Cool, now I have an intuition for how a black hole distorts lines of sight. Basically it's like a black ball hanging in space, with a "halo" that shows you a distorted image of everything that's behind the ball. For example, if there's a hula hoop around the ball, the near side of the hoop will look more or less normal to you, but the far side will look like it's warped, like it's refusing to go around the ball and instead shows up above or below it (or both). And the innermost part of the halo shows infinitely many images of the hoop (and everything else around the ball), stretched thinner and thinner.
Raytracing a Black Hole
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Re: Raytracing a Black Hole
#12I worked at dneg when this very shot was being rendered. From what I remeber there were a few steps to this being rendered, the first part was a massive particle sim. I was a systems engineer, so my job was to keep the system running. That particle sim ate at least 7, if not more hard disks. What ever it did, it destroyed 8tb HDDs. The worst part was we couldn't take that file server offline, as the render needed to…
AFAICT the parent comment is referring to Double Negative (dneg). The visual effects company responsible for the black hole shots in the movie Interstellar.
Re: Raytracing a Black Hole
#13I had never thought about it but in a sense black holes work as a mirror. Some light will sling shot around the back of the hole and back in the opposite direction.
You always get some back scatter from a glass surface, so any magnifying glass is much more like a mirror than a black hole.
Re: Raytracing a Black Hole
#14And in the coming years astronomers hope to image a black hole directly (in radio wavelengths). The few closest supermassive black holes (in center of galaxies) have their event horizon angular diameters just big enough to be resolved by VLBI (very-long-baseline interferometry). See [3] for details and a simulated image.
[1] https://en.wikipedia.org/wiki/Event_Horizon_Telescope
[2] https://eventhorizontelescope.org/
[3] Seeing Black Holes: from the Computer to the Telescope (https://arxiv.org/pdf/1804.03909.pdf)
Re: Raytracing a Black Hole
#15This is pretty awesome to see since I did something related to this to simulate gravitational lensing around black holes back in 2000 under the guidance of Ronen Plesser at Duke University. Back then however, the computing resources I had available were far more primitive and I can't even imagine how long it would have taken me to render something like this back then. That said, this is way more advanced than what I was doing as well.
Re: Raytracing a Black Hole
#16I worked at dneg when this very shot was being rendered. From what I remeber there were a few steps to this being rendered, the first part was a massive particle sim. I was a systems engineer, so my job was to keep the system running. That particle sim ate at least 7, if not more hard disks. What ever it did, it destroyed 8tb HDDs. The worst part was we couldn't take that file server offline, as the render needed to…
I so love this kind of behind the scene story
Re: Raytracing a Black Hole
#17Re: Raytracing a Black Hole
#18Re: Raytracing a Black Hole
#19And in the coming years astronomers hope to image a black hole directly (in radio wavelengths). The few closest supermassive black holes (in center of galaxies) have their event horizon angular diameters just big enough to be resolved by VLBI (very-long-baseline interferometry). See [3] for details and a simulated image. [1] https://en.wikipedia.org/wiki/Event_Horizon_Telescope [2] https://eventhorizontelescope.org/…
I believe this is supposed to happen this year, last I heard was this summer but they haven't finished the analysis yet. The data was collected back in April, petabytes of harddrives flown to a central processing location.
Re: Raytracing a Black Hole
#20I worked at dneg when this very shot was being rendered. From what I remeber there were a few steps to this being rendered, the first part was a massive particle sim. I was a systems engineer, so my job was to keep the system running. That particle sim ate at least 7, if not more hard disks. What ever it did, it destroyed 8tb HDDs. The worst part was we couldn't take that file server offline, as the render needed to…
Sometimes I think about what kind of yak shaving it takes to put together some menial technical detail, and I just throw the idea out, if it doesn't feel like the implementation is clean enough.
If someone told me that in order to take a picture of some natural landscape, I'd have to throw 7 brand new 8TB hard drives in the garbage, in order to capture a 64 megapixel image, I'd say "not worth it."
It challenges one's natural disinclination towards waste. I think that's a pretty normal gut response. Gifted with an a priori awareness of certainty of return on investment, it makes sense dive in, get knee deep, ignore the intuition that wells up around thoughts of sunk cost fallacies, and push through the hard parts. But when you're not a fortune teller, that risk aversion tends to help, more than harm.
But, you know, maybe that's the kind of thing that separates people like me from true success.