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Entropy’s Great... Oversights, PART 1
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SECTIONS
Entropy’s Great...
Oversights
The Second Law of Thermodynamics
Oh, My Ergodic Hypothesis...
Brownian Motion,
“Brownian Entropy” and “Entropo-dynamics”
The “Arrow of Time”
Entropy as
“Disorder”
A Gedanken Experiment
Thermodynamic Equilibrium
“Time
Reversal”
“Hyper-Dimensional”, “Hyper-Topological” Time
Digression: Maxwell’s
Demon
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The Second Law of Thermodynamics
The physics of thermodynamics in general, and its 2nd law in
particular, are actually an extremely
complex study. Almost all of its evolution has occurred in the last 200
years (of the 2nd Millennium). Its names read like a who’s who of
physics: Kelvin, Carnot, Clausius, Boltzmann, Maxwell, Gibbs, Planck,
Bose, and even Einstein, the
Elvis of Science.
One of the principle... oversights in thermodynamics,
in fact in entropy, one that remains unacknowledged, is one that most
scientists will dispute, at least at first. They will say that it is not an oversight, even
of the “ordinary” sort. We will spend a bit of
time clarifying this.
One of the simplest of the
accepted expressions of the 2nd law of thermodynamics, the law of entropy,
is:
-
In an isolated
system: ΔS
4 ΔQ/T
> 0
where S is entropy
(a “state function” of the system), Q
is heat, and T is the absolute temperature at which the heat is
transferred (and the symbol Δ represents change, e.g. in entropy)
A state function does not depend on e.g. any history of system
activity, or on outside influences; in thermodynamics, the state of the
system is determined by the positions and velocities of all the particles. The qualification of it being an isolated system is
needed because increases in the entropy of a system can easily occur by
the transfer of heat to-from something outside the system (this is how
heat engines work, although it depends on where you draw your system
boundaries), unless it is isolated. It is a measure of how much of a
systems energy is being converted to heat, which tends to make it less
accessible to do work (in the sense of force times distance).
We should also point out that
the definitional expression for entropy above depends on its being derived from “equilibrium
thermodynamics”, where... this can get confusing... all heat energy
transfers take place between two heat reservoirs that are at the “same equilibrium temperature”
(which transfers are theoretically impossible), and thus
making the
single absolute temperature T unambiguous (except e.g. when one takes into account Maxwell’s
distribution of molecular kinetic energies; a subtle point, but
eventually it will be seen to be essential). One of the reasons this gets sticky, as yet unappreciatedly, is that — classically —
heat can’t be transferred when there is no temperature difference;
i.e. net heat transfer is
classically zero if the temperature difference is zero. There is always some
heat energy being transferred each way,
even at “equilibrium”, but it “averages out to
zero”. (Reminder for emphasis:
temperature is a classical thermodynamics concept, i.e. a macroscopic
level concept, the average
kinetic energy of a
sufficiently large ensemble of
molecules. Physics has generally ignored the problem of working out
how “temperature” needs to be conceived at the microscopic or molecular
level, where Maxwell’s distribution won’t
give us an average over a
sufficiently large macro-ensemble.) So the usual practice has been to say that there is an
“infinitesimal” temperature difference, etc.
This is on the macro level. BUT... even if we consider only
“equilibrium thermodynamics”, on a microscopic level net energy transfer
between-among molecules essentially always takes place with a non-equilibrium
temperature difference between the molecules (taking the kinetic energy of
each molecule as its “average kinetic energy” and thus its absolute temperature),
thus making the concept of entropy based on the
fundamental equation above locally meaningless and invalid. And,
even if we gloss over this fact, this energy transfer
is often anti-entropic
(since heat is often transferred from a lower temperature molecule to a
higher temperature molecule, even though it is more often transferred the
other way).
This actually means that studies of “non-equilibrium thermodynamics” are
essential to studies of “equilibrium thermodynamics”, which has not
yet been noticed, let alone fully appreciated, by physics.
What is perhaps the main... oversight in entropy, the
2nd law of thermodynamics, can be
summed up in one word (one likely to provoke controversy in this context) :
This is where scientists might start to say that
“but we knew that already”. The term
“ergodic” comes out of statistical mechanics,
a branch of thermodynamics where the mathematics of the “disorder” of
molecules is related to — bridged to — the classical treatment of thermodynamics (which
doesn’t theorize in terms of molecules and atoms). We will attempt to explore this more in a bit,
but it is very complex field, even for physicists. So let us first sum
up in one word that both scientists and non-scientists are sure to recognize:
Everyone knows what a “house
of gambling” is, and everyone is familiar
with the fact that you can count on “the house” having an “edge”, an
advantage that means that in the long run they will have an
“overwhelming propensity” to “win”. But, everyone also knows that there are chances
for a “lucky gambler” to “win”, and even to sometimes “break the bank”. This
wisdom is not expressed, nor even allowed for, in the standard
2nd law of thermodynamics, the accepted law of entropy.
The standard statement of the
2nd law of thermodynamics is more-or-less equivalent, in gambling terms, to saying
that:
-
the gambling house of entropy not only
has an edge,
entropy wins every bet,
without fail,
never losing even once.
As much as one may
“subjectively” feel this to be true of “one-armed bandits” (an “emotional
truth”?!), we generally acknowledge that the ordinary gambler will win at
least a few bets before losing... her blouse.
Of course, our usual simple model of gambling has a
terminal state for each gambler, who can “go
broke”, permanently; the house can also “go
broke” permanently, but with greatly lesser probability of doing so than
the usual gambler. Unlike in our model of thermodynamics, in our usual
simple gambling model these “broke” states do not have
the possibility of changing back into “in the game” states. So, in this at least, our gambling
simile leaves something to be
desired, since in thermodynamics, even if the system achieves any
(accessible) highest entropy state, it will still be able to eventually transition
back to any (accessible) lowest entropy state, and vice-versa.
This last idea, of being able
to transition not only from the lowest entropy states to the highest, but
from the highest to the lowest, and what’s more, to do it on a continuing
basis, is inherent in the thermodynamic concept of “ergodic”. As we
will see below, it is trivially true that:
And even though scientists “already know” that this
falsifies the 2nd law of thermodynamics, they still hold that the 2nd law
is a law of science, and not
merely of that pragmatic but ultimately artistic field of study, engineering. Both
science and engineering suffer from this attitude, and we all suffer
accordingly because every day science is exercising — or justifying the
exercise of — ever more total
control over “order”
and “disorder” in our daily lives.
(The Bible has some important things to say about “all
rule and all authority and power”. See 1st
Corinthians 15:24.)
It sounds satirical because it most naturally is in
this situation, but when we try to find what ultimate truth there is in
the second law, we will eventually find it to reduce to the statement of
the fact that more
highly probable events occur with greater probability and lower
probability events occur with lesser probability, but they all occur. Let’s
make that slightly more formal:
-
Thermodynamic entropy, a
state function S of an ergodic process, is actually a
(relative?) measure of the relative amount of time that the process will
spend in a given state (or perhaps set of states). The reason ΔS
seems to increase montonically — or
“quasi-monotonically” if we think of the increase in terms of Boltzmann’s
concept that it happens with “overwhelming probability”, not with the
strict “inevitability” of the classical second law —
is that, since the ergodic process will on the
average spend more time in high entropy states, it follows that if it’s in
a low entropy state, on the average it must head toward higher entropy
states in order to spend more time there. If that sounds a tiny bit
circular, it is. This approach to analyzing entropy has yet to be noticed
by physicists, and it will take a major but absolutely necessary revision
of statistical mechanics to make it satisfyingly formal.
But there is more, much much more. We need to uncover
many more... oversights, and start to evaluate their synergistic effect on
science.
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SECTIONS
Entropy’s Great...
Oversights
The Second Law of Thermodynamics
Oh, My Ergodic Hypothesis...
Brownian Motion,
“Brownian Entropy” and “Entropo-dynamics”
The “Arrow of Time”
Entropy as
“Disorder”
A Gedanken Experiment
Thermodynamic Equilibrium
“Time
Reversal”
“Hyper-Dimensional”, “Hyper-Topological” Time
Digression: Maxwell’s
Demon
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Oh, My Ergodic Hypothesis...
When the term “erogodic”
was used above, many people who consider themselves scientists almost certainly said to
themselves “we know that already”, and mentally dismissed the whole show,
perhaps even failing to read on. This is partly correct, since the “ergodic
hypothesis”, which came out of the work of Poincaré and Boltzmann, and is
considered to have provided the foundation of the statistical mechanics of
Boltzmann and Gibbs, is over a
hundred years old.
The Ergodic Hypothesis
(usually formally attributed to Boltzmann) has many statements known or thought to be equivalent. One of them is that every
thermodynamic system is ergodic, i.e. it either has a large finite number of
states or microstates, each of which — if “accessible” — will be revisited
infinitely many
times as time increases, or is an infinite system in which every
microstate will be approached arbitrarily closely any number of times as
time increases.
Relatedly, Boltzmann, after some years, changed his earlier stand that
his statistical mechanics (based on the work of James Clerk Maxwell; the
American Josiah Willard Gibbs Jr. later also developed statistical mechanics
independently) showed that entropy would always increase (with the
relevant qualifications) to his later stand that there is an “overwhelming
propensity” for it to increase. The ergodic hypothesis is considered to be
a (an) hypothesis since it is thought that the time needed to effectively
observe this phenomenon (as usually conceived) in the laboratory would take more time
(perhaps 1030 years, as suggested by Richard Feynman) than
the universe is expected to be in existence.
But what is the “ergodic
hypothesis”? Let us give a quick series of definitions:
-
a “stochastic process” is a
probabilistic process with a parameter that more or less represents time; a
stochastic process can be finite, i.e. having only a finite number of states, or
continuous, i.e. having effectively an uncountably infinite number of states
-
a “Markov process” is a
stochastic process, a combination of a set of states, one of which the process is said to be
“in”, with a set of probabilities for transitioning between those states that
depends only on the state that the process is said to be in; (this last
condition distinguishes it from the more general concept of stochastic process); any
state that has a sequence of state transitions with non-zero probabilities
leading to it from the current state is called “accessible”
-
an “ergodic process” is a
Markov process in which every state that is accessible (and remains so
throughout the “trajectory”, the sequence of states and-or state transitions that
the process goes through) will be revisited infinitely many
times, with probability
1 (effective certainty, Boltzmann’s overwhelming propensity)
-
the “ergodic hypothesis” in
thermodynamics is that
thermodynamic systems are ergodic, i.e. a given (accessible) state of the system (given in
terms of thermodynamic micro-properties, e.g. particle momenta) will recur any
number of times (even if it is a lowest entropy state), even though it may take vast
periods of time to do so (Richard Feynman suggested 1030 years for a thermodynamic system such as a
room full of air at STP)
This much (just above) is publicly accepted
by physicists.
If asked, physicists will say that the ergodic hypothesis does not really falsify the 2nd law of thermodynamics
because... well, because of the overwhelming propensity thing, and the
1030 years, and so on. But, in fact:
What has been overlooked? even... oversighted?
-
What has been... oversighted in physics is that, in fact:
Ergodicity really does falsify the
2nd law of thermodynamics,
i.e. of strictly monotonically increasing entropy,
despite the
fact that physicists don’t
think of it as doing so.
-
It turns out that physicists have... oversighted that:
Ergodicity also implies the overwhelming propensity
of change
in the opposite direction, that of
decreasing entropy;
even if
it only seems to be a far distant eventuality, decreasing
entropy is an
inevitability, ergodically-thermodynamically,
and even if the system will spend almost all its time in the high entropy states.
A thermodynamic system will ergodicly re-attain even the lowest entropy levels
an infinite number of times as the system evolves, and whenever any level is
re-attained it means that the sum of the increases and decreases (from any of
the previous times it was at that level) is strictly zero.
-
Entropy is an
“Inevitability of Spending
More Time at ‘High’
Levels Property”,
and not the currently espoused “inevitability
of the increase of the entropy state function property” (any more or less than it
is an “inevitability of decrease property”).
-
The second
law of thermodynamics is currently (but only temporarily?!)
adequate as an
engineering at the classical physics level of
existence
law,
but, as a law of science,
The 2nd Law of
Thermodynamics is SCIENTIFICALLY FALSE.
We might continue to overlook this fact on the same grounds
(of the overwhelming propensity of what we notice, etc.), except that
we are dealing here with science, and this overlooking would be — is — a
falsification of
science. Also, e.g., this... oversight has profound
impact on other parts of physics, particularly on the much loved
(-not-wisely-but-too-well) concept of “the
arrow of time”.
More on this later, after we first
go back over some of the basics.
-
An ergodic process is not
only a Markov process,
an ergodic process is a stochastically cyclical process, and
-
a state function of a cyclical
process is a cyclic function, and
-
a cyclic function cannot be
strictly monotonically increasing;
and it is generally agreed that:
which means that (since entropy is
a state function of such a system)
which means that
If someone tried to make the case that the paradigmatically standard cyclical trigonometric function sin(ax)
was a strictly monotonically increasing function, we would question his sanity,
or at least the quality of his education. If he then tried to make the case that
it would be strictly monotonically increasing if the coefficient a of
the variable x were small enough, say a = 10-30...
well, at best we would probably smile at his childlike naiveté
(or his childish naïveté,
or some such). In any case we would not allow it as either competent mathematics or
competent science.
But, if he picked a stochastically
cyclical function, with an implicit coefficient a = 10-30,
and displayed it waving the flag of science, well, then it would be
called... the 2nd law of thermodynamics.
Let us note that in general:
-
any
ergodic system violates a generalized 2nd Law (as regards a state function such
as entropy)
(It must be generalized to make sense
in all cases.)
-
any state function of any ergodic process
or system has no long term tendency to increase or decrease;
pick an ergodic process or system, pick a state function, pick a state, find the
value of that state function for that state, and note that since that state is
revisited an infinite number of times and the state function takes on that same value
an infinite number of times, always decreasing-increasing as much as it
increased-decreased to re-attain that value, there can be no long term tendency
of that function to increase or decrease
We should also note that the concept of “tendency
to increase” in this context is not
actually well-defined. No one has carefully delineated what this actually meant.
For example, if we put our ergodic process in an arbitrary “lower
entropy” state, and do this many times, it might, but not necessarily so,
tend to transition to a “higher entropy” state. (How many state transitions from
the original state must we observe to calculate this tendency?) We could call
this a “tendency to increase”. We could also
look at the state function values for all the states of that same lower level
entropy, but only one time for each state, and get a different picture of the
tendency to increase. And, as we saw just above,
we could also put the ergodic process in that first state and watch it for a
very long period of time, see it revisit the “lower entropy” state any number of
times, and note that this means there is no “long term tendency” for it to
increase or decrease.
-
The “tendency to
increase” of a state function of an ergodic
process is NOT WELL-DEFINED.
-
We have also overlooked that we have not (well-)
defined how we assign a given entropy state function value to a given state.
We may think we have, but does it accurately reflect either the
“tendency to increase”, which is
obviously not well-defined, or the “tendency
to spend time in that state”, which is
“more well-defined”.
It can also be noted in passing that
technically:
-
An ergodic process is a
theoretical variant of a classical perpetual motion machine.
(Although thermodynamic systems model molecules, or at least atoms of an
idealized noble gas, that theoretically go on bouncing around forever, this is
not considered useful work, required at least implicitly in most statements of
perpetual motion. But if a thermodynamic system —
isolated, for obvious reasons — re-attains any state, then it
re-attains infinitely many times 1 or more states associated with useful work,
or its possibility, even if the whole kit-n-kaboodle also eventually goes down a
black hole or into a “big crunch” infinitely many times.)
There is another essential factor
in this picture. Above we have looked at 2nd law violating entropy decreases
over
the long run, but there is a short run, as well. This short run can be summed up
in one word:
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SECTIONS
Entropy’s Great...
Oversights
The Second Law of Thermodynamics
Oh, My Ergodic Hypothesis...
Brownian Motion, “Brownian Entropy” and
“Entropo-dynamics”
The “Arrow of Time”
Entropy as
“Disorder”
A Gedanken Experiment
Thermodynamic Equilibrium
“Time
Reversal”
“Hyper-Dimensional”, “Hyper-Topological” Time
Digression: Maxwell’s
Demon
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Brownian Motion,
“Brownian Entropy” and
“Entropodynamics”
Another... oversight in the standard 20th (and now early
21st) Century concept of
entropy is Brownian motion. When we have small visible particles in a clear
liquid, we can see them move in some “orderly” fashion with the flow of the
liquid (usually no flow, of course, when we look
for Brownian motion), but also erratically, randomly in “small” movements. By
serendipity, luck or God’s design, e.g. the sizes of atoms and particles, the
distances moved, and the sensitivity of our eyes to detect these movements, we
can even see these movements unaided by microscopy, although we could have
considered ourselves very lucky even if they could only have been detected
at all.
Rarely, but inevitably, these random motions can take a
given particle a great distance in a short time. By the same token, large
macroscopic particles (think of lots of very small ones, however distributed),
although they usually experience only small changes in momentum-energy,
can experience very large changes very
quickly. These
changes are almost always, but not
always, damped by e.g. viscosity-like substances too quickly to be observed.
And, to top it off, any such motion that was also observed would most likely
be attributed to something else (e.g. to hydrodynamics rather than
“entropodynamics”),
which is probably all too common in science. Chaos theory in part deals with
some of the wilder extrapolations of these types of combinations of lots of such
seemingly small events, e.g. from the motions of a butterfly’s
wing to the “precipitation” (more humorous, but also probably much more accurate
than “causation”) of a hurricane (uhh, tornado, actually), i.e. from, or at least through, Brownian
thermodynamics to classical hydrodynamics.
-
To anticipate, somewhat: there is an essential set of
relationships among 1) 2) thermodynamics, 3) Brownian motion, 4) entropy with its overlooked
“Brownian Entropy”, and 5) chaos theory,
synergistic relationships that
have been stoutly overlooked by the scientific community.
Brownian motion is considered to be fairly well understood
by science, and is held to verify the atomic and thermodynamic nature of matter.
We have ignored some quite obvious implications of Brownian motion for
thermodynamics, but at least it should be
easy to begin applying that theory to e.g. any probabilistic kind of entropy.
Just as the position of a small particle in a
liquid is made to
jiggle so erratically that some scientists model the trajectory (here of the
particle) as having its
first derivative discontinuous almost everywhere, so entropy (even in an isolated system)
rapidly and erratically alternates direction
(here in 1 dimension),
decreasing
for an instant, increasing for an instant, etc., even — or especially — if the system is at
“thermal
equilibrium”.
It is somewhat as if we placed a particle experiencing
Brownian motion in a river flowing to the sea: the particle often slows its
downriver journey, and even goes upriver briefly but often, but on the whole we
will usually see that its course is down to the sea. Or will we?! It depends on
how we look. Sometimes the coin that is weighted to
show heads 99.99% of the time will come up tails tens of thousands of times in a
row, millions, billions... and just so, our particle will — on rare occasions to
be sure, but with statistical certainty — make it back upriver all the way to the
source of the Nile.
Except for the damping, these “quantinuous” Brownian changes
(in both directions) in entropy are a lot like cumulative
noise on top of the signal of the main flow of the increasing entropy of the 2nd
law. The “cumulative” is important because,
even if the Brownian changes are great, although the system may-will try to damp
them micro-viscously as they are happening, just as with standard viscosity, after they have
occurred the system will not try to “put ’em back the way they was.” (Actually, this
last will need to be questioned carefully when “Brownian entropy” is eventually
studied carefully. There might very well be quantum mechanical effects that are... paradoxical.)
But, too, we should not fail to think of chaos theory and its extravagant
exceptions to those viscosity-like damping effects.
-
Repeated for emphasis: there is an essential set of
relationships among thermodynamics, Brownian motion, entropy with its overlooked
“Brownian Entropy”, and chaos theory that
has been seriously overlooked by the scientific community.
Gedanken Experiment: Let us look at a common type of collision of idealized
particles with the same mass, but different velocities, momenta and energies.
This kind of collision is studied in physics classes, but usually in the context
of a class on mechanics. If we study it only from the standpoint of mechanics,
we do not find any problem. But if we study it from the standpoint of
thermodynamics, i.e. thinking of the 2 spheres as atoms (e.g. of helium), it is clear that it has never been
fully appreciated publicly for what it is, a counterexample to the second law of
thermodynamics and a clear statement from Mother Nature that we need to start a
new field of study: “entropodynamics”.
Figure
1a.
In
Figure 1a, we see a higher kinetic energy particle-body (body 2, with velocity
2v) approaching a lower
energy body (body 1, with velocity v).
Figure
1b.
In
Figure 1b, we see them collide like billiard balls in such a way that the center
of mass of body 2, the body with the greater kinetic energy, is in the direct line of
motion of the center of mass of body 1, the less energetic body. If body 2 had
no velocity and therefore no kinetic energy at this point, we would expect a
standard billiard ball collision that would transfer all the momentum and
kinetic energy from body 1 to body 2, leaving body 1 with a kinetic energy
corresponding roughly to “absolute zero” (if we didn’t
take into account anything else).
Figure
1c.
In Figure 1c, we see that particle-body 1 is (almost) motionless, with its
“average kinetic energy” placing it at a temperature near absolute zero (if
it were e.g. an atom of helium).
It is clear that there exist ranges of collision angles
(over 3 dimensions) that will yield anti-entropic
mechanical transfer of kinetic energy from a lower energy particle to a higher
energy particle (not to mention e.g. quantum mechanical possibilities).
These will have a lower
“cross-section” than the ranges of angles that
yield entropic exchanges, thus favoring the increase of entropy (up to the
system’s “maximum accessible entropy”), but
this still allows for the system wide sum in a given time interval to itself be
anti-entropic (especially for smaller time intervals, of course).
-
Not even the simplest model —
spherical-atomic, ideal gas laws, etc. — of the
micro-dynamics of “Brownian entropy” has ever been explicitly studied by
scientists, e.g. to the extent that kinetic energy distributions are modeled in
Maxwell’s distribution equation. How did Maxwell, Boltzmann, Gibbs, et al,
overlook the particle dynamics shown in
Figures 1a-c? How did they overlook the immediate implication that
(at least something like) Brownian entropy, with its entropy change direction
reversing “almost everywhere”, must
exist? How did they overlook that entropy does NOT truly have a tendency to
increase, but instead to spend more time in some sets of states than in others? The
answer may be that they couldn’t bring themselves to take the decidedly
Politically Incorrect stand that the 2nd
Law of Thermodynamics, which already had a sacred cow status, was... false.
Newton may have had a similar problem with the fact that
his theory predicts
that lighter and heavier bodies fall at different rates.
One of the accepted statements of the 2nd law of
thermodynamics is that
“there exists no device that can transfer
energy from a cooler body to a hotter one with no other result”,
but the above gedanken experiment disproves this:
-
There does exist a
“device that can transfer energy from a
cooler body to a hotter one with no other result”,
in violation of the 2nd law of thermodynamics:
LUCK...
(and another concept disfavored by
science: “vitalism”. Mechanism may give us
propensity, but “vitalism”
— not well-defined, to be sure — gives us essence, and I for one feel sure that we will
soon find that “vitalism” can change
those entropically preponderant probabilities and their emergent behaviors.
Although we will need to revamp our concept of Life being a local reversal of
increasing disorder-entropy, the question of the possibility of
“vitalism” re-deeming
and re-directing the emergent behaviors of mechanism is still valid. In
other words, the behaviors that emerge from mechanical systems that adapt and
become ever more complex themselves become the vehicle (in a sense reminiscent
of the
“vehicles”
we find in Buddhism: Hinayana, Mahayana, Vajrayana, etc.) Who
knows? Perhaps we will soon find that Life can make Luck as well as
Love...)
-
This study of the micro-dynamics
of “Brownian entropy” should have been, and today should be, a top priority in
physics. It is prerequisite e.g. to modeling the quantum mechanical aspects of
molecular-atomic interactions.
-
It should also be obvious that this (Figures 1abc) is a
non-equilibrium microscopic sub-situation, variants of which can and must often
take place in macroscopic equilibrium situations. (At classical equilibrium
Maxwell’s
distribution guarantees an arbitrarily wide range of molecular kinetic energies.) What is the
“temperature” at which the
“heat” energy transfer takes place?! At the
average kinetic energy of the 2 (in our case) atoms is a simple answer, but
non-equilibrium thermodynamics is not always so simple. This is a perfect point
of study for basic non-equilibrium thermodynamics that has application to
equilibrium
thermodynamics, and-or vice-versa.
-
This brings up another...
oversight relating to entropy: the usual definition of entropy has a non-zero
net flow of
heat at the equilibrium temperature of 2 bodies, and, classically, heat cannot
have a non-zero net flow of heat if there is no temperature difference. We can talk all we want to about
“infinitesimal temperature differences” and
“limiting cases”, but we are here dealing with a Gedanken Convenience Concept
that doubles as a theoretical concept. When it does so, we are in grave danger
of reasoning from false premises within our theory and therefore as part of our
theory. “That’s
a bad way to fly.”
It should be obvious from this
simple analysis that this kind of reverse entropy collision is very common. In
fact, without these law-of-entropy-violating kinetic energy transfers, Maxwell’s distribution of kinetic energies
could not be maintained since the kinetic energy of each particle would move
(erratically) toward the average and (eventually) stay there. I.e. in each 2
particle collision, the kinetic energy of each particle would have to
monotonically (but not strictly) move toward the average of the kinetic energy
of the 2 particles, inevitably reducing the highest energies toward the average,
and likewise with the lowest energies.
-
Brownian Entropy is a fundamental
underlying mechanism for the maintenance of Maxwell’s distribution of kinetic energies,
which otherwise would collapse toward the average.
-
A generalization of Brownian
Entropy will eventually be accepted as an underlying mechanism in the various
“power law” distributions, (power as in exponential, not as in work per unit
time; the value of 3/2 seems to always magically appear as an exponent, as it
does in Maxwell’s distribution equation). E.g. lower energy earthquakes are far more frequent than high energy
earthquakes, and the distribution stochastically follows a decreasing
exponential. When the micro-dynamics of earthquakes are studied more carefully,
the release and storage of the energy will be seen to undergo Brownian Entropy
style “quantinuous” reversals throughout the fault system spatially, and
throughout time as well, instead of the current concept of “continuous” buildup
to stochastically determined “continuous” release with a power law distribution
of the size of buildup before release. The usual model ignores that the buildups
and releases are stochastically overlapping in both space and time.
Digression: single collisions (as
opposed to averaged larger numbers of collisions) of atoms and molecules (as
opposed to much larger particles) are a good place to look for quantum effects
taking precedence over our simple Newtonian mechanical picture.
We can conceive of the
Brownian motion particle as being distributed through the whole volume, e.g. of
an ideal gas. (The same arguments can be extended to liquids and even solids.) When
entropy-violating collisions occur, their contributions to system entropy
are negative. If
we get enough such collisions — which, remember, instead of striking a single
larger particle as in standard Brownian motion, are distributed throughout the volume
of e.g. gas — at the “same” time, we get an entropy-violating reversal of the
entropy in the system as a whole.
Just as a standard particle is kicked around
in 3 dimensions by standard “Brownian motion”,
so our distributed particle is kicked around by our distributed “Brownian
motion”, although not always in such a way as to reverse
entropy. But the “Brownian motion” of the
distributed particle corresponds to changes in the value of the state of the
system, and these correspond to changes in its entropy, a state
function of the system, and just as with standard Brownian motion, the entropy
will be kicked into at least small excursions in the reverse direction quite
frequently (which might show up mostly as an erratic slowing of the increase of entropy if
entropy is increasing rapidly enough on the average).
So, it is highly likely that standard
analysis methods for Brownian motion can be adapted, perhaps readily, to the
study of:
the study of which, along with ergodic entropy, we can term:
as it is a thermodynamic variant
of hydrodynamics (one of many possible).
This new concept of “Brownian entropy”
suggests strongly that, just as we have
Maxwell’s equation
for the distribution of energies in an ideal gas at equilibrium, we need
to develop:
-
“entropodynamics” — a new
subfield of thermodynamics —
to
study the equilibrium and non-equilibrium
distributions of changes in
thermodynamic entropy (or perhaps a revised concept of it),
which will in general depend greatly on systemic peculiarities (in much the same way that
hydrodynamics does).
-
For example, just as the Brownian motion of a particle occurs in 3 dimensions,
we should look for the spatially distributed Brownian motion of entropy to have
higher dimensionality, i.e. for entropy to be a multi-dimensional as opposed to
a scalar state function.
The probability of a large random reversal of
entropy in an isolated system may be small in a small interval of time, but the
difference between Einsteinian and Newtonian gravity is
“small”,
too. In both cases that
“small” is
(usually) negligible to the engineer, but essential to the
scientist. Today
(at the beginning of the 21st Century),
engineering
— but not science —
can maintain the 2nd law of thermodynamics as an
approximation with suitable strictures concerning the validity of
the scope of its application, and can do so without shame. E.g., an engineer
today need not have a care to the cosmic time scale needed to produce a
reasonable probability of a cosmic scale entropic reversal. Likewise, a suitably small
thermodynamic system can cycle entropically many times a second, but today this
is still of little practical engineering significance.
So, where is this result of
“Brownian entropy” important? It is
important in any case theoretically-scientifically, and for the engineer it may be
soon that
“Brownian entropy” becomes a
pragmatic consideration in the nanoengineering that is all the rage these
days.
“Brownian entropy” is most likely
to be observed in systems with small numbers of particles, and with values
averaged over very short periods. Physicists will eventually, and
hopefully soon, try to
observe these “Brownian” entropy fluctuations experimentally and model
them in detail.
Although engineers may
not be there today in terms of needing to
engineer very small or anti-2nd law systems entropically, they will be
tomorrow. Eventually, one practical field of application for
“entropodynamics” will be the rapidly evolving science and engineering of nanotechnology, where
this non-quantum mechanical “Brownian entropy”
will likely join synergistically with quantum mechanical effects to make for “living
in interesting times”.
It should now be obvious
that, both theoretically and actually, “Brownian” fluctuations in entropy
must occur. Brownian motion is considered to be fairly well understood by
science, and is held to verify the atomic and thermodynamic nature of matter. We
have ignored the obvious implication of Brownian motion, that it is
almost a description of the microcosmic
level of the macrocosmic ergodic
actuality of thermodynamic entropy. It should be easy to begin applying the
theory of Brownian motion to any flavor of entropy (even non-physical
flavors).
“Brownian entropy” is
very important scientifically
yesterday, and it is sure to be
important for engineering in the future, but for now we can note its
inevitability and the necessary violation of the 2nd law of thermodynamics
that it entails.
Boltzmann et al to the contrary notwithstanding, the
concept of entropy has not made a successful migration from the
classical-macroscopic level of thermodynamics to the quantum atomistic-molecular (not to
mention quantum mechanical) level of our modern understanding of matter and heat. Not
at all. It was first conceived of in terms of classical (non-molecular)
“equilibrium”
thermodynamics, which meant that there was in affect only an
“infinitesimal” temperature
gradient (or whatever corresponds to that at the molecular level), and
only an
“infinitesimal”
ambiguity or vagueness in the absolute temperature
T in the expression:
Not Boltzmann nor Maxwell nor any physicist since has
even begun to sort out what should happen to our concept of entropy when
we approach the fundamental unit of entropy change, the
“elastic” (quantum theory might eventually turn that term on its head)
collision of 2 molecules (perfectly spherical, of course, so we have a
chance to make it seem like equations will do the job). No one has even
noticed that it was essential that we re-conceive entropy in these terms.
(Statistical mechanics still totally ignores the existence of Brownian
Entropy.) And this is just classical elastic collisions. Statistical
mechanics will have to be extended to quantum theory in the wave-particle
sense, not just the atomic-molecular sense, when it is extended to
“Entropodynamics”.
We can notice that, as is
invisibly common in science, the classical concept of entropy (ΔS
4 ΔQ/T)
lacks
“scalability”, so crucially important in the computer world. There it usually means
being able to take a system and get it to work without problems on a much
larger scale, but the concept works in both-all directions. (Some computer
concepts work well for large systems, but become unwieldy when trying to
use them for small systems.) The classical concept of entropy cannot be
scaled down to atomic-molecular size levels (see
Figures 1a-c), down to very small (non-averaged) time increments
and their small (non-averaged) changes in entropy, or up to very large
(non-averaged) time increments and their (again, non-averaged) changes in
entropy. We may also eventually find that it cannot be scaled up to
cosmological size levels.
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END PART 1
Entropy’s Great... Oversights
(Intro)
Entropy’s Great... Oversights, PART 1 (This
Part)
Entropy’s Great... Oversights,
PART 2
Entropy’s Great... Oversights,
PART 3
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