The second law is generally considered as a dissipative law, whereas, many evolution processes show that order could arise spontaneously, in my opinion, the second law itself contains the mechanism of evolution.
In the fundamental equation of the second law,
diS=ΣdiSj ≥0,
here diS is the total entropy production, and diSj is the partial differential of diS in process j.
The equation does not require each of diSj≥0, it only requires that the total entropy production is positive definite, but the partial differentials of which can be less than zero. In the case diSj=k
Dear Tang Suye
This is an interesting topic, and one that I have been pondering for a long time. Here are a few thoughts.
The second law describes the direction of all physical processes that I can think of. This includes thermal conduction (Fourier's law), electrical conduction (Ohm's law), fluid flow with a pressure gradient, chemical reaction, a body falling from height to the ground, and I am sure many more. In all cases we create circumstances in which the second law can run its course, taking the system (universe) from a less probable state (lower entropy) to a more probable state (higher entropy). This seems reasonable, since the universe is made up of randomly moving and vibrating atoms and molecules.
The one physical phenomenon I am unable to explain with the second law is the origin of life. The formation of complex organic molecules would go from a more likely state to a less likely state. This can only happen spontaneously, if the reactions are exothermic. In this case they would most likely be endothermic. The net change in entropy would therefore be negative, and the change not spontaneous. Work would have to be involved.
All the best
Johan
Excluding biology, all physical evolutions are governed by the second law of thermodynamics. But, life birth and its function suggest that second law of thermodynamics can be violated. If we could bring its violation under our control, it will be a new long lasting world.
Dear Johan,
Consider a chemical reaction, -ΔG/T≥0 (ΔG≤0), the changes in the system involve the two items, one is the change in the internal energy, another one is the change in the molecular structure, the first item relates to calorimetric entropy, the Gibbs free energy to be converted into the energy of thermal motion, I call as heat energy, in such case, we have the calorimetric entropy production diST≥0, and, the second item relates to configuration entropy, in general, in the case ΔG≤0, the configuration entropy production diSv can be less than zero, the equation of the total entropy production
diS=diST+diSv≥0.
In which, we have diST≥0, and diSv≤0.
Best regards,
Tang Suye
Yesterday I occasionally deleted my long answer to this question. Briefly.
The second law of thermodynamics is valid only for isolated systems. The Earth is not the isolated system. The origin of life does not violate the second law. Chemical reactions commonly proceed with a decrease of entropy. A reaction might proceed spontaneously if the change in free Gibb's energy is negative. If the reaction is thermodynamically favorable, this does mean that the reaction will proceed. The reaction rates rae controlled not only by thermodynamics but also by kinetics. All living organisms (as well as all organized systems) are thermodynaically unstable but stable kinetically.
Tang Suye My friendly advise. Learn chemical thermodynamics instead of writing such out of ordinary text:
"Consider a chemical reaction, -ΔG/T≥0 (ΔG≤0), the changes in the system involve the two items, one is the change in the internal energy, another one is the change in the molecular structure, the first item relates to calorimetric entropy,"
Dear Tang Suye
I am starting to see your perspective better. You are looking at a single spontaneous change A (your chemical reaction), and the ΔS of A can be divided into two parts, namely heat and configuration. I agree with you there, it is possible that parts of the entropy change can be negative, as long as the total change is positive.
The ΔS that the second law refers to is the change in entropy of the universe as result of A, which includes ΔSsurroundings an ΔSsystem. If the sum of all the different entropy changes inside your system is negative, the ΔSsurroundings term must be positive to the extent that their sum is positive. Then we can have spontaneous change. Otherwise we have to do some work to get what we need.
Kind regards
Johan
Dear Yurii,
a) The classical equation of the second law is derived from the efficiency of heat engine, it is expressed as the increment in the entropy of an isolated system dS ≥ 0, however, in non-equilibrium thermodynamics, the increment in the entropy of an isolated system has been substituted by the entropy production diS and the inequality diS ≥ 0 [1], the second law (the inequality diS ≥ 0 ) has already been extend to open system.
b) I agree with The origin of life does not contradict the second law. However, this is not only the question of the chemical stability, one want to know the thermodynamic mechanism that how the order and life arise spontaneously, and, does the mechanism/direction of evolution has already been contained in the second law itself?
Thanks for your friendly advise, I had learned chemical thermodynamics in many years ago, I must confess, I have forgotten many contents.
[1] I.Prigogine Science. 201 4358 (1978)
Best regards,
Tang Suye
I don't think that it's worth to apply non-equilibrium thermodynamics to explain chemical processes. The classical thermodynamics and chemical kinetics works very well.
What statement is the Second Law ? : the entropy production is not negative !
This statement is true for discrete systems and for a field formulation of thermodynamics, but not valid for special processes in Stochastic Thermodynamics. The connection between entropy and entropy production is as follows: entropy production is defined as the entropy change in isolated systems. Thus in open systems, the entropy time rate may be negative, but the entropy production is not nagative. Some references can be found in the attached papers.
Dear Muschik,
The statement of the second law: for all of thermodynamic system, and for all of thermodynamic processes, the total entropy production
diS≥0
but the partial differentials of diS can be greater, less than or equal to zero.
I suggest you to verify the statement ''but the partial differentials of diS can be greater, less than or equal to zero.'' For example, an ideal gas doing work.
Best regards,
Tang Suye
In thermodynamic processes, the partial differential of the total entropy production less than zero is a common phenomenon, such as a non-spontaneous reaction or phase transition, graphite → diamond (Ji-Tao Wang). In the inequality diS≥0, the partial differentials of the total entropy production are more easy to be distinguished than in the inequality dS≥0.
My conclusion for this topic can be seen in [1], p9.
[1]Preprint Heat Energy, Entropy and The Second Law: A New Perspective i...
The deviation rate of the second law of thermodynamics is 14.6%. See the following figure (or annex). It's not a case.
* * * * * * * *
A: Figure 1 is from the authoritative book "Handbook for Estimating Gas-liquid Physical Properties", which calculates enthalpy change H1 by equation of state. From Fig. 1A, the accuracy of the equation of state is very high, but the enthalpy deviation rate derived is very large. The theoretical basis of the derivation is the thermal 2 differential equation.
B. Drawing with the deviation rate of state equation (< 1%) and enthalpy variation deviation rate (Fig. 2), without considering two abnormal points, the deviation rate is regularly arranged. The deviation rate of fitting line and Y axis intersection point C (0,0.146) and thermal 2 differential equation is 14.6%.
1. Here, "propane 300K, 0.99MPa state" is a very general state.
2. We choose the deviation rate of the equation of state - 1%~+1%, which is very accurate.
3. The enthalpy deviation rate corresponding to zero of the equation of state is 14.6% by fitting line. This is caused by the second law of thermodynamics.
Logical error of the second law of thermodynamics:
1. There are many kinds of type 2 perpetual motion machines. Behind each type is a natural phenomenon.
Machine A: against the irreversibility of thermodynamics (diffusion, heat conduction, friction, etc) - dynamics;
Machine B: Utilizing the Difference of Carnot Efficiency (Reversible Thermodynamics) - Thermodynamics
2. A and B belong to different disciplines. There is a parallel relationship between them, and there is no logical mutual inevitability.
Heat 2 Logic: Experience induction, deny that A machine==》 B machine can not be manufactured==》 All material Kano efficiency: 1-T1/T2.
3. Logical of the second law of thermodynamics violates the physical logic that A and B cannot be inferred from each other.
4. the second law of thermodynamics elevates the "irreversibility", but it is only a kinetic experience.
5. See the annex for details.
1. I am discussing how to deduce Kano efficiency = 1-/T1/T2 from "irreversibility".
2. You are repeatedly emphasizing the importance of "irreversibility" and "dissipation". It's not something I'm stressing.
3. The logic of the second law of thermodynamics, which is the content of the textbook, comes from the papers of Kelvin and Clausius.
××××××××××××××××
Logical error of the second law of thermodynamics:
1. There are many kinds of type 2 perpetual motion machines. Behind each type is a natural phenomenon.
Machine A: against the irreversibility of thermodynamics (diffusion, heat conduction, friction, etc) - dynamics;
Machine B: Utilizing the Difference of Carnot Efficiency (Reversible Thermodynamics) - Thermodynamics
2. A and B belong to different disciplines. There is a parallel relationship between them, and there is no logical mutual inevitability.
Heat 2 Logic: Experience induction, deny that A machine==》 B machine can not be manufactured==》 All material Kano efficiency: 1-T1/T2.
3. Logical of the second law of thermodynamics violates the physical logic that A and B cannot be inferred from each other.
4. the second law of thermodynamics elevates the "irreversibility", but it is only a kinetic experience.
I just started a new discussion: Can Second law of Thermodynamics be abandoned?
Wouldn’t it be an interesting idea to explore the possibility that the troubled second law of thermodynamics can be cancelled, completely?
https://www.researchgate.net/post/Can_Second_law_of_Thermodynamics_be_abandoned
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