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Scientists report asymmetry between heating and cooling

phys.org

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Re: Scientists report asymmetry between heating and cooling

#101

Post by rpmisms »

cmrx64 wrote: post #75
rpmisms wrote: post #12

Earlier quoted context omitted.

Considering that Brownian motion applies (chaotic movement, generally in liquids, caused by heat), yes, the market mirrors the laws of physics here.

The theorems of thermal kinematics derived apply to limited models with a quadratic energy potential, localized on a spatial manifold. is there any reason to believe the market is described by this sort of model?

Mirrors != described by. Plenty of non-physical phenomena mirror physical occurrences, and this is one of them.

Re: Scientists report asymmetry between heating and cooling

#102

Post by x86_64Ubuntu »

VMG wrote: post #76
geraldhh wrote: post #70

Earlier quoted context omitted.

the hot thing will get cooler. like to make something clean, you have to make something else dirty.

Is that true though? If I have say a box with mixed red and blue bricks and I sort them by color, both sides are "clean" now.

You've left out the entropy you've added to the universe by ordering the system. That entropy is in the form of wasted heat.

Re: Scientists report asymmetry between heating and cooling

#103

Post by abcc8 »

ijhuygft776 wrote: post #100
bmitc wrote: post #3

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.

I used to live in Florida and it costs me a lot more to heat the house than cooling it even though the outside temperature rarely went below 32F (and I kept the home at 74F in the winter and 78F in the summer)...

Were your heater and cooler equally efficient?

Re: Scientists report asymmetry between heating and cooling

#104

Post by Projectiboga »

ijhuygft776 wrote: post #100
bmitc wrote: post #3

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.

I used to live in Florida and it costs me a lot more to heat the house than cooling it even though the outside temperature rarely went below 32F (and I kept the home at 74F in the winter and 78F in the summer)...

AC is way more energy efficient, heat pumps too. They both move heat, rather than heat it with electric resistance heating. ACs move +-4 degrees of heat per watt of electricity used.

Re: Scientists report asymmetry between heating and cooling

#105

Post by bmitc »

extractionmech wrote: post #7
bmitc wrote: post #3

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.

> 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…

I'm not saying that it doesn't make sense. What I am getting at is that I thought this was already known.

Re: Scientists report asymmetry between heating and cooling

#106

Post by jvanderbot »

extractionmech wrote: post #7
bmitc wrote: post #3

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.

> 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…

Wait so hot objects have molecules with greater nuclear energy? This seems wrong. Are they emitting energy like radiation? I suppose that makes some sense, and would in fact support the asymmetry.

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.

Re: Scientists report asymmetry between heating and cooling

#107

Post by _a_a_a_ »

jvanderbot wrote: post #106
extractionmech wrote: post #7

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…

Wait so hot objects have molecules with greater nuclear energy? This seems wrong. Are they emitting energy like radiation? I suppose that makes some sense, and would in fact support the asymmetry. 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 can't see any mention or implication of 'nuclear' - where do you see that?

Re: Scientists report asymmetry between heating and cooling

#108

Post by Ma8ee »

tsimionescu wrote: post #82
Ma8ee wrote: post #68

Earlier quoted context omitted.

No. Put a cold thing into something hotter and the thing will heat up without cooling.

No. The outer layer of the hot thing will quickly heat up to the temperature of the hot medium, then it will cool down as is stays in contact with the middle layer, which will heat up itself. The same thing repeats in layers all over the object.

No, why do you think the outer layer will cool down? There will be heat transfer between the outer layer and the layer within, but at no point in time will the temperature of the outer layer be cooler than it was at an earlier point in time, so it will never cool down.

Re: Scientists report asymmetry between heating and cooling

#109

Post by Ma8ee »

wybiral wrote: post #91
Ma8ee wrote: post #68

Earlier quoted context omitted.

No. Put a cold thing into something hotter and the thing will heat up without cooling.

You mean putting cold ice cubes into a warmer drink doesn't cool it down?

The ice cubes will only get warmer and will never get cooler.

Re: Scientists report asymmetry between heating and cooling

#110

Post by Ma8ee »

darkerside wrote: post #83
Ma8ee wrote: post #68

Earlier quoted context omitted.

No. Put a cold thing into something hotter and the thing will heat up without cooling.

At the boundary between water and air, molecules are constantly snapping back and forth between being liquid and vapor. It's just that an equilibrium has been reached that makes the system appear static.

A molecule isn’t liquid or vapour. A molecule doesn’t have a temperature.
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