Also, water that is heated reaches cooler temperatures faster: https://en.wikipedia.org/wiki/Mpemba_effect
Scientists report asymmetry between heating and cooling
31–40 of 139 posts
Re: Scientists report asymmetry between heating and cooling
#32Re: Scientists report asymmetry between heating and cooling
#33> 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.
Meh, if self-assembling, self-repairing materials forming a swarm of nano bots was going to take over the world it would have already happened elsewhere in the universe and proliferated everywhere by now. instead we have biology. The actual dominate force in our dimension that did proliferate.
Why would that apply to synthetics but not to biologicals?
Re: Scientists report asymmetry between heating and cooling
#34I 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.
I think the human mind tries to impose order or symmetry on things.
Like, "if time can move forward, it should be able to move backwards"
I kind of think of explosions and entropy. I just don't see there being an equivalent reverse phenomenon. Even shooting a bullet into icewater or something colder seems like it would cool off many orders of magnitude slower. maybe I'm wrong.
Re: Scientists report asymmetry between heating and cooling
#35My 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?
Re: Scientists report asymmetry between heating and cooling
#36I 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.
I'm confused too. Isn't this what entropy is about? Or is it a more fine grained version of macroscopic quantity that is entropy?
Re: Scientists report asymmetry between heating and cooling
#37Earlier quoted context omitted.
Would you care to share for those of us who haven’t written a grant application before?
It’s the biggest stretch possible without it being technically dishonest. Everyone knows it: the researchers know it and gag a little as they write it, and the grant reviewers know it but pretty much require it without really ever saying that they require it (competitive landscape and all).
it exhibits a capacity to be full of shit with a straight face, which makes grant funders happy so grant reviewers view it as job security
Re: Scientists report asymmetry between heating and cooling
#38> 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!"
In lots of published papers there is some kind of call-out for the requirement of future research.
https://scholar.google.com/scholar?hl=en&as_sdt=0%2C5&q=more...
A sentence like that or a variation thereof is part of the 'dance' around funding.
Re: Scientists report asymmetry between heating and cooling
#39We knew about this: some kinds of heating can affect all the molecules, but cooling generally only those colliding with the walls.
Re: Scientists report asymmetry between heating and cooling
#40I 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.
> 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.