Microwaves can transform a frozen pizza into hot, melted goodness in four minutes flat, but they can’t rescue your melted ice-cream sundae. To cook food, a microwave oven converts voltage into high-frequency electromagnetic microwaves. The molecules in food—especially water and fat—absorb this energy and wiggle at high speeds, causing them to heat rapidly and warm the surrounding food. Although quickly turning leftovers cold would be handy, this is a one-way operation, explains David Pozar, a professor and microwave expert at the University of Massachusetts. Microwaves can only speed up atoms, not slow them down.
Scientists do have a high-tech method for slowing atoms, however: lasers. Shoot a moving atom with a laser, and it will absorb the laser’s photons and re-emit them every which way, causing the atom to hold nearly still. Placing an atom at the junction of multiple beams can slow its momentum in all directions, decreasing its energy and cooling it.
This drops an atom’s temperature a couple hundred degrees Fahrenheit—much colder than anything you’d want to put in your mouth—in less than a second. But because it works most efficiently on low-density gases of atoms of a single element, physicist Mark Raizen of the University of Texas doesn’t think it will be useful for cooling food anytime soon: “Not unless you can subsist on a thousand sodium atoms.”
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.


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I want to try ice cream that's frozen at -200 F. I'd probably lose my tongue in the process, but it'd be worth it. I sceam, you scream, we all scream for ice cream!
If you cooled a few thousand atoms by 200 F, what would that do to the material those atoms are embedded in? I'm sure the rate of thermal transfer would vary from material to material, but how many atoms would we need to cool by 200 F in order to achieve a 10 F drop in an ounce of material?
this is Very Kool
could use a liquid nitrogen bath.
Why this? We already have freezers and Meat lockers. Isn't this the same idea?
@aerosphere: the (unwritten) idea is that since microwaves heat food quickly, can they be used to freeze or cool food quickly. Freezers, meat lockers, etc. cool food very slowly.
@Merc: "But because it works most efficiently on low-density gases of atoms of a single element"
So it isn't going to be cooling any ounce of material any time soon.
This is an interesting question. basically we are talking about a dampening field as oposed to an exciting field. It may be possible to dampen the molecules vibration if you knew the position and momentum for each molecule and were able to apply a micro wave at exictly the right time to push aginst its existing motion. Possibly this could be revealed by MNR. The computational power required would be huge and the response time of the system would need to be in nano seconds.
However. If you were to target the molecule with pulses of coherent microwaves and after each pulse begins you measured the excitation of the molecule. if it has incresed you stop excitation. If it has decreased you continue and measure again. You keep targeting the molecule until an increase is measured. In this way you solve the problem of determining the phase of the vibrating molecule.
superdub - you're a funny guy - Heisenberg pretty much put the knowing the position and momentum thing to bed. Frankly, I think this whole article should be put to bed, the answer to the question "Can microwave technology be used to make food cold?" is NO. I think the name of this publication should be changed from POPULAR SCIENCE to POPULAR NON-SCIENCE or maybe just NONSENCE for short.
This article is like saying in big bold letters CAN ASPIRIN BE USED TO CURE CANCER? then the article says "no it cannot"
raise my hopes for a freeze-ray
Microwaves can chill down food? Sure, just as God made little green apples. Problem is high-intensity microwaves resonate within the water molecule to heat it up to a boil, exactly what space solar power satellites that beam down solar energy from orbit will do to plants, animals and people, as described in the book Sunstroke by David Kagan.
Interesting article, though.
Heisinbergs uncertanty principle is relevent over much smaller scales than meaasuring the vibration of a molecule especially a large molecule. Regardless the second method does not need to know the molecules position. You just fire microwaves at the molecule. If its in phase it will incresae the vibration so you stop. If its out of phase you will dampen the molecules vibration so you continue. the problems are resolving the molecule in the first place in order to measure its vibration. And being able to take measurements and control the beam fast enough to be able to make it work.
@ davek01521, Jedigeek93, and zuggerjack.
Did anyone of you even read the article?
I believe rather than using actual microwave ovens to chill food, the idea was to do something similar (i.e. chilling food quickly as apposed to heating) with a different technological process altogether. I don't think a few of you are actually grasping the concept of what they've done. They didn't use microwaves to cool the atoms, they used lasers to slow absorb their heat energy; therefore cooling them.
Skies - That's the point. The article should be titled "Can Lasers be used to make food cold?" They sucker you in with a non sequitur then further insult your intelligence by switching topics.
Ah, well when you put it that way, yes.
But I still think that the author meant the idea behind microwaving rather than actual microwaving. I guess if you're expecting microwaves in an article about lasers, yeah, you'd be disappointed. Hah.
This can be done with microwaves, but in an opposite fashion. That is, to use only a single wave.
A high magnetic field is produced, and then reversed, once. That produces a reduction in temperature.
This can be done more than once, but how frequently you could do it before creating another effect is another question.
wow! someone thought of what i been thinking!..I been thinking exactly that and was planning on a design for it, hopefully i might find some way to design a freezer microwave, ..it would be soooo cool!
Since there's no such thing as cold, just lack of heat, you'd need to draw energy from the target. If it's warmer than your "emitter", you're faced with suckering the 2nd Law of Thermodynamics somehow.
The laser trick amounts to putting the collection of atoms in the minimum-node of a standing wave; to do the trick with a sundae you'd need all the elements in it to vibrate exactly alike. Quite a trick!
Oops, meant to say "if it's cooler than your emitter".
@People who think it's a stupid article:
In the print edition, this was in the Q&A section. The question was sent in by a reader. I think that not labeling the article "question from a reader" or something wasn't the greatest idea (since it makes you think that the question is rhetorical), but the article isn't pointless; it answered someone's randomly picked question.
The technology sounds cool. Anything to make ones life quicker and easier! I suppose getting the temperature just around freezing will be the tricky part.
www.massrealestatevoice.com
Wow!Very cool.I guess if you're expecting microwaves in an article about lasers, yeah, you'd be disappointed. Haha!
Interesting article, though.
Peter
www.twinsea-trade.com your ovens comparison
It will be no surprise when this technology becomes available. It is amazing how fast the world around us changes by the month. Even in Real Estate this is the case with new gadgets coming on the market all the time.
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Now, it is possible to produce cold with microwave oven !
http://www.youtube.com/watch?v=zyiOlqmMAgE
This film shows how it is possible, under certain conditions, to make this microwave oven work in a particular way to generate cold.
This is the microwave oven's hidden side !