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Fraser
2005-Mar-09, 08:48 PM
SUMMARY: It appears that galaxies in the early Universe didn't evolve at similar speeds or in the same ways. Almost right from the beginning, the Universe was filled with galaxies large and small, dusty and clear, active with star formation and relatively sedate. Researchers from the US used Infrared Array Camera (IRAC) aboard NASA's Spitzer Space Telescope to study galaxies 10-12 billion light-years away. Instead of finding a similar set of galaxies, they turned up tremendous varieties, as much as we see in the night sky today.

View full article (http://www.universetoday.com/am/publish/galaxies_early_universe.html)

What do you think about this story? Post your comments below.

Guest
2005-Mar-09, 10:13 PM
From the article:


The team was particularly surprised to find a curious breed of galaxy never seen before at such an early stage in the universe--old, red galaxies that had stopped forming new stars altogether. Those galaxies had rapidly formed large numbers of stars much earlier in the universe's history, raising the question of what caused them to "die" so soon.

Oh well, is anyone wondering if maybe we are living in a Steady State Universe instead of a Big Bang Universe?

Cheers.

400poundgorilla
2005-Mar-10, 12:07 AM
I believe that I posted a reply to a similar thread elsewhere where I was curious to know more about how they are now speculating on galaxies arriving at full maturity so early. I also postulated that perhaps the universe is much older that we currently believe.

Maybe this should go under alternative theories, but here's a chilling thought that a particular song made me think of. The lyric goes... Could I believe that what I saw that night was just a reflection of my warped mind staring back at me? I know this sounds crazy, but has anybody taken a close look at some of these most distant galaxies to see if they might actually be reflections of much closer galaxies? :ph34r:

Guest
2005-Mar-10, 11:06 AM
Is there any way we can see our own Milky Way
12 billion years ago.?
If so are we simply looking at ourseves as we are now, maybe?
Steve

antoniseb
2005-Mar-10, 11:50 AM
Originally posted by Guest@Mar 9 2005, 10:13 PM
Oh well, is anyone wondering if maybe we are living in a Steady State Universe instead of a Big Bang Universe?
Not me. It would take less than a billion years for a galaxy to start being predominently red after its sta-forming dust and gases had been swept out. There's no reason that there couldn't be many such galaxies within 1.5 billion years of the big bang. The ones observed in this study are older than that.

antoniseb
2005-Mar-10, 11:52 AM
Originally posted by Guest@Mar 10 2005, 11:06 AM
Is there any way we can see our own Milky Way
12 billion years ago.?
No way to do this is known or expected to be discovered.

lswinford
2005-Mar-10, 02:19 PM
'Curiouser and curiouser'...hmm...maybe that book with the six days thing has something, assuming we get some really looong days, but then maybe we've got all kinds of yardsticks out of whack. I just love it when things are uncovered and textbooks get to be rewritten. I've some on my shelf from the '40s and '50s that are worth a snort and a giggle from time to time. Maybe in a few years I'll have some more that will contain a few chuckles that aren't so old and dusty. Keep those fun new facts coming. :rolleyes:

Khanh
2005-Mar-10, 04:45 PM
Hey everybody, the tested theory of general relativity says time is not absolute. So when scientists say a 15 billion years old universe, what clock is referred to?
It was a long time ago these years and age of the universe bother me. removed affirmation of religious belief and reference to a particular creation story - antoniseb

BIG BANG is a theory guys.
Have a good day!

400poundgorilla
2005-Mar-10, 06:23 PM
Khanh,

The whole purpose of Science is to "know" things. This is done through guesses, tests, and analysis that ultimately reveal truth. Religious fundamentalism has no place in this type of discussion because by nature fundamentalists see any other viewpoint as the antithesis to their beliefs. The scientific community may have many theories, but generally each camp at least remains open to the possibility that another theory may be the correct one. This even includes intelligent design.

Five thousand years ago, if I had been in a position to be thought of as a prophet and I had written that Darth Vader created the universe with a wave of his light saber in a split second, there would be people today that would claim to "know" this is the way things happened simply because that was what written. Science only wants to know the truth. :(

You're entitled to your view Khanh, but I'm from a background that had that same book fed to me on a daily basis. I constantly asked "why?" "how?" I have found science answers those quesitons better than religion. Thanks for the well wishes though. You have a good day too. :)

dave_f
2005-Mar-11, 01:59 AM
Originally posted by Khanh@Mar 10 2005, 11:45 AM
Hey everybody, the tested theory of general relativity says time is not absolute. So when scientists say a 15 billion years old universe, what clock is referred to?
It was a long time ago these years and age of the universe bother me... BIG BANG is a theory guys.
Have a good day!
I can see where you're going with the logic here. What your explanation does address though is the how. Think of it this way: there's a broken plate next to the table on the floor in several pieces. Now, as a detective, you look at the plate and are charged wtih coming up with an explanation. Here's the two possible conclusions you can come up with:

1) removed religious reference
2) Someone accidentally pushed the plate off the table resulting in it shattering into several large pieces on the floor.

Now, someone with your point of view might regard both these statements as truth, either way (the first one particularly). But the first statement does nothing to determine who exactly needs to pay for a new plate. Also, if I hired a detective to find out who broke the plate and he came back saying removed religious reference, he would be one unemployed detective in a very short amount of time.

And by the way, I'd like you to refer to the technical definition of the word "theory" in the scientific sense (from http://answers.com/):

theory (thē'ə-rē, thr'ē) pronunciation
n., pl. -ries.

1. A set of statements or principles devised to explain a group of facts or phenomena, especially one that has been repeatedly tested or is widely accepted and can be used to make predictions about natural phenomena.

antoniseb
2005-Mar-11, 08:45 AM
Hi Folks,

I've had to modify some of the posts in this thread. Newer people should be aware that we do not discuss religion or politics in this forum (according to rule 7). This is a first violation for Khanh, and so no one is angry about this, but please, in the future, stay away from religion, and stick with what is observable more objectively.

GOURDHEAD
2005-Mar-11, 02:00 PM
Is there any way we can see our own Milky Way 12 billion years ago.?
Not unless quantum entanglement can be applied by one skilled in its use and this one is appropriately located to be currently in position to observe the MW as it was 12 billion years ago and had sent a message with appropriate lead time that can be modified via quantum entanglement to provide the desired image. [I neither believe in quantum entanglement nor that anyone can be so skilled.]

The Near-Sighted Astronomer
2005-Mar-15, 06:48 PM
Hi All,

Here's a little publicized fact: The formula astronomers use to convert redshift to distance-time looks like this:

t = (z/1+z)*13.7

where t is amount of time since the light was emitted
z equals the degree of redshift where 0 = "none"
and 13.7 is the age of the universe in (billions of years.

so say a galaxy displays a redshift of "1" the resulting time since emanation equals 1/2 * 13.7 = 6.85 billion years ago.

Does anybody else see a problem with this? (There's probably more than one!)

Issue: Assume the Big Bang spread matter out spherically (a flat universe). What would the redshift be of a galaxy whose light was emitted from the far hemisphere of the expanding universe?

You can't calculate it and therefore you'd never know you were seeing such a galaxy. (Go ahead plug in a redshift of 100 what do you get?)

So here's the bottom line Those "thoroughly modern galaxies" could (for all we know) be at a time-distance greater than 13.7 BLYs.

Cheers,

jeff

The Near-Sighted Astronomer
2005-Mar-15, 06:52 PM
Oh Yah,

As for "Could we ever see light from our own galaxy?"

Sure but it would be "incoherent" (scattered light) that could not give us any image of its source. Why? Because that light would have to have been "bounced around" the Universe on a crazy quilt path by encountering free electron clouds in space.

We can never see our own light directly because the universe is not "gravitationally bound" - if it had been so bound then we would not be living in an "inflating universe" but one that would be "deflating" (losing expansionary rate over time...

(Any cosmologists out there would you please contact me for an article discussing these last two posts of mine?)

jeff

scorpio711
2005-Mar-15, 10:08 PM
Jeff,
I think your formula is only applicable when z is much smaller than 1. As soon as z becomes close to 1, you need to use the formula:
v = c * [(z+1)**2 -1] / [(z+1)**2 +1], v being the velocity of the far object and z the usual Delta lambda/lambda.
You get the time by inverting the formula.
Here are some references:
http://www.earth.uni.edu/~morgan/astro/cou...on3/math13.html (http://www.earth.uni.edu/~morgan/astro/course/Notes/section3/math13.html)
http://www.olduniverse.com/appendix_g.htm
where you can find the relativistic formula for z. Also read:
http://cas.sdss.org/dr3/en/proj/advanced/h...e/redshifts.asp (http://cas.sdss.org/dr3/en/proj/advanced/hubble/redshifts.asp)
and interesting comments also in:
http://www2.corepower.com:8080/~relfaq/exp...g_universe.html (http://www2.corepower.com:8080/~relfaq/expanding_universe.html)

Hope this helps,
Scorpio

The Near-Sighted Astronomer
2005-Mar-16, 01:17 AM
Thanks Scorpio,

I grabbed the formula off one site or another - it isn't relativistic but comes close.

However, not having looked over the new formula, but is it really any better at dealing with redshifts caused by being on "the far side"?

Thanks a bunch,

jeff

vet
2005-Mar-16, 05:12 AM
Originally posted by Guest@Mar 9 2005, 10:13 PM
From the article:


The team was particularly surprised to find a curious breed of galaxy never seen before at such an early stage in the universe--old, red galaxies that had stopped forming new stars altogether. Those galaxies had rapidly formed large numbers of stars much earlier in the universe's history, raising the question of what caused them to "die" so soon.

Oh well, is anyone wondering if maybe we are living in a Steady State Universe instead of a Big Bang Universe?

Cheers.
the string-theory multiverse is a 'constant state universe'---but one where 'newness' is not restrained, so as we clearly have seen 'quantum-fluctuations' as continuous 'pop-ups', so it is with discrete multiverse 'emergents'---
what is the source? that's termed 'initial conditions', and best left to meta-physics.
and in that realm, oddly, the West Coast USA aboroginies have soundly 'whupped' all comers.

a student of 'Nagualism' is taught that even a multiverse is just one more piece of 'table-ware'---familiar and 'wordable', to them just one 'set-point' in an infinite set, whose points are so diverse, there is No commonality. None. when one enters such a set-point, it quickly obscures your 'initial conditions' source, adobting the rules of the set. 'initial conditions'? beyond all of these sets? they term that 'that for which there are no words'. driven by some way to grapple with that, they decided to term it The Nagual. this happened perhaps tens of thousands of years ago, as Nagualism, by petroglyph, appears the oldest view of the universe known.

not a religion, cosmology on a quantum level---the truly interesting aspect is that one may use this 'usually invisible' part from which a specific 'set' springs, make it do 'work', in the 'now'. the concept has become a circus of thieves---one book, "Tales of Power' elucidates all---after that the author obviously 'sold-out'---those Malibu mansions cost plenty---so don't waste time.

it's a mind-bender even attempting to imagine any 'place' as solid, real as now---yet so different there are no common words---but coming to such place, after a bit, as here, all would seem as ALL. even the multiverse. even Life. so what?

looking even at 'death-by-time', this place could use some fixing---evolving---i suspect it a new universe, highly similar, but less of 'the horror', bubbling forth from the now, and laying the 'then' to rest. the only question is 'how'? i may answer that---

vet
2005-Mar-16, 05:50 AM
well, universe age is based on 're-winding' to zero---as a child in tampa, fla., we often swam at a resort---it had a 6 meter or so wall 50 meter circular shell, fed by an artesian well at center', with an outout channel for the 'over-run'---water swiftly moved outwards from the central 'cave's' output---

if one were to measure the doppler shifts of water molecules moving further from the source, they would be red-shifted, but still be the same age. and the 'spill-way' so many children enjoyed? were we at the bootom, looking back, we might see an origin, whose red-shift character would vary, as velocity, from that encountered in the main source. so what do we really know? not much.

mutilator
2005-Mar-23, 01:23 PM
What I find most interesting is the inability of the 'scientific mind' to see that any theory is a religious concept. All theory is based in faith. Despite what evidence you believe you have, it is the interpretation of said evidence that gives you your theory. When, in times past, people saw the majesty of nature, they developed theories to explain their universe. Once these theories were accepted, they became 'truth'. Accepted science says that the Universe is X years old, but the truth is, that it is only a theory. No matter how complex the math. You only have to see the debate that has raged for the last 60 to 80 years, covering relativity, string theory, quantum theory etc. Please stop pretending we know. The truth is that we are still wondering. It would also seem to me that an old galaxy is an old galaxy, even if that doesn't fit the 'established truth' that is being preached in the sacred halls of science. Please don't miss-understand, I believe that we should keep seeking, my only problem is the jump to conclusion.

antoniseb
2005-Mar-24, 03:53 PM
Originally posted by mutilator@Mar 23 2005, 01:23 PM
my only problem is the jump to conclusion.
If you examine what is written in the scientific papers, as opposed to the simpler and more accessible articles in magazines, and web-journals, you will see that these theories are not assumed true, and are not built on faith. Further, they are constantly tested. The taking it on faith you speak of is not on the part of the scientists.

VanderL
2005-Mar-24, 08:29 PM
QUOTE (Guest @ Mar 9 2005, 10:13 PM)
Oh well, is anyone wondering if maybe we are living in a Steady State Universe instead of a Big Bang Universe?

Antoniseb:
Not me. It would take less than a billion years for a galaxy to start being predominently red after its sta-forming dust and gases had been swept out. There's no reason that there couldn't be many such galaxies within 1.5 billion years of the big bang. The ones observed in this study are older than that.


Sorry, that was me back there, what makes you say it would take less than 1 billion years for a galaxy to "mature"? And at what point do you think the Big Bang theory is untenable? In my opinion we're awfully close already.

Cheers.

antoniseb
2005-Mar-24, 10:23 PM
Originally posted by VanderL@Mar 24 2005, 08:29 PM
at what point do you think the Big Bang theory is untenable? In my opinion we're awfully close already.
There are many social subjects where I share your opinion, but on this issue we are miles apart. All the big bang theory says is that the universe is expanding, and seems to have a single date at which you can extrapolate that everything we see was in one place (about 13.7 billion years ago).

You think other explanations for the evidence we see as expansion are valid.

For me to think that the Big Bang theory is untenable, I would have to see evidence that none of the galaxies we see having cosmic redshift are actually getting further away from us. It might be possible within the next 30 years to get a sufficiently accurate parallax measurement to M87's central SMBH that within another twenty years we could actually measure an increase in distance from this object.

M87 is roughly 20 megaparsecs away, and using BBT expansion is going away from us at about 1400 km/sec, this would be about a tenth of a lightyear further away every twenty years. Using Solar-System wide optical interferomtry and the Sun's motion around the milky way as a base for paralax, we should be able to measure the distance accurately enough to see this movement.

If M87 is not moving close to that speed away from us then I'll take that as a sign that there is something other than universal expansion causing this redshift we see.