It actually makes sense, doesn’t it? Heating the object adds energy constructively. In cooling, energy removed from one particle may in fact be absorbed again by neighboring particles, so it is not ‘efficient’. So I’d venture a guess at saying the object cools from outside until it is entirely cooled.
like to make something clean, you have to make something else dirty.
But the thing which is "dirtier" is the wider universe, where the energy you used to do that sorting has higher entropy.
At the scale of atoms and molecules in a gas, you can also sort them into high-energy particles on one side of a barrier and low-energy particles on the other side, and now there's a heat difference you can run a heat engine. This is totally a thing you can do with the right devices — but those devices will necessarily consume more energy than you get from a heat engine running on that heat difference.
If either red or blue were dirt, one of the sides is dirty, and the other is clean.
If neither red or blue were dirt, then nothing was dirty, it was just mixed up.
An individual molecule in an open system can freely exchange energy with its surroundings and can/does have a temperature.
When you start talking about individual molecules, atoms or particles the whole concept of temperature becomes very counterintuitive. Think of it as a substitute for motion or vibration if you wish and even that is grossly inaccurate (but less so...).
Maybe this will help: a gas in a container has a pressure and a density as well as a temperature, all of which are properties of the gas and not of the individual gas molecules. A single molecule that the gas is made up from does not have a density, it doesn't have a temperature and it doesn't have a pressure. What it may have though is a speed relative to something else, and when it hits the something else it may impart some energy relative to that speed difference.
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.
Without thinking about it I thought heat was kinetic energy. And I don't see how collisions would transfer kinetic energy in positive direction any better than negative direction.
I'm imagining a bunch of potential energy being stored in the fields at any given moment.
But also note the all mater you interact with is almost entirely comprised of empty space, despite the illusion of solidness at our scale.
But it makes sense as to why heating would potentially be faster than cooling.
So of course it can't be symmetric. Just like breaking a wine glass, reversing that process takes a lot more effort.
Of course I have no idea if the above makes any sense, it's just an "intuitive understanding" I somehow got.
Power to heat, waste is more heat (just not where desired?).
Power to cool is used to move the state of one side of the system to another, ideally open, side.
Though this does raise the question of if it's possible to cancel energy out. I think that's likely stopped by Heisenberg's uncertainty of measurements (and exactly matching them even when measured).
The intuition is that the heat pump is moving heat, as opposed to just generating it.
Thinking of entropy as a measurement of how had it is to describe a system is a safer analogy.
Gibbs free energy, or the energy in a system available for work is
∆Enthalpy - ∆Entropy * Temperature
Temperature and Entropy are independent properties of a system.
Same here. By analogy, while any chemical reaction is in principle reversible, the kinetics "forward" and "backward" are unlikely to be equally favorable.
Likewise, with atomic nuclei, fission and fusion tend to be favored under distinctly different conditions.
The article does mention "far from equilibrium." Could this be a caveat similar to "in mice"?
The symmetry between cooling and heating is only a linearization approximation, like also the symmetry between compression and expansion.
There is no surprise that there are scenarios when the approximations deviate too much from the actual behavior and cooling and heating are asymmetric (and also compression and expansion).
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.
Time does not "move." Yet we need to conceptualize it. So our language here gets sloppy. You can recognize this by using the modified "if time can move forward, it should be able to be stopped." The obvious incongruity of this defies the idea that we're attempting to impose ourselves.
In terms of Entropy, the universe does not _want_ to be hot, it _wants_ to be cold and empty. So, the finding is genuinely counterintuitive.
I'm not saying that that the universe doesn't want to cool off, just that it seems ok to think it would be faster to warm up than cool off.
Which would like a bunch of randomized almost undetectable energy near absolute zero. So, I'm out on a limb past my comfort zone here, but my working model is:
Higher temperatures mean higher velocities mean the particles are less likely to interact with other particles and so their amount of entropy decreases, they become more predictable, have fewer possible future states, than they had before.
The second law just implies that work energy will always escape the system as heat because heat always moves from space with higher temperatures to space with lower temperatures. In a sense the universe is trying to move the hot things away from each other because it wants to be cold.
Those people are journalists. For them, thermodynamics is something they never heard about. That's why they became creative. /s