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Does this mean ideal building design is as cool as possible and using energy for heating?
I'm not an expert at all, but from my understanding, the ideal building is one that has so much insulation that its interior is kept at a set temperature with very little cooling and heating needed.
My first thought upon reading the article was that absolute zero bounds coldness whereas there is no limit to how energetic a particle or bulk can be. Am I on the wrong track?
> While no immediate practical applications exist, the researchers envision enhanced efficiency in micromotors, microscale cargo transport, and materials that can self-assemble or self-repair. Everyone who has ever written a grant application will recognise this wording.
I'm curious what the meaning behind the recognition is. Is it "this has applications potentially anywhere!" Is it actually code for "very dangerous military applications, DARPA please pay attention to me!"
Does this mean ideal building design is as cool as possible and using energy for heating?
Depends on the climate. Houses built in southern Italy are like that (white paint, shutters on windows, ...) But in the Sweeden the opposite, optimize for heat.
Not that much. As you mentioned just above, shutters are a layer of insulation. In Sweden, they have big glass windows and no shutters. The purpose is clearly to get the tiny bit of daylight in winter for health sake, but in terms of insulation, it would be better to have shutters, and smaller windows.
I always feel a little stupid or strange reading a lot of these science headlines and introductions. I wasn't aware that people considered there to be a symmetry between heating and cooling. I thought that the entire point of thermodynamics is that they are asymmetric. Even the article mentions that it's been known that heating is more efficient than cooling.
Earlier quoted context omitted.
> On the other hand, cooling at the microscopic level involves the release of energy from individual particles, resulting in a dampening of their motion. This process corresponds to the system losing energy, leading to a decrease in the intensity of particle movement. It actually makes sense, doesn’t it? Heating the object adds energy constructively. In cooling, energy removed from one particle may in fact be absorbe…
But isn't that passing on of energy from one particle to the next, just conduction? Why wouldn't it apply in the same way when heating?
Now in solid materials, that neighbour is always there to distribute any energy to everyone equally. But from solid to gas, there is only the surface and a gases density is lower, so the transfer propability shrinks again.
Earlier quoted context omitted.
Microwaves penetrate the interior of objects (outside of metal) that are in their Faraday cages, leading the internal temperature of those objects to rise dramatically. Blast chillers work like reverse ovens, from the surface to the interior.
Microwaves target the resonant frequency of intermolecular hydrogen bonds and impart vibration. It's a very special mechanism that doesn't really lend itself to this sort of analogy.
Earlier quoted context omitted.
> On the other hand, cooling at the microscopic level involves the release of energy from individual particles, resulting in a dampening of their motion. This process corresponds to the system losing energy, leading to a decrease in the intensity of particle movement. It actually makes sense, doesn’t it? Heating the object adds energy constructively. In cooling, energy removed from one particle may in fact be absorbe…
Heating and cooling are rarely nicely split up in time. While you're heating something it is also cooling and while you're cooling something it is also warming up. This usually limits your ability to heat something up or to cool it because at some point these two are in balance.
The phys.org article and science paper text are both impenetrable for different reasons (though I don't blame the paper). Can anyone explain this result like I have a college degree but not in physics? I'm especially interested in what the actual difference in "microscopic" process is between heating and cooling.
They experimentally demonstrated that it takes significantly more energy to move a microparticle the same distance when cooled than the amount of energy it would take when heated.
Earlier quoted context omitted.
Heating and cooling are rarely nicely split up in time. While you're heating something it is also cooling and while you're cooling something it is also warming up. This usually limits your ability to heat something up or to cool it because at some point these two are in balance.
No. Put a cold thing into something hotter and the thing will heat up without cooling.
like to make something clean, you have to make something else dirty.