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Astronomers Discover 83 Supermassive Black Holes at the Edge of the Universe (cnet.com)
"A team of international astronomers have been hunting for ancient, supermassive black holes -- and they've hit the motherlode, discovering 83 previously unknown quasars," reports CNET:
The Japanese team turned the ultra-powerful "Hyper Suprime-Cam", mounted to the Subaru Telescope in Hawaii, toward the cosmos' darkest corners, surveying the sky over a period of five years. By studying the snapshots, they've been able to pick potential quasar candidates out of the dark. Notably, their method of probing populations of supermassive black holes that are similar in size to the ones we see in today's universe, has given us a window into their origins.
After identifying 83 potential candidates, the team used a suite of international telescopes to confirm their findings. The quasars they've plucked out are from the very early universe, about 13 billion light years away. Practically, that means the researchers are looking into the past, at objects form less than a billion years after the Big Bang. "It is remarkable that such massive dense objects were able to form so soon after the Big Bang," said Michael Strauss, who co-authored the paper, in a press release. Scientists aren't sure how black holes formed in the early universe, so being able to detect them this far back in time provides new avenues of exploration.
After identifying 83 potential candidates, the team used a suite of international telescopes to confirm their findings. The quasars they've plucked out are from the very early universe, about 13 billion light years away. Practically, that means the researchers are looking into the past, at objects form less than a billion years after the Big Bang. "It is remarkable that such massive dense objects were able to form so soon after the Big Bang," said Michael Strauss, who co-authored the paper, in a press release. Scientists aren't sure how black holes formed in the early universe, so being able to detect them this far back in time provides new avenues of exploration.
I think they mean, edge of the observable universe.
It's always the way, innit? You hang around for three million years in deep space and there hasn't been one, then all of a sudden eighty three turn up at once.
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Ah the old brilliant line of "I'm dumb, therefore no-one else can know anything".
replying to myself -
No, because these object are closer than the cosmic radiation background, so are in fact "inside our sphere".
If these (and millions more) are hard to see, and have large amounts of gravity, could it be that they're what's causing the universe to expand quicker than expected?
Doctors often engage in "I went to school, therefore no one else can know anything".
BTW what's with that hyphen??
"Scientists aren't sure how black holes formed in the early universe, so being able to detect them this far back in time provides new avenues of exploration."
A nice departure from the hyperbolic "Scientists are shocked to find...." or "Scientists scramble to find answers when the laws of physics are turned on their head!" sort of wording.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
replying to myself -
No, because these object are closer than the cosmic radiation background, so are in fact "inside our sphere".
But if they're on the edges, perhaps they are the "doors" to the other universes. Kind of like the doors to other holiday lands in the forest in Nightmare Before Christmas
The only thing necessary for evil to triumph is for it to be pitted against a slightly greater evil
Light scatters in all directions (for the most part) from the origin of a single point of event.
No, a photon will travel in a straight line from it's point of origin unless acted upon by an outside force. You are describing what happens to the innumerable photons that are emitted from a typical light source which is not the same thing. The photons that we see from these distant sources have traveled a long distance in a straight line (*) to get to us.
(* straight in this context is not the same Euclidean geometry straight line you might have learned about in high school)
So if it happened 13 billions year ago, how is it still observable?
Because the universe expanded faster than the speed of light. Space itself is expanding to this day and so some light that was emitted a long time ago is just now reaching us. Some light that was emitted a long time ago will never reach us because it's too far away and space is expanding too fast for it to ever get to us.
These are not mutually exclusive ideas, and your point is irrelevant.
The hypen is correct in British English, which is my native language. It also disambiguates between a singular entity (e.g. "There are four men in a room. No one can lift the boulder.") a mass ("No-one knows how many piano tuners there are in Europe.")
There is no convincing evidence that you exist, either.
From the photon point of view, there is no time, all path are instantaneous, short (human size) or astronomical (accross the observable universe), for the photon it ages exactly a perfectly zero seconds.
I accept this as apparently factual. What I'm having trouble wrapping my brain around is the relationship between the statement above and how photons travel through spacetime if they do not experience time. Speed = distance / time and photons have the constant speed = c. But if time for them = 0 then that fundamental mathematical relationship breaks down and is undefined. (cannot divide by zero but we are essentially saying c=dist/0) My confusion is, how does a photon travel a distance through spacetime non-instantly (which it clearly does) if it does not experience time? Photons travel at a fixed rate through spacetime which is demonstrably not infinite and has time in the definition of that rate.
I expect the answer to be some non-intuitive reference frame of the observer sort of answer or something about velocities in spacetime (as opposed to space) being constant but I can't seem to puzzle it out.
I like to think that no matter where you are, or when, or who, you are always at the exact center of the universe. Because that's a true fact.
What is the challenge in understanding early blackhole formation?
If energy coalesced into enough matter that was close enough to other matter, wouldn't that be enough g to create a mass that collapses on itself?
Shouldn't need a supernova to do that, right?
And one restaurant.
Time was, people had grave difficulties with theology of God-as-deceiver, described in the question of did Adam and Eve have belly buttons.
If so, it indicated a past that never actually happened. If not, then they weren't in the image of God, of which Man in general is.
Modern theology that tries to get around the vast size of the universe by suggesting God created space witb light from stars already 99.999% of the way here, suffers the same problem.
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
Seventy comments and no one has thought to post this? What's happened to Slashdot?
https://youtu.be/N-_mHedypEU
You are welcome on my lawn.
A photon as a particle will travel in a straight line as you classically think, however it is also a wave and has uncertainty according to Heisenberg uncertainty.
This is true but not relevant to this particular discussion. A photon from Betelgeuse does not diffuse to both Alpha Centauri and our Sun in any practical sense. It's not a useful exercise to treat the uncertainty in the position of a photon in units of light years. Remember we are talking about photons we've actually observed through our eyes or through out measuring equipment.
If you constrain the photons position, say by emitting it from a point and passing it through an arbitrarily small orifice, cementing position, momentum blows up and spreads it out.
It doesn't spread out to distances measured in light years. And we are constraining the photon's position because we have observed it.
Black hole evaporation is extremely slow via Hawking radiation. It's less on the order of billions of years and more on the order 1 followed by a billion zeros. Gravitational interactions don't preference older or younger objects, more denser and heavier objects are drawn inward as momentum is transferred to the lighter mass object.