Heat Rises

[Occasional Sage]

... at least, that's the aphorism we all know.

But what would happen if we made a small change, and instead cold sank? It's a little thing at first glance, but steam power would never have worked, to say nothing of how cooking would differ.

Playgrounders, what about our world would be different?

[TheThan]

*Dons steam punk attire*

I dunno about that. But I made a great discovery yesterday in the lab. I discovered liquid steam!

[Altair_the_Vexed]

We'd all be dead. Or rather, we'd never have existed.

If cold sinks, then the absolute coldness of space will be attracted to massive objects, like stars and planets, and we'll never have evolved - what with no chemical reactions taking place at near 0K.

Of course, if only cold fluid systems sink, rather than some imaginary substantial coldness, that'd be a slightly different matter.

[Erloas]

Well think on this, if water didn't have to be different and instead got more dense when solid (ie frozen) instead of less dense?

Bodies of water would freeze from the bottom up. Streams, rivers, and lakes would freeze completely, the top would freeze as air temperatures dropped, then those bits of ice would sink, and it wouldn't take long before all but the deepest in-land lakes were frozen completely through during the winter.

With the oceans as well, its not impossible to freeze ocean water, it just has to be a lot colder then fresh water. Once it started to freeze it would sink down really deep, past where the energy from the sun could warm it up at all. And since the oceans act as giant heat stabilizers for the planet, but would be frozen beyond the reach of the sun there wouldn't be any way to melt it, since our hot and cold cycles are completely dependent on the sun's energy.

And I'm not too sure on this, but I think the fact that frozen water is less dense then liquid water is one of the reasons the incredible pressure at the bottom of the ocean doesn't crystallize the water on its own.

[Worira]

Uh. There's no such thing as cold.

[Occasional Sage]

Uh. There's no such thing as cold.

Shhhh. We all spend our time dealing with fantasy and alternate-reality worlds. Why can't there be such a thing as cold?

[Weezer]

Well think on this, if water didn't have to be different and instead got more dense when solid (ie frozen) instead of less dense?

Bodies of water would freeze from the bottom up. Streams, rivers, and lakes would freeze completely, the top would freeze as air temperatures dropped, then those bits of ice would sink, and it wouldn't take long before all but the deepest in-land lakes were frozen completely through during the winter.

With the oceans as well, its not impossible to freeze ocean water, it just has to be a lot colder then fresh water. Once it started to freeze it would sink down really deep, past where the energy from the sun could warm it up at all. And since the oceans act as giant heat stabilizers for the planet, but would be frozen beyond the reach of the sun there wouldn't be any way to melt it, since our hot and cold cycles are completely dependent on the sun's energy.

And I'm not too sure on this, but I think the fact that frozen water is less dense then liquid water is one of the reasons the incredible pressure at the bottom of the ocean doesn't crystallize the water on its own.

That is all true but ice floating has nothing to do with heat rising, its all due to the unique crystal structure of ice which leaves what amount to tunnels of emptiness throughout the ice.

Back on topic if cold sank instead of heat rising, as someone said there would be no steam engine, and thus no railroad, no industrial revolution, and almost none of the technological advances of the last 200 years.


Uh. There's no such thing as cold.

Just like there's no heat? Merely more or less molecular motion relative to arbitrary "zero" points.

[Erloas]

That is all true but ice floating has nothing to do with heat rising, its all due to the unique crystal structure of ice which leaves what amount to tunnels of emptiness throughout the ice.

I know that, ice floating is pretty much exactly the opposite of heat rising, because heat rises because it is less dense then the same material cooler.

I was just pointing out that it is a highly unique (is there anything else that is the same? I don't know of anything) property that works exactly the opposite of everything else and is a key factor in life having been able to exist in the first place.

[The Demented One]

Uh. There's no such thing as cold.
Sure there is. It's the absence of heat.

[Thajocoth]

Sure there is. It's the absence of heat.

Interesting word: Coolth. It is the absence of warmth. Someone once told me that their D&D professor told them that, occasionally, it is easier to figure out some architectural stuff using the flow of coolth instead of the outward flow of warmth. Kinda like it's occasionally easier to model certain systems using the Earth as the center of the universe...

[Dvandemon]

Uh. There's no such thing as cold.

You sound like my friend, always shooting down my concepts. *continues to grumble angrily at close-minded know-it-alls*

Imagine, if you will, a world where everything is reversed, cold sinks and The stars are just points of darkness that drain the ambient light away. What other "thing" exist only due to the absence of others?

[Jimorian]

Because heat rises, cold DOES sink. You're postulating a world with absolutely no difference from our own. :smallconfused:

[ForzaFiori]

Because heat rises, cold DOES sink. You're postulating a world with absolutely no difference from our own. :smallconfused:

The difference being that currently, cold sinks because the heat is actively moving out of the way. What the OP is postulating is a world where the COLD is the active temp. Cold sinks, forcing heat up, rather than heat rising, forcing cold down. Therefor, steam and other such things would have MUCH less power than they do now.

However, I do not think it would be as bad as Weezer thinks. True, there would be no steam engine. But does any really think that if humans had dealt with this different idea for the entire length of the species, we wouldn't just design an engine running off coolth rather than warmth? The reverse of a steam engine in essence. This... Ice engine, if you will, would be what caused the industrial revolution.

[fknm]

Cold being the "active force" makes no sense, given that "cold" is simply a subjective interpretation of a relative lack of heat.

[Rutskarn]

But what would happen if we made a small change...

We all die, no exceptions.

We exist because every single thing in existence is the way it is. No matter how small a change you make, winding back the causality for it to be so will probably result in an entirely different universe.

[Erloas]

The difference being that currently, cold sinks because the heat is actively moving out of the way. What the OP is postulating is a world where the COLD is the active temp. Cold sinks, forcing heat up, rather than heat rising, forcing cold down. Therefor, steam and other such things would have MUCH less power than they do now.

However, I do not think it would be as bad as Weezer thinks. True, there would be no steam engine. But does any really think that if humans had dealt with this different idea for the entire length of the species, we wouldn't just design an engine running off coolth rather than warmth? The reverse of a steam engine in essence. This... Ice engine, if you will, would be what caused the industrial revolution.

Well keep in mind that most every method we have of creating electricity we use now comes from steam. Coal, Oil, and various other burning like waste, Nuclear, and even Solar. (the efficient solor plants direct the light to a single source to heat water, the direct photo-voltaic cells like in calculators and you see on some buildings are highly inefficient and don't come anywhere near efficient enough to be of any use on a large scale). About the only thing that doesn't is hydroelectric and wind (a few others like tidal movements, but nothing real wide spread or even close to common).

But since, as mentioned, hot and cold don't exist in a scientific sense, they are just ways of describing a level of energy with "hot" having more energy then "cold". In this case any change in energy will cause movement and that movement is what is used to create power. So long as changing the amount of energy in (heating or cooling) the liquid created movement, you could use that to make power. With how things are now, it is easier to add energy to a system then it is to take it away. However if "cold" where the more active state of matter then it would be easier to do that because the universe would have to work in such a way that that was the case if the premise of the question is to make any sense. And in reality all you are actually changing is a humans preception of that energy, making more energy feel cold instead of hot. Because more energy is more energy. You can't actively pull off energy, you can just create a system that allows that energy to escape more easily. You can't force energy out, but you can force energy into a system.

The way we cool now is by creating a system that facilitates the transfer of energy away. Its one of the reasons why it is much easier to heat thinks then it is to cool them. We've been able to create heat for thousands of years, we've only been able to create cold for a hundred or so. (prior to that we could just move cold)

[Ravens_cry]

Cold being the "active force" makes no sense, given that "cold" is simply a subjective interpretation of a relative lack of heat.
Irrelevant. This thought experiment is imagining a world where that is simply not the case.

Infinitely flat planes are impossible. Does that prevent Flatland from being a useful analogy for thinking about dimensions and relativity?

[Solaris]

Irrelevant. This thought experiment is imagining a world where that is simply not the case.

Infinitely flat planes are impossible. Does that prevent Flatland from being a useful analogy for thinking about dimensions and relativity?

It always struck me as amusing when people demonstrated an inability to grasp the whole point of thought experiments.

[fknm]

Irrelevant. This thought experiment is imagining a world where that is simply not the case.

Infinitely flat planes are impossible. Does that prevent Flatland from being a useful analogy for thinking about dimensions and relativity?
Except that being not the case doesn't exist, unless you want to change the meaning of the words hot and cold.

Hot means that something has thermal energy. Cold means it does not. For "cold" to be having energy would be a redefinition of language, at which point having any discussion is pointless.

[Dvandemon]

Cold being the "active force" makes no sense, given that "cold" is simply a subjective interpretation of a relative lack of heat.

And now heat would be the subjective interpretation of a relative lack of heat. You're not really paying attention to what Forza is saying.


Irrelevant. This thought experiment is imagining a world where that is simply not the case.

Infinitely flat planes are impossible. Does that prevent Flatland from being a useful analogy for thinking about dimensions and relativity?

This ftw, the fact that it simply wouldn't work is not the subject, please try to grasp that. It is a thought experiment after all and shouldn't cause any frustration, just try to wrap your head around illogical.

[Jimorian]

It's not that thought experiments aren't cool, it's that this isn't a thought experiment. Cold sinking and heat rising are exactly the same definition.

In fact, the only reason heat rises is the application of gravity on the denser cold material, so the more logical basis for the real world physics explanation is what the OP is proposing. Just as saying a vacuum does NOT suck things, but that the higher pressure on the other end pushes it instead.

The talk of steam engines not operating has nothing to do with whether heat rises or sinks, it's a result of energy flow from hot to cold, and if the heat was on the "bottom" there wouldn't be any change.

What would be a thought experiment would be treating cold as a property in and of itself separate from the lack of heat, or postulating that cold rises, or any number of situations that lead to a different set of operating rules for the world.

[madtinker]

Heat doesn't rise, but hot air does. In that respect, they are the same thing from different reference points. As has been pointed out, hot air displaces heavier cold air (or dense cold air displaces lighter warm air), but heat (internal thermal energy, or average kinetic energy of molecules) doesn't really rise or fall.

[Ravens_cry]

It always struck me as amusing when people demonstrated an inability to grasp the whole point of thought experiments.

And what is the point of a thought experiment, oh wise and learned master. Teach us your ways so that we may benefit from your wisdom, if not your condescension.:smalltongue:

[Fifty-Eyed Fred]

Scientific and mathematical types always baffle me. From the perspective of the arts, of course cold is a thing; it's the opposite of heat. You can feel cold. The concept of cold actively sinking is not a large stretch of the imagination, either. :smallcool:

[thubby]

Scientific and mathematical types always baffle me. From the perspective of the arts, of course cold is a thing; it's the opposite of heat. You can feel cold. The concept of cold actively sinking is not a large stretch of the imagination, either. :smallcool:

it would be like saying vacuum is a thing, and that it spreads. while a certainly don't mind playing with the idea, it's subject to horrible fridge logic.

[Fifty-Eyed Fred]

Of course a vaccuum is a thing - it's the utter absence of matter, correct? :smallcool:

[Erloas]

Of course a vaccuum is a thing - it's the utter absence of matter, correct? :smallcool:

How can a thing be defined as the absence of things? Vacuum is simply lower pressure in one area compared to another. You can create a vacuum that is at 100psi (compared to atmospheric pressure) if the system you are attaching it to is at an even greater pressure.
Of course it does tend to be a matter of perspective, since in most cases its only really called a vacuum if it is less then atmospheric despite the fact that the concepts involved don't change at all. Of course "atmospheric" pressure would also change for any other planet you choose to visit

[Fifty-Eyed Fred]

The concept is there; the vaccuum exists. It is therefore a 'thing'. It's there and it can be observed. It doesn't matter if it comprises particles or anything like that. Cold is also a 'thing'; it can be felt and is the opposite of heat.

But as I said earlier, I'm coming at this from the perspective of an English student, not a scientist or a mathematician.

[Erloas]

Well "thing" is such a technical term...

[Fifty-Eyed Fred]

Indeed. :smalltongue:

[neoseph7]

First, Vacuum isn't actually nothingness. In addition to the ambient energy and virtual particles that would be found in a hypothetically "perfect" vacuum void of any matter, actual vacuum found in outerspace has a thin layer of various gases and whatnot with a temp of around 3 Kelvin if I recall correctly.

Second, it is perfectly reasonable to define nothingness as the absense of something. Definitions should, to an extent, make sense to those reading it. Without any kind of true nothingness ever seen but plenty of systems with something (x) and a little less than something (x-1), it is a matter of convienece to define vacuum as nothingness as the loss of something from something (x-x). Since we are for the most part familiar with something but completely unfamiliar with true nothing.

Onto the concept of cold being the standard instead of heat. It makes no difference what so ever. Just like it doesn't matter which polarity we use to describe electric current, refereing to cold as a substance and heat as the absence there of is just as valid as saying that heat is a substance and that cold is the lack there of. Both concepts are relative to each other, and you can only have a significant change by altering their relationship. Like by saying that cold rises and hot falls. That would totally frak things up.

Thermal Energy (heat) is a measure of the kinetic energy of the molecules that make up a body. Heat "flows" through these particles hitting the particles of adjacient matter. It would be mildly more tedious but still valid to instead define cold as the lack of motion in a body, in which case hot objects would suck the cold out.

To make an example of a real world phenomina, let us look at semi conductors. Semiconductors work by the changing of electron-electron hole pairs. Electron holes are the absence of an electron in a lattice. In a laboratory sufficiently prepared (costing 1000GP in expenisive material components and regeants) one can "see" the electron hole moving around as if it were a paricle of its own. It is perfectly reasonable to give a velocity and other defining physical qualities to something that isn't actually there.

Gaps in traffic are another good example if that helps. Electrons have a negative charge, but the flow of electrons through a circuit (current) has a positive charge. It doesn't matter.

Depending on how one views a situation, what one usually has is a comparison for the complex difference engine that is our brain. Heat all by it lonesome is pretty meaningless without the absense of heat as a comparison. Which we define as positive and negative is largely irrelivant.

[Ashtar]

If you want some crazy physics in which this could happen, have a look at Exotic matter (http://en.wikipedia.org/wiki/Exotic_matter), where gravity pushes things apart and similar electrical charges attract. :)

For a theoretical model of vacuum, have fun understanding the Dirac Sea (http://en.wikipedia.org/wiki/Dirac_sea) theoretical model of vacuum. Also, we can bring out the really funny Vacuum energy (http://en.wikipedia.org/wiki/Vacuum_energy) to complete the confusion.

[Altair_the_Vexed]

If you want some crazy physics in which this could happen, have a look at Exotic matter (http://en.wikipedia.org/wiki/Exotic_matter), where gravity pushes things apart and similar electrical charges attract. :)

For a theoretical model of vacuum, have fun understanding the Dirac Sea (http://en.wikipedia.org/wiki/Dirac_sea) theoretical model of vacuum. Also, we can bring out the really funny Vacuum energy (http://en.wikipedia.org/wiki/Vacuum_energy) to complete the confusion.
This hurts my poor brain. :smallfrown:

[Zeb The Troll]

My step-dad once confused me and my siblings about what was going on by insisting on calling flashlights "dark suckers". He explained that "dark" was caused by an excess of dark particles and that a flashlight served to absorb these obscuring dark particles and reveal whatever was hidden, thus "dark sucker" was a more accurate term for them. :smallcool:

[Runestar]

Cone of absence of heat just doesn't have the same ring to it...:smalltongue:

[2xMachina]

It's not that thought experiments aren't cool, it's that this isn't a thought experiment. Cold sinking and heat rising are exactly the same definition.

In fact, the only reason heat rises is the application of gravity on the denser cold material, so the more logical basis for the real world physics explanation is what the OP is proposing. Just as saying a vacuum does NOT suck things, but that the higher pressure on the other end pushes it instead.

The talk of steam engines not operating has nothing to do with whether heat rises or sinks, it's a result of energy flow from hot to cold, and if the heat was on the "bottom" there wouldn't be any change.

What would be a thought experiment would be treating cold as a property in and of itself separate from the lack of heat, or postulating that cold rises, or any number of situations that lead to a different set of operating rules for the world.

I agree with this. Cold air sinks, pushing the hot air up. The hot air doesn't get anti-grav to rise up. Cold air is denser, thus gravity pulls it down harder, forcing hot air to rise.

[Tirian]

The concept is there; the vaccuum exists. It is therefore a 'thing'. It's there and it can be observed. It doesn't matter if it comprises particles or anything like that. Cold is also a 'thing'; it can be felt and is the opposite of heat.

But as I said earlier, I'm coming at this from the perspective of an English student, not a scientist or a mathematician.

The important fact is that it cannot be measured. Cake is a thing; you can have one or three or whatever. But if you have no cake, you can't measure exactly how much cake you don't have.

That's the same difference between heat and cold, light and dark, and matter and vacuum. The latter exist only philosophically as concepts in physics and your discussion is already off-track if you confuse them with their subjective counterparts.

[Kcalehc]

But there is no cold. There is only heat or no heat (and 'no-heat' is extremely rare if not impossible). Cold is a relative term to describe something that has less heat than something else, not an absolute term to describe a certain absense of heat.

for example, ice (which many would agree is 'cold') is colder than water, because it contains less heat. But it still contains heat, just not as much. And liquid nitrogen is colder still, but still contains heat. Absolute 0 being, possibly, impossible to reach due to a certain thermodynamic law.

Vacuum is not a thing, it is infact nothing. Or not anything. Or even a not-thing. You cannot observe it, at least not directly, though it may be possible to observe where a vacuum is by where there is nothing else. But then a pure/total vacuum does not exist anyways (virtual particles and such...).

Language is such a clumsy medium to explain how things work.