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Battling Entropy

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Re: Battling Entropy

#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 getting dangerously close to the kind of pseudoscientific platitudes that ended up making something like this marketing description of the Pepsi logo, which "uses" general relativity in its description: https://www.goldennumber.net/wp-content/uploads/pepsi-arnell...

Re: Battling Entropy

#3

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…

    The Pepsi Orbits
    Dimensionalize 
    exponentially.
The most profound thing you’ll read today! (The last diagram is a bit disappointing, though.)

Re: Battling Entropy

#4

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.

Re: Battling Entropy

#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 as nature’s tax[2].

I don't understand this. Please note that I've never had any physics training so I'd love for someone with a more formal physics education to help me out here. 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?

The fact that stars are forming together and creating heat -- that -- is the disorder in my eyes. We are all disturbances in the energy of the universe. I would call a perfectly uniformly smoothed out heat-death of the universe perfect order (i.e. the opposite of chaos).

Or am I completely wrong here?

Re: Battling Entropy

#7

>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…

You're making the (very common) mistake of taking a poetic English-language interpretation of a physical law -- which is necessarily lossy/imprecise, since the actual law is mathematical -- and over-interpreting the words without referring back to the actual law.

You can see the law (in the context of thermal & statistical physics) at https://en.wikipedia.org/wiki/Entropy_(statistical_thermodyn.... You can of course argue that 'disorder' isn't a good way of translating the maths into English, but shrug, it's the one people seem to have settled on. And of course, that's orthogonal to whether the actual law is true or not.

Re: Battling Entropy

#8
Entropy has been increasing since the big bang, when it was at minimum value. While the total energy didn't change since then, there has been a vast increase in the potential locations of that energy and a vast increase in the number of different interactions possible within that energy. This increases entropy because the possibility space has increased.

Boltzman entropy is defined as the number of potential microscopic possibilities that could equivalently produce the measurable macrostate which is observed. (No wonder people just call entropy disorder -- it's complicated). So, the entropy of a glass of water consists of all the possible combinations of position and momentum that all the water molecules could be in. When the water is frozen, the possibility space is smaller than when the water is hot.

https://en.m.wikipedia.org/wiki/Entropy

How does this relate to order? I think of this in terms of the likelihood of a random transformation of the system to affect it's functional interaction with other systems. So, let's say you randomly transform the position or momentum of a part of a house, it is likely change functional interactions of people in that house. However, when the same material in the house is just sitting in a pile of rubble, it has more entropy because a random transformation of the rubble won't really affect the function of the rubble -- it is still, for all intents and purposes, the same pile of rubble (even though it would take just as many bits of information to describe with precision).

I'm not a physicist, but a humanist who thinks it is important to understand physics. So open to correction here.

Re: Battling Entropy

#9

>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…

It always confuses me as well (and I have at least some Physics background, having done a year as an undergrad). I think this is because I confuse it with the statistical measure of the entropy of a distribution, where a uniform distribution will maximise entropy.

Re: Battling Entropy

#10

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…

Interestingly, biological beings seems to defy the second law by working to reduce disorder, or surprises, in the sensory system. This is the meat of Karl Friston's Bayesian hypothesis of the brain.
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