Comment by TGower
16 hours ago
It still amazes me that the rare shiny rocks humanity has appreciated for thousands of years also turn out to have amazing properties even compared to the synthetic materials we are now capable of creating. It's still the hardest material we have measured. It is the best thermal conductor, even though it's an electrical insulator.
> even compared to the synthetic materials we are now capable of creating
Aren't like almost all commercially used diamonds these days synthetic as well? As far as I can tell, other than just for the sake of them being "natural" or for having weird impurities that add color to them (read as: subjectively better to some people), no one wants/needs natural ones anymore.
Is “synthetic” the right word?
I thought they are “lab grown”.
(Synthetic implies non-real, when at a molecular level the lab grown are 100% real)
I think synthetic ~ synthesized in this context, as opposed to "not real".
Sense 4a1 here, not 4c: https://www.merriam-webster.com/dictionary/synthetic
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We can recreate lots of things, but almost always appreciate the true version better. It’s why it’s cooler to see the Mona Lisa than to see a poster print of it.
Why? As far as I can tell, other than just for the sake of the view being “natural” or having some weird color issues due to time and radiation and oxidization, nobody wants/needs the actual painting anymore.
Reason: because even when it’s identical or even inferior, the touch of nature is just… nice.
A painting has a 3 dimensional texture to the paint, while a poster is inevitably flat. Different paint compositions will also reflect light differently, while a poster won't.
So, yeah, having the real painting has additional value.
I wouldn't pay much for a painting anyway. I have several paintings and posters up on the walls, and they're interesting for a time, and then I just don't see them anymore. They're just part of the wall.
I think you just described the placebo effect!
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I've thought about this at times. How convenient that things seem to work out that way! Though I wonder if it's more just a bias. All the very impressive things you can make from the abundant materials have already been made. Like, say, all of life?
Blue pigments used to be extremely rare and precious. Then some chemists found the infinite blue glitch.
Also the convert energy into aluminum glitch.
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Diamonds are crystals, like silicon Nothing wrong with liking shiny rocks, but they aren't that rare and we can generally produce them. Materials have properties. Understanding the properties generally gives us leverage to use them in our own benefit.
It is a very good thermal conductor, but not the best. At low temperatures, copper is better. At very low temperatures, helium is much better.
Superfluid helium's maximum thermal conductivity is roughly 100x diamond's maximum!
Neat! At around the temperature of liquid water, it's still about five times as good as copper.
So.
1. They can grow diamonds.
2. Diamonds are good for heat conduction in the liquid-water-temperature range.
3. Diamonds are good for electrical insulation.
Where are the full diamond water blocks for the water cooled RGB bling computers?!?
They make nice (and expensive) tweeters, too.
https://www.madisoundspeakerstore.com/diamond-dome-tweeters/...
>Superfluid helium's maximum thermal conductivity is roughly 100x diamond's maximum!
Never thought about this before. Would that mean that heat propagates much more quickly? Possibly even approaching the speed of sound of the material?
Thermal conductivity measures the heat flux given a temperature gradient. That is, how fast heat energy flows across a surface, given a certain temperature gradient across it.
It has nothing to do with the velocity of the heat carriers themselves (phonons, or charged particles).
E.g. phonons always travel at the speed of sound, in any material.
Slide 12. Pretty much yeah. https://indico.cern.ch/event/1541024/attachments/3055157/540...
You can kind of isolate the different vibrational modes and their corresponding energy transmission. "Phonons" are basically sound waves (the particle analogue), labeled in figure 2: https://www.nist.gov/system/files/documents/2019/07/12/dcs_2...