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Show HN: Physically accurate black hole you can put in your room

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Re: Show HN: Physically accurate black hole you can put in your room

#121

Post by reactordev »

vee-kay wrote: post #96
KaiserPro wrote: post #83

Earlier quoted context omitted.

I clicked on this because I worked on the infra that simulated the famous blackhole sim in interstella. I thought "oooh this is interesting I wonder how they are going to do physically accurate on an end device" Recalling how the original particle sim was something like 100TB, took 2 weeks to generate and seemed to write in a way that killed disks. but that was >10 years ago, so what clever stuff has been done to mod…

Someone refers to a sci-fi-esque (more imaginative than scientifically accurate) virtual rendition of an interesting scientific phenomenon (black hole) in a fanous sci-fi movie (Interstellar), in their scientific analysis/critique comment on a HN thread about the virtual sci-fi-esque rentition of such a sci-fi object (black hole)(yes, a simplified easy-on-eyes pseudo-accurate rendition of a black hole, for VR/AR imme…

You have reached the end of the internet. We hope you enjoyed your stay. /s

Re: Show HN: Physically accurate black hole you can put in your room

#122

Post by gilrain »

biorach wrote: post #97
20k wrote: post #34

If anyone's interested in the accuracy, this is very 'visualisation grade' software. Its a bit of a pet peeve of mine that people present these sims as being very physically accurate, when they contain major inaccuracies, some of which are very obvious and/or deliberate. This one has some serious physical limitations I wouldn't mind at all if it didn't say that this was a *physically accurate* black hole specifically…

I think you're being very harsh. I read it as a side project of a scientist meant to entertain as much as educate. Holding it to the same standards as the Event Horizon project seems pedantic and excessive.

The person you’re replying to did not hold it to that standard — they only pointed out that the standard it claimed to hold itself to was not actual.

If correcting misinformation is “harsh”, reality is fucked.

Re: Show HN: Physically accurate black hole you can put in your room

#123

Post by gilrain »

FrustratedMonky wrote: post #118
20k wrote: post #34

If anyone's interested in the accuracy, this is very 'visualisation grade' software. Its a bit of a pet peeve of mine that people present these sims as being very physically accurate, when they contain major inaccuracies, some of which are very obvious and/or deliberate. This one has some serious physical limitations I wouldn't mind at all if it didn't say that this was a *physically accurate* black hole specifically…

"an astrophysicist at Harvard's Black Hole Initiative" He probably knows. It's in a browser, there are probably some trade-offs. Calm down.

Keep your need for simplified representations of reality (which claim to be complete) out of our information-based community.

Re: Show HN: Physically accurate black hole you can put in your room

#124

Post by gilrain »

aplavin wrote: post #37
20k wrote: post #34

If anyone's interested in the accuracy, this is very 'visualisation grade' software. Its a bit of a pet peeve of mine that people present these sims as being very physically accurate, when they contain major inaccuracies, some of which are very obvious and/or deliberate. This one has some serious physical limitations I wouldn't mind at all if it didn't say that this was a *physically accurate* black hole specifically…

Some are fair – of course this is a simplified visualization! Observationally, we don't really know how fast a given black hole is rotating, and here I indeed assumed a non-rotating one. It's not an inaccuracy per se, more like a missing feature. The camera mode has a (half-hidden) toggle to enable Kerr metric and set spin, but even there it's not a default. I consider the colormap choice to be completely arbitrary t…

> completely arbitrary

You agree that it isn’t “physically accurate”, then… but seem to argue that you shouldn’t be called out for the false title?

It’s fair enough to be called clickbait when you really did score extra clicks with a slick falsehood, surely?

Re: Show HN: Physically accurate black hole you can put in your room

#125

Post by FrustratedMonky »

gilrain wrote: post #123
FrustratedMonky wrote: post #118

Earlier quoted context omitted.

"an astrophysicist at Harvard's Black Hole Initiative" He probably knows. It's in a browser, there are probably some trade-offs. Calm down.

Keep your need for simplified representations of reality (which claim to be complete) out of our information-based community.

Running a simulation in a browser is not going to be a complete representation of reality. To think that is possible is really weird. So really, what is happening, we are arguing over the 'Title'?

Re: Show HN: Physically accurate black hole you can put in your room

#126

Post by aplavin »

20k wrote: post #61
csmoak wrote: post #15

Please correct me if I'm wrong, but it feels like the leading edge of the accretion disk (coming towards the viewer) should be significantly brighter than it is shown here, and the trailing edge (going away from) should be significantly dimmer? Or could the brightness shown be a result of it being Kerr vs Schwarzschild?

Yeah the doppler in this picture is all wrong unfortunately, the underlying equation used isn't right here (they mixed up spectral radiance and radiant flux). The rendering is also done without taking into account sRGB, and its run through a function that messes with the brightness - so the brightness is really incorrect. Plus all the colours are wrong (it uses an amhot colouring function, they aren't based on anythi…

Colormap/colorscale is generally considered an arbitrary choice in scientific plots or visualizations. Linear mapping of simulated emission brightness -> screen brightness could be a reasonable alternative mode, I agree – but it's weird to say that colormap choice makes it not accurate.

Re: Show HN: Physically accurate black hole you can put in your room

#128

Post by aplavin »

arianvanp wrote: post #77

The distortion effects dont work for me on pixel 8 when using AR mode I just get a flat floating image of a black hole. Am i holding it wrong?

Yes, as said in the text, unfortunately this is a limitation of browser APIs. You either get AR and no access to the camera feed (this is the AR mode here, black hole floating in your room, simply overlaid on top of the camera feed) or get access to the camera feeds but no AR (this is the camera mode). I didn't find a way around it...

Re: Show HN: Physically accurate black hole you can put in your room

#130

Post by fwip »

20k wrote: post #45
aplavin wrote: post #37

Earlier quoted context omitted.

Some are fair – of course this is a simplified visualization! Observationally, we don't really know how fast a given black hole is rotating, and here I indeed assumed a non-rotating one. It's not an inaccuracy per se, more like a missing feature. The camera mode has a (half-hidden) toggle to enable Kerr metric and set spin, but even there it's not a default. I consider the colormap choice to be completely arbitrary t…

>of course this is a simplified visualization Its titled a "physically accurate black hole"! Please don't do this, if its intentionally not physically accurate and heavily simplified! The general public on here don't know better, and it takes someone else with years of experience simulating black holes to dig through your code to show what you've simplified. There's like a few hundred people who have the right experi…

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