311–320 of 525 posts
Basically, the image has been constructed by calculations on massive measurement data-sets from multiple synchronized telescopes around the world.
So this isn't a "photo" in the normal sense. It's a reconstruction of many, many radio waves.
100 billion kilometres wide, is that correct?
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I thought (relativistic) black holes were first predicted by Schwarzschild in 1916? (As an aside, I have found a whole extra level to nominative determinism since starting to learn German — Schwarzschild = Black shield)
It's a little of both, but yes Schwarzschild technically first predicted them. > In 1915, Albert Einstein developed his theory of general relativity, having earlier shown that gravity does influence light's motion. Only a few months later, Karl Schwarzschild found a solution to the Einstein field equations, which describes the gravitational field of a point mass and a spherical mass. https://en.wikipedia.org/wiki/Bla…
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editing that image reveals all kinds of details: https://imgur.com/a/TvQsgbA (and I don't even know what I'm doing)
Mind you, that's a JPG you are editing, so in the 8 bit sRGB color space. That means manipulations can lead to errors and illusions due to the color space being non-linear and clipped[0]. The original data was likely linear and at a much higher precision. If the source was a 16 bit linear grayscale PNG for example you could be much more assured you're not seeing the effects of JPG compression and things that were act…
Good video that correctly predicted the image and describes why it looks the way it does [1]. TL; DR The dark area is the entire surface of the event horizon, including the side facing away from us, plus some more due to photons missing the event horizon "directly" being drawn in. One side is brighter due to its being Doppler boosted. [1] https://www.youtube.com/watch?v=zUyH3XhpLTo
> Good video that correctly predicted the image and describes why it looks the way it does This is of course a bummer, since this means that the acquired image does not give us any new clues of where our understanding of physics is wrong.
Good video that correctly predicted the image and describes why it looks the way it does [1]. TL; DR The dark area is the entire surface of the event horizon, including the side facing away from us, plus some more due to photons missing the event horizon "directly" being drawn in. One side is brighter due to its being Doppler boosted. [1] https://www.youtube.com/watch?v=zUyH3XhpLTo
Not sure if I missed it, but can we tell which way the accretion disk is from our view of it?
Higher resolution official release seems to be: https://www.nsf.gov/news/special_reports/blackholes/download...
editing that image reveals all kinds of details: https://imgur.com/a/TvQsgbA (and I don't even know what I'm doing)
The papers with the scientific details are here (open access): https://iopscience.iop.org/journal/2041-8205/page/Focus_on_E... Article in physics world with comparisons to simulations: https://physicsworld.com/a/first-images-of-a-black-hole-unve... "AskScience" AMA on Reddit about the breakthrough: https://www.reddit.com/r/askscience/comments/bbknik/askscien...
From reddit: >"Hi, regarding the image itself: What I don't understand is why does it look like a donut and not a bright sphere? Assuming the black hole is actually spherical and not disc shaped, I would expect the Halo to be spherical and surrounding the black hole? so all we would see would be the ball of bright gas, even though there is a black hole in the middle?" This is also what I would have expected.
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A black hole itself (the singularity) is 1 dimensional - a single infinitesimal point. The event horizon around it is roughly a sphere. The diagrams that you are talking about are a visual metaphor that represent 3D space as a 2D plane and the 3rd dimension standing in for the influence of gravity. IRL, spacetime has 3 spatial dimensions, not 2, and gravity is not a dimension but a force. It's hard to visually repres…
I think you've got a typo here: points should be 0-dimensional.
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Relativistic beaming! https://youtu.be/zUyH3XhpLTo?t=490
So that would mean that the right side is tipped slightly away from us, right? Because the matter in the accretion disk starts approaching us at about halfway down the ring on the right side?
"Third, adopting an inclination of 17° between the approaching jet and the line of sight (Walker et al. 2018), the west orientation of the jet, and a corotating disk model, matter in the bottom part of the image is moving toward the observer (clockwise rotation as seen from Earth). "
