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On Jan 24, 5:58 pm, dwhig...@peoplepc.com wrote:
> On Jan 23, 7:57 pm, "rayoha...@yahoo.com.ar" <juanp...@gmail.com>
> wrote:
>
> > On Jan 23, 8:03 pm, dwhig...@peoplepc.com wrote:
>
> > > On Jan 21, 5:32 am, Pentcho Valev <pva...@yahoo.com> wrote:
>
> > > > On Jan 21, 11:59 am, "rayoha...@yahoo.com.ar" <juanp...@gmail.com>
> > > > wrote:
>
> > > > > On Jan 21, 3:52 am, Pentcho Valev <pva...@yahoo.com> wrote:
>
> > > > > > On Jan 21, 4:46 am, "rayoha...@yahoo.com.ar" <juanp...@gmail.com>
> > > > > > wrote in sci.physics:
>
> > > > > > > On Jan 20, 10:21 am, Pentcho Valev <pva...@yahoo.com> wrote:
>
> > > > > > > > On Jan 18, 2:58 pm, blackboab <blackb...@gmail.com> wrote in
> > > > > > > > sci.physics:
>
> > > > > > > > > The second law of thermodynics says that the direction of time is
> > > > > > > > > dictated by the increase of entropy,.
>
> > > > > > > > Does it? Why don't you read Jos Uffink's paper:
>
> > > > > > > >http://philsci-archive.pitt.edu/archive/00000313/
> > > > > > > > Jos Uffink: "This summary leads to the question whether it is fruitful
> > > > > > > > to see irreversibility or time-asymmetry as the essence of the second
> > > > > > > > law. Is it not more straightforward, in view of the unargued
> > > > > > > > statements of Kelvin, the bold claims of Clausius and the strained
> > > > > > > > attempts of Planck, to give up this idea? I believe that Ehrenfest-
> > > > > > > > Afanassjewa was right in her verdict that the discussion about the
> > > > > > > > arrow of time as expressed in the second law of the thermodynamics is
> > > > > > > > actually a RED HERRING."
>
> > > > > > > > Jos Uffink:http://www.phys.uu.nl/igg/jos/
>
> > > > > > > > Pentcho Valev
> > > > > > > > pva...@yahoo.com
>
> > > > > > > i had looked that article. it is interesting, but any consideration of
> > > > > > > thermodynamics that not relate this to statistical mechanics seems to
> > > > > > > me out of target. and it get lost in mathematical considerations about
> > > > > > > things as for example
> > > > > > > when a process is irreversible or not. it get lost, because if you not
> > > > > > > look at the microscopic level, then you cannot look for a basis from
> > > > > > > which assume good sense. take a look to the article and u will see
> > > > > > > that.
>
> > > > > > You mean there is no "good sense" in classical thermodynamics?
> > > > > > Ironically, the alleged STRENGTH of that science was that it was
> > > > > > PHENOMENOLOGICAL, that is, it did not have to deal with the
> > > > > > microscopic level and yet it could give, through rigorous deduction,
> > > > > > valuable results. But you can verify this. Take a look at Clausius
> > > > > > 1850 deduction of the original version of the second law of
> > > > > > thermodynamics: "It is this maximum of work which must be compared
> > > > > > with the heat transferred. When this is done it appears that there is
> > > > > > in fact ground for asserting, with Carnot, that it depends only on the
> > > > > > quantity of the heat transferred and on the temperatures t and tau of
> > > > > > the two bodies A and B, but not on the nature of the substance by
> > > > > > means of which the work is done.":
>
> > > > > >http://web.lemoyne.edu/~giunta/Clausius.html
> > > > > > "Ueber die bewegende Kraft der Warme" 1850 Clausius: "It is this
> > > > > > maximum of work which must be compared with the heat transferred. When
> > > > > > this is done it appears that there is in fact ground for asserting,
> > > > > > with Carnot, that it depends only on the quantity of the heat
> > > > > > transferred and on the temperatures t and tau of the two bodies A and
> > > > > > B, but not on the nature of the substance by means of which the work
> > > > > > is done.....If we now suppose that there are two substances of which
> > > > > > the one can produce more work than the other by the transfer of a
> > > > > > given amount of heat, or, what comes to the same thing, needs to
> > > > > > transfer less heat from A to B to produce a given quantity of work, we
> > > > > > may use these two substances alternately by producing work with one of
> > > > > > them in the above process. At the end of the operations both bodies
> > > > > > are in their original condition; further, the work produced will have
> > > > > > exactly counterbalanced the work done, and therefore, by our former
> > > > > > principle, the quantity of heat can have neither increased nor
> > > > > > diminished. The only change will occur in the distribution of the
> > > > > > heat, since more heat will be transferred from B to A than from A to
> > > > > > B, and so on the whole heat will be transferred from B to A. By
> > > > > > repeating these two processes alternately it would be possible,
> > > > > > without any expenditure of force or any other change, to transfer as
> > > > > > much heat as we please from a cold to a hot body, and this is not in
> > > > > > accord with the other relations of heat, since it always shows a
> > > > > > tendency to equalize temperature differences and therefore to pass
> > > > > > from hotter to colder bodies."
>
> > > > > > If Clausius deduction is invalid (try to discover why it IS invalid),
> > > > > > then you are right: there is no "good sense" in classical
> > > > > > thermodynamics.
>
> > > > > > Pentcho Valev
> > > > > > pva...@yahoo.com
>
> > > > > no, classical thermodynamics has sense, it is a very good theory, but
> > > > > it has no sense when u try to link it with arrow time, that is another
> > > > > story, I had expressed wrong (the word this sings to a preferred arrow
> > > > > time direction, sorry for that), and u then had a bad interpretation,
> > > > > it is my fault, read entirely what i´d writed.
>
> > > > Let me translate yout statement that classical thermodynamics "is a
> > > > very good theory, but it has no sense when u try to link it with arrow
> > > > time" in the following way: The version of second law saying perpetuum
> > > > mobile of the second kind is impossible is correct; the version of the
> > > > second law saying the entropy always increases is nonsense. I disagree
> > > > with the first part (perpetuum mobile of the second kind IS POSSIBLE)
> > > > but this disagreement of mine is irrelevant for the moment.
>
> > > I responded 4 hours earlier to let you know I had already been there
> > > 18 years ago. Please let us hear your version. DWH
>
> > >  If the
>
> > > > principle of entropy increase is really nonsense, the devastation
> > > > suffered by science and caused by this particular nonsense is much
> > > > greater than the devastation caused by Einstein's 1905 false light
> > > > postulate. Just remember this:
>
> > > >http://web.mit.edu/keenansymposium/overview/background/index.html
> > > > "The law that entropy always increases, holds, I think, the supreme
> > > > position among the laws of Nature. If someone points out to you that
> > > > your pet theory of the universe is in disagreement with Maxwell's
> > > > equations--then so much the worse for Maxwell's equations. If it is
> > > > found to be contradicted by observation--well, these experimentalists
> > > > do bungle things sometimes. But if your theory is found to be against
> > > > the second law of thermodynamics, I can give you no hope; there is
> > > > nothing for it but to collapse in deepest humiliation." Sir Arthur
> > > > Eddington (The Nature of the Physical World, 1915)
>
> > > > Pentcho Valev
> > > > pva...@yahoo.com- Hide quoted text -
>
> > > > - Show quoted text -
>
> > quote:
> > {In 1990 an early version of my theory stated: " The universe is a
> > pure
> > system and inasmuch as it is the only system, cannot react with any
> > other system adiabatically or otherwise.  Net entropy in such a system
> > is zero and therefore the universe must recycle, and is the only
> > perpetual motion machine of the second kind." This was copyrighted by
> > me,of course. Regards, Dwain W. Higginbotham }
>
> > i think that this is a better look than before.  agree with the fact
> > that ¨universe must recycle, and is the only perpetual motion machine
> > of the second kind.¨  not sure with
> > recycle, no one knows what happens if big bang its true, and big
> > crunch also. but main theories are consistent with the assumption that
> > entire universe corresponds to microcanonical ensemble, that is,
> > universes do not interact with another thing because by definition
> > there is not another thing.
>
> > but I disagree with ¨Net entropy in such a system is zero¨. I think
> > that the reason for this mistake comes from a misconception of how to
> > relate entrophy with the system in this case, that is, universe. for a
> > good uses of entrophy, u must think in the main basis of it, that is,
> > entrophy is a measure of ignorance (see c. shannon famous paper).
> > I think that resume some basic of this point of view related to
> > mechanical statistics will be a good exercise. suppose that at the
> > micro level description the vector x=(x1,...,xN) in R^N, describes the
> > state of the system at time t, so the phase space of the system is
> > some subset of R^N,  say Q is the phase space. then an order parameter
> > O_f, is just a number that can be calculated from the average of some
> > function f(p) over some distribution probability {p} over Q.
> > now, the value of Q_f depends on how trayectories behaves on Q. and
> > that depends on some parameters that may affect the hamiltonian (think
> > in some kind of thermodynamical variables as for example could be a
> > magnetic field B).
> > now, entrophy is such an order parameter, a praticular one that we
> > denotate S. now for things has sense it is important that {p} where
> > well defined on Q, in principle that is by mean of avergaing over all
> > available trayectories on Q from time zero to infinity (birkhoff´s
> > theorem).
> > so in essence, what measures entrophy ?? think that we can measure
> > over the system some set of order parameters O_f1,O_f2,...,O_fr, now
> > assume that we know  how to calculate this order parameters from {p}.
> > and that order parameters are all that we can measure from the system.
> > then S(O_f1,..,O_fr) is the amount of information that we need to
> > establish the particular trajectory that the system follows, our
> > ignorance comes, by averaging over all initial conditions and then by
> > mean of {p} looking how much ¨consistent¨ is each initial condition
> > with the values of O_f1,..,O_fr. in other words, if we choose a
> > suitable set O_f1,...,O_fr the we restrict the system to only one
> > trajectory possible consistent with that set, that is S=0. if it is
> > not the case, the S measures how much the set O_f1,...,O_fr fail to
> > ¨restrict¨ the choose of a trajectory. if the set O_f1,...,O_fr is
> > measured, then S measures the fail to restrict the choose of the real
> > trajectory, because O_f1,...,O_fr can´ t be inconsistent with the real
> > trajectory.
>
> > now all this has sense for system where {p} is defined (system at
> > equilibrium, or system where {p} admits definition by means of
> > averaging all trajectories from t=-infinity to t=infinity), what
> > happens when this is not the case ?? the universe is one of this
> > cases. well here a more complicated considerations are needed, and in
> > particular the considerations can be system dependent in order to at
> > least admit some simplifications. but in general one can define a set
> > O_f1(t),...,O_fr(t) and S(t)
> > , then S(t) is the ignorance about the initial condition at time t.
>
> > so, in practice, we measure some things as voume of universe, and
> > temperature, etc, all variables that approximates some set
> > O_f1(t),...,O_fr(t). and from it speculate about if S(t) grows or
> > decreases or remain constant.
>
> > if big bang is true, then those considerations says that S(t) grows
> > with time. so entrophy can´ t be zero in that case.
>
> > best regards
> > rayohauno
>
> "Net entropy in such a system is zero---" means a perpetual motion
> machine can never wear down but since we see what we think is some
> evidence of "entropy" there has to be some mechanism for handling it,
> and I think I have a pretty good idea about how Mother Nature copes
> with the problem. Also, if we live in the only perpetual motion
> machine, it always was and always will be, so there was no "big bang".
> Regards, DWH.    PS to P.V., Relax. I thought we might be stepping on
> each others toes..

quote:
{Net entropy in such a system is zero---" means a perpetual motion
machine can never wear down but since we see what we think is some
evidence of "entropy" there has to be some mechanism for handling it,
and I think I have a pretty good idea about how Mother Nature copes
with the problem. Also, if we live in the only perpetual motion
machine, it always was and always will be, so there was no "big
bang". }

I think that this is not true.
why net entropy must be zero ??
if i understand what u say, then there aren´ t models that in a
microcanonical formulation has nonzero entropy and are
perpetual machines. I think that this is false, because I think that
any chaotic system which has a cuasi periodic attractor may be
considered a perpetual machine with nonzero entropy, as for example a
lot (in orden N>>1) of rossler oscilators in the chaos region, coupled
and in resonance (in order that the sum of all of them behaves as an
perpetual motion machine, and not merely as a heat bath).
second, from the point of view of my description, u statement has no
sense, because in my description nonzero entropy
is related to our ignorance of the microstate of the system (universe
in this case). at the beginning of the big bang everything is in one
point, so there is no ignorance about the microstate of the system,
zero entropy, but now, clearly
ignorance about the microstate of the system exists.

best regard
rayohauno