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Astronomers Discover a Group of Quasars 4 Billion Light Years Across
New submitter mal0rd writes "NewScientist reports a 'collection of galaxies that is a whopping four billion light years long is the biggest cosmic structure ever seen. The group is roughly one-twentieth the diameter of the observable universe – big enough to challenge a principle dating back to Einstein, that, on large scales, the universe looks the same in every direction.' For reference, Andromeda is only 2.5 million light years away."
I've been wondering about that for some time. I can't tell if some astronomers really are clueless or if the disconnect is entirely at the level of the press trying to translate what an astronomer is saying. I've about come to the conclusion that many astronomers are very confused. They say "the early universe" as a matter of course, as if the distance the Hubble telescope can see is somehow relevant to the age of the universe. As you so succinctly point out, the universe can not possibly be a mere 13.5 billion years old. That's far far too little time to form what we see in our own backyard, let alone what we see in the little bubble Hubble can observe.
This quasar cluster, for example. Quasars are supposed to be super-massive black holes at the center of galaxies. That is, black holes of galactic mass. The articles haven't said very clearly just how far away the cluster is from us, but let's take the best case and say the Milky Way sits right on the edge of it. That makes the farthest reaches of it 4 billion light years away. Are they seriously claiming that a black hole on the far rim of the cluster from us could have absorbed an entire galaxy worth of mass in a mere 9.5 billion years? And that's just a bare minimum. Most probably the whole structure is much farther away from us than that, and therefore we're seeing it even farther in the past.
So this phrase we hear constantly is just nonsense. "The early universe." We haven't SEEN the early universe. Not even close. That 13.5 billion years is simply the lowest possible lower bound for the age of the universe. We understand precisely nothing about the cosmic background radiation that allegedly provides us with the most accurate current estimate. That estimate is based on a model that was force-fitted to previous guesses. It's crap.
Someday we'll have huge telescopes, far bigger than Hubble, orbiting in handy places like the Trojan points of Neptune and Saturn, and we'll be able to make some really USEFUL parallax measurements, and start clearing up some of the mess astronomers have accumulated by guessing too much with too little data.
"Standard candle" novas. Oh please...
It's not difficult to grow a 10^9 solar mass black hole in 10^9 years. Really the only hard part is getting the gas close enough to the BH to accrete; this problem and the hierarchical merger of black holes are active research areas.
Didn't you just make my point for me? "The only hard part." The only hard part is all the matter in a spiral galaxy spinning around its central black hole exactly once in 200 million years, without getting a helluva lot closer in all that time. And it appears from looking at the universe that that's the usual pattern. We don't see giant waterfalls of matter falling into black holes (at least not on galactic scales; on personal scales, just one star falling in is a giant waterfall; but I digress). We see loooong orbital falls. Really long, if the estimate of Sol's orbital period here in the Milky Way is even close to correct. So congratulations to Eddington for calculating an upper bound that is a very very long way from the actual average.
So how did the black hole get that massive to begin with? First it had to form. One black hole formation theory is the collapse of a super massive star. We'll dismiss that option, since it just makes the timeframe even longer—first you have to accrete a huge star, then it has to ignite, then it has to busily fuse hydrogen for umpty-ump million years, then it has to supernova and collapse. So we'll go with the other theory, that the Big Bang itself caused the formation of quantum black holes, right at the beginning, and those are what started galaxies, since they were first, and therefore got to suck up matter from the very beginning. Is there any reason to believe gravity behaved any differently in the early universe? No? Then those quantum black holes accreted matter the same way we see it happening today, damn slowly, with matter leisurely orbiting its way in. And since I'm feeling generous, we'll ignore the most recent math that shows there probably are no quantum black holes at all because it takes such a ridiculously long time for something that tiny to attract enough matter to grow that instead, it shrinks and ultimately evaporates, by Hawking Radiation. (Good thing for you the lifespan of a supermassive star is likely to be something deserve to be dismissed. For crying out loud, I'm sitting here wondering if your 10^12 solar masses number includes the alleged dark matter or not. The dark matter that should have been named Kludge Factor, because it's the label astrophysicists assigned for all the gravitationally interacting yet otherwise invisible "stuff" required to make one of your spiral galaxy simulations work. Meanwhile particle physicists wonder what the hell you're on about. Matter is baryonic or nothing. There is no magical Gravity Kludge Matter that fixes the model. There's something wrong with the model. There's something wrong with the last 100 years of astrophysics. Too much math done on far too little data.
And there's something wrong with guessing 13.75 billion years for the age of the universe.