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Comments (55)

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  myrmidon
  What I find really interesting is that black holes don't really "require" infinite density; the mass density inside the event horizon never exceeds neutron star levels, and becomes in fact lower the heavier the black hole gets (=> event horizon enclosed volume grows faster than mass).
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  rustyhancock
  One of the most remarkable aspects of physics is that Newtonian gravity calculations are quite spot on for all the parts of black holes layfolk consider important.1. Both predict the same critical radius, now called the Schwarzschild radius.2. Both predict a central singularity with formally infinite density in idealised collapse.3. Both predict exactly the same finite time to fall into the singularity under equivalent idealised conditions.4. Both give the same equation for radial free fall, using different definitions of time.What GR added was meaning to these things (and of course precise calculations outside of very idealised scenarios and symmetric conditions).
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  JohnKemeny
  Is it just me, or could they have added a, say, picture of a black hole?
• ck2
  there's a serious group of astrophysicists that actually disagree the photo was assembled properly at alllong paper made short I think their carefully demonstrated argument is it's a machine-learning hallucination to see what we wantDr. Becky has excellent coverage of it, will link it in a moment when I find ithere it is, well worth watching:* https://www.youtube.com/watch?v=9U6bvR6SzMoMiyoshi, Kito & Makino (2024; claim the Sag A* image is wrong)* https://academic.oup.com/mnras/article/534/4/3237/7660988
• tilt_error
  Well, for starters you need a reasonably long exposure time.
• metalman
  presumably the only way to get a good picture of a blackhole would be to get very lucky and catch a supernova going off next door, preferably at a slight oblique angle from one of the poles and be able to light the acretion disk and any dust but I dont think we have the visible light gathering capacity to search at the distances required for even a slight chance of capturing the event, so the answer to the question is : you wait.
• fuzzfactor
  Nothing beats a close-up.
• spottedmarley
  First you'll need a camera that can detect mathematical equations.
• ahmedk29
  [flagged]
• ethfan
  [flagged]
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  jon128
  They got an image of something, yeah.Or, did they? "So we had been perfecting these imaging algorithms on synthetic data. We’d fed these algorithms made-up data. So we would take a black hole image that we might be looking at. We’d corrupt it with noise, and we’d send it through these algorithms, and we’d refine these to the point where we were pretty confident in these algorithms." Algorithms? For what? So they're not just taking a photo of something observed through a telescope.They're not really explaining this either.I'm trying to keep an open mind but I'm still not buying the whole black hole thing.There needs to be something more intellectually compelling than "we know it's a black hole because we know it's a black hole".Yes, you read that right. I am doubting this religion. "That was a moment where there was a lot of crying and screaming." another odd quote from this article, provided one is assuming this is supposed to be around the scientific method.
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  monster_truck
  I'd use a camera, personally
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  lopsotronic
  Easy. Space isn't empty.Due to the insane distortion of "space"[1], every spare molecule in the vicinity is going to be lighting up at the speed of $E = mc^2$ . Which tends to be real visible. Black holes power some of the brightest things in the universe - light so powerful that it sometimes has its own gravity.A tame black hole is possibly the least fussy high-efficiency furnace imagineable. Of course, "tame black hole" possibly . . . isn't.[1] Whatever that happens to be, either bouncy rubber sheet or emergent property from deeper Hilbert Spaces or something beyond our imaginations. Or something that's just an illusion, an artifact of our specific perspective from our little spot in existence, like a rainbow.