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Astronomers Detect the Earliest Galaxies
FiReaNGeL writes "Astronomers, using NASA's Hubble Space Telescope, have uncovered a primordial population of compact and ultra-blue galaxies that have never been seen before. They are from 13 billion years ago, just 600 to 800 million years after the Big Bang. These newly found objects are crucial to understanding the evolutionary link between the birth of the first stars, the formation of the first galaxies, and the sequence of evolutionary events that resulted in the assembly of our Milky Way and the other 'mature' elliptical and majestic spiral galaxies in today's universe."
Old news!
I suspect I have identified such objects from submillimeter observations http://arxiv.org/abs/0802.1666 but it is very good to see a more robust population identified here.
Is 600 million years long enough to develop a complete galaxy? I'd think that might be too short for even a solor system to develop.
Who would win this election: Andrew Weiner vs Andrew Weiner's weiner.
How soon they form depend on your cosmological simulation. Something had to be forming to reionize the universe, but it did not have to be galaxies of a sufficient size that you would notice them. But, the further the existence of quasars was pushed back, the more you needed somewhat organized bodied in which they could form even earlier so there were indications that some massive galaxies form early.
http://media.aftenposten.no/archive/01011/SPACE-CHANDRA-NEBU_1011148x.jpg
My understanding of cosmology is at best limited, but shouldn't these galaxies appear red-shifted to the extreme? They are furthest and hence should be moving the away from us at an extremely fast pace. Is the name Ultra-blue restricted to element analysis based on spectrum? I'm just confused about the blue light.
You leave my wife out of this!
"Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
the characteristics of which coincide perfectly with the big bag theory.
Blah blah blah. Look, I don't want to hear about how observations matched predictions. That's not science.
It's like this: I don't understand Big Bang Theory, therefore I don't like it, therefore it's nonsense, therefore your "evidence" is really just your prejudice, therefore we're obviously going to find galaxies that are ten billion years older than these ones, and therefore my theory of the Giant Cosmic Bunny Orgy Theory, which is obvious if you even think about it rationally, will be proven correct once and for all and I'll be elected the President of Physics.
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According to TFA, hydrogen re-ionization when most of the universe was still opaque, gassy hydrogen and was not burning in the form of stars, blocks almost all of the light from 400 million to 900 million years after the BB. The only reason these galaxies were visible is because they believe they had extremely efficient hydrogen ionization, which is also why they were so blue. Before 400 million years post BB you have stars and galaxies only just forming, so I don't think there would be much in the way of light at all to be seen.
Also remember that the Big Bang is not an explosion in space, it's an explosion of space, so there might not be any visible light emmitted at all from the very beginning.
Security is mostly a superstition... Avoiding danger is no safer in the long run than outright exposure. - Helen Keller
The corresponding Hubble NewsCenter article includes more details and more, larger images.
Another way to look at it, is that at the instant before the big bang there was no universe, or you could say the universe was infinitely small. After the BB the universe was expanding, but there was still no space outside the universe. Everything we consider "space" is all packed inside the universe, and the universe was a lot smaller then than it is.
The classic analogy is the balloon analogy. Imagine three dimensional space is the two dimensional surface of a balloon with tiny points all over it representing matter. As the balloon expands, all points on the surface move away from each other, and the balloon has gotten larger. However, the center of the balloon is not on the 2d surface, the center of the balloon is in the 3rd dimension. Therefore, relative to the surface there is no center.
Now, bump everything up one dimension and you have our universe. The "surface" is three dimensional space, and it is expanding along the fourth dimension. We have no way of seeing the fourth dimension, just like a 2d creature on the surface of the balloon could do nothing but look forward, backward, left and right we can only do that plus up and down. We would need to add another dimension to our repertoir to view the fourth dimension, but we can't conceptualise beyond the abstract about what that might be. However, we can definitely see that everything in the third dimension is moving away from everything else. Therefore space is expanding, and no matter which way we look everything is moving away. In fact, no matter what vantage point you take in the universe it will always look the same, because the "surface" of the universe is what is expanding.
It's a bit mind numbing to think about, but there is no direction you can look at and figure out "where" the big bang was. There is no "where" in the third dimension, the where is in a dimension that we are not equipped to experience. All we can do is measure its effects in our own dimension.
I like Carl Sagan's explanation of the fourth dimension best, but wikipedia does a good job, if a bit on the technical side.
Security is mostly a superstition... Avoiding danger is no safer in the long run than outright exposure. - Helen Keller
This probably does not help much but the cosmological redshift is not from velocity but rather from space stretching along the path of the photon, which stretches the photon, increasing its wavelength.
As we observe objects at greater and greater distances, they have to keep revising their age-estimate of the universe.
And here we have spotted the farthest-away objects ever, and it required no revision of the age of the universe. There has been some adjustment towards 'older', but most of the time these days when the age of the universe is adjusted, it's towards more precision, not increasing age.
x can be UNEQUAL to y. So we can have infinite mass, distributed in an infinite volume, in a universe with neither beginning nor end.
Of course two infinite quantities can be unequal. Integers and real numbers are an obvious example. Unrelated, but the proof is more complicated, since multiplication is undefined for infinity. It's not a number.
while embracing a theory (which is no more than a belief, really, with a different authority appealed to)
Yeah, the authority of experimental evidence and verified predictions. If you think that there's nothing more to cosmological theory than some authority saying so from on high, then you're just not aware of how it came about.
They've changed the details of the story, but for some reason, it seems people just cannot manage to wrap their heads around the idea of there being something without a "before there was".
Actually physicists are quite readily able to wrap their head around something without a "before there was", and in fact a beginning-less universe was one of the leading theories when the Big Bang was first being proposed. It was only after the evidence came out strongly in favor of the Big Bang that the other theories began to fall out of favor. If theory is nothing more than belief from authority, then why was the "belief" du jour (which happens to be closer to your belief) abandoned? It wasn't overnight, either... A lot of scientists didn't like the idea at first.
However this doesn't mean astrophysicists have abandoned the idea of a universe with no beginning. The Big Bang Theory specifically does not make any predictions about what happened at or before the Bang. Some hypothesis are that the Big Bang is just one of many Bangs and the universe is repeatedly created/destroyed. Another is that the Big Bang was really just a collision between higher-order dimensions, and that many universes such as ours could have been created, even infinitely many. Still another is that space-time itself came into existence in the Big Bang, and therefore the concept of "before there was" is meaningless. Try wrapping your head around that!
The problem is there is no evidence for any of these hypothesis. So it is still very much up in the air. No authority is going to come down from the mount with a stone tablet and declare the answer. Whatever experiments you imagine they aren't "allowed" to conduct are being conducted, and the evidence will decide.
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The point was and is, just as when the Catholic Church was considered the guardian of all knowledge, (at least in Europe,) and an observation was made which pointed out that one of their stances was incorrect, (by being in direct contravention to what was observed,) they resisted, tormented those who disagreed, but ultimately had to revise their position when it became obvious they were wrong; so it is today.
And my counter point is that if the Church was Science, Copernicus and Galileo would have been heralded as heroes and revolutionaries because they had extensive and convincing evidence to support the heliocentric theory. Did you not read my post? The Big Bang Theory was such a revolution. It was not the favored theory, and only became so because of it's ridiculous success at making predictions that were later shown to be true! The reason physicists resist contention to such a theory is because there is so much evidence behind it, that it would take a great deal of truly surprising evidence to overturn it. But if you have a theory which produces such evidence, then your name will go down in history along with similar revolutionaries like Einstein, Heisenberg, Faraday, Young, etc.
Someone like me points out a theory has a problem, but that theory is so entrenched in the minds of its adherents that people try to shout him down, rather than listen, or instead make patronizing remarks.
Oh, and "those silly scientists, they don't understand infinity, or things without a beginning!" or "Big Bang Theory is just an appeal to authority", both of which are demonstrably untrue, isn't patronizing? Please! I'm patronizing you because you think that not understanding physics is a solid basis for insulting the intelligence and integrity of physicists everywhere. That deserves a patronizing tone.
The nice thing about science though, is that eventually, observation TRUMPS hypothesis, no matter how dearly cherished, so I don't really need to argue this point, I can simply wait.
And exactly WHAT observation leads you to believe that you're right? Oh, right, you're just sitting on your ass and waiting. You're not making any observations. You have no evidence for your theory. All the actual observational evidence points towards the Big Bang Theory being correct. You're just imagining and wishing that future observations will prove you right. Now who exactly is operating based on belief and dogma here?
Science is willing to accept that Big Bang Theory is wrong as long as compelling evidence comes along. Is your Church of the Ego willing to similarly accept this possibility? Or are you going to be sitting around your hole life, assuming you'll eventually be proven right?
You keep saying "observation triumphs", so you seem to be blissfully unaware of how observation has verified the current theory. If you really believed what you say, wouldn't that interest you?
Oh, and then there's the CMB. Interestingly enough, if that's radiant energy from the supposed "Bang", how exactly did the Earth get IN FRONT OF IT, for our radio-telescopes to be in position to intercept it? We'd have to be IN FRONT of the expanding sphere, or on the surface of the light-cone, as it were, to see it. This would require the matter which would one day become the Earth, to have travelled FASTER than light, wouldn't it?
Hehe. See, you don't even understand the CMB well enough to realize what's truly mind-boggling about it. It's not just that we can see this remnant of the Big Bang, it's that we see it roughly uniformly in all directions. So we aren't "in front of the expanding sphere", because then we'd see the CMB from only one direction and at once instant. Instead we're INSIDE the sphere in which the Big Bang took place, and the CMB emanated from all points in space and we're seeing the far reaches of it.
See, the Big Bang was not an explosion in space, it was an explosion of space.
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