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Re: 2nd law of thermodynamics

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  • boblerwill
    Thanks for this Leo, I would be interested to see the Infinite Energy article, but I have never heard of the magazine and do not know how to get hold of it. Is
    Message 1 of 8 , Jul 1, 2002
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      Thanks for this Leo,

      I would be interested to see the Infinite Energy article, but I have
      never heard of the magazine and do not know how to get hold of it. Is
      this a magazine that is only available in the US? In my experience,
      anyone who thinks they have aan analogue of Maxwell's Demon probably
      doesn't; but I live in hope.

      I did see the Unidirectional heat flow article: in fact I bought the
      paper. Unfortunately, interesting though the idea is, it turned out
      it had no application to violating the 2nd law. The phenomenon they
      described was a bulk phenomenon. Heat would flow in one direction
      faster than the other direction, but only when the bulk temperature
      difference was in the driving direction of the heat flow. The
      material would not respond to the microscopic differences in energy
      of individual molecules. From what I could see about the mechanism,
      it could not be adapted. I shall send you the paper if you are
      interested.

      I am interested in the notion of a molecular engineered one-way heat
      trap. Such a device would have to be leaky because it would have to
      be small enough to respond to individual molecule energy, and so
      could not be large enough to be completely unidirectional. I deal
      with this question in a later part of the series of postings of which
      what I posted Saturday is the first.

      Once again, thanks for your interest. I expect you are at least as
      far along this line of thinking as myself.

      Bob Lerwill

      --- In AMBIENTENERGY@y..., "chudslayer" <BordersChess@h...> wrote:
      > Bob,
      >
      > The latest edition of the pro-FE magazine "Infinite Energy"
      contains
      > a proposal for a Maxwell's demon type device based on osmosis using
      a
      > membrane with covalently tethered solute molecules on one side (let
      > me know if you want more detail). The article also suggests other
      > related 2nd Law violaters. Normally I do not have a very high
      > opinion of the magazine, but this article caught my eye since I
      have
      > been contemplating such approaches to achieving an asymmetric
      > molecular process. I think the author of the article overlooked
      some
      > important factors, but like you, I believe that these approaches
      are
      > worth considering.
      >
      > On a slightly different track, do you recall that a few months ago
      > researchers anounced that a material whic allows heat flow in only
      > one direction is theoretically possible? (I can look up the URL if
      > anyone wants it) They did not suggest that it could be used to
      > create temperature differences from ambient heat, but rather that
      it
      > might be a useful insulating material (think of a thermos bottle
      that
      > can be heated on a stove, but then safely retains its internal heat
      > on the bus ride to work). I was wondering if this idea (based on
      > sandwiching of materials acting as symmetric and asymmetric
      > oscillatiors) could be applied at the molecular level in the form
      of
      > a synthetic protein/RNA/polymer which coud perform as a Maxwell's
      > demon. Any thoughts on this approach?
      >
      > Leo C.
      >
      >
      > --- In AMBIENTENERGY@y..., "Robert Lerwill" <bob.mo@v...> wrote:
      > > I would very much like to see someone engineer a device that
      > converted ambient heat into useful work. I think know broadly how
      it
      > could be done, but there is a phenomenon that needs to be found to
      > allow it to happen. It may be that the phenomenon is already known
      > about, but its significance has been missed. I hope by spreading my
      > ideas, one of you may realise that something they already know
      about
      > has the required properties and will take the idea forward.
      > >
      > > I posted a similar message to what follows some time ago, but had
      > no response. The message below is the first in a series I have
      posted
      > to another group. I did not post it to this group before for fear
      it
      > would offend the sensibilities of Mr Cantrell. Some respect is owed
      > him since he founded the group in the first place and devotes
      > considerable energy to the same thing I want to achieve, even if in
      > my opinion he is regrettably going in the wrong direction. Now it
      > seems he has left the group and in any case has taken offence at
      > anything I do or say, I am posting it here regardless. I hope you
      > find it of interest.
      > >
      > >
      > > The 2nd law of thermodynamics was what got me interested in
      Physics
      > in the first place. My school teachers, and later my University
      > lecturers could not answer the questions I had. I had to go out and
      > get those answers myself. Some of you may be interested.
      > >
      > > To flip through to the end, I believe that it is theoretically
      > possible to violate the 2nd law and generate useful work out of
      heat
      > at ambient temperature. (Whether or not it is practical I am
      hesitant
      > to claim. I have some schemes, but they may be flawed). Now you may
      > tell me that this is nonsense, that the 2nd law is one of the best
      > authenticated and most reliable laws in Physics, but to that I
      would
      > say that that is because very few people are seriously questioning
      > it. It is considered a dead subject at University level. (When I
      had
      > some searching questions on its validity, I was told that I would
      be
      > better off digging out retired physicists than current ones.)
      > Relativity, on the other hand, is constantly poured over in the
      hope
      > that a flaw will be found. On those grounds alone, I have much more
      > trust in Relativity than I do in something like the 2nd law which
      is
      > at least twice as old. New discoveries in Physics are constantly
      > being made, but who is it that is checking the relevance to 200
      year
      > old laws?
      > >
      > > In what follows, there is some fairly fundamental but little
      > discussed concepts. if what follows is unfamiliar to you, I suggest
      > you take some time to digest it.
      > >
      > > To violate the 2nd law, what you would have to do is take the
      > random microscopic fluctuations in energy levels due to heat and
      > harness them into some macroscopic energy level difference. What
      got
      > me interested in the first place was that it is evident that this
      can
      > be done on a larger scale with suitable engineering. For example,
      > random motions of the wrist can cause the mainspring of an
      automatic
      > watch to be wound up. Why should this be impossible on the
      > microscopic scale using Brownian motion? If there is fundamentally
      > impossible, then searching for a mechanism would be a waste of
      time.
      > So the first question is:
      > >
      > > Is a violation of the 2nd law of thermodynamics possible in any
      > conceivable self-consistent Universe?
      > >
      > > The definition of the 2nd law I use is that of Boltzmann (I
      believe
      > it is inscribed on his tombstone): In any isolated system ds >= 0
      > where s = ln(w) and w (which I shall use for omega) is the number
      of
      > microstates that are consistent with one particular macrostate. To
      > avoid the possible objection that the distinction between
      macrostates
      > is subjective, I say that if it is possible to devise a practical
      > machine that can harness energy when one microstate changes to
      > another microstate, then the two microstates can be described by
      > different macrostates.
      > >
      > > The 2nd law is a statistical law. If we suppose that a system A
      has
      > a total number of microstates, wMax, and that the microstates are
      all
      > of equal probability (i.e equal energy), then each microstate will
      > have an even population over infinite time. However, typically, a
      > vast majority of those microstates will correspond to one single
      > macrostate. As a result, it will appear that the system will go to
      > that single macrostate, and the probability of any other macrostate
      > spontaneously coming into existence is so infinitesimal it is not
      > worth considering.
      > >
      > > As an example, consider an ideal gas in an enclosed volume. There
      > are a very large number of possible ways to distribute the
      molecules
      > around the volume. a much smaller number correspond to all of the
      > molecules being in one half of the volume. However there is no
      > difference in probability (there being no energy interactions
      between
      > the ideal gas molecules) between one microstate in which the
      > molecules are evenly distributed and one in which all are in one
      > half. It is purely the statistics which determine that the former
      > state is the one we almost inevitably see. If, however, all the
      > molecules did move into one half, it would be practical to erect a
      > barrier which would allow us to harness energy when the molecules
      > reverted to the almost infinitely more probable state of even
      > distribution. This means that half in one side comprises a
      different
      > macrostate.
      > >
      > > Now let us suppose we could erect a barrier between the two
      halves
      > (analogous to one populated by Maxwell's demons) which only allowed
      > passage in one direction. The molecules in the gas are in constant
      > motion. They will all come in contact with the barrier at one time.
      > If they do, they will pass through to the more populated half and
      be
      > denied passage back to the less populated half. The end result will
      > be the highly improbable state described above where all the
      > molecules are in one half of the volume. They could then be allowed
      > to expand into the empty half while doing useful work; the
      > temperature of the system would drop. Such a scenario is deemed
      > impossible by the 2nd law. To put it another way, if such a barrier
      > could exist, the 2nd law could be violated.
      > >
      > > When you try to engineer such a barrier, you soon find the
      problem.
      > (It does not matter if you try to engineer with a population
      > difference as described above or the more complex individual
      > potential energy difference as described by Maxwell when he
      > postulated his demon that could create a spontaneous temperature
      > difference). Such a membrane cannot be engineered easily. On the
      > microscopic level where such a mechanism would have to be
      engineered,
      > processes tend to be reversible. If the probability of the forward
      > process is exactly the same as the reversible process, then there
      is
      > no net flow across the barrier. We are used to mechanisms on the
      > macroscopic scale that can have a unidirectional preference. the
      > ratchet on an automatic watch is such a process. However such
      > mechanisms depend on their macroscopic nature to achieve this
      > irreversibility. The watch ratchet is unidirectional because when
      the
      > pawl descends into the ratchet, the excess energy is dissipated as
      > heat. On the microscopic level, there is no such thing as heat or
      > dissipation. the pawl descending into the ratchet will bounce back
      to
      > the same height as it descended from. the process is entirely
      > reversible. You might postulate some system of sprung trap-doors to
      > allow the molecules to flow in one direction, but such a system
      would
      > not work on the microscopic level because as soon as they closed,
      > they would bounce back open again.
      > >
      > > What is require is some process that is essentially asymmetric on
      > the microscopic level. The way this asymmetry is expressed is in
      > terms of time asymmetry. If you could film the interactions between
      > two particles, and then play the film backwards, would it be
      > possible, without any prior knowledge of which process was real and
      > which had been played backwards to say which film was of the real
      > event? I find it particularly ironic that the essential
      > irreversibility of events on the macroscopic level is a consequence
      > of the essential reversibility of processes on the microscopic
      level.
      > >
      > > to return to the original question. The answer is that a
      violation
      > of the 2nd law of thermodynamics is possible in a conceivable
      > universe, but only if that universe contains processes that are
      > irreversible on the microscopic level.
      > >
      > > the next question to be asked is do we live in such a Universe?
      > >
      > > ...To be continued.
      > >
      > > Bob Lerwill
    • kirk
      Evaporation is mostly a one way heat flow as long as the humidity is low. Kirk ... From: boblerwill [mailto:bob.mo@virgin.net] Sent: Monday, July 01, 2002
      Message 2 of 8 , Jul 1, 2002
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        Evaporation is mostly a "one way" heat flow as long as the humidity is low.

        Kirk

        -----Original Message-----
        From: boblerwill [mailto:bob.mo@...]
        Sent: Monday, July 01, 2002 3:22 AM
        To: AMBIENTENERGY@yahoogroups.com
        Subject: [AMBIENTENERGY] Re: 2nd law of thermodynamics


        Thanks for this Leo,

        I would be interested to see the Infinite Energy article, but I have
        never heard of the magazine and do not know how to get hold of it. Is
        this a magazine that is only available in the US? In my experience,
        anyone who thinks they have aan analogue of Maxwell's Demon probably
        doesn't; but I live in hope.

        I did see the Unidirectional heat flow article: in fact I bought the
        paper. Unfortunately, interesting though the idea is, it turned out
        it had no application to violating the 2nd law. The phenomenon they
        described was a bulk phenomenon. Heat would flow in one direction
        faster than the other direction, but only when the bulk temperature
        difference was in the driving direction of the heat flow. The
        material would not respond to the microscopic differences in energy
        of individual molecules. From what I could see about the mechanism,
        it could not be adapted. I shall send you the paper if you are
        interested.

        I am interested in the notion of a molecular engineered one-way heat
        trap. Such a device would have to be leaky because it would have to
        be small enough to respond to individual molecule energy, and so
        could not be large enough to be completely unidirectional. I deal
        with this question in a later part of the series of postings of which
        what I posted Saturday is the first.

        Once again, thanks for your interest. I expect you are at least as
        far along this line of thinking as myself.

        Bob Lerwill

        ---
        Outgoing mail is certified Virus Free.
        Checked by AVG anti-virus system (http://www.grisoft.com).
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      • boblerwill
        ... is low. ... True, but is not sustainable. As soon as the liquid has all evaporated or the air gets saturated, the evaporation will stop. It is easy to get
        Message 3 of 8 , Jul 1, 2002
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          --- In AMBIENTENERGY@y..., "kirk" <kirk@3...> wrote:
          > Evaporation is mostly a "one way" heat flow as long as the humidity
          is low.
          >

          True, but is not sustainable. As soon as the liquid has all
          evaporated or the air gets saturated, the evaporation will stop.

          It is easy to get a spontaneous temperature difference from a system
          that is not at equilibrium to start with and is heading towards
          equilibrium. After all, that is how the dipping bird works: but all
          you are doing is taking advantage of the lack of equilibrium and
          using it as the "power source".

          What is required to get large sustainable amounts of useful work from
          ambient heat is a system that generates a spontaneous temperature
          difference (or a spontaneous pressure difference) from a system *At
          Equilibrium*.

          This is spelt out in the definitions of the second law by saying the
          system operates "in a cycle" or by talking about the "sole change".
          Evaporating water can produce a spontaneous temperature differential,
          but if the water is not re-condensing back into the the original
          place, it is not operating in a sustainable cycle, the temperature
          difference is not the sole change. That is why the dipping bird is
          not violating the 2nd law when it extracts work from ambient heat.

          The device described in Boyd's "Text & Sketches" document would, if
          it worked, be violating the second law. This should be obvious from
          considering the fact that it would have to be able to create and
          maintain a temperature differential without any external changes
          taking place. (I should make it clear at this point that although I
          have always believed that violating the second law may be possible, I
          regrettably do not happen to think that this particular device will
          work)

          I am sorry if I seem to be laboring this point, but it seems to be
          behind some of the misunderstandings in this group.

          Bob Lerwill
        • chudslayer
          Bob, Thanks for your reply. I am encouraged to know that there are other knowledgable persons in the group who are interested in a molecular- scale heat-trap
          Message 4 of 8 , Jul 1, 2002
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            Bob,

            Thanks for your reply. I am encouraged to know that there are other
            knowledgable persons in the group who are interested in a molecular-
            scale heat-trap or Maxwell's demon approach.

            I'm not surprised that Infinite Energy magazine is unavailable
            outside of the US (low circulation). I will gladly mail to you a
            photocopy of the article that I mentioned in my previous post -- just
            send me a mailing address offline, or I could email it to you as a
            PDF file if I can manage to scan it (I will send copies to other
            interested members too, but I won't post digital copies since this
            might violate copyright).

            Thank you for offering to send the unidirectional heat flow article,
            but that won't be necesarry since I can get it from a local
            university library. You are correct about the bulk nature of the one-
            way heat flow, but I am looking into the idea of designing (on paper
            for now) a polymer whose individual molecules might be able to absorb
            and transfer kinetic energy to individual gas molecules. The polymer
            would contain regions of different chemical character (e.g., peptide-
            polyethylene-RNA) with different vibratory harmonics
            (stiff/lose/harmonic/anharmonic). These strands would traverse a
            very thin insulating barrier between two gas chambers. The energy
            absorbing and emitting ends of the polymer would protrude into their
            respective chambers, where fast and slow gas molecules, respectively,
            could collide with them. It's a stretch, but as a physical-organic
            chemist, I enjoy pondering such schemes.

            Any feedback that you (or anyone else) could provide on my scheme
            would be greatly appreciated. I look forward to the rest of your
            series of posts.

            Leo C.

            P.S. I don't mean to be secretive about my last name, but I have
            been receiving strange phone calls since posting critical replies on
            the free_energy group a few months ago.



            --- In AMBIENTENERGY@y..., "boblerwill" <bob.mo@v...> wrote:
            > Thanks for this Leo,
            >
            > I would be interested to see the Infinite Energy article, but I
            have
            > never heard of the magazine and do not know how to get hold of it.
            Is
            > this a magazine that is only available in the US? In my experience,
            > anyone who thinks they have aan analogue of Maxwell's Demon
            probably
            > doesn't; but I live in hope.
            >
            > I did see the Unidirectional heat flow article: in fact I bought
            the
            > paper. Unfortunately, interesting though the idea is, it turned out
            > it had no application to violating the 2nd law. The phenomenon they
            > described was a bulk phenomenon. Heat would flow in one direction
            > faster than the other direction, but only when the bulk temperature
            > difference was in the driving direction of the heat flow. The
            > material would not respond to the microscopic differences in energy
            > of individual molecules. From what I could see about the mechanism,
            > it could not be adapted. I shall send you the paper if you are
            > interested.
            >
            > I am interested in the notion of a molecular engineered one-way
            heat
            > trap. Such a device would have to be leaky because it would have to
            > be small enough to respond to individual molecule energy, and so
            > could not be large enough to be completely unidirectional. I deal
            > with this question in a later part of the series of postings of
            which
            > what I posted Saturday is the first.
            >
            > Once again, thanks for your interest. I expect you are at least as
            > far along this line of thinking as myself.
            >
            > Bob Lerwill
            >
            > --- In AMBIENTENERGY@y..., "chudslayer" <BordersChess@h...> wrote:
            > > Bob,
            > >
            > > The latest edition of the pro-FE magazine "Infinite Energy"
            > contains
            > > a proposal for a Maxwell's demon type device based on osmosis
            using
            > a
            > > membrane with covalently tethered solute molecules on one side
            (let
            > > me know if you want more detail). The article also suggests
            other
            > > related 2nd Law violaters. Normally I do not have a very high
            > > opinion of the magazine, but this article caught my eye since I
            > have
            > > been contemplating such approaches to achieving an asymmetric
            > > molecular process. I think the author of the article overlooked
            > some
            > > important factors, but like you, I believe that these approaches
            > are
            > > worth considering.
            > >
            > > On a slightly different track, do you recall that a few months
            ago
            > > researchers anounced that a material whic allows heat flow in
            only
            > > one direction is theoretically possible? (I can look up the URL
            if
            > > anyone wants it) They did not suggest that it could be used to
            > > create temperature differences from ambient heat, but rather that
            > it
            > > might be a useful insulating material (think of a thermos bottle
            > that
            > > can be heated on a stove, but then safely retains its internal
            heat
            > > on the bus ride to work). I was wondering if this idea (based on
            > > sandwiching of materials acting as symmetric and asymmetric
            > > oscillatiors) could be applied at the molecular level in the form
            > of
            > > a synthetic protein/RNA/polymer which coud perform as a Maxwell's
            > > demon. Any thoughts on this approach?
            > >
            > > Leo C.
            > >
            > >
            > > --- In AMBIENTENERGY@y..., "Robert Lerwill" <bob.mo@v...> wrote:
            > > > I would very much like to see someone engineer a device that
            > > converted ambient heat into useful work. I think know broadly
            how
            > it
            > > could be done, but there is a phenomenon that needs to be found
            to
            > > allow it to happen. It may be that the phenomenon is already
            known
            > > about, but its significance has been missed. I hope by spreading
            my
            > > ideas, one of you may realise that something they already know
            > about
            > > has the required properties and will take the idea forward.
            > > >
            > > > I posted a similar message to what follows some time ago, but
            had
            > > no response. The message below is the first in a series I have
            > posted
            > > to another group. I did not post it to this group before for fear
            > it
            > > would offend the sensibilities of Mr Cantrell. Some respect is
            owed
            > > him since he founded the group in the first place and devotes
            > > considerable energy to the same thing I want to achieve, even if
            in
            > > my opinion he is regrettably going in the wrong direction. Now it
            > > seems he has left the group and in any case has taken offence at
            > > anything I do or say, I am posting it here regardless. I hope you
            > > find it of interest.
            > > >
            > > >
            > > > The 2nd law of thermodynamics was what got me interested in
            > Physics
            > > in the first place. My school teachers, and later my University
            > > lecturers could not answer the questions I had. I had to go out
            and
            > > get those answers myself. Some of you may be interested.
            > > >
            > > > To flip through to the end, I believe that it is theoretically
            > > possible to violate the 2nd law and generate useful work out of
            > heat
            > > at ambient temperature. (Whether or not it is practical I am
            > hesitant
            > > to claim. I have some schemes, but they may be flawed). Now you
            may
            > > tell me that this is nonsense, that the 2nd law is one of the
            best
            > > authenticated and most reliable laws in Physics, but to that I
            > would
            > > say that that is because very few people are seriously
            questioning
            > > it. It is considered a dead subject at University level. (When I
            > had
            > > some searching questions on its validity, I was told that I would
            > be
            > > better off digging out retired physicists than current ones.)
            > > Relativity, on the other hand, is constantly poured over in the
            > hope
            > > that a flaw will be found. On those grounds alone, I have much
            more
            > > trust in Relativity than I do in something like the 2nd law which
            > is
            > > at least twice as old. New discoveries in Physics are constantly
            > > being made, but who is it that is checking the relevance to 200
            > year
            > > old laws?
            > > >
            > > > In what follows, there is some fairly fundamental but little
            > > discussed concepts. if what follows is unfamiliar to you, I
            suggest
            > > you take some time to digest it.
            > > >
            > > > To violate the 2nd law, what you would have to do is take the
            > > random microscopic fluctuations in energy levels due to heat and
            > > harness them into some macroscopic energy level difference. What
            > got
            > > me interested in the first place was that it is evident that this
            > can
            > > be done on a larger scale with suitable engineering. For example,
            > > random motions of the wrist can cause the mainspring of an
            > automatic
            > > watch to be wound up. Why should this be impossible on the
            > > microscopic scale using Brownian motion? If there is
            fundamentally
            > > impossible, then searching for a mechanism would be a waste of
            > time.
            > > So the first question is:
            > > >
            > > > Is a violation of the 2nd law of thermodynamics possible in any
            > > conceivable self-consistent Universe?
            > > >
            > > > The definition of the 2nd law I use is that of Boltzmann (I
            > believe
            > > it is inscribed on his tombstone): In any isolated system ds >= 0
            > > where s = ln(w) and w (which I shall use for omega) is the number
            > of
            > > microstates that are consistent with one particular macrostate.
            To
            > > avoid the possible objection that the distinction between
            > macrostates
            > > is subjective, I say that if it is possible to devise a practical
            > > machine that can harness energy when one microstate changes to
            > > another microstate, then the two microstates can be described by
            > > different macrostates.
            > > >
            > > > The 2nd law is a statistical law. If we suppose that a system A
            > has
            > > a total number of microstates, wMax, and that the microstates are
            > all
            > > of equal probability (i.e equal energy), then each microstate
            will
            > > have an even population over infinite time. However, typically, a
            > > vast majority of those microstates will correspond to one single
            > > macrostate. As a result, it will appear that the system will go
            to
            > > that single macrostate, and the probability of any other
            macrostate
            > > spontaneously coming into existence is so infinitesimal it is not
            > > worth considering.
            > > >
            > > > As an example, consider an ideal gas in an enclosed volume.
            There
            > > are a very large number of possible ways to distribute the
            > molecules
            > > around the volume. a much smaller number correspond to all of the
            > > molecules being in one half of the volume. However there is no
            > > difference in probability (there being no energy interactions
            > between
            > > the ideal gas molecules) between one microstate in which the
            > > molecules are evenly distributed and one in which all are in one
            > > half. It is purely the statistics which determine that the former
            > > state is the one we almost inevitably see. If, however, all the
            > > molecules did move into one half, it would be practical to erect
            a
            > > barrier which would allow us to harness energy when the molecules
            > > reverted to the almost infinitely more probable state of even
            > > distribution. This means that half in one side comprises a
            > different
            > > macrostate.
            > > >
            > > > Now let us suppose we could erect a barrier between the two
            > halves
            > > (analogous to one populated by Maxwell's demons) which only
            allowed
            > > passage in one direction. The molecules in the gas are in
            constant
            > > motion. They will all come in contact with the barrier at one
            time.
            > > If they do, they will pass through to the more populated half and
            > be
            > > denied passage back to the less populated half. The end result
            will
            > > be the highly improbable state described above where all the
            > > molecules are in one half of the volume. They could then be
            allowed
            > > to expand into the empty half while doing useful work; the
            > > temperature of the system would drop. Such a scenario is deemed
            > > impossible by the 2nd law. To put it another way, if such a
            barrier
            > > could exist, the 2nd law could be violated.
            > > >
            > > > When you try to engineer such a barrier, you soon find the
            > problem.
            > > (It does not matter if you try to engineer with a population
            > > difference as described above or the more complex individual
            > > potential energy difference as described by Maxwell when he
            > > postulated his demon that could create a spontaneous temperature
            > > difference). Such a membrane cannot be engineered easily. On the
            > > microscopic level where such a mechanism would have to be
            > engineered,
            > > processes tend to be reversible. If the probability of the
            forward
            > > process is exactly the same as the reversible process, then there
            > is
            > > no net flow across the barrier. We are used to mechanisms on the
            > > macroscopic scale that can have a unidirectional preference. the
            > > ratchet on an automatic watch is such a process. However such
            > > mechanisms depend on their macroscopic nature to achieve this
            > > irreversibility. The watch ratchet is unidirectional because when
            > the
            > > pawl descends into the ratchet, the excess energy is dissipated
            as
            > > heat. On the microscopic level, there is no such thing as heat or
            > > dissipation. the pawl descending into the ratchet will bounce
            back
            > to
            > > the same height as it descended from. the process is entirely
            > > reversible. You might postulate some system of sprung trap-doors
            to
            > > allow the molecules to flow in one direction, but such a system
            > would
            > > not work on the microscopic level because as soon as they closed,
            > > they would bounce back open again.
            > > >
            > > > What is require is some process that is essentially asymmetric
            on
            > > the microscopic level. The way this asymmetry is expressed is in
            > > terms of time asymmetry. If you could film the interactions
            between
            > > two particles, and then play the film backwards, would it be
            > > possible, without any prior knowledge of which process was real
            and
            > > which had been played backwards to say which film was of the real
            > > event? I find it particularly ironic that the essential
            > > irreversibility of events on the macroscopic level is a
            consequence
            > > of the essential reversibility of processes on the microscopic
            > level.
            > > >
            > > > to return to the original question. The answer is that a
            > violation
            > > of the 2nd law of thermodynamics is possible in a conceivable
            > > universe, but only if that universe contains processes that are
            > > irreversible on the microscopic level.
            > > >
            > > > the next question to be asked is do we live in such a Universe?
            > > >
            > > > ...To be continued.
            > > >
            > > > Bob Lerwill
          • Charles Ford
            ... Please ===== Charles Ford KC5-OWZ cjford1@yahoo.com cjford1@swbell.net __________________________________________________ Do You Yahoo!? Sign up for SBC
            Message 5 of 8 , Jul 2, 2002
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              --- chudslayer <BordersChess@...> wrote:
              >
              > On a slightly different track, do you recall that a few months ago
              > researchers anounced that a material whic allows heat flow in only
              > one direction is theoretically possible? (I can look up the URL if
              > anyone wants it) They did not suggest that it could be used to
              > create temperature differences from ambient heat, but rather that it
              > might be a useful insulating material (think of a thermos bottle that

              Please



              =====
              Charles Ford
              KC5-OWZ
              cjford1@...
              cjford1@...

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            • chudslayer
              ... ago ... only ... if ... that it ... that ... One-way street planned for heat. Physicists design material that conducts one way and insulates the other.
              Message 6 of 8 , Jul 2, 2002
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                --- In AMBIENTENERGY@y..., Charles Ford <cjford1@y...> wrote:
                >
                > --- chudslayer <BordersChess@h...> wrote:
                > >
                > > On a slightly different track, do you recall that a few months
                ago
                > > researchers anounced that a material which allows heat flow in
                only
                > > one direction is theoretically possible? (I can look up the URL
                if
                > > anyone wants it) They did not suggest that it could be used to
                > > create temperature differences from ambient heat, but rather
                that it
                > > might be a useful insulating material (think of a thermos bottle
                that
                >
                > Please
                >
                >
                >
                > =====
                > Charles Ford
                > KC5-OWZ
                > cjford1@y...
                > cjford1@s...
                >


                One-way street planned for heat.

                Physicists design material that conducts one way and insulates the
                other.

                http://www.nature.com/nsu/020304/020304-2.html
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