Yes, when it makes the front page of the FT (2 days ago) you know there's some interesting stuff going on. The whole article is worth a read (I didn't known JD Vance's career was "largely bankrolled by Thiel").
>US tech billionaire and Maga donor Peter Thiel is starting a series of closed-door lectures about the antichrist in Rome on Sunday, putting him on a collision course with Pope Leo XIV, the Catholic Church’s first American pontiff....
As a strong supporter of Ukraine, I would say ultimately wars are won or lost by economic forces (the side that can't afford it any more loses). That's how the USSR lost the Cold War, and all I can hope is that all of Europe really has your back in this one.
World War 2 was not won due to the economy. And while it is true that the USSR "lost" the Cold War, they actually spent too much and entered a recurring debt from which they could no longer get out. There was no direct war here, which is different to e. g. world war 2 (at the least USA versus Germany). USSR and USA only fought some proxy wars.
World War 2 was won due to the economy. Only the Allied side had the economic strength to replace all of their material war losses and more. In some categories of munitions the USA out produced Japan by a factor of >1000. US Navy gunners could afford to fill the sky with steel because they had unlimited supplies. The enemy had to count every shot.
It was literally won due to the economy. The moment Germans failed to knock out Soviets and Japanese pulled Americans into the fight their days were numbered due to insane industrial base of the both countries. Soviet meat waves, industry + lend lease won Europe and US finished Japanese.
I agree it's an unfortunate way of presenting it but Stalin was a guy who didn't care for anyone's life and was literally sending people in waves to die with the NKVD sadists shooting scared young boys whenever they tried to run away from the horror of war. Dead if you go, dead if you don't. It's romanticized an celebrated today, but it was a mass tragedy incomparable to one that happened to ny other country in recent history.
Didn't their war in Afghanistan precipitate their downfall?
So many pivotal decisions in WW2 were economic in nature. Lend lease? Germany's late switch to a war economy? The Allies' much larger manufacturing capabilities?
You could also argue that the cold war stayed cold because of the West's economic might. It set a military and living standard that the USSR bankrupted itself trying to match.
Russia will win on this one. Productions are largely internal. What they lack they get from China. Ukraine loss so many men. Their populations will just go down from now on. USA and China are on the verge of recessions. I really doubt USA will prioritize Ukraine over Israel or China ignoring its own needs. Cede the land and rebuilt. Better to cut losses now than even more loss.
Something based on the principles of 'New'? (not clear on the details of how Show HN works, does it automatically appear?). Just shove entries under 'New' and let the group decide what is "Show HN"-worthy.
The light is produced by electrons combining with holes, so the size of the material doesn't come into it (unlike an antenna). I've personally pushed* a single rubidium atom about in a quantum computer and watched it move by emitted light (rubidium atom: ~0.25nm, emitted light 420nm depending on excitation).
* Ok, actually pressed buttons that manipulated the electric field that was trapping the atom and watched the result on a display - lot of physics going on behind the scenes.
Something akin to reciprocity still applies, no? You have a tiny rubidium atom, way too small to couple particularly strongly to the electromagnetic field at visible wavelengths. So it has a low cross-section for absorbing visible light. Won’t it necessarily radiate rather slowly as a result?
I would expect this to be somewhat of a problem with tiny LEDs. In an LED, you inject electrons and holes and you hope that a magical quantum process happens in which an electron and a hole meet, annihilate each other, and emit a photon. But this process is slow, and the electrons and the holes may wander around for a bit before combining. But in a very very small LED, smaller than the mean free path, I’d imagine you might have an issue where the electrons and holes frequently make it all the way across the device without recombining and manage to lose their energy as heat when they hit the opposite electrode. (I have not drawn the diagrams or checked the math here.)
(I took the relevant classes in grad school, but I’ve never done this sort of work academically or professionally, so no promises that I’m right.)
"Something akin to reciprocity still applies, no?"
Not necessarily. Chiral gold nanocrystals can be as small as 10nm and still be excited by 808nm laser light causing two-photon absorption and emitting in the visible range.
There is some kind of reciprocity, e.g. when an atom absorbs light and it passes into a higher energy level, it will spontaneously emit light going back to the initial energy level, with about the same probability with which it has absorbed the light.
However this reciprocity is frequently circumvented, because atoms and ions have a lot of energy levels. Instead of re-emitting the light, the atom may pass more quickly to another energy level, and from there it may emit light with a very different probability (and of a different frequency, i.e. this is fluorescence).
While in fluorescence light with a lower frequency is emitted, there is also the opposite case. In very intense light, e.g. from lasers, multi-photon absorption may happen. In that case there is also no reciprocity, because the atom has jumped an energy difference higher than that of the incoming photons. So it may re-emit light with a higher frequency.
With rubidium atoms, multi-photon absorption is very frequently used, for Doppler-effect-free spectroscopy (by absorbing photons that come from opposite directions, so that the effects of the movement of the atom will cancel). In comparison with other atoms, rubidium vapor cells are easy to procure, for spectroscopy experiments, or for use in frequency or wavelength standards, but they still are rather expensive, especially when enriched in only one of the two rubidium isotopes (e.g. if you want just rubidium 87, instead of natural rubidium, a Rb vapor cell may cost close to $1200).
Depends on the definition of slowly - thousands of photons per second upwards (and detectors are so sensitive these days that makes seeing easy). Lots of articles about on the subject, given the potential uses of this system.
It's probably more impressive that the LED was manufactured with light photons. I know it's "normal lithography" problems, but making a 500nm device out of 300nm or 400nm waves of light is downright impressive.
In the UK we have in fact discovered an alarming weakness in the concrete used to build schools, hospitals and other public building (in one case, the roof of a primary school collapsed without warning). The response was basically "Everybody out now".
It's pretty easy to do, a Pi (of any kind) and an IR LED that sends the power button codes for the common TV brands will do it (since it's often a toggle, it'll also turn TV's on if they are off).
RF remotes are harder to hack together but similar principle. Whether IR or RF, the codes are common across all devices of the same model/protocol.
>US tech billionaire and Maga donor Peter Thiel is starting a series of closed-door lectures about the antichrist in Rome on Sunday, putting him on a collision course with Pope Leo XIV, the Catholic Church’s first American pontiff....
* https://www.ft.com/content/fc1e7e9a-9d5d-4217-b9b2-38069eb11...
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