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All you need to do, is figure out a way to use electro magnetic radiation to slow down particles.
It's just a small technical challenge.
Technically that's already a thing. It is pretty expensive compared to a normal refrigerator though...
Easy, just invert the polarity of the microwaves
From these 2 sentences, I have written a 52 pages PowerPoint presentation to get funds from Wall Street.
I expect to find ~$2 bn.
See you in jail!
Hah! My ChatGPT bot did 60 slides in 90 seconds, and submitted it hours before yours. See YOU in court!
Hah! Jokes on both of you, I submitted a super generic patent for "cold microwave" YEARS ago to leech off of anyone who manages to actually invent this technology in my lifetime. See you BOTH in court (and probably also jail)!
Thereβs something called blast freezer, which is basically a freezer with fans inside, like what convection ovens have. It cools down food much faster than a standard freezer.
The problem is that cold is merely the absence of heat, you can't inject cold into something or generate cold, because there is no such thing as cold. It's kind of like how we can make a light bulb, but we can't make a dark bulb.
Maybe we could start manufacturing mini black holes to build the dark bulbs!
That's the best explanation I have seen for heat.
I've ran equations for heat so I get it more than most, but always found it difficult to explain.
Refrigerator
We have that, it's called a fridge, and then there's a freezer for making things frozen.
But a fridge is the opposite of an oven. Some kind of flash freezing would be like the unmicrowave.
The reason we shrink heating devices down but not cooling devices is a combined consequence of economics and the laws of thermodynamics.
First an analogy: Making a boat that moves downstream a river is easy. Take any buoyant material like a log or a branch and drop it in water. Presto, you've got a mode of transportation of any size. Want to go upstream? Now you need motors to fight the current. Putting a motor on a large piece of wood, (a boat) is economically viable. Putting one on thousands of sticks? Ain't nobody got time for that.
As a consequence of the laws of thermodynamics, the the universe naturally converts all potential energy (fuel, electricity) into heat. The universe will do this basically on its own, over time, constantly. This is called entropy.
Doing the reverse, taking heat and putting it back into potential energy, i.e. cooling, is difficult. You basically have to pay a price to the universe in some other way, kind of like how a motorboat has to push more water downstream than the current would have naturally moved on it's own. This is what heat pumps (AC, fridge) do. Heat pumps put some of that heat back into potential energy, in exchange for also releasing potential energy into heat... The trick here is to do these two things in different places. The fridge's motor converts some electrical energy into heat in exchange for being able to move some of the heat in the fridge outside of the fridge. The consequence of this is that the room the fridge is in is now hotter. Mostly because you took the heat in the fridge and moved it into the room, but also because the fridge's motor also added some MORE heat to the room in the process in order to fight entropy. So to actually make this useful, you need to insulate what you are cooling (or it will just get warm again, warmer than it was before, because you added heat to the room), and you also want to dispose of the heat in the room. So you pump that out into the atmosphere...
Anyway, long story short, you need insulation, refrigerant, motors, heat changers, lots of power to fight the universe's tendency to spread heat everywhere. Technically you could miniaturize these things, but they become less efficient as you shrink them down, to the point where things smaller than a fridge are just not practical to make compared to the benefit you get from having them.
Making small heating devices is easy. You don't need to fight the universe. You just need an apparatus that will "go with the flow".
a can of soda can cool faster in the freezer for ~30 min.
some people suggest adding an insulated sleeve.
i also use freezer to cool down coffee quickly.
< deleted. pls find info on fb/yt > ..
'projecting' energy is kinda easy... 'sucking' energy is difficult
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
Laser cooling exists, but I don't suppose you can afford one or want your beer on 2Β°K
How does that work?? Genuinely curious.
It's unintuitive, but super cool! There's a great video by Physics Girl and Veritasium that explain it better than I ever could here.
First, the wavelength of the laser (think of it as the "color" of the laser) is chosen such that the energy of the photons is just under the energy state of the atoms that you are trying to cool.
Now, when the atom is moving toward the source of the laser, this causes the atom to "see" a higher energy. This is called Doppler shift and is a very well-known effect in anything that emits waves and is moving. In fact, you've experienced it before when you hear a car horn -- as it moves towards you it has a higher pitch and as it moves away from you it has a lower pitch.
So, for atoms moving toward the source the see the energy rise just enough to absorb the photon and move to a higher energy state. Inevitably, the atom will want to move to a lower energy state (as all matter does) and will end up ejecting a new photon in a random direction. In order to maintain the conservation of momentum, this means that the photon will likely be ejected in a way that counteracts the direction it was previously moving, effectively slowing it down. Since heat is a measure of how fast atoms are moving, this means that atom has cooled down.
For atoms moving away from the laser source, they are unable to absorb the photons because the Doppler shift acts in the opposite direction, and they are completely unable to absorb the photons.
So as a result of all this, it is possible to slow down atoms moving in a very specific direction, without affecting the other atoms. This means you can systematically slow atoms down which means you can systematically cool things down.
Edit: Here's a piped link to the youtube video above in case you're privacy-conscious, however, Dianna (aka Physics Girl) has been bed-ridden with Long COVID for a while now so it would be great if you could contribute to her Patreon in lieu of the ad revenue