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.
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 > …
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.
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
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.
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 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.
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.
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.
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