Originally published at: https://boingboing.net/2019/10/08/this-scientific-paper-about-bl.html
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Might have been an even more effective illustration if painted in vantablack.
However, well done regardless!
So when people talk about the “size” of a black hole, they usually mean the circumference of the event horizon. Is there anything that could be considered a “surface”? After all if an object crosses the even horizon, it just keeps falling, right? And with the curvature of space, is the radius infinite?
Black hole or redacted picture of a black hole?
Maybe:
How black holes really work is still very much an open subject testing the limits of relativity and quantum mechanics and how they contradict each other. My suggestion is that you stay a safe distance from any event horison you happen to encounter.
Black holes are self-redacting.
Though as with the nature of black hole mechanics inside the event horizon @Bernel points out, the actual mechanics of the event horizon are poorly understood.
“C’est ne pas un PBH”…
Holy TLAs, Batman!
PBH = primordial black holes
TNO = Trans-Neptunian Objects
OGLE = Optical Gravitational Lensing Experiment
Not sure this helps…
<exercise left for the reader>
(it’s distributed as a PDF, so whoever prints it out can coat it in Vb)
That nomenclature “5 M ☉” indicates that this five-inch diameter ball has the mass of five Suns. It’s a bit difficult for us humans to comprehend the compression ratio that this implies.
And DM halo = ‘dark matter halo’, for what its’ worth.
That’s actually “5 M🜨”, or five Earth masses.
Lurks is correct, that subscript is ⨁, where M⨁ denotes the mass of Earth. But the subscript Nixie wrote is M☉, which is used to denote the mass of Earth’s sun in astronomy. On a small screen, they’re difficult to distinguish. For those who can’t see it, Earth is a little cross-hairs and the Sun is a dot within a circle.
Starting to wonder if the reliance on 24th century iPads explains a lot of Starfleet mishaps.
On a small screen, they’re difficult to distinguish
Couple that with an overly aggressive compression algorithm and an overly optimistic anti-aliasing algorithm.
The original pdf has readily discernible glyphs.
I just thought I’d point it out since IIRC @nixiebunny’s day job is related to radio astronomy, so I’d be surprised if he didn’t know the notation, but I tried looking at it on my large-ish screen phone and couldn’t make it out despite excellent vision for my age. On the big LCD in my office it’s obvious.
It’s hard to see those little symbols clearly in the PDF file preview window in my browser. I usually read papers with a proper standalone PDF viewer program. I don’t know why they use such tiny symbols to indicate such big numbers!
Besides, I’m in the engineering end of things, so I don’t go reading a lot of papers with masses of various bodies.
I’m looking at this on my desktop monitor, and it’s clear there. But I can easily believe it’s hard, or even impossible, to tell the difference if you’re looking at it on a smartphone screen.