submitted 8 months ago by [email protected] to c/[email protected]
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[-] [email protected] 295 points 8 months ago* (last edited 8 months ago)

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.

[-] [email protected] 156 points 8 months ago

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!

[-] [email protected] 73 points 8 months ago

Hah! My ChatGPT bot did 60 slides in 90 seconds, and submitted it hours before yours. See YOU in court!

[-] [email protected] 19 points 8 months ago* (last edited 8 months ago)

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)!

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[-] [email protected] 65 points 8 months ago

Technically that's already a thing. It is pretty expensive compared to a normal refrigerator though...

[-] [email protected] 13 points 8 months ago

Easy, just invert the polarity of the microwaves

[-] sock 14 points 8 months ago

i turn the microwave upside down

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[-] [email protected] 143 points 8 months ago

There’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.

[-] [email protected] 43 points 8 months ago

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

[-] [email protected] 22 points 8 months ago

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.

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[-] [email protected] 116 points 8 months ago

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.

[-] [email protected] 32 points 8 months ago

Maybe we could start manufacturing mini black holes to build the dark bulbs!

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[-] [email protected] 93 points 8 months ago

We have that, it's called a fridge, and then there's a freezer for making things frozen.

[-] [email protected] 33 points 8 months ago

But a fridge is the opposite of an oven. Some kind of flash freezing would be like the unmicrowave.

[-] [email protected] 51 points 8 months ago

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".

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[-] ohlaph 14 points 8 months ago

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

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[-] Coreidan 71 points 8 months ago

Yup. It’s called a refrigerator

[-] [email protected] 15 points 8 months ago

Get out of here future sifi man.

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[-] [email protected] 61 points 8 months ago

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 “light” 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 they’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 that’s even colder—in short, a refrigerator.

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[-] [email protected] 54 points 8 months ago
[-] [email protected] 25 points 8 months ago

There are devices that will cool a drink (can of soda or a beer) to 'ice cold' ( I assume something like 5°) 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.

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[-] [email protected] 52 points 8 months ago


[-] Meuzzin 48 points 8 months ago

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

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[-] [email protected] 44 points 8 months ago* (last edited 8 months ago)

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.

[-] [email protected] 25 points 8 months ago

Funny note- the way we actually get things to near absolute zero, is by shooting it with lasers.

[-] jumperalex 19 points 8 months ago

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!!!

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[-] bi_tux 42 points 8 months ago

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

[-] [email protected] 17 points 8 months ago

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

[-] [email protected] 25 points 8 months ago

My god where does it end with you beer snobs??

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[-] [email protected] 41 points 8 months ago

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.

[-] [email protected] 15 points 8 months ago* (last edited 8 months ago)

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

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[-] [email protected] 40 points 8 months ago
[-] [email protected] 35 points 8 months ago

So this isn't fully what you're looking for, but if you want to cool something more quickly, wrap a wet paper towel around it and stick it in the freezer.

Water has a higher rate of heat transfer than air, so it'll speed up the cooling. Just make sure to check on it occasionally so any sodas you put in don't explode

[-] [email protected] 13 points 8 months ago

I expect this post in a couple days: "How do I remove a paper towel that is frozen to my bottle of wine?"

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[-] MTK 35 points 8 months ago

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.

[-] [email protected] 25 points 8 months ago

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

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[-] [email protected] 31 points 8 months ago

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

[-] [email protected] 29 points 8 months ago

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

[-] [email protected] 24 points 8 months ago

Liquid nitrogen is kinda dangerous for consumer appliances.

[-] [email protected] 21 points 8 months ago

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

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[-] Jimmycakes 19 points 8 months ago

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

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[-] [email protected] 19 points 8 months ago

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

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[-] [email protected] 18 points 8 months ago

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:



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[-] [email protected] 18 points 8 months ago

Cool question. I‘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.

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[-] withabeard 18 points 8 months ago

Blast freezer. It's about as close as we'll get any time soon. Not an affiliate or anything, just googled and found this bugger (about microwave sized).


[-] arin 16 points 8 months ago

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

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this post was submitted on 14 Sep 2023
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