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Questions about entropy, normal force, and the human body

  1. Jan 4, 2014 #1
    Greetings folks,
    I'm new to this forum and to physics in general so apologies if I come off like a greenhorn or if I am posting these questions in the wrong place. I have an Arts background and have never really "gotten" science, but my interest in post-Enlightenment philosophy has led me to a fascination with quantum physics and the potential challenges that it poses to rationalism. My initial question is this: can the human body convert normal force into usable energy? In other words, does the simple act of standing on a spatial surface (be it the ground, a floor, a sidewalk, etc) involve an exchange of energy that the body can store and use at a later time? If so, how does the exchange take place, what types of energy does it involve, and is it one-sided or does it work both ways - i.e. does the Earth also absorb energy from my body that it can use to feed other natural processes? Also, do you think it is possible to reconcile the theory of entropy as energy dispersal with that of entropy as a measure chaos within a closed system? For instance, could my standing in a particular place either divert energy from or redirect energy to a weather system that would, in turn, either increase or decrease the likelihood that it would rain somewhere else? Please excuse me if these sound like the half-baked theories of an ill-informed layperson but I ask out of pure curiousity.

  2. jcsd
  3. Jan 4, 2014 #2


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    Staff: Mentor

    No. Consider that if you stand long enough, you start to get tired - your muscles are turning the food you've eaten into energy just to keep you standing there.

    Again, no. You'll see the pop-sci press try explain entropy as "chaos", "disorder", "energy dispersal", and the like, but that's because they're trying to explain a fairly abstract (but rigorously defined) mathematical concept without using math. It gives you a sort-of OK hand-waving sense of what entropy is about, but not a foundation that you can develop new ideas from.

    If you're really interested in this stuff, it's worth unlearning the pop-sci glossy overview and starting over with a more serious study. It's a lot of work, but it's also the difference between reading a restaurant review and eating at the restaurant yourself.
    Last edited: Jan 4, 2014
  4. Jan 4, 2014 #3
    Okay, cool. Well, that's certainly a start. Can you suggest an introductory reading list and/or a few links that might subvert my popularly-received but erroneous understanding of entropy in at least a semi-comprehensible fashion?
    Last edited: Jan 4, 2014
  5. Jan 5, 2014 #4


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    Gold Member

    Susskind touches a bit on the relationship between chaos and entropy in his lecture. It's not as direct as you propose, but it helps explain the lack of reversibility. Here's a summary:

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