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Probably a stupid question, but will we ever have something like a microwave to make things cold? Is there a reason this can't exist?
(lemmy.dbzer0.com)
this post was submitted on 14 Sep 2023
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if you see a dark area you can turn on a flashlight to emit light towards the area and make it not-dark.
If you see a lit area and you want it unlit, there is no anti-flashlight you can point towards it to suck the light out.
Similar kind of thing, heat can only be given, not taken. heating stuff up is easy, but for cooling the best you can do in most cases is to make it easier for the thing to give you its heat (ex by the atmosphere colder), but you can't force it.
This is fundamentally not true.
Light is made of electromagnetic waves. If you can control the timing of those waves precisely enough, you can add another light with the opposite phase (an inverted wave) that will cancel out the other light.
This is what happens in the famous "double slit experiment". It's also the same principal as noise cancelling headphones albeit with sound pressure waves instead of EM waves.
Scientists have actually cooled atoms very close to absolute zero by shining a laser at them
I said "in most cases". I am aware that it is possible. We're looking at a macroscopic system here though. A microwave, not a couple of atoms in a lab. good luck cooling a couple of atoms in the center of an opaque blob of food with a laser
I completely agree with your third point where you said "in most cases".
It was your first two points trying to create an analogy with light that I was responding to
I mean like the analogy holds until quantum mechanics - which is pretty good - no need to nitpick
Neither EM wave interference nor noise cancelling headphones are quantum mechanics. It's not nitpicking.
quantification of light as a particle and the theory of its wave particle duality yes is by definition quantum mechanics, which was proven first by the double slit expierament. Up until then 2 light sources never canceled each other out so it was assumed light is 100% quantifiable and a particle.
(quantify is actually where the word quantum comes from)
noise canceling headphones you're good for tho, the existence of waves is a different subject
Edit: and IG if we want to talk about fundamentally untrue then, your comments also wrong cause its a pretty big thing in science that light ISNT just a wave... but of course I'm not being nitpicky right?
It was theorized that light could be a wave way before the double slit experiment. Like, a century before. So no, it wasn't "assumed light is 100%" quantized before that experiment.
Anything that is a wave can be cancelled, so this idea was baked right into the wave theory of light, they just didn't have the ability to control light precisely enough to prove it until the double slit experiment. You don't need quantum mechanics to explain wave theory, it just happened that the double slit experiment, while proving that light behaved like a wave, also showed other characteristics that it was also behaving in a quantized fashion. The fact that light is quantized into photons has nothing to do with the fact that they cancel so you really don't need quantum mechanics to explain it. The reason light can be cancelled is exactly the same as every other thing in physics that behaves like a wave.
The word quantum comes from the word quantization not "quantify". Those two words mean different things
Light is a wave. It also happens to be a particle. So the "existence of waves" is not a different subject. It's exactly this subject
Edit: Love the snarky edit to a post full of being confidently wrong. I'm going to go engage with others. Good day, sir/ma'am!
Quantify and quantization youre saying have different root words? their similarity in definition and to the Latin word quantus is just coincidence? (whoops nitpicky ahem ahem)
And of course it was hypothesized but never proven, double slit pushed it towards theory/fact
but also I'm not sure if you know where the line of quantum mechanics to newtonian mechanics are, cause newton definitely didn't theorize too much about the energy of light