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Questions on Thermodynamic Free Energy.


JohnSSM

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I am looking to fully grasp the concept of what "free energy" means in terms of thermodynamic systems.  I understand why free energy is the amount of work that any system can perform, which represents an amount energy itself.  But I dont understand the stipulation of "at a constant temperature".  

And what this mean for equilibrium vs non equilibrium thermodynamics.  I was hoping for a real world example of a system using equilibrium thermodynamic and non equilibrium thermodynamics.

I understand that if you put a sealed plastic bag, full of water at 80 degrees, into a tank of water at 60 degrees, that thermodynamic equilibrium will cause the heat energy from the plastic bag of warm water, to transfer into the cooler water, until they are both the same temperature.  IS that equilibrium or non equilibrium thermodynamics?  And what is an example of the other?

And how could we begin to define or estimate how much free energy the 80 degree water has.  And it seems to be, I remember reading that Feynman describes how there is always just a bit more free energy available, than the work that needs to be done, and it doesnt make much sense to me.

Any info in understanding free energy?

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41 minutes ago, JohnSSM said:

I am looking to fully grasp the concept of what "free energy" means in terms of thermodynamic systems.  I understand why free energy is the amount of work that any system can perform, which represents an amount energy itself.  But I dont understand the stipulation of "at a constant temperature".  

 

In order to do a calculation there are variables you need to hold constant. Otherwise you'll never have enough information to solve a problem — too many variables.

 

41 minutes ago, JohnSSM said:



And what this mean for equilibrium vs non equilibrium thermodynamics.  I was hoping for a real world example of a system using equilibrium thermodynamic and non equilibrium thermodynamics.

I understand that if you put a sealed plastic bag, full of water at 80 degrees, into a tank of water at 60 degrees, that thermodynamic equilibrium will cause the heat energy from the plastic bag of warm water, to transfer into the cooler water, until they are both the same temperature.  IS that equilibrium or non equilibrium thermodynamics?  And what is an example of the other?

The end states are equilibrium. 

Sometimes the path you take to get there matters. Other times it doesn't matter.

 

41 minutes ago, JohnSSM said:

And how could we begin to define or estimate how much free energy the 80 degree water has.  And it seems to be, I remember reading that Feynman describes how there is always just a bit more free energy available, than the work that needs to be done, and it doesnt make much sense to me.

Any info in understanding free energy?

Which free energy? Gibbs or Helmholtz? (again, it's a matter of which variables are held constant, and which change value)

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Im not sure how to directly reply to anyone, but this is in reply to Swansont.

I should explain myself further.  With a small theoretical knowledge of many different subjects in physics, I am a psychological writer. 

Carl Friston has a psychiatry based theory of free energy, which he adopted from the theories of thermodynamic free energy.  I have read the wikipedia on thermodyamic free energy, and have many clues to understanding it, but with conceptual thinking only.  Theoretical understandings are all I need to grasp, just so I can grasp how the free energy concept applies to neurology and the very way our own brains seek order, and part of that order is saving energy while creating negentropy.  Friston uses the concepts from thermodynamic free energy, to model how our brains evolved.  He combines elements from Bayesian models of probability, the Markov blanket, along with entropy and negentropy.  I understand Bayes, The concept named after Markov, and i think I understand entropy and negentropy.  What I still dont get is free energy and what it is based on. It sounds like potential energy to me, but there seems to be a difference. 

As I understand it, Feynman developed this free energy model in thermodynamics, trying to figure out the probability of the path any election might take, and how heat transfers from one system to another.  So, Ive looked very far into the topic, but can only skim the surface of all the concepts behind it, and just need a way to rationalize it so I can use that understanding and that model it in my own thoughts.  I know it's a very different approach than a quantified scientist takes, but I have to approach it only to model these laws in neurological behavior, not understand their truest nature.  But, I may be in the wrong place.  Ha...I do appreciate your answers, but have no real base of knowledge to respond, which is why I chose to include some examples and then asked for other real world examples.  

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30 minutes ago, JohnSSM said:

Carl Friston has a psychiatry based theory of free energy, which he adopted from the theories of thermodynamic free energy. 

Then I’m guessing there’s not a rigorous mapping between them, so “energy not used/wasted on other things, so it’s available to do work” probably suffices

 

 

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Not a rigorous mapping, indeed.  It is the difference between non-equilibrium and equilibrium systems.  

"The free energy principle is a formal statement that explains how living and non-living systems remain in non-equilibrium steady-states by restricting themselves to a limited number of states.[1] It establishes that systems minimise a free energy function of their internal states, which entail beliefs about hidden states in their environment. The implicit minimisation of free energy is formally related to variational Bayesian methods and was originally introduced by Karl Friston as an explanation for embodied perception in neuroscience,[2] where it is also known as active inference."

I dont understand a NON-EQUILIBRIUM steady state.  

I think I do understand now.  I thought that non-equilibrium thermodynamics was the opposite of equilibrium thermodynamics, when it actually seems to be a category of, which involves the transfer of energy to achieve equilibrium.  

But I like to nail down an example so I can accurately describe it to others who wont have the physics background to get it.

I came up with the water capsule in a water tank.  IF the capsule and the tank both hold the same amount of water, and the tank is at 50 degrees and the capsule water is at 60 degrees, if we can assume an uninterupted transfer of heat, or path to equilibrium, eventually all the water in the tank and capsule would be 55 degrees if all the water didnt lose any heat energy anywhere else.  A closed system is what they call this?  Being exposed to each other, the closed systems have to account for the state of the other, and the capsule loses its heat energy to the tank water, and they become one system with its own equilibrium state again.  AM I showing how equilibrium works, is a law of physics and describing the process of non-equilibrium states brought together?   Could one say, in very simple terms, that the water capsule had to give the tank water, 5 degrees of heat energy?  Just for conceptual purposes in the frame of this example?

The psychological question becomes, how many folks perceived a worth in spending their energy to read this topic, or answer it.  Their perception of me would greatly effect that decision.  The truth is, my question presents a problem.  Some folks may pass on answering it because they don't have the free energy to deal with it, but physics says they do.  Me having a question and you having answer presents a loss of equilibrium between us.  In physics, you would not have the CHOICE but to answer my question, as the water has no choice in losing it's heat to a cooler system, but it may take hours or days for all the heat to find an equilibrium, and it may take hours or days to try to answer my question.  Humans are presented with nonequilibrium constantly, but having free will, as opposed to non a biological system with feelings and emotions to ultimately guide them against the order that nature must follow.  Nature expects your knowledge to flow into me, if I have a lack of that knowledge.  But you hav a choice in enabling that flow, and that's why this is soooo amazing to me.  

IF there is a riot, the amount of people who join in will depend on how they value their own free energy, and how they choose to use it.  This theory will be huge in sociology.  That's my bet.  So thanks for the attention!  Any further explanations of the process involved in thermodynamic equilibrium and free energy would be great.  The mapping between the two subjects of physics and neurology and psychology has not been maximized.   SO any info I get, can help me to maximize the mapping between the 2. 

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22 hours ago, JohnSSM said:

I am looking to fully grasp the concept of what "free energy" means in terms of thermodynamic systems.  I understand why free energy is the amount of work that any system can perform, which represents an amount energy itself.  But I dont understand the stipulation of "at a constant temperature".  

And what this mean for equilibrium vs non equilibrium thermodynamics.  I was hoping for a real world example of a system using equilibrium thermodynamic and non equilibrium thermodynamics.

I understand that if you put a sealed plastic bag, full of water at 80 degrees, into a tank of water at 60 degrees, that thermodynamic equilibrium will cause the heat energy from the plastic bag of warm water, to transfer into the cooler water, until they are both the same temperature.  IS that equilibrium or non equilibrium thermodynamics?  And what is an example of the other?

And how could we begin to define or estimate how much free energy the 80 degree water has.  And it seems to be, I remember reading that Feynman describes how there is always just a bit more free energy available, than the work that needs to be done, and it doesnt make much sense to me.

Any info in understanding free energy?

Ignore any references to thermodynamic work for now - it's irrelevant to what you're trying to get your head around.

The stipulation "at a constant temperature" simply implies that transitions between significantly different temperatures require multiple calculations over small temperature changes (ie. integration wrt temperature)

Free energy values, especially for water, can easily be obtained from thermodynamic tables or calculated from standard values. But your interest is more in changes in free energy.

Consider the process of water freezing. At high temperatures the free energy of liquid water is higher than the free energy of ice. The freezing of water is associated with a negative change in free energy and is therefore disallowed whereas ice will melt spontaneously. At low temperatures the reverse is true. At around 273 K the free energies are equal and so the changes in free energy for both the freezing and melting processes are zero. This defines thermodynamic equilibrium: there is no nett tendency for more water to freeze nor more ice to melt. 

Having established that principle, we can now look at a slightly more complex process that is (I think!) relevant to your main interest.

Let us take our liquid water at (or at least close to) freezing point and expose it to a large departure from equilibrium via a significant source of negentropy: a sealed, insulated vacuum chamber

The change in free energy for the transition liquid water to water vapour is positive, and so the liquid starts to boil. But this chills the water, making the transition of water to ice positive also, so we get simultaneous freezing. Eventually the vapour pressure reaches 611 Pa and the free energy of vapourisation falls to zero. As does the free energy of condensation, the free energy of melting, the free energy of freezing and incidentally, the free energies of both sublimation (ice to vapour) and deposition (vapour to ice). Thermodynamic equilibrium is reached at the triple point.

But the key point to take home is that by adding a medium entropy material (cold water) to a substantial source of negentropy (the vacuum chamber) we've managed to create a relatively low entropy state (ice) without recourse to external energy input. This simple experiment belies the idea that thermodynamics cannot create ordered systems spontaneously. Given a large enough departure from equilibrium and a good mix of building blocks to play with, structures of arbitrary levels of complexity are not only possible, but inevitable. Even brain matter!     

 

Edited by sethoflagos
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23 hours ago, JohnSSM said:

I am looking to fully grasp the concept of what "free energy" means in terms of thermodynamic systems.

First and foremost swansont has already noted that Free Energy can mean different things in thermodynamics.

Quote

Britannica

https://www.britannica.com/science/free-energy

Free energy, in thermodynamics, energy-like property or state function of a system in thermodynamic equilibrium. Free energy has the dimensions of energy, and its value is determined by the state of the system and not by its history. Free energy is used to determine how systems change and how much work they can produce. It is expressed in two forms: the Helmholtz free energy F, sometimes called the work function, and the Gibbs free energy G. If U is the internal energy of a system, PV the pressure-volume product, and TS the temperature-entropy product (T being the temperature above absolute zero), then F = UTS and G = U + PVTS. The latter equation can also be written in the form G = HTS, where H = U + PV is the enthalpy. Free energy is an extensive property, meaning that its magnitude depends on the amount of a substance in a given thermodynamic state.

 

Now in relation to available work, there is also a quantity known as the 'maximum work function' which is identified with the Helmholtz free energy.

So the situation is rather complicated .

 

In general we have processes that occur at constant temperature or at constant pressure (you can't have both at once)

Gibbs free energy occurs at constant temperature

Helmholtz free energy occurs at constant pressure

 

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2 hours ago, sethoflagos said:

Ignore any references to thermodynamic work for now - it's irrelevant to what you're trying to get your head around.

The stipulation "at a constant temperature" simply implies that transitions between significantly different temperatures require multiple calculations over small temperature changes (ie. integration wrt temperature)

Free energy values, especially for water, can easily be obtained from thermodynamic tables or calculated from standard values. But your interest is more in changes in free energy.

Consider the process of water freezing. At high temperatures the free energy of liquid water is higher than the free energy of ice. The freezing of water is associated with a negative change in free energy and is therefore disallowed whereas ice will melt spontaneously. At low temperatures the reverse is true. At around 273 K the free energies are equal and so the changes in free energy for both the freezing and melting processes are zero. This defines thermodynamic equilibrium: there is no nett tendency for more water to freeze nor more ice to melt. 

Having established that principle, we can now look at a slightly more complex process that is (I think!) relevant to your main interest.

Let us take our liquid water at (or at least close to) freezing point and expose it to a large departure from equilibrium via a significant source of negentropy: a sealed, insulated vacuum chamber

The change in free energy for the transition liquid water to water vapour is positive, and so the liquid starts to boil. But this chills the water, making the transition of water to ice positive also, so we get simultaneous freezing. Eventually the vapour pressure reaches 611 Pa and the free energy of vapourisation falls to zero. As does the free energy of condensation, the free energy of melting, the free energy of freezing and incidentally, the free energies of both sublimation (ice to vapour) and deposition (vapour to ice). Thermodynamic equilibrium is reached at the triple point.

But the key point to take home is that by adding a medium entropy material (cold water) to a substantial source of negentropy (the vacuum chamber) we've managed to create a relatively low entropy state (ice) without recourse to external energy input. This simple experiment belies the idea that thermodynamics cannot create ordered systems spontaneously. Given a large enough departure from equilibrium and a good mix of building blocks to play with, structures of arbitrary levels of complexity are not only possible, but inevitable. Even brain matter!     

 

Thank you.  Yes, given enough departure from equilibrium, it did create biological life.  The point being, human evolution was just another step of universal evolution.  And so are stars, as they are what is needed to create heavier elements through fusion, and those heavier elements is what it needed to create life.  And what event started all this departing from equilibrium?  The start of the universe.  IF you consider that the big bang is real in some way, do you believe it had ultimate order and perfect equilibrium before the bang?  The bang happened, and now the four forces are attempting to re-order the huge loss of equilibrium?  I dont need a theory that can convince physicists, as it is a book about the brain and psychology, but i dont want the theory to be physical impossible...afterall, it did happen.

1 hour ago, studiot said:

First and foremost swansont has already noted that Free Energy can mean different things in thermodynamics.

 

Now in relation to available work, there is also a quantity known as the 'maximum work function' which is identified with the Helmholtz free energy.

So the situation is rather complicated .

 

In general we have processes that occur at constant temperature or at constant pressure (you can't have both at once)

Gibbs free energy occurs at constant temperature

Helmholtz free energy occurs at constant pressure

 

Now I do understand the difference between the Gibbs and Hemholtz approaches. So a Gibbs system must use pressure to drive the system and the Hemlholtz system is using heat.  No sweat. Ha

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23 minutes ago, JohnSSM said:

And what event started all this departing from equilibrium?  The start of the universe.  IF you consider that the big bang is real in some way, do you believe it had ultimate order and perfect equilibrium before the bang?  The bang happened, and now the four forces are attempting to re-order the huge loss of equilibrium? 

The CMBR map tells us that the early universe was extremely close to thermal equilibrium (and in a relatively low entropy state) at least until recombination. 

Significant departure from equilibrium began with the ensuing localised gravitational collapses and formation of the first stars. Only then did we have the large thermal and density gradients that are necessary to drive far-from-equilibrium processes.

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  • 2 weeks later...

In my studies of the early universe, the four forces of the universe could only take action once the universe had cooled substantially.  This could be seen as a period of less entropy, while reaching thermal equilibrium.  And it was only because of the cooling, and the forces of the universe that simple atoms could gather into objects massive enough to create the gravity needed to bring on another stage of entropy, in nuclear fusion.   So it seems the universe switched from a period of low entropy before the big bag, to a period of high entropy, after the big, which led to inflation, cooling and a period of lowering entropy to create solid matter, which actually creates more entropy, and gravities' influence can finally take hold, taking away entropy as it orders matter together, and then gravity reaches the other side of entropy as it allows for fusion and the creation of even more molecules, which increases entropy, but allows for yet, more order, as those compounds mix together with more possibilities of entropy, introduced by water, gases, heat, friction, light, and we get living systems from a non living system, who all experience their time as survival in terms of order and entropy.

Do you see every stage of the universe only in terms of the continuation of a gain or a loss of entropy?  Or do you see this back and forth evolution as I tried to describe?  

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20 minutes ago, JohnSSM said:

Do you see every stage of the universe only in terms of the continuation of a gain or a loss of entropy?  Or do you see this back and forth evolution as I tried to describe?  

 

No

Entropy is a state function.

To apply the laws and structure of Thermodynamics you must first establish the state or states to have a state function.

To establish the state (if any) you must establish the nature of the system (Universe)

We do not know if the system is closed, open or isolated so cannot apply the Laws.

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Sure, entropy is a function of states, and a loss of heat always creates a correlation in a loss of entropy.  But it didn't take a heating to create the the first clumps of matter that grew into stars that burst into nuclear fusion due to gravity.  It took a cooling, or a loss of heat, after an initial heating.  

Im not applying the laws and structure of thermodynamics, Im applying a model of thermodynamics.    To apply the laws, I would need to establish a state function for the universe as it cooled, then I would need a state function that created the heat within stars from fusion.

I know that entropy is about more than heat and could apply to many forms of energy, if not all. 

So we cant make a statement that the universe was losing entropy as it cooled after inflation?  And that nuclear fusion didnt increase entropy to create heavier elements with more possibilities?

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10 minutes ago, JohnSSM said:

Sure, entropy is a function of states, and a loss of heat always creates a correlation in a loss of entropy.  But it didn't take a heating to create the the first clumps of matter that grew into stars that burst into nuclear fusion due to gravity.  It took a cooling, or a loss of heat, after an initial heating.  

Im not applying the laws and structure of thermodynamics, Im applying a model of thermodynamics.    To apply the laws, I would need to establish a state function for the universe as it cooled, then I would need a state function that created the heat within stars from fusion.

I know that entropy is about more than heat and could apply to many forms of energy, if not all. 

So we cant make a statement that the universe was losing entropy as it cooled after inflation?  And that nuclear fusion didnt increase entropy to create heavier elements with more possibilities?

This has nothing to do with my point.

We don't know if the Universe is an open or closed or isolated system.

This is so basic that it must be addressed to make any statement about gain or loss of entropy or any other thermodynamic property.

Until anyone can answer this they are just building castles in the air.

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On 3/14/2021 at 7:58 AM, JohnSSM said:

  The point being, human evolution was just another step of universal evolution.  And so are stars, as they are what is needed to create heavier elements through fusion, and those heavier elements is what it needed to create life.  And what event started all this departing from equilibrium?  The start of the universe.  IF you consider that the big bang is real in some way, do you believe it had ultimate order and perfect equilibrium before the bang?  The bang happened, and now the four forces are attempting to re-order the huge loss of equilibrium?  I dont need a theory that can convince physicists, as it is a book about the brain and psychology, but i dont want the theory to be physical impossible...afterall, it did happen.

Having not really run into you before, let me clarifiy, that I am no professional or expert for that matter, just a poor old retired maintenance Fitter/Machinist/Welder.

The BB is our model of universal/space/time evolution, ( from t+10-45 seconds) and it is supported by the four main pillars of cosmology. (abundance of lighter elements, CMBR, reversal of observed expansion, and galactic formation)

In that first instant post BB it was so hot, that the four forces were all united/combined into what has been called the "Superforce": As temperatures and pressures dropped, the superforce started to decouple, gravity first. This created phase transitions and false vacuums, and the excesses of energy went into creating our first fundamental particles. At three minutes post BB, conditions were such that the first atomic nuclei formed, protons/Neutrons. It took another 380,000 years for conditions to be such that electrons were able to be captured by the atomic nuclei and our first light elements were formed....H  and He. From there gravity worked its magic and Abiogeneis and voila!! here we are!

Let me add an important point as follows.....

8 minutes ago, studiot said:

We don't know if the Universe is an open or closed or isolated system.

This is so basic that it must be addressed to make any statement about gain or loss of entropy or any other thermodynamic property.

Until anyone can answer this they are just building castles in the air.

 

Edited by beecee
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42 minutes ago, studiot said:

This has nothing to do with my point.

We don't know if the Universe is an open or closed or isolated system.

This is so basic that it must be addressed to make any statement about gain or loss of entropy or any other thermodynamic property.

Until anyone can answer this they are just building castles in the air.

I was building off of something that sethoflagos said, and I had also thought before.

"The CMBR map tells us that the early universe was extremely close to thermal equilibrium (and in a relatively low entropy state) at least until recombination."

I suppose he must be making an assumption about the state of the universe before the big bang.  He assumes, and so did I, that the pre-big bang universe has very little entropy.  This leads to the belief that the big bang represented a huge shift in universal entropy, from low entropy to much entropy.  

Are we both making a subjective assumption about the true state of entropy that no one really knows?  

In that first instant post BB it was so hot, that the four forces were all united/combined into what has been called the "Superforce": As temperatures and pressures dropped, the superforce started to decouple, gravity first. This created phase transitions and false vacuums, and the excesses of energy went into creating our first fundamental particles. At three minutes post BB, conditions were such that the first atomic nuclei formed, protons/Neutrons. It took another 380,000 years for conditions to be such that electrons were able to be captured by the atomic nuclei and our first light elements were formed....H  and He. From there gravity worked its magic and Abiogeneis and voila!! here we are!

I wouldnt see them as combined, I would see them as equally ineffective in their mission to bring order back.  The energy of the big bang could not be instantly contained by the forces that were working to keep them at a low entropy state before the big bang.  It seems, if the four forces were always there, holding us in a state of low to no entropy, until something triggered this huge and dramatic change of entropy, called the big bang, doesn't it make sense that the four forces were now working to bring all that energy back to a low entropy state?  Don't forces by their very nature present an order and in that, an opposition to high entropy states? But, in this process of regaining order, entropy must go through an evolution of low entropy states to high entropy states.  IF we plotted the low entropy state of the universe at big bang to the different entropy states it experiences to regain order through the four forces, wouldn't we see a wave overtime in entropy itself?

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38 minutes ago, JohnSSM said:

I wouldnt see them as combined, I would see them as equally ineffective in their mission to bring order back.  The energy of the big bang could not be instantly contained by the forces that were working to keep them at a low entropy state before the big bang.  It seems, if the four forces were always there, holding us in a state of low to no entropy, until something triggered this huge and dramatic change of entropy, called the big bang, doesn't it make sense that the four forces were now working to bring all that energy back to a low entropy state?  Don't forces by their very nature present an order and in that, an opposition to high entropy states? But, in this process of regaining order, entropy must go through an evolution of low entropy states to high entropy states.  IF we plotted the low entropy state of the universe at big bang to the different entropy states it experiences to regain order through the four forces, wouldn't we see a wave overtime in entropy itself?

Hi John... just hit the "quote' function in the bottom left hand corner, next to the plus.

Aren't we working towards a theory of everything, by combining all the forces? In other words getting back to conditions post BB? aka a superforce? Don't we already see electricity and magnetism as electromagnetism?

Another important point, the BB should not be seen as an explosion, rather just an evolution. And again, we can't talk with any confidence about any before the BB.

Edited by beecee
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1 minute ago, beecee said:

Hi John... just hit the "quote'function in the bottom left hand corner, next to the plus.

Aren't we working towards a theory of everything, by combining all the forces? In other words getting back to conditions post BB? aka a superforce? Don't we already see electricity and magnetism as electromagnetism?

Another important point, the BB should not be seen as an explosion, rather just an evolution. And again, we can't talk with any confidence about any before the BB.

Yes.  I am a psychological researcher, and developed my own ideas of living systems, evolving from an already existing non-living system, based on the fundamental reactions of the four forces and all the laws they create.   The existence of heat can only be a function of those four forces in a certain state, so thermal dynamics isn't a fundamental force in the universe, but it does behave in accordance with the four forces and it does create a new subset of laws that direct how heat acts.  But it's not just heat, it's all energy.  Neither is entropy a fundamental force of the universe, but still creates realities and laws that dictate it.  Biological life and evolution use the same doctrines created along the way, and so do our brains. So psychology and personality disorders, and psychiatry and neurology all use the same doctrines as well.  It is a theory of every process which creates all the systems of the universe.  Living systems evolved to give the universe subjectivity.  We now interpret rules and make rules to deal with our senses. Psychology as a system developed to bring order to thoughts, using the tenants of saving free energy, minimizing entropy and surprise, to simply endure or survive.  So yes, a theory of everything.

Doesnt that fact that magnets lose their electromagnetic drives to order, when exposed to high heat, mean anything to this perspective?  Isnt heat always entropic in nature?  I suppose if the goal is creating ash from leaves, then heat could be seen as ordered to that goal.  But doesnt it take high entropy to turn a leaf into ash?  Is there any perspective which claims, the ash from leaves is more ordered than the leaf itself?  Does the requirement of adding energy to the properties of the leaf in an oxygen environment show that energy is needed for entropy as it adds entropic possibilities to create ash?  IS there no strict determination of a loss or gain in entropy? It's always relative when you dont know the nature of your own system?

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11 hours ago, JohnSSM said:

In that first instant post BB it was so hot, that the four forces were all united/combined into what has been called the "Superforce": As temperatures and pressures dropped, the superforce started to decouple, gravity first. This created phase transitions and false vacuums, and the excesses of energy went into creating our first fundamental particles.

Thermodynamics is indifferent to whether there are four or four hundred or four thousand 'forces' acting or available.
In short it is not about forces.

11 hours ago, JohnSSM said:

In that first instant post BB it was so hot, that the four forces were all united/combined into what has been called the "Superforce": As temperatures and pressures dropped, the superforce started to decouple, gravity first. This created phase transitions and false vacuums, and the excesses of energy went into creating our first fundamental particles. At three minutes post BB, conditions were such that the first atomic nuclei formed, protons/Neutrons. It took another 380,000 years for conditions to be such that electrons were able to be captured by the atomic nuclei and our first light elements were formed....H  and He. From there gravity worked its magic and Abiogeneis and voila!! here we are!

Thermodynamics is also indifferent to time.

Where in Thermodynamics is there any definition of a second or that your three minutes are the same as my three minutes ?

Another basic fact about Thermodynamics is that it discusses thermodynamic equilibrium and the direction the evolution of a system can take, but not the time it takes for this to happen.

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15 hours ago, JohnSSM said:

Do you see every stage of the universe only in terms of the continuation of a gain or a loss of entropy?  Or do you see this back and forth evolution as I tried to describe?  

I'm no expert on cosmology, far from it, but the general picture I have is of periods of free expansion (which I presume to be near isentropic) punctuated by intermittent phase changes (eg  quarks 'condensing' into hadrons, nucleosynthesis etc) as and when the temperature falls to to the point where the free energy change for that transition becomes positive. 

At each phase change, we see the matter components of the universe transform into a more structured lower entropy state, accompanied by a large release of energy (the associated 'latent' heat for that phase change) into the surrounding 'photon gas', the radiative component of the universe. The overall process may well approximate to a period of expansion at constant temperature with a corresponding significant overall entropy increase.

As regards the influence of your four fundamental forces on entropy, I guess it depends on whether those forces are attractive or repulsive in nature. Attractive forces tend to create structure, so I suppose you could view them as battling with entropy in some sense. But the repulsive forces do quite the opposite. I'm not sure that alloting a 'purpose' to these forces is helpful to a true understanding of them.

 

Edited by sethoflagos
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4 hours ago, studiot said:

Thermodynamics is indifferent to whether there are four or four hundred or four thousand 'forces' acting or available.
In short it is not about forces.

Thermodynamics is also indifferent to time.

Where in Thermodynamics is there any definition of a second or that your three minutes are the same as my three minutes ?

Another basic fact about Thermodynamics is that it discusses thermodynamic equilibrium and the direction the evolution of a system can take, but not the time it takes for this to happen.

If thermodynamics is not an original force of the universe, then it is a force created by the four forces, which makes it a factor of those forces.  The only reason thermodynamics has dynamics to study, which create laws, is because of the four forces, not because of heat or dynamics.  Heat and dynamics only exist because of the four forces. Time is not a force of the universe either.  IF there were forces that acted independently of the four forces, then there would be a fifth and sixth force, but there arent.  So my observation is simple and obvious.  

3 hours ago, sethoflagos said:

 

As regards the influence of your four fundamental forces on entropy, I guess it depends on whether those forces are attractive or repulsive in nature. Attractive forces tend to create structure, so I suppose you could view them as battling with entropy in some sense. But the repulsive forces do quite the opposite. I'm not sure that alloting a 'purpose' to these forces is helpful to a true understanding of them.

 

Which repulsive force is that?  It's not gravity or the strong nuclear force. Electromagnetism is not repulsive anymore than it is attractive and the weak force is also not repulsive.

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33 minutes ago, JohnSSM said:

If thermodynamics is not an original force of the universe, then it is a force created by the four forces, which makes it a factor of those forces. 

Thermodynamics isn't a force

A lot of thermodynamics relationships involve energy, because there are systems where you either know energy is conserved, or can track the energy entering and leaving the system.

 

33 minutes ago, JohnSSM said:

The only reason thermodynamics has dynamics to study, which create laws, is because of the four forces, not because of heat or dynamics.  Heat and dynamics only exist because of the four forces.

That's true, but not particularly relevant.

Physics boils down to what problems you can solve, and since energy is a conserved quantity, that's one of the useful quantities to track.

 

 

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3 hours ago, sethoflagos said:

I'm no expert on cosmology, far from it, but the general picture I have is of periods of free expansion (which I presume to be near isentropic) punctuated by intermittent phase changes (eg  quarks 'condensing' into hadrons, nucleosynthesis etc) as and when the temperature falls to to the point where the free energy change for that transition became positive. 

At each phase change, we see the matter components of the universe transform into a more structured lower entropy state, accompanied by a large release of energy (the associated 'latent' heat for that phase change) into the surrounding 'photon gas', the radiative component of the universe. The overall process may well approximate to a period of expansion at constant temperature with a corresponding significant overall entropy increase.

As regards the influence of your four fundamental forces on entropy, I guess it denpends on whether those forces are attractive or repulsive in nature. Attractive forces tend to create structure, so I suppose you could view them as battling with entropy in some sense. But the repulsive forces do quite the opposite. I'm not sure that alloting a 'purpose' to these forces is helpful to a true understanding of them.

 

 

No expert on cosmology maybe, but a wise and well considered post nonetheless.

+1

25 minutes ago, JohnSSM said:

If thermodynamics is not an original force of the universe, then it is a force created by the four forces, which makes it a factor of those forces.  The only reason thermodynamics has dynamics to study, which create laws, is because of the four forces, not because of heat or dynamics.  Heat and dynamics only exist because of the four forces. Time is not a force of the universe either.  IF there were forces that acted independently of the four forces, then there would be a fifth and sixth force, but there arent.  So my observation is simple and obvious.  

 

This nonsense of pure speculation is a far cry for someone who started of asking the question.

 

On 3/12/2021 at 7:41 PM, JohnSSM said:

I am looking to fully grasp the concept of what "free energy" means in terms of thermodynamic systems. 

 

Thermodynamics is not a 'force'. Period.

Congratualtions you have successfully hijacked your own thread.

 

For your information models, views or interpretations of  Physics that are based on the force concept are usually called Newtonian and most of the subject falls under the purview of Mechanics.

There are however alternative models, viewpoints or interpretations that do not use a force concept at all.

These may be derived from Newtonian and/or relativistic mechanics or the energy methods of Lagrange, Hamilton, Mach, and others.

Or they may be represented by the Mathematics of 'forms'  - forms in particular.

Or again they may be represented by the calculus of variations.

These latter methods have the advantage that they also mean something in both relativistic mechanics and quantum theory.

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10 minutes ago, studiot said:

 

No expert on cosmology maybe, but a wise and well considered post nonetheless.

+1

 

This nonsense of pure speculation is a far cry for someone who started of asking the question.

 

 

Thermodynamics is not a 'force'. Period.

Congratualtions you have successfully hijacked your own thread.

 

For your information models, views or interpretations of  Physics that are based on the force concept are usually called Newtonian and most of the subject falls under the purview of Mechanics.

There are however alternative models, viewpoints or interpretations that do not use a force concept at all.

These may be derived from Newtonian and/or relativistic mechanics or the energy methods of Lagrange, Hamilton, Mach, and others.

Or they may be represented by the Mathematics of 'forms'  - forms in particular.

Or again they may be represented by the calculus of variations.

These latter methods have the advantage that they also mean something in both relativistic mechanics and quantum theory.

I find it amazing that you get frustrated to the point of seeming offended because I make points from perspectives that do not please you.  At this point i'm just following a conversation. This was my reply to you and you didnt address any of it.  Do you just ignore the into you dont like during communication?  That will never be a model for good communication and im wondering if that is your goal here at all.  

"I was building off of something that sethoflagos said, and I had also thought before.

"The CMBR map tells us that the early universe was extremely close to thermal equilibrium (and in a relatively low entropy state) at least until recombination."

I suppose he must be making an assumption about the state of the universe before the big bang.  He assumes, and so did I, that the pre-big bang universe has very little entropy.  This leads to the belief that the big bang represented a huge shift in universal entropy, from low entropy to much entropy.  

Are we both making a subjective assumption about the true state of entropy that no one really knows?  "

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36 minutes ago, JohnSSM said:

 

Which repulsive force is that?  It's not gravity or the strong nuclear force. Electromagnetism is not repulsive anymore than it is attractive and the weak force is also not repulsive.

 The strong force at distances oto 0.7 fm? Proton-proton electrostatic repulsion? Others .....

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29 minutes ago, swansont said:

Thermodynamics isn't a force

A lot of thermodynamics relationships involve energy, because there are systems where you either know energy is conserved, or can track the energy entering and leaving the system.

 

That's true, but not particularly relevant.

Physics boils down to what problems you can solve, and since energy is a conserved quantity, that's one of the useful quantities to track.

 

 

I never said that thermodynamics was a force, so I'm not sure why you're pointing it out to me.

I was simply trying to make a point that every dynamic, law, or rule in physics, or in the world, all come from one source, which is the combined expressions of the four forces.

IN following the conversation you would see that studiot said 
"Thermodynamics is indifferent to whether there are four or four hundred or four thousand 'forces' acting or available.
In short it is not about forces."

I was pointing out how wrong this perspective is.  The only reason there is thermodynamics is because of the four forces.  He's right, it doesnt matter how many there are, which was never my point, my point is that we know there are four.  So it's not important at all, I was explaining reality to studiot.

11 minutes ago, sethoflagos said:

 The strong force at distances oto 0.7 fm? Proton-proton electrostatic repulsion? Others .....

They named it the strong force because of it's strong force of holding quarks, protons, nuetrons, etc together.  It is not named for it's repulsive tendencies, so I do see your point, but mine is more obvious.  

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