In ANY direction you go, the further out you look, the older things are.

Think of it like this: take a ball. Where is the center of its surface? Not the center of the ball itself, but the center of the ball that you actually have contact with, the shell. Within its non-euclidean geometry, there is none.
In a similar way, all matter and space that we see exists on the "shell" of the expanding sphere of the universe, the center of that sphere existing not in space but in time.

Here's a link for a demo:
http://www.astro.ucla.edu/~wright/Balloon.html

On somewhat of a tangent, I've been wondering: is space sufficiently curved that if you took off in one direction, would you eventually end up back where you started? And how far would you have to go?
Ooo ooo! Brain cramp!

GrapesOfWrath
2001-Nov-30, 06:06 PM
Max Born, in his book Einstein's Theory of Relativity (my copy was published by Dover in 1962) wrote (p.364): "In a European observatory a certain star may be photographed; at the antipodes, say at Sydney in Australia, a star in the opposite direction may be observed. Then it is conceivable that in a spherical universe both observers actually see one and the same star--just as on the surface of the earth a wireless message from the antipodes, which follows the curvature of the globe, can reach us from opposite directions. It is even conceivable that the identitiy of the two star images can be established by some feature of the spectrum." The original book was written in 1920, but it was extensively updated in 1962.

Donnie B.
2001-Nov-30, 07:05 PM
Hmmm... does this question (whether you can travel back to your starting point by moving in a straight line along the cosmic equivalent of a great circle) connect to the open/closed question?

That is, must the universe be closed for this to be possible? If so, the empirical evidence suggests that it's impossible. However, I understand that the current best TOE's make the assumption that the universe is flat (just barely closed).

If the two things are connected, I think the answer would be, we don't yet know enough to answer the question.

Of course, there could still be other problems, if the expansion of spacetime is superluminal. That would make it impossible to complete the circle, since the space you're trying to cross is expanding faster than the maximum speed at which you can cross it.