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?

Melatonin@lemmy.dbzer0.com to Asklemmy@lemmy.ml – 486 points –
241

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.

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)!

Calm down there Elizabeth Holmes

Easy, just invert the polarity of the microwaves

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Thereโ€™s 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.

It's on my list when I have fuck you money. Next to a pacojet

The pacojet is way expensive, also, the pacojet patents runned off and now there exists way cheaper alternatives that work in the same way. Check out the NinjaCream.

I did but I really want the pacojet :)

Why? Not challenging, just wondering what the pacojet does that other machines can't

Just reading a quick review of the Ninja Creamy, the Pacojet can run without putting chunks of plastic in your ice cream.

"In early 2023, a moderator in the Ninja Creami Community Facebook group introduced a new rule: No more posts about the plastic issue, lest they clog up the group."

Yeah that seems bad lol. I feel like there has to be an option in between $200(creami) and $7000(pacojet) that can avoid chunks of plastic though

I just looked at the website for the pacojet since Iโ€™d never heard of it: legit the most patronising website Iโ€™ve ever seen in my life

Check out the Ninja Creamie for something almost exactly like the Pacojet but much more affordable.

Well, yes, but then I wouldn't need fuckyou money

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!

Nope that's unfortunately not how black holes work. It would essentially look the same as having the bulb painted black.

Practically speaking I think having a mini black hole in your home would look like being rapidly crushed to death.

I bet if you had a black hole with a wall on one side and a light on the other, it'd cast a really trippy shadow.

Sadly, a mini black hole would suck up everything around it. Much like a tiny Katamari Damacy, it would quite quickly consume everyone and everything around it. Of course after not too long it would become a regular sized black hole.

Some mini black holes do not grow into black holes. They collapse. The issue is that they aren't stable for any decent length of time. Fractions of a nanosecond.

A capitalist haven, think of how many black holes one could sell!

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.

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".

There are blast chillers that are closer to a microwave

Depending on where you live and the season, that could be called stepping outside.

They meant quickly. A fridge nor a freezer can make things cold or frozen in a minute or two.

Those devices are very slow at transferring heat, unlike the microwave.

Temperature is average kinetic energy. It is very easy to put kinetic energy into an object and much harder to take it out. Microwaves do it by shining a โ€œlightโ€ tuned to microwave frequencies on objects. So you can imagine the problem is about as hard as shining a lamp on something and having it get colder. Laser-based cooling methods do exist but theyโ€™re quite expensive and mostly operate on the atomic scale. For now, the best way we know of to cool large items in bulk is to put them next to something thatโ€™s even colderโ€”in short, a refrigerator.

Fridge?

There are devices that will cool a drink (can of soda or a beer) to 'ice cold' ( I assume something like 5ยฐ) in 60 seconds. I guess this sort of answers your question? The full answer is probably not that it is technically impossible, but that the practical use is largely limited to drinks.

You can dump energy into something by blasting photons at it, because photons carry energy. You can't do the reverse because you'd need to use particles with negative energy. Either that, or you'd need to suck photons out of the food, but it doesn't work that way; things radiate photons at a specific frequency and intensity (called blackbody radiation) depending on how hot they are, and you can't make them emit more energy except by getting them hotter.

Allow me to introduce you to this

https://en.m.wikipedia.org/wiki/Laser_cooling

Can I get an ELI5 of this principle? I read the Doppler cooling part but I can't connect the dots.

Heat energy is the amount of particle wiggling. With precisely tuned and oriented lasers you can clamp a particle in space, thus prevent it from wiggling.

No wiggling -> very cold.

It's like slowing cars by crashing another car into them. But it's photons instead from the exact opposite direction.

A common misconception. Take the so called "light bulb" for instance. People think they emit light. They do not. They ingest darkness. They are dark suckers. They pull in all the darkness around them, but objects get in the way, and that's why there are shadows. And when they're full, they stop working. That's why they have a brown spot when they stop working, they are full of dark.

Don't fall for the light emitting conspiracy. LONG LIVE THE DARK SUCKERS!!!

For a second I didn't think this was a meme, and I was like "I'm pretty sure that's not how it works."

It was a risk not adding /s especially since I tried really hard to not be too absurd as to be obvious. I will take your unease as a compliment :)

Considering room pressure and temperature, things are not cooling at their fastest possible rate. Blackbody radiation isn't the only way things cool down. You are forgetting conduction and convection. Liquid nitrogen can cool things down super quickly.

I'm not forgetting them: they're just but relevant to the way I interpreted the question. I'm assuming OP wants something that works on a similar physical principle to a microwave, not just a fast way to chill things.

Ah sure, yeah, if they want it to actually use radiation, it's not possible.

Refrigeration Tech here. See: Traulson Blast Chiller. I imagine there'd be a consumer version if enough people wanted them.

But isn't the cooling method an airflow and steady temperature decrease of the chamber?

Seems more like a reverse convection oven than a microwave.

But thanks otherwise. I never knew these existed. Was an interesting read.

Without breaking the laws of thermodynamics, I'm not sure how you'd accomplish that. Being you can't "make" something cold. You can only remove the heat...

Blast Chillers can make 160ยฐF Poultry 34ยฐF quite fast. Mind you that's internal Temps. As far as I know, airflow is the best, maybe only way to carry the heat away...

I got that. It was more about how the Blast Chiller generally functions. It does not use radiation from the electromagnetic spectrum like a microwave, but uses airflow like the afromentioned convection oven. But thanks again for explaining. I appreciate the additional input.

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?

  1. 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.

  2. 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.

  3. The word quantum comes from the word quantization not "quantify". Those two words mean different things

  4. 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

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Laser cooling exists, but I don't suppose you can afford one or want your beer on 2ยฐK

it also helps to be cooling a single atom at a time

A lot of laser coolers were built exactly for cooling single atoms (to do scientific research)

How does that work?? Genuinely curious.

Basicly photons are shot against an atom to slow it down (the slower the elements move the "colder" something gets)

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

Thank you!! This was a fantastic explanation! Great ELI5 style, I feel I don't even need to watch that video - even though Veritasium is amazing.

This is a bit like asking if we could build a flashlight that emits a beam of darkness I think

It's not. A device that rapidly cools things down placed inside it isn't implausible. He's not asking for a beam of absence, he's asking for an enclosed space that subtracts heat.

Shooting something with โ€œcold energy beamsโ€ is an anti-microwave

We arenโ€™t talking about machines to make things cold, I was asked if we could make microwaves that make stuff cold

Very much so, and equally possible in theory (interference patterns with light exist, light cancellation could work somewhat like noise cancelling) but also equally impossible to do at anything much above an atomic scale.

There are actually two ways to do this. One is a heat pump (like a small ac or an electric cooling plate) the issue is that it would heat up on the other side, so not great.

The other option is actually really interesting as just like a microwave it uses radio waves (in this case lasers) to cool things by shooting the atoms in a way that negates their current movment and slows them down.

Oh, so that's why when I shot someone they got cold! Silly me. I'm a reverse microwave, not a murderer duh

Came here to mention laser cooling; glad someone else got there first.

In reductively simple terms heat is really easy to generate. In fact pretty much everything we do creates extra heat entirely on accident, so a device than make things hot on purpose is actually surprisingly simple. It's much harder to get rid of. The only economical way we've found of managing it is by using to phase change of refrigerants to pump it out of enclosed spaces, which is how refrigerators and air conditioners currently work. Everything else would be more complex, less efficient, or both. So if such a thing is even possible it would almost certainly be much more expensive

It's called a freezer and it just takes a bit longer.

The simple answer is entropy. It's much easier to poor a bunch of energy into something and have it express itself as heat than it is to retrieve spent energy out of an object. You can burn down a forest and make a lot of light and heat, but you can't spend light and heat to turn smoke into a dark, cold forest.

We cant do it now thats true. But isnt the process you described called photosynthesis? Using Sunlight (heat in form of UV Waves) to turn Smoke (CO2 and bunch of other stuff that isnt used) with Water into sugars which build the structure of plants?

There is a machine that specifically cools drinks (cans) in seconds. It rolls the can in ice water until it's cold.

why the roll?

Probably to disrupt the temperature gradient that forms around the can. Thatโ€™s why we blow air on though the top of a hot drink to cool it faster.

I assume so the liquid moves around and gets cooled evenly. If you didn't move the drink, the outer layer of liquid would get cold, but the inside would take longer to get cold as well

Heat transfer by convection

Technically not by convection because that is the movement of fluid to transfer heat in and out of something, like air conditioning. The bath is not a moving fluid it is a simple constant temperature. The spinning moves the fluid inside the can so more of it touches the aluminum wall, which is being cooled by conduction with the ice bath.

There's a lot of posts here not answering the question or saying it's impossible.

A reverse microwave is possible.

The 1997 Nobel Prize in physics was awarded for the development of methods to cool and trap atoms with laser light.

It's just very hard to do and no one has successfully cooled a large complex object with laser-based cooling.

This is technically possible. The cosmic microwave background, i.e. space, is extremely cold (barely above absolute zero) so it basically acts as a heatsink you can pump infinite amounts of heat into. It turns out that if you can make the food radiate heat out into space and prevent it from absorbing more heat from sunlight, it's possible to cool it below ambient temperature. This is also a completely passive process so it requires no electricity or other form of active energy input.

The problem with this is that doing it with food might be impossible. At the moment, we can only really do it using objects with special coatings that have been optimized for this purpose.

Here's a couple interesting videos that explain how it works:

https://www.youtube.com/watch?v=KDRnEm-B3AI

https://www.youtube.com/watch?v=dNs_kNilSjk

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Push heat into something is easier than pull heat out of something

Cool question. Iโ€˜d imagine the easiest way I can at least think of is spraying it with liquid nitrogen. The challenge will be to get the nitrogen back in the bottle and keep it liquid in the meantime.

I think that'd shake out to being an air conditioner with nitrogen as the "air." You'd lose some nitrogen every use, but nitrogen is cheap.

The problem is your piece of pizza would become as brittle and sharp as ice, and likely to injure you if you handled it.

Who wants to cool pizza? If imagine this would mostly be used on drinks, or frozen treats like the ice cream in their picture.

Terrible use for ice cream too, actually. Flash freezing it and not whipping it at the same time totally ruins ice cream.

Ah brick of frozen milk... large ice crystals to crunch on and a surface like concrete. My favorite kind of ice cream

Properly flash-frozen ice cream is actually very smooth since the ice crystals are very small. The water freezes before it has a chance to form large crystals.

Neat. I mean makes sense considering dip n dots

Haha probably, but it was the only thing I could think of that people would want to be cold faster. Maybe some other desserts, like lemon meringue or banana cream pies.

Iโ€˜m baffled our usernames only differ by one letter. My idea was, if you โ€žsprayedโ€œ the item from afar, it would cool the surrounding air and only ever so slightly touch that item. I donโ€™t think this would flash freeze it. Feel free to correct me.

There's commercial equipment called blast chillers but it still takes like 10-15 minutes

Part of the problem is if you want to chill something, like a warm beer or bottle of wine, you dont want to freeze any part of it. Sure you could dubk it in superchilled liquid nitrogen at -255 or whatever, but the heat energy leaves the object from the outside, and the liquid nearer the edge would freeze before you got the middle cold. You might also thermally shock the glass and break it.

The fastest way to chill a wine or beer would probably to put it in an immersion bath fully submerged in a dense, thermally conductive liquid like salt water, kept at a temperature of -2 degrees C or so, and a pump to circulate it around, like a cold sous-vide where maximum surfacearea is being exposed to the chilling liquid. If you left it in long enought it might eventually freeze, but you could optimise immersion time and bottle temperature to ensure that its inner heat energy and thermal transfer rate is enough to prevent the liquid at the outer edge from freezig.

If your wine or beer had a magnetic stir bar or something inside to keep the temperature of the inner liquid circulating and thermally consistent, your saltwater bath could go even colder, but that would introduce other problems like nucleating the carbon dioxide in the beer or wine.

It is called liquid nitrogen and it is too expensive to store.

It's not just too expensive to store, it's thermodynamically impossible to store indefinitely at room temperature.

Lemmy sure has gotten popular, bunch of comments that doesn't understand how microwaves work

Commercial kitchens sometimes have blast chillers and blast freezers. Some of the cooking shows use them.

Well, it does exist, it's called laser cooling, but it's only if you want to have things really cold

It's a lot easier to generate heat from electricity than to transfer them out. Closest bet would be just blasting cold air but heat transfer will be slow so it's still quite limited.

Probably not. Nice choice of pic to illustrate the need, though ๐Ÿ˜„

There is! It's called a blast chiller and just takes a dumby amount of energy proportional the amount of energy removed from the food. It's easier to add than subtract.

You would need to find a way to make food spontaneously emit microwaves so it loses energy and cools off. That probably involves altering the strength of one of the nuclear forces or something.

You should try to build a chamber that sprays liquid nitrogen or other cryogenic liquids at the food.

Idk, good luck.

I believe that the problem with this method is that the nitrogen will expand in contact with the hot object, and this being a chamber means that there's risk of explosion.

They never said the chamber had to be pressure tight ...

There is a drink chiller that chills drinks in about a minute. You could use the same idea for other things.

The Chill-O-Matic is smaller, cheaper and probably easier to clean as it doesn't seem to have tubing.

The design of that machine in your link is a lot of overkill for something simple.

In beer brewing there's a point where you want to cool your beer down as quickly as possible.
A chiller is dropped into the just cooked wort. (wort is the beer before fermentation).
It goes from steaming hot to room temperature very quickly.
It's just a spiral pipe that you run cold water through.
Sounds like you need something like that for a potato.

These are all word for word the same answers to the not poop for 3 days quest.

That's an air conditioner. Or a fridge.

You just need to adjust the output and input sizes. Do to like... physics. It is easier to add heat to a system than to remove it.

It occurs to me that you could get some really high-speed cooling with liquid nitrogen (or dry ice and alcohol) but the reality of working with cryogenic fluids is that they're pretty dangerous so I don't think anyone would do that. Unlike a microwave where the dangerous part (the waves) is all self-contained and turns off the instant you open the door.

Fridge, well. But now I'm wondering if that would be possible with electromagnetic radiation somehow. Would it be possible to direct infrared waves away from a closed chamber, making the inside cooler? Like a semipermeable membrane in shoes with water vapor?

Removing heat energy is what your freezer does, by transferring it outside of the freezer box.

You canโ€™t just remove heat by adding electromagnetic energy. Absorbing energy from the electromagnetic radiation makes heat.

Edit: whelp, TIL

You canโ€™t just remove heat by adding electromagnetic energy.

Except that you can.

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The magnetocaloric effect can do this. Instead of the target absorbing energy, the magnet does. The magnet heats up and the target cools.

If you're very careful you can remove heat with electromagnetic energy.

Think of heat like someone on a rope swing, and electromagnetic energy as a push.

If you time, and angle your pushes very carefully you can slow the person on the swing. But it's much easier to speed them up. Same with electromagnetic energy.

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Yeah there are those machines that like instantly cool your soda can or make ice cream instantly supposedly. They just bathe it in ice and salt water for some time basically

Cold doesn't exist, it is merely the absence of heat. Easier to insert heat than remove it, same reason why you can put on warmer clothes in the winter, but you can't make yourself cold in the summer.

I donโ€™t know if itโ€™s a stupid question or not but I have been wondering this myself for years. :)

yeah, not only microwave but heater in general... but reversed, i asked myself that question for a long time, i mean we pump an electricity into the wire and we get heat, why not reverse? why we can "magically" get heat from electrons but to get something cold we need to pump the heat elsewhere, like microwave basically make atoms vibrate generating heat, would be cool to be able to generate some field that makes atoms stop

You cannot just destroy energy. When you "make atoms stop" the energy from atoms have to go somewhere.

Usually atoms radiate heat away.

Heat is energy release, your start with stored energy and release it. To make something cold you either have to capture energy (hard) or move it away (heat pump / refrigeration)

Laser setups that can cool individual atoms exists but they're not trivial whatsoever and they cool them by canceling atomic movement by hitting them with lasers opposing their current momentum to slow them down (cooling). It can not be scaled up in any practical way.

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 > ..

i would think not. unless waves can be tuned to cancel out background radiation, but that would only stop it from heating up more.

Besides freezers I donโ€™t think thereโ€™s any technology we know that could do this on a wide range of substances. But freezers are neat - they move heat from the inside to the outside and as they are insulated they can reach temperatures 40-50 degrees (Celsius) under their surroundings

You can get "freezers" that will put part of their inside down to 250+c below their surroundings. (Helium cryocoolers)

This is cool! Where do I get one and whatโ€™s the power usage?

Semiconductor mfg firesales.

Or if you want to spend the 20+k you can buy from the manufacturer.

Oh power usage.... that depends how much you need to cool down, and what setup you have. But usually they're 3 phase and lots of amps......

Given how much about science we still have to learn, I would say it is a distinct possibility. If you want something cheap and easy to use like a microwave to do this though, I highly doubt we'd see that possible for the next 30-40 years at minimum.

https://m.youtube.com/watch?v=Cb_s_8aEVuQ

They trial'd something similar on the snowpeircer train instead of treats like ice cream for good behaviour they froze your arm off for being naughty lol

It's a good job they didn't have that when I was at school because I'd be just a head and torso now lol

OP's mind is going to get blown when they learn about a freezer.

Not really proven. It's theorized to be possible, but nothing emits cold that we know of in the same way. Microwaves, use waves (citation needed) to heat up the food, cold to our know doesn't work the same way.

That's because cold doesn't exist as a thing. Cold is just a lack of heat. You can only take the heat out of something, not add cold to something.