this post was submitted on 14 Sep 2023
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[–] UnicodeHamSic@hexbear.net 3 points 1 year ago* (last edited 1 year ago) (2 children)

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.

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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?

'projecting' energy is kinda easy... 'sucking' energy is difficult

[–] qwertyqwertyqwerty@lemmy.world 2 points 1 year ago (1 children)

The reverse microwave. I heard you need a LOT of freon.

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[–] muddi@hexbear.net 2 points 1 year ago

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

[–] HawlSera@lemm.ee 2 points 4 months ago

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.

[–] hogunner@lemmy.world 2 points 1 year ago

I don’t know if it’s a stupid question or not but I have been wondering this myself for years. :)

[–] ebits21@lemmy.ca 2 points 1 year ago* (last edited 1 year ago) (4 children)

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

You can’t just remove heat by adding electromagnetic energy. Absorbing energy from the electromagnetic radiation makes heat.

Edit: whelp, TIL

[–] peopleproblems@lemmy.world 2 points 1 year ago

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

[–] ironhydroxide@partizle.com 1 points 1 year ago

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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[–] leanleft@lemmy.ml 1 points 9 months ago

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.

[–] maniel@lemmy.ml 1 points 1 year ago* (last edited 1 year ago) (3 children)

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

[–] Natanael@slrpnk.net 2 points 1 year ago

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.

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