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Manipulating Heat Like Light
An anonymous reader writes "A new technique allows allows 'thermocrystals' to be created that can manipulate heat (a vibration of the atomic lattice of a material). Predicted manipulations include the ability to selectively transmit, reflect or concentrate heat much like light waves can be manipulated by lenses and mirrors. 'Heat differs from sound, he explains, in the frequency of its vibrations: Sound waves consist of lower frequencies (up to the kilohertz range, or thousands of vibrations per second), while heat arises from higher frequencies (in the terahertz range, or trillions of vibrations per second).' Applications range from better thermoelectric devices to switchable heat insulating/transmitting materials (abstract). Perhaps this will result in better cooling/heating mechanisms or more efficient engines."
It's a shame there isn't a new technique that allows allows silly typos in summaries to be corrected before publishing.
"heat (a vibration of the atomic lattice of a material)" no shit sherlock...
Maxwell's Demon?
Napolean already gave Fourier the patent on that.
I wonder if you could use this to concentrate low levels of heat and generate electricity from it. Not only would you be able to get energy out of (almost) nothing, (albeit, probably not much), but you could cool an area without producing a lot of waste heat.
How did this one get missed? Fusion's biggest problem is heat management.
Thermal Diodes: Hook this to a solar collecting sterling engine for a considerable performance boost.
That sounds like passive Heating & Air conditioning. Maybe society will use technology to reduce its power consumption overall.
Science & open-source build trust from peer review. Learn systems you can trust.
This is just EM radiation that at our temperature and materials just happens to turn into heat easily.
These crystals aren't heat sinks. The MIT lab is creating a "heat" that is actually just really fast sound. This can then be manipulated with their special thermocrystals. Now, if they can create a way to turn normal waste heat into this "fast sound" heat, we'll open up a wealth of practical applications.
Occasionally living proof of the Ballmer peak.
From TFA:
The crystals could also be used to create thermal diodes: materials in which heat can pass in one direction, but not in the reverse direction. Such a one-way heat flow could be useful in energy-efficient buildings in hot and cold climates.
Other variations of the material could be used to focus heat — much like focusing light with a lens — to concentrate it in a small area. Another intriguing possibility is thermal cloaking,
Some of the speculative uses seem pretty interesting. To date it is only 40% efficient at some of these tasks, but that's not bad for starters.
These things sound like beginnings of heat circuitry components. The method involves making alloys of silicon that incorporate nanoparticles of germanium in a particular size range, and layering these thin films. If they can find a dynamically controllable switch structure you could build most of the necessary components for simple circuits.
Then you run into this sentences from TFA:
Heat also spans a wide range of frequencies, he says, while sound spans a single frequency.
Wow. Journalism student I'm guessing?
Sig Battery depleted. Reverting to safe mode.
Sound is pressure waves. Heat, or more accurately, infrared, is electromagnetic radiation.
They are so vastly different, far beyond just frequency, that I'm not sure what the person who wrote the summary is smoking. :)
One of the major problems with creating extremely powerful fan-less processors for mobile devices is heat. Heat problems increase to a square of scale variations when miniaturizing circuitry. If control of heat can be directed to increase the flow of heat away from NEMS and microchips adequately, we could see mobile devices that could compete with the most powerful current desktop processor.
We should learn what we need to know about issues, before we decide what we need to feel about them.
But can it concentrate the heat away from my beer without reducing the volume or pressure. I like the tiny bubbles...
I haven't read TFA but isn't radiation by defination, heat that moves over open space? If you can manipulate heat, then couldn't you manipulate radiation, and thus build shields for deep space travel?
No. Heat is not Infrared radiation and Infrared is not heat. Heat is vibrational energy in matter. In other words, it is the energy in the vibration of the atoms and molecules. If something is hot enough, it can cause electrons to jump to higher shells temporarily. When they fall back to the ground-state shell, they emit a photon. This photon has an energy level corresponding to the Infrared spectrum. When this photon, at the Infrared spectrum, strikes matter, it can induce vibrational energy, i.e. Heat, in the molecules/atoms of the substance that is absorbing the photon.
Heat is light.
On Slashdot!
Parent is wrong.
It's only a "law" because we do not yet know how to break it.
I, for one, look forward to the day (year, century...) when we decide that it's an obsolete principle. Until we actually know all the rules of the game, all the interactions, all the api of the universe... we cannot know that anything is truly a "law of physics". We can speculate, postulate, investigate, narrow-in-on, or disprove, but never really affirm.
(Which is not to say that this specific mechanism shows any promise, just that some mechanism might exist in the future.)
I won't join Slashcott. OTOH, If Beta goes live, I just won't be back until it's fixed. Sorry Dice.
Face Palm!
Heat is vibrating atoms. (Or slightly more accurately, banging off each other randomly like billiard balls.) Some of that energy gets converted and emitted as radiation, and radiation can be absorbed and converted to heat, but that does NOT make them the same thing.
I won't join Slashcott. OTOH, If Beta goes live, I just won't be back until it's fixed. Sorry Dice.
...but is this a step towards a working Thermal Discouragement Beam?
"So after all this, you make my case for me. To end this stalemate, you must die..."
Usually the main problem with press release science is that it has nothing to do with the real science behind it. Probably, there's an MIT professor embarrassed to show up to colloquia right now.
This press release is talking about acoustic metamaterials. The scientific description in the press release is bad, very bad, but one thing they got dead wrong is that this is not new.
Windows that ventilate but keep the heat inside would be a great invention for continuous fresh air in the home, one of the most air polluted places in most people's lives from day to day.
Now that it's been said, heat is just a (higher) frequency of sound, and heat is visible in infrared frequency range of light, does that mean sound is also visible in some other (lower) wavelength? What would that make the cosmic microwave backround or the microwave radiation of space dust? Are they observations of tones of music, the music of the exploding Big Bang and the coldness of space dust? "OMG," man of the future says, "I can see sound!" lol Oh, [sigh].
So what does this do to Carnot's Law?
Does it sort of make it irrelevant?
Can it overcome the constraints of Carnot's Law? (which is what the original article posting implies)
Or can this new approach only function within the limits of Carnot's Law?
What do we call this new approach, anyway?
Thermoptics?
It sounds like they are making a resonant structure to reduce the bandwidth of the heat, which means heat generated from ordinary sources will not easily flow into these crystals. Though it sounds like they can fairly efficiently manipulate it once its in the devices, its not very useful if you can't get heat into it in the first place.
Very interesting. Dont you think It always sounded weird when you were in class and the teacher claimed Energy is partially converted partially lost as heat. Certanly these thermocrystals should be kept an eye on. For funding, research and peer finding please refer to the non-profit Aging Portfolio.