7 ms·

That's not correct. Around 25% of the video is discussion around the concept of the radius of photon sphere to the event horizon, and what constitutes the light

That's not correct. Around 25% of the video is discussion around the concept of the radius of photon sphere to the event horizon, and what constitutes the light surrounding the photon sphere (one explanation he gives is that there are infinite reflections). Then he spends the last 30% of the video talking about reflections of the acretion disk. This is the theory that he never included in his original prediction, but doesn't explain why he made that call.

bdamm 8y ago
Uh.. It's the reason that the "shadow" is larger than the Schwarzschild radius. He's describing the ratio of the "rim" to the "hole". So while the picture may be fuzzy, there's information in it anyway about what the pictures means relative to how large/spin we think the black hole is. In fact I wish he'd said more about the Doppler effect.
- wallace_f 8y ago
  Ok I mean, now what you're writing, that's not even wrong. The black part of the image being larger than the actual radius of the blackhole is a discussion about the relative size of the black area you see in the image, to the actual black hole itself. I think that should make sense to you? It's not an argument about why he predicts it will look like a "fuzzy coffee stain," as opposed to other simulated images. Are you able to see the difference between those two ideas? I think you have some other discussion you were having confused with this one. To remind you about your earlier comment, you stated disagreement with me, saying this video was him only talking about why he predicted the image to look like a "fuzzy coffee stain" as opposed to some other simulated and theorized predicgions. I think the above paragraph and reply should obviously show you why this is actually not true. Are you still with me? I do think most of the video is interesting, but he never states an argument about why he chose that prediction. That was what I thought was ridiculous. Science is about reason and evidence, not just saying "believe me." Maybe you watched a different video? You should watch this video, the last 30% talks about simulations done in which the acretion disk reflects around the black hole, he uses example images which look a bit different!
  - darkpuma 8y ago
    The reason for the fuzziness should be obvious. It's really far away and it's really hard to see. Expecting a jump from "never seen before" to "seen in amazing visual clarity" is unrealistic.
    - wallace_f 8y ago
      That's also not even wrong. You can't see why? Let's say we're imagining what Uranus would look like. I draw a picture, and say it should look like a "fuzzy Jupter." But you ask, why should it look that way? Do you have a reason? And I say you should be confident, but don't provide an argument. By the end, I start talking about how it might look like Saturn. Then I come along and say, "it should be obvious the fuzziness is because it is far away." That final statement is not even wrong. It misses the point.
      - darkpuma 8y ago
        Are you upset that the Veritasium video didn't explicitly spell out for you that this black hole is very far away, so the first image of it ever is basically certain to be fuzzier than IMAX fidelity computer simulations used in a Hollywood movie? I think you're being very silly.
        wallace_f 8y ago
        What? You obviously didn't read what I wrote.
        darkpuma 8y ago
        > "What? You obviously didn't read what I wrote. Are you ok?" You're ranting about Saturn and Jupiter for some reason. Why don't you calm down and look at page eight of the paper that Veritasium video was based on: https://ve42.co/luminet https://ve42.co/luminet "Image of a spherical black hole with thin accretion disk Astronomy and Astrophysics, vol. 75, no. 1-2, May 1979, p. 228-235" Look at that last image, and squint at it until it gets fuzzy. Lo and behold, a fuzzy coffee mug stain! Perhaps it was a mistake for him to make the focus of the video on the physics of black holes, rather than the limitations of state of the art radio interferometry... but I don't think so.

bdamm 8y ago

Uh.. It's the reason that the "shadow" is larger than the Schwarzschild radius. He's describing the ratio of the "rim" to the "hole". So while the picture may be fuzzy, there's information in it anyway about what the pictures means relative to how large/spin we think the black hole is. In fact I wish he'd said more about the Doppler effect.

wallace_f 8y ago
Ok I mean, now what you're writing, that's not even wrong. The black part of the image being larger than the actual radius of the blackhole is a discussion about the relative size of the black area you see in the image, to the actual black hole itself. I think that should make sense to you? It's not an argument about why he predicts it will look like a "fuzzy coffee stain," as opposed to other simulated images. Are you able to see the difference between those two ideas? I think you have some other discussion you were having confused with this one. To remind you about your earlier comment, you stated disagreement with me, saying this video was him only talking about why he predicted the image to look like a "fuzzy coffee stain" as opposed to some other simulated and theorized predicgions. I think the above paragraph and reply should obviously show you why this is actually not true. Are you still with me? I do think most of the video is interesting, but he never states an argument about why he chose that prediction. That was what I thought was ridiculous. Science is about reason and evidence, not just saying "believe me." Maybe you watched a different video? You should watch this video, the last 30% talks about simulations done in which the acretion disk reflects around the black hole, he uses example images which look a bit different!
- darkpuma 8y ago
  The reason for the fuzziness should be obvious. It's really far away and it's really hard to see. Expecting a jump from "never seen before" to "seen in amazing visual clarity" is unrealistic.
  - wallace_f 8y ago
    That's also not even wrong. You can't see why? Let's say we're imagining what Uranus would look like. I draw a picture, and say it should look like a "fuzzy Jupter." But you ask, why should it look that way? Do you have a reason? And I say you should be confident, but don't provide an argument. By the end, I start talking about how it might look like Saturn. Then I come along and say, "it should be obvious the fuzziness is because it is far away." That final statement is not even wrong. It misses the point.
    - darkpuma 8y ago
      Are you upset that the Veritasium video didn't explicitly spell out for you that this black hole is very far away, so the first image of it ever is basically certain to be fuzzier than IMAX fidelity computer simulations used in a Hollywood movie? I think you're being very silly.
      - wallace_f 8y ago
        What? You obviously didn't read what I wrote.
        darkpuma 8y ago
        > "What? You obviously didn't read what I wrote. Are you ok?" You're ranting about Saturn and Jupiter for some reason. Why don't you calm down and look at page eight of the paper that Veritasium video was based on: https://ve42.co/luminet https://ve42.co/luminet "Image of a spherical black hole with thin accretion disk Astronomy and Astrophysics, vol. 75, no. 1-2, May 1979, p. 228-235" Look at that last image, and squint at it until it gets fuzzy. Lo and behold, a fuzzy coffee mug stain! Perhaps it was a mistake for him to make the focus of the video on the physics of black holes, rather than the limitations of state of the art radio interferometry... but I don't think so.