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Battling Entropy

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Re: Battling Entropy

#31

Post by kgwgk »

eru wrote: post #28
kgwgk wrote: post #18

Earlier quoted context omitted.

Thermodynamical entropy is not a physical property of a system. It’s a property of our description of the system as a macroscopic state. Quantum (von Neumann) entropy is a related but different concept. It’s worth noting that it is constant for a closed system. Cosmological entropy can be defined in different ways. In summary, entropy means many things and not all “entropies” behave in the same way.

Interesting enough, even though entropy is in some sense a property of a description of a system, there are things like 'entropic forces' and they play a big role in physics. https://en.wikipedia.org/wiki/Entropic_force

Entropic forces are not more real than centrifugal forces or the Coriolis force. They appear when we use a thermodynamic description of a system.

That wikipedia page doesn’t make much sense, but note that the “mathematical formulation” is about macrostates and canonical ensembles.

See also https://johncarlosbaez.wordpress.com/2012/02/01/entropic-for...

Re: Battling Entropy

#32

Post by lovemenot »

Rainymood wrote: post #6

>The second law of thermodynamics states that “as one goes forward in time, the net entropy (degree of disorder) of any isolated or closed system will always increase (or at least stay the same).”[1] That is a long way of saying that all things tend towards disorder. This is one of the basic laws of the universe and is something we can observe in our lives. Entropy is simply a measure of disorder. You can think of it…

>> a perfectly uniformly distributed of zero temperature mass ... is the perfect order

At max entropy, things would not be uniformly distributed: equal distance between each atom. Rather they would be randomly distributed. There'd be some clumping but without much pattern. If such a system were of near infinte size, the number of variations of its alignments would far exceed the much smaller near-infinity of slightly or somewhat more ordered possible systems in the same universe. Especially in the case of your uniformly ordered one, which is almost unique in that universe.

Re: Battling Entropy

#33

Post by [deleted] »

ebullientocelot wrote: post #23
db1 wrote: post #4

Earlier quoted context omitted.

Oh my god that pepsi document. It's real? Was someone actually paid to produce that document? As I scrolled downwards I just kept getting more and more convinced that it's some kind of ridiculous surrealistic joke thing.

I know, right?? Some real gems: pg. 21: Emotive forces shape the gestalt of the brand identity. Actually no, the whole thing is patently absurd. Wow. What the fuck? Apparently this presentation earned a million dollar fee: https://www.cbsnews.com/news/pepsis-nonsensical-logo-redesig... In fairness it is marked as WIP.. I suppose it could have been completely scrapped and redone before presenting to the client :P Edit…

[deleted]

Re: Battling Entropy

#34

Post by sosuke »

db1 wrote: post #4
saagarjha wrote: post #2

This article begins with an analogy to the thermodynamic concept of entropy, and then attempts to relate it to other kinds of "entropy" by making the simplification that entropy is equivalent to disorder. That's all fine and well, but then I really thinks it goes too far: you really can't try to "reduce entropy" in your business by looking at a physical process, nor is coughing "the transfer of energy as heat". It's…

Oh my god that pepsi document. It's real? Was someone actually paid to produce that document? As I scrolled downwards I just kept getting more and more convinced that it's some kind of ridiculous surrealistic joke thing.

The Pepsi doc is real https://www.cbsnews.com/news/pepsis-nonsensical-logo-redesig...

Re: Battling Entropy

#35

Post by coldtea »

ebullientocelot wrote: post #23
db1 wrote: post #4

Earlier quoted context omitted.

Oh my god that pepsi document. It's real? Was someone actually paid to produce that document? As I scrolled downwards I just kept getting more and more convinced that it's some kind of ridiculous surrealistic joke thing.

I know, right?? Some real gems: pg. 21: Emotive forces shape the gestalt of the brand identity. Actually no, the whole thing is patently absurd. Wow. What the fuck? Apparently this presentation earned a million dollar fee: https://www.cbsnews.com/news/pepsis-nonsensical-logo-redesig... In fairness it is marked as WIP.. I suppose it could have been completely scrapped and redone before presenting to the client :P Edit…

>pg. 21: Emotive forces shape the gestalt of the brand identity.

Which is trivially true.

Forces of emotion (how consumers feel about the brand) is what shapes brand identity.

Gestalt here means something greater than the sum of its parts, which brand identity is -- what we perceive as a "brand" is not a single thing but tons of them (the logo, the product line, their retail shops, the ads, our past experiences with their products, the cultural significance of the brand, and so on).

Re: Battling Entropy

#36

Post by coldtea »

Rainymood wrote: post #6

>The second law of thermodynamics states that “as one goes forward in time, the net entropy (degree of disorder) of any isolated or closed system will always increase (or at least stay the same).”[1] That is a long way of saying that all things tend towards disorder. This is one of the basic laws of the universe and is something we can observe in our lives. Entropy is simply a measure of disorder. You can think of it…

>Why is this a measure of "disorder"? In my eyes, a perfectly uniformly distributed of zero temperature mass (or maybe absolute zero, not sure) of grey energy is the perfect order?

Order here means something specific.

A sand castle has more order, in that sense, than sand thrown around (e.g. the default state of sand in a beach) -- the sand in the castle is ordered in specific ways to represent something.

>I would call a perfectly uniformly smoothed out heat-death of the universe perfect order (i.e. the opposite of chaos).

Again, chaos in this sense means (to put it in layman terms) that nothing is put in some particular order. The "perfectly uniformly smoothed out heat-death of the universe" means nothing is explicitly ordered in some way -- any chunk of that universe that you take will have an equal distribution.

Here's another example:

A layered cake has an order (e.g. chocolate, cream, biscuit, marmelade, biscuit).

A layered cake mixed up on the blender on high, has no such order, it's all a chaos (even though it's smoother).

Re: Battling Entropy

#37

Post by crimsonalucard »

lovemenot wrote: post #32
Rainymood wrote: post #6

>The second law of thermodynamics states that “as one goes forward in time, the net entropy (degree of disorder) of any isolated or closed system will always increase (or at least stay the same).”[1] That is a long way of saying that all things tend towards disorder. This is one of the basic laws of the universe and is something we can observe in our lives. Entropy is simply a measure of disorder. You can think of it…

>> a perfectly uniformly distributed of zero temperature mass ... is the perfect order At max entropy, things would not be uniformly distributed: equal distance between each atom. Rather they would be randomly distributed. There'd be some clumping but without much pattern. If such a system were of near infinte size, the number of variations of its alignments would far exceed the much smaller near-infinity of slightly…

This is entirely incorrect. Our solar system started out as a gas cloud of randomly distributed atoms which then proceeded to become atoms organized into spheres called planets. This happened spontaneously and is not the result of energy entering or exiting the system.

Almost all atoms started out in a state of random distribution before transforming themselves into almost perfect spheres orbiting in an almost perfectly circular orbit around a giant glowing sphere called a star. These stars then organize themselves into beautiful ordered spirals called galaxies. Entropy always increases and most people think high entropy is a state of random distribution, but the organization of atoms in the universe is definitely not heading in that direction.

Thanks to gravity the universe will not become a place where atoms are perfectly randomly distributed. This does not make sense from an intuitive perspective and observational as well.

Strange right? Entropy has not reversed. What's going on most people don't have an intuitive grasp of what the true definition of entropy is.

Allow me to elucidate.

The "disorder" that entropy refers to can actually take on many forms. In the case of our solar system it is perfect spheres that orbit another glowing perfect sphere. In the case of food coloring dispersing in a glass it is atoms randomly distributed.

Entropy simply put should not be called a law it is really a consequence of probability. If the organization of atoms is in a high probability state than it has high entropy if it is in a low probability state than it has low entropy. Put it this way: atoms and gravity by probability are more likely clump into perfect spheres rather than stay in a perfectly randomly distributed gaseous state. Spherical planets are then according to this definition entropy, at a higher state of entropy than a gas dust cloud.

Seem crazy right? It seems like entropy is reversing... randomly distributed atoms organizing themselves into clumps of perfect spheres... The reality is nothing crazy is going on. Intuitively we know gas dust clouds organize them selves into spherical planets and solar systems. It's your definition of entropy that is off. Are intuitive notions of disorder and chaos are clashing with what entropy defines as 'disorder' and 'chaos'

Re: Battling Entropy

#38

Post by crimsonalucard »

People think that entropy increasing is basically atoms going from a state of organization to a state of random distribution.

All you need to do is look at the universe to see how off this definition is.

The universe started as a big bang: a soup of randomly distributed particles.

Then the atoms proceeded to self organize into perfect spheres called planets and stars which in turn organized themselves into flat ordered spiral structures called galaxies.

If entropy is increasing always how does this happen? It happens because your understanding of entropy is off.

Re: Battling Entropy

#39

Post by dougk16 »

crimsonalucard wrote: post #38

People think that entropy increasing is basically atoms going from a state of organization to a state of random distribution. All you need to do is look at the universe to see how off this definition is. The universe started as a big bang: a soup of randomly distributed particles. Then the atoms proceeded to self organize into perfect spheres called planets and stars which in turn organized themselves into flat order…

I've always considered the "increasing disorder" definition of entropy to be a simple analogy that most people can relate to in their everyday lives, not necessarily a formal definition. Indeed I would be interested to know if you can even formally define order vs. disorder since it seems to require a subjective observer. For example the universe doesn't consider a glass sitting on the table to be "more ordered" than one that has shattered on the floor. It's just like, our opinion man.

But even if you use the order vs. disorder analogy, it's arguable that the universe was close to perfectly ordered right after the big bang. After all it was a pretty smooth and uniform distribution of matter/energy at some point, and that seems more ordered to me than what we have now with all these random clumps of star junk everywhere :)

Anyway I like to consider entropy as the amount of usable energy in a system. A whole glass has more energy to release (e.g. by shattering) than a shattered one does. Maybe this is the formal definition of order vs. disorder?

Re: Battling Entropy

#40

Post by stevedekorte »

" Too little autonomy for employees results in disinterest, while too much leads to poor decisions."

The author appears to confuse autonomy with a lack of feedback mechanisms. Economies are based on a vast number of autonomous agents (independent organizations) who are selected for survival via market feedback (prices) and the long term trend in these has been towards ever greater agent granularity (vertical disintegration).

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