NationStates Jolt Archive

Perhaps this question is self-defeating in its logic, but I'll ask it anyway, since I've been pondering it for a while.

I've heard it said that a fair paraphrase for the 2nd law of thermodynamics is that "order tends towards disorder", or basically, everything is winding down.

Before anyone makes the jump, I am in no way talking anything about creation vs. evolution here. With that said:

If order tends towards disorder, how is it that anything LIKE a physical "law" exists in the universe as a constant? Wouldn't the existence of constants in the universe bring this law into question? I'm no physicist; I'm just asking this out of curiosity.

"Order tends toward disorder" is a gross oversimplification of the 2nd law of Thermo. The law was written to intend to describe how differences in properties of gasses tend to even out over time, as the particles mixed and heat is shared. "Order" in the context of gasses might mean all the hot gas on the left side of a tank, and all the cold gas on the right side, and "disorder" would mean they're all mixed up, even though the gasses are of a uniform temperature once it's done. So even in that case "uniform" /= "order."

So, like, if someone drops a really dense fart, the 2nd law says sooner or later it'll make its way around the room.

Here's a better explanation:

http://en.wikipedia.org/wiki/Second_law_of_thermodynamics


Pop scientists like Hawking and Sagan confuse the issue with their analogies, sometimes, by drawing comparisons to how a "vase might fall off a table and break, but bits and pieces of a vase don't hop off the floor and reform themselves on the table," but really all they're doing when they say stuff like that is confusing the issue, because the 2nd law is supposed to apply to larger systems, and it becomes more "right" the larger the system you look at.

You're confusing randomness in situation with randomness in properties.

Because systems develop more entropy does not alter fundamental underpinnings of the universe.

The 2nd law says that in a closed evironment, the system will move towards entropy. What you're doing is misunderstanding what entropy means. It literally means more of a "evening out", the spread of energies becoming uniform.

For instance if I take a very hot rock, and a very very cold rock, drop them in a perfectly, 100% sealed and insulated container, and seal it, the hot rock wont stay hot, and the cold rock won't stay cold. The energy will "spread out" through the sytem, and, provided there is no external source of new energy, reach a uniform "spread outness". The measure of how spread out it is is the measure of its entropy.

The idea that the 2nd law means "things become more chaotic over time" is really not a very accurate explanation.

If that's the case then, could it be said that such things as the speed of light, or even the speed of time itself, were once a lot faster (or, I suppose, perhaps slower) than they are now, and at present, have apparently reached an equilibrium? Just wondering.

If that's the case then, could it be said that such things as the speed of light, or even the speed of time itself, were once a lot faster (or, I suppose, perhaps slower) than they are now, and at present, have apparently reached an equilibrium? Just wondering.

No, because those are not energy systems. The law states that ENERGY will distribute over time to reach an equilibrium.

Things like lightspeed aren't energy systems. They aren't a THING at all. It is a physical constant based on the properties of the universe. Those properties do not change based on how energy is spread out.

I look at it the other way than the previous posters. I think everything does tend towards chaos. At least, that agrees with all my observations, even evolution.

But also, even the 2nd law is not universal, as evolution also shows us that systems can tend towards more order and complexity.

I think the entire universe is tending towards chaos, though local manifestations of increasing order can be observed. I do not believe in any universal laws or constants, though. You don't have to hail Discordia; we are all living it.

I have two goldfish.

No, because those are not energy systems. The law states that ENERGY will distribute over time to reach an equilibrium.

Things like lightspeed aren't energy systems. They aren't a THING at all. It is a physical constant based on the properties of the universe. Those properties do not change based on how energy is spread out.

But those properties could. I realise my arguments boils down to me saying 'everything is possible' over and over again, but I have yet to find a rule where there is no exception, and if I can't, I assume that we will find one in the future. I am rarely disappointed.

I look at it the other way than the previous posters. I think everything does tend towards chaos. At least, that agrees with all my observations, even evolution.

Perhaps, but that's more an argument for chaos theory, not the 2nd law of thermodynamics. Whether that's true or not, that's not what the 2nd law states.

But also, even the 2nd law is not universal, as evolution also shows us that systems can tend towards more order and complexity.

But it's the second law of thermo... not the second law of evolution.

But those properties could. I realise my arguments boils down to me saying 'everything is possible' over and over again, but I have yet to find a rule where there is no exception, and if I can't, I assume that we will find one in the future. I am rarely disappointed.

Could the properties of the universe change in such a way that the speed of light would change? Well...sure, ok.

Yeah the fundamental underpinnings of physical laws could be torqued in such a way to alter the rules, at least in a local area.

That, however, has nothing to do with the 2nd law of thermodynamics.

But also, even the 2nd law is not universal, as evolution also shows us that systems can tend towards more order and complexity.

Entropy can fall in a part of the system, just so long as the net entropy rises.

If order tends towards disorder, how is it that anything LIKE a physical "law" exists in the universe as a constant?
Well, I put it to you that we actually don't know to what extent physical "laws" really do exist as a physical property of the universe. Are they a constant, wired into the fabric of existence as defined at the onset of the universe? Are they local, defined as a result of some internal property of each item of matter? Are they themselves items in some dimensional plane that can be altered with the right force?

These questions are, however, outside of the realm of science, because there are no known means of testing them. All we can do is observe and model.

Entropy can fall in a part of the system, just so long as the net entropy rises.

actually the 2nd law states that entropy will, over time, reach equilibrium.

Again, don't confuse entropy with disorder. Two different things.

I kind of view it like a musical instrument; if you play it long enough, with time it'll get out of tune ever so slightly, and then slightly more, and then slightly more...until the notes are completely different from what they were before. If the universe is tending towards chaos, couldn't that be the case for properties (such as speed) of light and time?

And yes, I know that my simple analogies are nothing to base scientific research off of; again I'm just wondering.

If that's the case then, could it be said that such things as the speed of light, or even the speed of time itself, were once a lot faster (or, I suppose, perhaps slower) than they are now, and at present, have apparently reached an equilibrium? Just wondering.

That'd screw with E=mc^2, and then the nuclear reaction which takes place stars in stars would be screwed with, and then we'd all be screwed.

I think. :confused:

I have two goldfish.

Given sufficient time the atoms of those goldfish will become randomly, but statistically uniformly, distributed throughout your place of dwelling.

If the universe is tending towards chaos, couldn't that be the case for properties (such as speed) of light and time?

That. Is not. What the second law. Means.

Again, remove from yourself the notion that the 2nd law means "things will get more chaotic over time". That's a gross oversimplification. It doesn't mean that.

What you are describing is possible. As noted, since we dont yet know if universal rules truly are universal, and what cuases them, it is possible to alter them, we just don't know how. Likewise they could be altering naturally.

The 2nd law however doesn't have anything what so ever to do with that. It only states that energy in closed systems will move towards equilibrium over time. That's it.

actually the 2nd law states that entropy will, over time, reach equilibrium.

Again, don't confuse entropy with disorder. Two different things.

Ah, ok. This only hightlights my need to start revising :D

Entropy can fall in a part of the system, just so long as the net entropy rises.

Given that the long term rise in entropy is based on random events, it is possible for entropy to actually decrease throughout a system. It is statistically implausible that all the oxygen molecules in my room* will move to form a layer just below the ceiling, causing me to suffocate, but it is possible.


* Not that my room is a closed system, but that is irrelevant here.

That. Is not. What the second law. Means.

Again, remove from yourself the notion that the 2nd law means "things will get more chaotic over time". That's a gross oversimplification. It doesn't mean that.

What you are describing is possible. As noted, since we dont yet know if universal rules truly are universal, and what cuases them, it is possible to alter them, we just don't know how. Likewise they could be altering naturally.

The 2nd law however doesn't have anything what so ever to do with that. It only states that energy in closed systems will move towards equilibrium over time. That's it.

Nononono. That last post of mine had nothing to do with the first; I tend to think, and post, out loud, as well as follow a lot of rabbit trails. I didn't mean that last comment in the context of the 2nd law of thermo - apologies for not clarifying.

Given sufficient time the atoms of those goldfish will become randomly, but statistically uniformly, distributed throughout your place of dwelling.
Given sufficient time its place of dwelling will itself be dispersed, so it won't necessarily be the case that the fish's distribution will be throughout the dwelling place. The problem is one of enclosure.

And you know, now that I think about it, it COULD be that the speed of light IS slowing down; but if the speed of time is slowing down at the same rate, we wouldn't notice any change in the speed of light...to us it would still seem to be moving at the same pace it always did. Just a thought.

Given that the long term rise in entropy is based on random events, it is possible for entropy to actually decrease throughout a system. It is statistically implausible that all the oxygen molecules in my room* will move to form a layer just below the ceiling, causing me to suffocate, but it is possible.


* Not that my room is a closed system, but that is irrelevant here.

So there's a chance - a really really really really remote one, that all my teeth will move out of my gums and do a little dance in the air?

Given that the long term rise in entropy is based on random events, it is possible for entropy to actually decrease throughout a system. It is statistically implausible that all the oxygen molecules in my room* will move to form a layer just below the ceiling, causing me to suffocate, but it is possible.


* Not that my room is a closed system, but that is irrelevant here.

Ignoring the closed system problem, as you pointed out, yes, entropy is about averages. Systems tend towards entropy, over time, such that, given an infinite amount of time, all things reach equilibrium, and the universe remains still and cold, forever.

But again, that is a tendancy, not a hard and fast absolute in any given timeframe.

Given sufficient time the atoms of those goldfish will become randomly, but statistically uniformly, distributed throughout your place of dwelling.

Given sufficient time its place of dwelling will itself be dispersed, so it won't necessarily be the case that the fish's distribution will be throughout the dwelling place. The problem is one of enclosure.

But I like my goldfish. :(

Perhaps, but that's more an argument for chaos theory, not the 2nd law of thermodynamics. Whether that's true or not, that's not what the 2nd law states.

I am aware of the second law of thermodynamics, but I took a quick look at wiki to refresh my memory. You are correct in the definition, but since the law is considered more true as the system observed gets larger, one can assume that the entire univers has an increasing entropy, and is therefore tending towards equilibrium. If you define entropy as chaos, then the universe is tending towards chaos. EDIT: After rereading the wiki article and thinking, I realise what meant to say was this: one can assume that the entire universe is a closed sytem, and is therefore tending towards equilibrium. If you define equilibrium as chaos, then the universe is tending towards chaos.

But it's the second law of thermo... not the second law of evolution.

Yes. But evolution is an example of a system that is tending towards order. Evolution, of course, has almost nothing to do with thermodynamics. I would argue, however that the amount of entropy created by billions of generations of millions of species all fucking, fighting, and feeding probably created more thermodynamic entropy than any apparent order caused by evolution, though it is still apples and oranges.

Could the properties of the universe change in such a way that the speed of light would change? Well...sure, ok.

Yeah the fundamental underpinnings of physical laws could be torqued in such a way to alter the rules, at least in a local area.

That, however, has nothing to do with the 2nd law of thermodynamics.

I think that the speed of light could be observed to be something other than C in a vacuum without changing the physical properties of the universe. We know that its velocity changes when exposed to the gravitational field of large masses, so the speed may also change.

Again, you are correct that it is not the 2nd law of thermodynamics. Just extending the idea to its logical extreme.

Entropy can fall in a part of the system, just so long as the net entropy rises.

This agrees with what I have observed.

And you know, now that I think about it, it COULD be that the speed of light IS slowing down; but if the speed of time is slowing down at the same rate, we wouldn't notice any change in the speed of light...to us it would still seem to be moving at the same pace it always did. Just a thought.

With respect to what is the speed of time slowing down? Time2? Does Time2 also slow down wrt Time3? Does Time3 also slow down wrt Time4?... yadda yadda...

Systems tend towards entropy, over time, such that, given an infinite amount of time, all things reach equilibrium, and the universe remains still and cold, forever.

...of course in a uniform distribution the word 'cold' loses all meaning.

With respect to what is the speed of time slowing down? Time2? Does Time2 also slow down wrt Time3? Does Time3 also slow down wrt Time4?... yadda yadda...

See? Now think about how much fun you'd have if you pondered that while you were high, and you'll see why the hippies were always such a happy bunch. :D

...of course in a uniform distribution the word 'cold' loses all meaning.

...well ok, fair enough.

Still and a few degrees above absolute zero sound better?

One wonders how one arrives at constants in the first place.

Dimensionless constants are not always "dimensionless".

Take Planck's constant, for example.

To address the question of whether the Planck length is a constant, you need two ingredients: (1) a way to measure the Planck length in different parts of the universe and (2) a reference length that can be assumed to be the same everywhere and everywhen. However, satisfying both these requirements is not as easy as it might seem at first, mostly because you have to avoid circular definitions. And you still need to make some kind of assumption in part (2).

I feel like the second law is a bit dodgy - more like a general observation than a concrete law. I'd like to drop it altogether from physics.

Its not dodgy, but it is a known law of the universe.

Alright, as we're on Thermodynamics(Which I am horribly confused by), can someone explain to me this:

As Thermodynamics APPEARS to be explaining the nature of energy, what is the argument that it somehow "disproves" evolution, and how the hell does it have anything to do with that?

The reason why I ask is not necessarily a full-blown tangent, just wondering exactly how far the theory goes, and what it pertains to in it's entirety.

If that's the case then, could it be said that such things as the speed of light, or even the speed of time itself, were once a lot faster (or, I suppose, perhaps slower) than they are now, and at present, have apparently reached an equilibrium? Just wondering.

Actually, Special Relativity states that time does slow down and speed up, to make sure the speed of light remains constant to anyone who measures it.

http://en.wikipedia.org/wiki/Special_relativity

Alright, as we're on Thermodynamics(Which I am horribly confused by), can someone explain to me this:

As Thermodynamics APPEARS to be explaining the nature of energy, what is the argument that it somehow "disproves" evolution, and how the hell does it have anything to do with that?

The reason why I ask is not necessarily a full-blown tangent, just wondering exactly how far the theory goes, and what it pertains to in it's entirety.

Here is a good link for the creationist stance on the second law of thermodynamics:

http://www.answersingenesis.org/docs/370.asp

Here is a good link for the creationist stance on the second law of thermodynamics:

http://www.answersingenesis.org/docs/370.asp

Ah. So it's basically that people don't understand the Second Law and what it describes.

Gotchya.

And you know, now that I think about it, it COULD be that the speed of light IS slowing down; but if the speed of time is slowing down at the same rate, we wouldn't notice any change in the speed of light...to us it would still seem to be moving at the same pace it always did. Just a thought.

Considering that speed is a measure kinda dependant on time, I don't think you can really say it slowed down in that case.

actually the 2nd law states that entropy will, over time, reach equilibrium.

Again, don't confuse entropy with disorder. Two different things.

Err. doesn't entropy reach a maximum, at equilibrium?

Another question that's debatable is whether or not the universe itself is a closed system or not.

Considering that speed is a measure kinda dependant on time, I don't think you can really say it slowed down in that case.

What I meant by that:

If time itself slows so that what we know as a second is twice as long as it normally is, that would make an hour twice as long as what we would normally say it is.

If a truck goes a constant speed, and time were twice as slow, it would in essence travel twice as far as it usually would in normal time, because in this nistance time is moving at half speed.

The reverse is seen in everyday application: if time remains constant and you halve the speed of something, it's only going to go half as far in a given amount of time.

To summarize, what I'm saying is that if the speed of time changed at the same rate as the speed of light, then no noticable changes in either's speed would be noticed.

Considering that speed is a measure kinda dependant on time, I don't think you can really say it slowed down in that case.Quick observation there, but not entirely correct. There's no universal reference point with set properties, so if the speed of light was slowing down, it'd eventually be possible to detect it.Err. doesn't entropy reach a maximum, at equilibrium?There is no real equilibrium (other than perhaps non-existence), so no. In terms of the universe, it means the universe will cease to exist in any sense we'd recognise, given enough time. And if memory serves, 'enough time' is about half a googol years.Another question that's debatable is whether or not the universe itself is a closed system or not.True. And of course, it has to be a closed system for the above to be correct. There is, however, nothing to suggest it isn't a closed system. To summarize, what I'm saying is that if the speed of time changed at the same rate as the speed of light, then no noticable changes in either's speed would be noticed.That's a pretty important clarification. It just isn't applicable to our universe. Time, disconnected from any other universal properties, is strictly a product of causality. Lightspeed has no bearing on our perception of time - though what you describe would have a rather massive effect on the survivability of our species.

But it's the second law of thermo... not the second law of evolution.

To be fair, it's the second law of statistical mechanics, of which thermo is a large part.