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A comment on To make the perfect mirror, physicists confront the mystery of glass.

Re:To make the perfect mirror, physicists confront the myste... by metaphor on Friday April 03, 2020 @06:52AM (#22767930)
> ...Ediger and his team dropped molecules one by one onto a surface as if they were Tetris pieces, allowing them to find snug fits.

Let's assume a 40kg super mirror was made from the same base silica[1]/tantala[2] substrate as the legacy mirror. Let's also assume 50% distribution by mass.

That's a (20kg/60.08g/mol)+(20kg/441.893g/mol) ~= 378.1mol tetris endgame.

So if we took this analogy quite literally and wanted to build 1 mirror in 10 years, you'd have to play precision atomic tetris a mere 17 orders of magnitude faster than this guy[3].

Not going to lie...sure does make watching grass grow sound a lot more pragmatic.

[1] https://en.wikipedia.org/wiki/Silicon_dioxide

[2] https://en.wikipedia.org/wiki/Tantalum_pentoxide

[3] https://www.youtube.com/watch?v=v3TJXSFnVS4

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Re:To make the perfect mirror, physicists confront the myste... by mrob on Friday April 03, 2020 @08:56AM (#22768699)
Most of the mass is in the supporting base layer, which presumably does not contribute much noise. If this layer also needs to be special glass then why are the LIGO scientists even considering using it? I assume they are not idiots, and only the wavelength-thick layers need to be assembled molecule by molecule.
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Re:To make the perfect mirror, physicists confront the myste... by lachlan-sneff on Friday April 03, 2020 @11:25AM (#22770170)
Totally possible through convergent assembly.
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Re:To make the perfect mirror, physicists confront the myste... by metaphor on Friday April 03, 2020 @08:34PM (#22775203)
Ahh, so that's the scalable magic trick they're playing. Thanks for the insight!
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Re:To make the perfect mirror, physicists confront the myste... by ipnon on Friday April 03, 2020 @10:56AM (#22769798)
Quanta Magazine is not great reading for the practical and expeditious.
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Re:To make the perfect mirror, physicists confront the myste... by JadeNB on Friday April 03, 2020 @01:05PM (#22771522)
Why not? I've found Quanta Magazine great reading for pretty much everyone. All I can judge as an expert is their articles on mathematics, and they're not technical reports, but a howler in a Quanta math article is rare, whereas in any other popular article I would expect to find at least one major error per statement.
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Re:To make the perfect mirror, physicists confront the myste... by craftinator on Saturday April 04, 2020 @02:52AM (#22776688)
Quite sensationalistic. They go out of their way to obfuscate titles.
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