Hello there
The terminology of your question is rather confusing since you relate
things to an "out there" as opposed to what I must presume as the
location of Earth being "in here."
You say: "How did the ancient light source find the time to travel all
the distance from the initial point of the "Big Bang" to "out there"
(presumeably billions of light years from the initial point), before
producing light that required 14 bil. light years to reach us.
Well, for one thing it didn't wait till it got "out there" to begin
producing the light we see 14 billions years later. We are seeing the
light originating from where the source was 14 billions years ago and
that is from a spot near the "location" of the big bang.
Now, in cosmology, even the term "location" as we are using it here is
rather meaningless since all "location" is within the expanding
universe itself. When the universe was only one light year across
near the very beginning, then all "location" was within that globe one
light year in diameter.
So what we have to do is explore and define what is meant by relative
location. In relationship to the rest of the universe, the location
of the 14 billion year old light is in the same spot it was relative
to the rest of the "expanding" universe. It didn't go "out there"
someplace, the universe just got bigger.
Once again I will refer to the term "out there." It seems to denote
that the object somehow mover away from the "center of the universe"
or the location of the Big Bang.
"There no center of the universe because there is no edge of the
universe. In a finite universe, space is curved so that if you could
travel billions of light years in a straight line you would eventually
finish back where you started. It is also possible that our universe
is infinite. In both examples, groups of galaxies completely fill the
universe and are moving apart at all points making the universe
expand. There is no center to the expansion since the universe is
expanding from all points. The only answer to the question "Where did
the Big Bang happen?" is that it occured everywhere in the Universe."
You will find that fully explained and charted here:
http://www.anzwers.org/free/universe/bigbang.html - "The Big Bang and
the Expansion of the Universe"
Astronomers know that galaxies are rushing away from us, and the
farther away they are, the faster they are receding.
All the energy in the Universe was compressed into a tiny volume at
the instant of the Big Bang. By using the principles of physics,
cosmologists can estimate what conditions in the earliest Universe
were like. The younger the Universe, the smaller it was, the more
densely it was filled with energy, and the hotter it was. At about
.001 second after the Big Bang, the Universe had expanded and cooled
enough for neutrons and protons to form out of still more elementary
particles. At about 3 minutes, protons and neutrons could combine to
form stable nuclei. By about 500,000 years, the Universe was cool
enough for atoms to form.
The expansion of the Universe does not mean we are at the center. All
galaxies are receding from one another, and any observer on any galaxy
would see the same pattern we do. Astronomers use the "raisin bread"
analogy to explain the expansion. In raisin bread dough, the raisins
are close together. As the bread rises, the raisins spread apart, and
every raisin sees all the others receding. Dots on the surface of a
balloon would also illustrate the concept. As the balloon is
inflated, the dots on the surface all mjove away from each other. It
would make no difference on which dot you are standing, all the rest
would be moving away from you. However, each dot is still in the
relative location in relation to the other dots as they were before
the balloon expanded.
The Universe must be older than the Solar System, 4.6 billion years.
It must be old enough for light to have travelled from the most
distant objects we can see to reach us. Because it takes light a long
time to travel from distant galaxies to us, we see galaxies as they
were when light left them. When we look into space, we also look back
into time.
If we are seeing galaxies as they were billions of years ago when they
were once much closer to us, how can they look billions of light years
away? To answer this riddle, look at things from the perspective of
the other galaxy. Assume our galaxy is initially a billion light years
from another galaxy and the two are rushing apart at 90 per cent of
the speed of light. (see link list after the answer to learn how such
speed is determined and find out what is meant by the Hubble Constant)
Time = 0
New Galaxy Newly-formed Milky Way
@ @------>90% of speed of light
|-------| 1 billion light years
Time = 5 billion years
Galaxy Milky Way
@ |-------->@ has travelled 4.5 billion light years
Galaxies are 5.5 billion light years apart
@-------------> Light has travelled 5 billion light years and
is still 500 million light years from Milky Way
Time = 10 billion years
Galaxy Milky Way
@ |------------------------->@
Our galaxy has travelled 9 billion light years
Galaxies are 10 billion light years apart
@---------------------------------->
Light has travelled 10 billion light
years and is just arriving.
Thus, a galaxy that looks ten billion light years away really is ten
billion light years away. Its light has travelled ten billion light
years. However, the information carried by the light is also ten
billion years old, so we see the galaxy in the condition it was in
when the light left.
The chart above and much of the information is quoted from:
http://www.uwgb.edu/dutchs/CosmosNotes/cosmolgy.htm - Cosmology:
Structure, Origin and Fate of the Universe
I have made minor changes to the text as it was written before the
Hubble Telescope went into orbit. Such editing and paraphrasing does
not change the meaning and the material removed deals with predictions
of what the Hubble might find when launched.
Search - google
Terms - light speed, light speed and early universe, hubble constant
expanding universe
Websites used in the answer include:
http://curious.astro.cornell.edu/question.php?number=387 - "Curious
About Astronomy: How can the Universe expand faster than the speed of
light during inflation?"
http://www.anzwers.org/free/universe/bigbang.html - "The Big Bang and
the Expansion of the Universe" - A fascinating insight into the Big
Band and the expansion of the universe. Paragraph 7 in the answer
contains quoted material from this site.
http://zebu.uoregon.edu/~js/lectures/early_univ.html - "geometry of
expanding Universe, cosmological constants" - Here you will learn
about how the speed of the receding galaxies is determined. You will
find how the speed of 90% of the speed of light is determined for
galaxies one billion light years apart.
If I may clarify anything before you rate the answer, please ask.
Cheers
Digsalot |
Clarification of Answer by
digsalot-ga
on
18 May 2004 19:24 PDT
Hi again
I suppose the best thing to do would be to stick with the raisin bread
or dots on a balloon analogy.
Since we have established that the Big Bang didn't take place at a
specific place "within" the universe, but that the Big Bang 'is' the
universe itself and that the universe is expand equally from all
points rather than from a common center, then just as the dots on the
balloon, they no longer remain in any "center" but all rush away
equally.
Our discovery of that particular light source is not the discovery of
the original location of the Big Bang, it is merely the discovery of
one of the "raisins."
pgalswor-ga in his comment made reference to the faster than light
expansion of the universe - "Although the contents of the universe did
not move through space faster than the speed of light, space itself
expanded faster than the speed of light" - and there is also an
explanation for it in the
http://curious.astro.cornell.edu/question.php?number=387 - "Curious
About Astronomy: How can the Universe expand faster than the speed of
light during inflation?" link.
We need to realize that while this particular discovery was unique, it
will not remain that way long. It has been the case that after a
first discovery is made in cosmological sciences, others in the same
vein soon follow. The standard oldest objects known are quasars and
they are found regardless of which direction we look into the sky. So
they do not "cluster" around some particular point of origin but are
throughout all parts of the universe. That is, they are raisins
moving away from each other at tremendous speed.
These sources appear to stand alone because the entire universe IS
(caps for emphasis) their original clustering.
And you are right, light from those sources are not necessarily
galaxies. Many are what are known as proto-galaxies.
Most of the galaxies in the universe were formed long after the
original Big Bang and are made up of second, third or even later
generational material. By the time the Milky Way Galaxy (ours) was
formed, the universe was already almost ten billion years old. So
most all of the galaxies as we understand them, were not one of the
original raisins but formed in the spaces between the original raisins
and are much younger. Without using a math that may very well not be
understood by either of us, the reason we can not look for a cluster
of objects near where things began is simply because we are "within"
that cluster itself.
When the Big Bang was only an inch across, it was the entire universe.
There was nothing outside of it for it to expand "into."
Perhaps that is the cluster or location you are looking for. I think
that you think there is a way to look at the Big Bang from some place
that is outside the Big Bang. But such a place does not exist. We
can not observe the oldest parts of the universe from the outside
because there is no outside. Since we are within it, we are observing
that original 'cluster' expanding from its original location, in every
direction we look.
You state: "I do not have a specific answer and I suspect that such
does not presently exist...Why then does the 14 bil. light yr.
distant light source more or less stand alone and is not closely
surrounded by a multitide of similiarly distant and ancient light
sources, all near the original raisin group?
Yes, that specific answer does exist. That 14 billion year old light
IS closely surrounded by a multitide of similiarly distant and ancient
light sources, all 'relatively' near the original raisin group. That
multitude of similarly distent and ancient light sources is the entire
universe itself. And the reason we cannot see as such a 'cluster' is
because we, ourselves, are within that cluster, not someplace outside
looking back on it. That is why when we look out from Earth, the
stale raisins surround us rather than being clustered together near
some point of origin.
Now I know trying to explain such a thing in non-math terms is not
that easy to do nor is it always easy for another to understand in
many respects.
So, since the nature of this forum is that there can be a lot of text
placed here, feel free to keep asking for clarifications until we can
get it nailed down in layman's terms.
Some of the comments below want to delve into the math. But the
question didn't ask for a math type solution and I am trying to avoid
that.
Looking forward to the next clarification request.
Digs
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