# Thread: Problems with classical thermodynamics

1. I was recently interested by some news that it's possible to drain energy from pure heat - absorb infrared thermal radiation:
http://www.physorg.com/news137648388.html
Other problem is for example that while spontaneous crystallization entropy goes in 'forbidden' direction:
http://www.garai-research.com/resear...py/Entropy.htm
...

It would be nice to localize simplifications of looking to be such general theory like thermodynamics.
One way of their reasons can be simplifying physics for thermodynamical model, like
- it corresponds to molecules, while we can say that their electrons live in completely different world - on a scaffolding made of molecules. Their energies doesn't correspond straightforwardly,
- thermodynamics usually ignores thermal radiation and it's energy.

But maybe there are deeper problems - thermodynamics usually ignores internal structure - for example from two states of the same energy one can be easier accesable...

What do You think about it?

2.

3. Here is simple counter example to 2nd law of thermodynamics -
converting heat into work.
Everything is in vacuum, without gravity:

Take a tube with interior covered with mirror.
Fix two transparent separators inside and place hot gas between them.
Now place two mirrors on both sides, which can freely move inside the
tube.

Some of thermal infrared photons will be bounced by a mirror - giving
part of own momentum, thanks of momentum conservation law.
The heat of the gas will be slowly converted into momentum of mirrors,
which can be converted into work.

Above example uses that despite that kinetic energy of molecules
behave randomly, each one has specific movement/oscillation, which
energy can be changed into ordered one - electromagnetic oscillation
of photon.
Thermodynamics of photons is very 'simplified' - they practically don't interact
with each other, so they don't equilibrate their energies, increase
their randomness. They also vanish when their energy goes to 0.

Are there some problems with this counter example?
The real question is if it can be used in practice - there are made
nanoantennas to catch thermal infrared:
http://www.physorg.com/news137648388.html
Can it be changed into electricity without difference of
temperatures?
The problem is with diodes which looks like Maxwell's demons...

----

If You don't like idealized unpractical models, there are also two
very practical: one for us and one for organisms which lives hundreds
of meters below and have extremely weak access to chemical energy, but
they have plenty of energy around in heat (and tectonic
vibrations...).

Both of them uses microscopic mechanisms. Usually released microscopic
energy quickly escape and change into heat. We can use that sometimes
these releases are spatially localized, so local 'mechanisms' can help
to put this energy into more stable form like potential energy of
electron in a circuit or chemical energy of some molecule (like ATP).

The first example uses that thermal infrared can not only be emitted/
absorbed by single molecules, usually using their vibrational/
rotational energy, but also for example by a free electron in a circuit
- by nanoantenna. The energy of this electron when it absorbs photon is
relatively huge - it's highly improbable that it gain this energy thanks
of thermal energy only and emit a photon - absorption will dominate
here. The problem is to rectify this electricity, but we can use that it
is highly localized. This electron will naturally equilibrate its energy
with environment, but this process is relatively slow, require some
length of way through circuit. So the nearer electron is to the antenna,
the higher average energy it statistically have.

The whole electricity generator could look like (parallel):
-conductor-threshold-antenna-conductor-threshold- and electrons should
more likely go left, because after absorbing a photon, they equilibrate
their energy while going through conductor. If the antennas are printed
as in the work of prof. Novack I've linked, required threshold could be
just narrowing/ gap.

Before going to the second example, let's think about crystallization.
It obviously increases ordering (reduce entropy), but total entropy
doesn't decrease because the binding energy (difference between energy
of the molecule in solution (larger) and after binding (smaller) ) is
stored in unstable form of energy (kinetic/vibration/rotation energy)
that quickly equilibrate its energy with environment, increasing heat/
entropy. But what if this binding energy would be stored in stable form,
like chemical energy (ATP)/conformation ? Such energy stored in ATP can
be used in order way to create work (for example using myosin). Remember
that joining to growing 'crystal' is localized reaction - could use help
of an enzyme as catalyst, which additionally stores part of binding
energy in stable form like in ATP.

The second example uses just two molecules instead of whole crystal.

Let say that we have two molecules(A,B) which has larger total energy
separated(E1) than when they are bind (E2<E1). Additionally there is
energy barrier between these states (as usual).

Now when they are bind in solution, their thermal energy statistically
sometimes exceed the barrier and they split, taking require energy from
heat -reducing temperature! But to bind them back, they not only have to
reach the barrier, but they have also to find each other in the solution
- it's not very likely, so statistically concentration of AB is
relatively small comparing to concentration of separated molecules.

Now we will need a catalyst which reduce the barrier, but then use the
energy difference for example to bind ADP and phosphate. For example it
catches all required molecules and uses just gained energy or energy
stored in own structure to take A and B closer, to make them reach the
top of the barrier, then use energy they produce to bind ADP + P and
restore own energy.

I know - this enzyme would work in both directions, but concentration of
AB should be relatively small, it doesn't have to use whole binding
energy, such that the wanted direction should dominate. Organisms can
enforce required optimal concentrations.

Returning to thermodynamics - it's derived averaging local behaviors.
It's kind of mean field approximation - forgets about correlations ...
which can give very different behaviors/interactions ... like different
stability of stored energy. I agree that it can pass simplified models
or tests like Maxwell's demon, but it's far from being proved to be
universal property.

Remember that 2nd law is not required to forbid machine which creates
work for infinity, conservation of energy/momentum already forbids it.
2nd law forbids only ordering energy stored in chaotic thermal movement.
But if this law isn't always true, there would be other counter
intuitive implications, like that computation could need no energy...
But remember that quantum computation would theoretically also offer it
- computation is invertible - doesn't use energy. Energy is required

----

I completely agree that we usually don't observe entropy reductions, but maybe it's because such reductions has usually extremely low efficiency, so they are usually just imperceptible, shadowed by general entropy increase... ?

2nd law is statistical mathematical property of model with assumed physics.
But it was proven for extremely simplified models!
And still for such simplified models was used approximation - while introducing functions like pressure, temperature we automatically forget about microscopic correlations - it's mean field approximation.
Maybe these ignored small scale interactions could be use to reduce entropy...
For example thermodynamics assumes that energy quickly equilibrate with environment ... but we have eg.ATP, which stores own energy in much more stable form then surrounding molecules, be converted into work...

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