Your numbers seem reasonable — more intuitive for me to work in terms of pressure. Atmosphere is (roughly) 1e3 Torr, good UHV can be around 1e-10, so that’s 13 orders of magnitude, which is (roughly) the same difference that you calculated.
Aluminum foil is very common in physics labs. And a main use for it is “baking”! To get ultra high vacuum (UHV)* you generally need to “bake out” your chamber while you pump down. Foil is used same as with baking food — keep the heat in and evenly distributed on the chamber.
Sadly, it’s usually not food grade aluminum foil, as that can contain oils, and oils and vacuum are generally a big no-no.
*Just how good is UHV? Roughly: I live in San Francisco, which is ~7 miles by ~7 miles (~11km). Imagine you raise that by another 7 miles to make a cube. Now, evacuate every last molecule of gas out of it. Now take a family sedan’s trunk, fill it with 1 atmosphere of gas, and release that into the 7 mile cube. That’s roughly UHV pressure.
From TFA:
“I have failed you completely and catastrophically,” Gemini CLI output stated. “My review of the commands confirms my gross incompetence.”
https://en.m.wikipedia.org/wiki/Blackbird_(wind-powered_vehicle)
Can go directly upwind (no tacking required). Can also be applied to boats.
Sorry you’re getting down voted — lots of replies from folks unclear on what the diffraction limit means, atomic resonances, etc.: https://www.newscientist.com/article/2161094-a-single-atom-is-visible-to-the-naked-eye-in-this-stunning-photo/
Parent didn’t say resolve, they said see — you can’t resolve stars but you can most certainly see them.
Light up a single atom enough and you can see it (unclear if this works with a dark adjusted naked eye or if a long exposure is required): https://www.newscientist.com/article/2161094-a-single-atom-is-visible-to-the-naked-eye-in-this-stunning-photo/
No, they’re too small to resolve. You can see small things if they’re bright enough: https://www.newscientist.com/article/2161094-a-single-atom-is-visible-to-the-naked-eye-in-this-stunning-photo/
A single atom of gold is far too small for any photon in the visible spectrum to interact with.
That’s incorrect — single atoms can, and do, interact with optical photons.
https://arxiv.org/abs/2410.19671 https://www.nature.com/articles/ncomms13716
And the entire field of super resolution microscopy relies on small things (e.g., molecules) interacting with light.
The energy from nuclear reactions can be astonishingly large (compared to, say, chemical reactions).
But atoms are really, really, really small.
My recollection is that the DVD included that library, but it’s been a while…
Most Linux filesystems, being case sensitive, won’t find the SUDO command.
No, I’ve been a strict vegetarian for a long time, mostly vegan now but not strict about it. I did eat fish a few years ago because it was an invasive species (and also, delicious).
But also, I have no problem getting the food/nutrients I need from a plant based diet, which isn’t always easy for other folks.
Thanks for the thoughtful response! 1) makes a lot of sense, and 2) makes a lot of “emotional sense” to me (as opposed to “intellectual sense,” I guess).
What’s the conventional wisdom as to why this is so bad, but eating meat basically gets a pass? Like, meat offers sustenance, yes, but it’s by no means required. So basically, humans eat meat because it tastes really good — it’s great “culinary entertainment.”
This is a different kind of entertainment, but it’s deeply offensive to many folks. I’m not trying to be a dick about it, just curious why this is seen as such a sin.
Is it that these animals weren’t “supposed” to be killed? Would a movie about a beef cow who ends up getting slaughtered, both onscreen and IRL, be seen as better? Worse?
That’s basically the best possible outcome.
Toddlers are the reason why, despite being able to afford nice furniture for the first time in our life, we’re sticking with ratty couches and old Ikea coffee tables.
…are Turing Complete, so what you can do with them is exactly equal.
But they’re only equal in the Turing complete sense, which (iirc) says nothing about performance or timing.
Yep, you’re right — I was just responding to parent’s comment about fiber being best because nothing is faster than light :)
That’s…not really a cogent argument.
Satellites connect to ground using radio/microwave (or even laser), all of which are electromagnetic radiation and travel at the speed of light (in vacuum).
Light in a fiber travels much more slowly than in vacuum — light in fiber travels at around 67% the speed of light in vacuum (depends on the fiber). In contrast, signals through cat7 twisted pair (Ethernet) can be north of 75%, and coaxial cable can be north of 80% (even higher for air dielectric). Note that these are all carrying electromagnetic waves, they’re just a) not in free space and b) generally not optical frequency, so we don’t call them light, but they are still governed by the same equations and limitations.
If you want to get signals from point A to point B fastest (lowest latency), you don’t use fiber, you probably use microwaves: https://arstechnica.com/information-technology/2016/11/private-microwave-networks-financial-hft/
Finally, the reason fiber is so good is complicated, but has to do with the fact that “physics bandwidth” tends to care about fractional bandwidth (“delta frequency divided by frequency”), whereas “information bandwidth” cares about absolute bandwidth (“delta frequency”), all else being equal (looking at you, SNR). Fiber uses optical frequencies, which can be hundreds of THz — so a tiny fractional bandwidth is a huge absolute bandwidth.
Our Internet went out for a few hours today, so naturally my smart switches, lights, cameras, motion sensors, door sensors, and power monitoring… continued to work as of nothing was wrong.
Home Assistant is great, and using local-only devices is awesome. If my smart home stops working it’s my own fault, not some 3rd party.