[Malamute Lover (OP)]

Why is the Second Law of Thermodynamics (SLOT) time asymmetric? 

Why is it that the hot coffee gets cooler instead of hotter or just staying the same? With the exception of SLOT, the laws of Physics are time symmetric. Run the time parameter backward and you will reproduce the past conditions.  Why is the Second Law of Thermodynamics uni-directional? Because, we are told, of the Arrow of Time. Things develop in one direction in time. Why is that? Because of the Second … um, what was the question?

Why is SLOT different from other laws of Physics? Why the time asymmetry?

The coffee cools off over time, an obvious fact. How come it was hot in the first place? It got heated on the stove, via some kind of energy, gas or electricity or whatever. Where did that energy come from? Ultimately from the sun, or if it is nuclear then it resulted from a supernova that created the uranium. Why are there stars? Why do they put out energy? Planets, galaxies, dust clouds – where did they come from? None of this came fully formed with the Big Bang.

The answer is Gravity of course. And Gravity is always ‘down’, so to speak. It ‘pulls’ instead of ‘pushing’. The asymmetry is still there if you phrase it in General Relativity theory instead of Newtonian mechanics. The coffee cools because it was made hot by energy that ultimately derives from gravity. Local entropy can decrease such as stars forming and starting to shine or a cup of coffee getting heated as long as overall entropy increases. That is all that SLOT requires.

But why is gravity asymmetric in time? Gravitational force is related to the mass of the gravitating bodies. Which leads to the simple idea that gravity being ‘down’ results from the mass sign being positive. And guess what? If we look around at the universe, we notice that all of the mass is positive. There is no negative mass. All of the other physical properties – charge, spin etc. – exist in positive and negative forms. Why not mass?

If mass had a negative sign, gravity would be ‘up’ instead of ‘down’. Entropy would decrease instead of increasing. Now flip your point of view and you will see that a negative mass universe would work the same as ours just backward in time. Of course the inhabitants of such a universe would think of their SLOT (TOLS?) in terms of entropy increasing just like we do. They would imagine us as the ones going backward in time.

The direction of the Arrow of Time, in which overall entropy increases, appears to be related to all mass in a universe having the same sign. Whether it is labeled positive or negative does not matter, as long as it is all the same. That allows SLOT to be a universal unbreakable law, in terms of overall entropy increasing.

OK but why is mass always the same sign? Perhaps at the origin of the universe, whatever that might be like, both positive and negative mass arose in equal proportions. If the shape of space-time is related to the sign of mass (and isn’t it?) maybe all the positive mass went one way in time and all the negative mass went the other way. In this (very definitely hypothetical) scenario, there would be a pair of universes, mass-positive and mass-negative, both originating from the origin. Notice that the sum of the masses in the two universes is zero. No net excess of mass to explain.

[Kryptid]

If mass had a negative sign, gravity would be ‘up’ instead of ‘down’. Entropy would decrease instead of increasing.

I'm skeptical of that. Say that you have a box filled with negative mass particles. The particles all start off in the center of the box clustered together. This cluster is in a state of high gravitational potential energy, and could therefore be used to do useful work if we put some kind of device in it in order to take advantage of it. But as that cluster expands (due to the gravitational repulsion of its components), the particles fill up the box like a gas. Now there is no longer a gravitational potential gradient and the available gravitational potential energy is gone (having been converted into kinetic energy). Now our device can no longer extract as much (or possibly any) useful energy to do work. The expansion of the cluster has caused the entropy in the box to go up.

[Malamute Lover (OP)]

If mass had a negative sign, gravity would be ‘up’ instead of ‘down’. Entropy would decrease instead of increasing.

I'm skeptical of that. Say that you have a box filled with negative mass particles. The particles all start off in the center of the box clustered together. This cluster is in a state of high gravitational potential energy, and could therefore be used to do useful work if we put some kind of device in it in order to take advantage of it. But as that cluster expands (due to the gravitational repulsion of its components), the particles fill up the box like a gas. Now there is no longer a gravitational potential gradient and the available gravitational potential energy is gone (having been converted into kinetic energy). Now our device can no longer extract as much (or possibly any) useful energy to do work. The expansion of the cluster has caused the entropy in the box to go up.

Thank you for the reply!

I assume you mean that this box of negative mass particles is in our positive mass universe, not my hypothetical negative mass universe and that any positive/negative references we make are from our ‘clock goes clockwise’ point of view. Let us ignore the fact that in the real world any such experimental setup would be embedded in a gravitational field from some other source and any other irrelevant intervening variables. The only gravitational (or other) forces that need to be discussed are those related to the particles themselves.

To begin with, gravitational potential energy can only be made useful if it is converted into some other form of energy. An egg held (gently) in the hand will not break unless it is dropped. The gravitational potential energy is converted into kinetic energy, which is expended when the egg hits the floor breaking the shell.  The bigger the drop, the more resulting kinetic energy.

The gravitational potential energy of positive mass particles when such particles not clustered is negative. That is, the gravitational field pulls instead of pushing. (If they are clustered, they cannot fall any further no matter what and the gravitational potential energy is zero.)  The gravitational potential energy of clustered negative mass particles is positive. It pushes instead of pulling. The negative mass particles fly apart instead of sticking together.

The negative mass particles flying apart have negative kinetic energy. An expanding cloud of positive mass particles, maybe blown apart by a firecracker, could be a source of positive energy. Extracting and storing their kinetic energy would slow them down. Their kinetic energy would go in a negative direction. However, negative mass energy particles would have negative kinetic energy. Any method of extracting positive kinetic energy from them, making it go in a negative direction (even if this were possible) would speed them up. Extracting negative kinetic energy, heading up toward zero, would require inputting positive energy.

The gravitational potential energy of a positive mass particle at an arbitrarily great distance from a gravitating source of positive mass is arbitrarily large on the positive side. (The gravitating mass could be the effective center of a cluster of positive mass particles.) It can fall very far and be going really fast when it hits because it is getting pulled more and more.  The greater the distance, the greater the kinetic energy and the more work that could theoretically be done. The local net energy level increases. Decreasing entropy. This is how gravity can create regions of low entropy,


The gravitational potential energy of a negative mass particle at an arbitrarily great distance from a gravitating source of negative mass is arbitrarily large on the negative side. (The gravitating mass could be the effective center of a cluster of negative mass particles.) It continues to be pushed and therefore goes faster, even though the pushing force is decreasing. Less and less work can be done since the kinetic energy of the negative mass particle is getting more negative, the further away it gets. The local net energy decreases. Increased entropy.

When comparable situations are examined, the resulting entropy situations are seen to be opposite when positive mass and negative mass are examined.

[Kryptid]

The negative mass particles flying apart have negative kinetic energy. An expanding cloud of positive mass particles, maybe blown apart by a firecracker, could be a source of positive energy. Extracting and storing their kinetic energy would slow them down. Their kinetic energy would go in a negative direction. However, negative mass energy particles would have negative kinetic energy. Any method of extracting positive kinetic energy from them, making it go in a negative direction (even if this were possible) would speed them up. Extracting negative kinetic energy, heading up toward zero, would require inputting positive energy.

This is a good point. I have often thought about negative mass/energy, but sometimes forget about the nitty gritty of the way it works. I suppose if you define everything from a negative energy standpoint, available energy increases over time as it approaches zero instead of decreasing.

[puppypower]

Why is it that the hot coffee gets cooler instead of hotter or just staying the same? With the exception of SLOT, the laws of Physics are time symmetric. Run the time parameter backward and you will reproduce the past conditions.  Why is the Second Law of Thermodynamics uni-directional? Because, we are told, of the Arrow of Time. Things develop in one direction in time. Why is that? Because of the Second … um, what was the question?

For entropy to increase, it needs to absorb energy. Since the second law states that the entropy of the universe has to net increase, the energy being absorbed into entropy is being made net unusable to the universe.

The energy is conserved within the entropy, but entropy by having to always net increase renders  an ever increasing amount of energy non recyclable and not reusable. 

If we have a mother cell, splitting into two daughter cells, the system entropy has increased; more complex state. This more complex state has absorbed some energy into the higher entropy state, which now cannot be easily reused. The two daughter cells cannot go backwards unless we add extra energy beyond what was needed to go forward.

Energy conservation applies, however the energy that goes into entropy is stuck in limbo, and is no longer a part of the useable energy of the universe; as we go forward in time.

Entropy can be reversed. We can freeze and thaw water and ice. But this requires we add some extra energy to makeup for the loss due to the original entropy increase. I tend too believe the limbo energy, within universal entropy, is what we call dark energy. However, I think we are reversing cause and affect, since most appear to assume only reversible energy, but not the existence of energy, that results in complexity, being stuck in limbo.

If the universe reached a state of infinite entropy, there would be no useable energy in the universe. To an outsider, our universe would appear to have zero energy. However, the blue print of creation; all the entropy states facades, would still theoretically, exist due to energy conservation. The ancients would call this the alpha and the omega.

If you were God, or could play the role of God in the movies, to form a new universe from the zero energy void, you would need to figure out a way to lower entropy to release its hidden energy. One would have to brood over the blue print, in the cold darkness, until light appear from the void.

I use the term blue print because entropy is a state variable, meaning for a given state of matter, the entropy is a fixed value that is alway the same. Water at 25C and one atmosphere has a fixed entropy value that is used as a standard. The facade of matter; states, is like a blue print.

[evan_au]

If mass had a negative sign.... Entropy would decrease instead of increasing.

The problem is that mass has a corresponding energy, and even if the gravitational mass were negative, the equivalent energy would still be positive.

Whether antimatter has a different gravitational attraction than "normal" matter has still not been resolved.
- This is the subject of ongoing experiments at CERN (eg ALPHA)
See: https://en.wikipedia.org/wiki/Gravitational_interaction_of_antimatter

Looking to the future, entropy would still increase even with repulsive mass, because the statistical distribution of matter would become more uniform in an (accelerating) expanding universe.

Peering into the past, there is one event that may have caused more differentiation on our universe, and that is the hypothetical splitting of the 4 fundamental forces, as posited by string theory (and others).
See: https://en.wikipedia.org/wiki/Grand_Unified_Theory

[Malamute Lover (OP)]

For entropy to increase, it needs to absorb energy. Since the second law states that the entropy of the universe has to net increase, the energy being absorbed into entropy is being made net unusable to the universe.

SLOT actually says that the overall entropy of an isolated system tends to increase over time. There is no physical reason why the combination of forces might not result in all the air molecules in a room to simultaneously be in the lower half of the room, resulting in a temperature increase. It is just outrageously improbable unless some special circumstances were invoked.  (Freezing all the air and having it settle to the floor would be a good start.)

Entropy is a useful mathematical tool, founded on statistics. It is not a physical thing. Usable energy is not absorbed into entropy. The energy goes some place in the physical world.

The energy is conserved within the entropy, but entropy by having to always net increase renders an ever increasing amount of energy non recyclable and not reusable. 

Whether energy is useable depends on circumstances. In the winter a hot cup of coffee can be used to warm your hands. Energy is leaving the coffee and warming your hands (and other areas of the environment such as the air). Entropy in the cup is increasing. Put the cup in a pan of hot water the same temperature as the coffee and there is no net energy flow. Entropy in the cup remains the same. Heat the water more and the entropy in the cup is decreasing as energy flows into it. Take the cup out of the water and it now does an even better job of warning your hands because it has more useable energy than before.

If we have a mother cell, splitting into two daughter cells, the system entropy has increased; more complex state. This more complex state has absorbed some energy into the higher entropy state, which now cannot be easily reused. The two daughter cells cannot go backwards unless we add extra energy beyond what was needed to go forward.

Life can be metaphorically characterized as an entropy exporting system. It depends on external energy sources of the right type to keep increasing entropy at bay and stay alive. In time the feedback systems that keep something alive fail and the organism dies. Left to itself, it will return to the raw components that constitute it. Entropy has increased.

For daughter cells to go back to a single mother cell would require not just an input of energy but a radical and careful restructuring of the feedback systems that resulted in the binary fission in the first place. Since this would involve some kind of chemical processes, presumably it would require energy to accomplish. But for the daughter cells to keep on doing what they normally do also requires energy input. All we are saying here is that life requires useable energy.

Energy conservation applies, however the energy that goes into entropy is stuck in limbo, and is no longer a part of the useable energy of the universe; as we go forward in time.

Entropy can be reversed. We can freeze and thaw water and ice. But this requires we add some extra energy to make up for the loss due to the original entropy increase. I tend to believe the limbo energy, within universal entropy, is what we call dark energy. However, I think we are reversing cause and effect, since most appear to assume only reversible energy, but not the existence of energy, that results in complexity, being stuck in limbo.

First, a note on terms. Entropy is a calculable value that can increase of decrease in the local system of interest depending on circumstances. The value of entropy can be changed one way or the other. But entropy is not a physical thing.

As I noted earlier, energy does not go into limbo. In most circumstances, it is merely dispersed into less useable forms. Entropy is statistical and abstract, not physical and real.  Energy that is not useable in one circumstance might become useable in another circumstance. Hot coffee in a thermos is in thermodynamic equilibrium. High entropy. It cannot be used for anything as long as it remains in the thermos. Pour it into a cup and it can warm your hands and your insides. Low entropy but increasing.

Dark energy is the hypothetical entity that is partly responsible for the expansion of the universe. It is doing work. It cannot be in a state of maximum entropy.

If the universe reached a state of infinite entropy, there would be no useable energy in the universe. To an outsider, our universe would appear to have zero energy. However, the blue print of creation; all the entropy states facades, would still theoretically, exist due to energy conservation. The ancients would call this the alpha and the omega.

A better phrase would be ‘maximum entropy’. The term ‘infinite’ can be confusing. Zero useable energy is not the same as zero energy. Mass is equivalent to energy and as long as matter exists there will be energy. Not just in the abstract but in reality. Gravitating bodies will still exert pressure inside them being resisted by electron shell repulsion. Once in equilibrium the energy will no longer be useable but it is still there as long as there is gravity.

If you were God, or could play the role of God in the movies, to form a new universe from the zero energy void, you would need to figure out a way to lower entropy to release its hidden energy. One would have to brood over the blue print, in the cold darkness, until light appear from the void.

I use the term blue print because entropy is a state variable, meaning for a given state of matter, the entropy is a fixed value that is alway the same. Water at 25C and one atmosphere has a fixed entropy value that is used as a standard. The facade of matter; states, is like a blue print.

If I were playing God in a movie I would make the universe two-sided, one side with positive mass and the other side with negative mass. No net mass to have to invent.  The entropy related arrow of time would arise naturally.

The ‘fixed entropy value’ is arbitrary for convenience. It is not any sort of absolute value. And unless you are talking about fundamental particles, entropy is always a ratio, not an absolute value. Entropy was originally defined in this manner because nobody knew just how big or small the hypothetical atoms were.

BTW Water at 0.01° C at 1 atm is the standard, not 25° C. In engineering related to the thermodynamics of water (e.g., heating systems), this is the arbitrary zero value of entropy by definition because it is very handy mathematically to do it that way. 0C would be a problem because water can exist in solid or liquid state at that temperature, which would require talking about enthalpy. In this type of engineering, entropy is only defined up to just under 374° C because that is the limit of superheating, above which water will become steam regardless of pressure because the strength of the hydrogen bonds will be overcome.

I refuse to discuss enthalpy because (a) although I learned about it in school, I never used it in real life and it is now as opaque to me as the Latin I learned, and (b) I do not want engineering students asking me their homework questions. I understand someone pulled that stunt a while back. No replies naturally.

[Malamute Lover (OP)]

If mass had a negative sign.... Entropy would decrease instead of increasing.

The problem is that mass has a corresponding energy, and even if the gravitational mass were negative, the equivalent energy would still be positive.

Whether antimatter has a different gravitational attraction than "normal" matter has still not been resolved.
- This is the subject of ongoing experiments at CERN (eg ALPHA)
See: https://en.wikipedia.org/wiki/Gravitational_interaction_of_antimatter

Looking to the future, entropy would still increase even with repulsive mass, because the statistical distribution of matter would become more uniform in an (accelerating) expanding universe.

Peering into the past, there is one event that may have caused more differentiation on our universe, and that is the hypothetical splitting of the 4 fundamental forces, as posited by string theory (and others).
See: https://en.wikipedia.org/wiki/Grand_Unified_Theory

E = mc^2
If m is negative, energy is negative

Since the shape of spacetime is determined by mass-energy and since antimatter definitely has positive mass – otherwise the mass energy balances in collider events would be out of whack – I see no reason to imagine that antimatter would fall ‘up’.  But experimental physicists with big expensive toys gotta play. And sometimes with surprising results.

The only ‘experimental’ evidence so far is the essentially simultaneous arrival of neutrinos and antineutrinos from the 1987 supernova. Considering the distance that they traveled (164,000 light years) there should have been some difference in arrival times if they experienced different gravitational interactions, and therefore different paths, along the way.

The further apart positive mass objects are, the higher (more positive) the gravitational potential energy. As discussed earlier in this thread, the further apart negative mass objects are, the lower (more negative) the gravitational potential energy.

In addition, the heat death of the universe would not result from the dispersion of material by expansion but from using up sources of available energy such as in stars. This would be the case even if the universe were not expanding. Stars form and operate because positive masses attract. The excess binding energy in atoms lighter than iron is gradually used up as heavier and heavier elements are formed in the stars, increasing entropy. Recall that a black hole, the ultimate fate a star might achieve, is in a state of maximum possible entropy for its size.

By not shedding the excess binding energy in the fusion furnaces of stars, the entropy of negative mass matter remains low.

[puppypower]

SLOT actually says that the overall entropy of an isolated system tends to increase over time. There is no physical reason why the combination of forces might not result in all the air molecules in a room to simultaneously be in the lower half of the room, resulting in a temperature increase. It is just outrageously improbable unless some special circumstances were invoked.  (Freezing all the air and having it settle to the floor would be a good start.)

This is true, but since there is no such thing as perpetual motion, this very action will net increase entropy, even though we have reversed entropy somewhere else. There is always a net loss of useable energy, via the second law, from the universe.

Matter or antimatter both stem from and contain energy, while gravity and anti-gravity are both part of energy conservation with neither having full access to the energy that is lost to entropy. When gravity acts entropy can reverse but they extra energy came from the potential energy within the gravitational potential. As gravity gets stronger due to less size, work cause heat energy, which then starts to increase entropy again to form other states of matter.

The term entropy was originally coined by engineers who were developing the first steam engines. They would measure the energy into and the work and energy out of their engines, and noticed that they could not close the energy balance. There was missing energy. This loss of energy was measurable and repeatable, Entropy was mathematically defined as the difference. The statistical explanation for the how and why of entropy came later, when statistics came into vogue. It does not explain the missing energy. Missing energy loads the dice.

In terms of modern chemistry, entropy is considered a state variable, meaning for any given state of matter, such as a one liter of water at 25C and 1 atmosphere, it has a specific amount of entropy. This is repeatable and can be achieved by any path to the final state.

The relationship between any given state; specific set of conditions for matter, and the fixed amount of entropy, makes entropy connected to the facades or blue prints of materials. Whether it be matter or antimatter, both are types of facade, and each defines a given amount of entropy, along with other forms of internal energy; enthalpy.

Our universe is mostly matter with a minor amount of antimatter. There is a time asymmetry here also.  We currently assume this is based on randomness; roll the dice. Or we might  assume this is due to each state having different amounts of entropy; energy in limbo. Both can have the same free energy; equal and opposite, but differences in entropy facade would create differences in enthalpy so free energy is the same. Antimatter appears to contain more enthalpy, to make it more active in the world of available energy. Matter does better in the world of unavailable energy and facades.

An interesting application of entropy is the living state. There is no other state in the universe with as many layers of facade, at all levels. Life is high in entropy and full of limbo energy that can be reverse as needed, since we constantly eat and metabolize to create the extra energy needed to satisfy the second law, while being able to reverse states.

The foundation of the entropy of life is within water and hydrogen bonding. The hydrogen bond has both polar and covalent bonding character. A hydrogen bond can form and then can go both ways with only a minimal change in free energy. The polar state has higher measurable entropy while the covalent state has lower entropy. Water and hydrogen bonds can switch back and forth since there is available thermal and metabolic energy, to make up the difference imposed by the second law.

The DNA, also uses hydrogen bonding as part of its template activity. The second law will drive evolution on the template, by altering polar and covalent patterns in previous states. Higher entropy means a more complex facade and more limbo energy. Evolution is not random but is based on the second law. Life will not spontaneous; reform the dinosaurs. Humans may do this in the lab, but it will have a large energy cost to recreate a lower entropy state.

[Malamute Lover (OP)]

SLOT actually says that the overall entropy of an isolated system tends to increase over time. There is no physical reason why the combination of forces might not result in all the air molecules in a room to simultaneously be in the lower half of the room, resulting in a temperature increase. It is just outrageously improbable unless some special circumstances were invoked.  (Freezing all the air and having it settle to the floor would be a good start.)

This is true, but since there is no such thing as perpetual motion, this very action will net increase entropy, even though we have reversed entropy somewhere else. There is always a net loss of useable energy, via the second law, from the universe.

My point was that SLOT is based on statistical considerations. The fewer the particles that are involved, the less absolute SLOT becomes. In everyday circumstances, the number of particles involved is always so enormously high that minor exceptions to a strict application of the law are not going to get noticed. Consider a dozen or so particles somewhere within a cup of coffee. The combination of external kinetic forces acting on this small cluster of particles could result in them very briefly reaching a temperature equal to that of the surface of the sun even if ice cold a split instant before. In fact, statistics tells us that things like this probably happen all the time somewhere within the cup. On the large scale, in a system that is hotter than its environment, heat energy is ‘always’ being lost to the environment, the odds against anything else happening being so preposterously high. 

Matter or antimatter both stem from and contain energy, while gravity and anti-gravity are both part of energy conservation with neither having full access to the energy that is lost to entropy. When gravity acts entropy can reverse but they extra energy came from the potential energy within the gravitational potential. As gravity gets stronger due to less size, work cause heat energy, which then starts to increase entropy again to form other states of matter.

Anti-gravity? Antimatter has positive mass just like normal matter, as confirmed by innumerable particle collider data points. There is no reason to think that anti-gravity is involved.  My discussions on hypothetical negative mass matter did not involve antimatter.

While the kinetic energy of gravitational collapse is what kickstarts stars into shining, it is the release of excess binding energy in less massive atoms that keeps them going. The high temperature and density at the core facilitate atomic fusion, liberating energy. If it were not for the untapped binding energy, stars would slowly cool and compress to their maximum density and it would be a much more boring universe.

The term entropy was originally coined by engineers who were developing the first steam engines. They would measure the energy into and the work and energy out of their engines, and noticed that they could not close the energy balance. There was missing energy. This loss of energy was measurable and repeatable, Entropy was mathematically defined as the difference. The statistical explanation for the how and why of entropy came later, when statistics came into vogue. It does not explain the missing energy. Missing energy loads the dice.

Carnot first stated the principles that would eventually lead to SLOT but dealt only with the concept of heat without consideration of any possible ensemble of particles. His work concerned the maximum efficiency of heat powered engines, recognizing that there will always be lost energy. Clausius made the idea of heat more rigorous and moved further toward SLOT but still without involving particles. It was Clausius who invented the term ‘entropy’ to represent the loss of useable energy in a system. Boltzmann introduced the particle notion and the statistical approach to thermodynamics, despite the idea of atoms not being widely accepted at the time.  (1) Lots of other names between and after that point.

There is no missing energy, Energy does not disappear. It can change to different forms not all of which are useful to us. The exhaust from a car engine is (just about) useless for propelling the car but it is still hot. Energy is conserved. BTW to understand why that is always the case, one need not go beyond the two-hundred-year old Carnot Cycle model.

(1) Ernst Mach, brilliant 19th century physicist but radical logical positivist, insisted that no one should even be allowed to talk about atoms because it would never be possible to observe them directly. Anything that could not in principle be observed did not exist. Mach was something of a mentor to Einstein but ironically Einstein’s work on the statistical basis of Brownian motion led to a more rigorous theory of atoms and a substantial proof that they really existed. The year I was born an atom (carbon) was visualized for the first time via X-ray interferometry. I was a practicing professional before some clever engineers at a large corporation spelled out IBM with atoms, visible through an electron microscope. I recall reading years back (but cannot recall all the details) about raising a single atom to a sufficient excitation state that it could be seen glowing with the naked eye. It was never a question of size but of brightness, just like with stars.

In terms of modern chemistry, entropy is considered a state variable, meaning for any given state of matter, such as a one liter of water at 25C and 1 atmosphere, it has a specific amount of entropy. This is repeatable and can be achieved by any path to the final state.

I have no idea what you mean by “This is repeatable and can be achieved by any path to the final state.”

I see that 25 ° C (‘room temperature’) is the reference point in chemistry for entropy values of different substances. Thermodynamic engineering involving water uses the 0.01° C standard. The two values are not comparable even when using the same dimensional terms. Entropy is powerful conceptual entity, but not a physical one.

The relationship between any given state; specific set of conditions for matter, and the fixed amount of entropy, makes entropy connected to the facades or blue prints of materials. Whether it be matter or antimatter, both are types of facade, and each defines a given amount of entropy, along with other forms of internal energy; enthalpy.

Entropy is not energy. Enthalpy involves energy of specific types, although it is not identical to energy, as you said.

Otherwise, I do not understand what you are saying.

Our universe is mostly matter with a minor amount of antimatter. There is a time asymmetry here also.  We currently assume this is based on randomness; roll the dice. Or we might assume this is due to each state having different amounts of entropy; energy in limbo. Both can have the same free energy; equal and opposite, but differences in entropy facade would create differences in enthalpy so free energy is the same. Antimatter appears to contain more enthalpy, to make it more active in the world of available energy. Matter does better in the world of unavailable energy and facades.

My proposal put forth in my original post is that the time asymmetry we observe in physical processes is due to the universe being composed of positive mass. Matter and antimatter are not really related to this. I imagine that negative mass matter would also have normal matter and antimatter states, each appearing in equal proportions in high (negative) energy interactions. Whether the unexpected preponderance of normal matter over antimatter is somehow related to my double universe idea I could not say. However, CPT violations may give a clue, an idea I have yet to wrap my mind around.

But going back to what you said – why should antimatter have greater enthalpy?

An interesting application of entropy is the living state. There is no other state in the universe with as many layers of facade, at all levels. Life is high in entropy and full of limbo energy that can be reverse as needed, since we constantly eat and metabolize to create the extra energy needed to satisfy the second law, while being able to reverse states.

Life exists because it maintains a state of low entropy, maintaining organization and energy level differential with the environment.  High entropy would mean low values for useable energy. That describes a rock, not a living entity.

The foundation of the entropy of life is within water and hydrogen bonding. The hydrogen bond has both polar and covalent bonding character. A hydrogen bond can form and then can go both ways with only a minimal change in free energy. The polar state has higher measurable entropy while the covalent state has lower entropy. Water and hydrogen bonds can switch back and forth since there is available thermal and metabolic energy, to make up the difference imposed by the second law.

While water is important to life because if its ability to dissolve, suspend and transport, the real hero is carbon. It’s enormous capability for making compounds, including extremely large and complex ones, and the large energy potentials that these compounds can contain is what makes complicated life forms possible. A rarely appreciated characteristic of carbon is that the byproduct of energy producing reactions (carbon dioxide) is a gas, allowing ready disposal. By contrast, carbon’s only competitor – silicon – has less compound forming capability, less energy potentials and its byproduct, silicon dioxide, is an inconvenient solid.

But we are getting outside the bounds of this sub-forum.

The DNA, also uses hydrogen bonding as part of its template activity. The second law will drive evolution on the template, by altering polar and covalent patterns in previous states. Higher entropy means a more complex facade and more limbo energy. Evolution is not random but is based on the second law. Life will not spontaneous; reform the dinosaurs. Humans may do this in the lab, but it will have a large energy cost to recreate a lower entropy state.

The ultra-complexity of DNA is due to its heritage, billions of years of energy input in an environment favorable to trial and error, combined with a titanic amount of that trial and error over the ages. The entropy increase in the universe at large that was involved in all that is truly colossal compared to the even the mind-boggling organization level of DNA.

But again, wrong place

[puppypower]

While water is important to life because if its ability to dissolve, suspend and transport, the real hero is carbon. It’s enormous capability for making compounds, including extremely large and complex ones, and the large energy potentials that these compounds can contain is what makes complicated life forms possible. A rarely appreciated characteristic of carbon is that the byproduct of energy producing reactions (carbon dioxide) is a gas, allowing ready disposal. By contrast, carbon’s only competitor – silicon – has less compound forming capability, less energy potentials and its byproduct, silicon dioxide, is an inconvenient solid.

Experiments were done where cells were dehydrated and then the water was replaced by a wide range of other solvents, to see what would happen to the organic compounds of life. This was connected to the theory life can appear in other solvents.

The results were, nothing worked properly, in any other solvent, down to individual enzymes. The carbon compounds became lifeless and lacked useful function without water. Wheh water was added everything worked and life appeared. What is often attributed in life, to statistics, is actually logically explained by the co-partnership with water.

Life, as we know it, evolved in water. Water was/is the micro environment for natural selection at the nanoscale from day one. If we placed life in the Arctic region or the Amazon Jungles, each environment will set parameters that life will need to meet. Life will need to stay warm in the Arctic and say cool in the Amazon; environmental pressures that have a predetermine result. Water had potential needs and life has to conform.

The DNA was selected by the water environment. DNA would not have been selected in any other solvent. If life had evolved in alcohols or any other solvent, which there is no proof it can, other organic or silicon chemicals would need to selected, since the experiments shows that the organic chemicals selected by water, for life, do not work in these solvents.

Entropy is connected to free energy by the equation G=H-TS, where G is the Gibbs free energy, H is enthalpy, T is temperature and S is entropy.

The second laws says that the S of the universe has to increase. The increase in S lowers the free energy G due to the minus sign in the equation. As universal entropy net increases, to obey the second law, the free energy of the universe gets less and less. There is less net free energy, that is usable to the universe, as time moves forward.

The universe was originally very hot so the T term or temperature was extreme. The early universe was making free energy unusable at a very high rate. Stars and fusion and extreme heat continue this tradition. There is less universal free energy, in play today, than there was yesterday.

What we call time, moves in the direction of diminishing useable free energy. Entropy and time share the feature of moving in one net direction; forward. Entropy has to increase and time has to move forward. The net loss of useable energy creates a moving target in time.

What has screwed up science, are the clocks that we use to measure time. Clocks cycle which is not how time behaves. This is how energy and waves behave, but not time. Clocks are the wrong analogy for time since they model time as a waves even though time only moves in one direction.

This is like using a thermometer to measure length. It can be done with some ingenuity; expansivity, However, this will  perpetuate a practical misconception that time is somehow connected to energy waves.  Free energy is TS and S does not cycle. Clocks do a better measuring TS,  since TS is a measure of energy.

[Malamute Lover (OP)]

Experiments were done where cells were dehydrated and then the water was replaced by a wide range of other solvents, to see what would happen to the organic compounds of life. This was connected to the theory life can appear in other solvents.

The results were, nothing worked properly, in any other solvent, down to individual enzymes. The carbon compounds became lifeless and lacked useful function without water. Wheh water was added everything worked and life appeared. What is often attributed in life, to statistics, is actually logically explained by the co-partnership with water.

Life, as we know it, evolved in water. Water was/is the micro environment for natural selection at the nanoscale from day one. If we placed life in the Arctic region or the Amazon Jungles, each environment will set parameters that life will need to meet. Life will need to stay warm in the Arctic and say cool in the Amazon; environmental pressures that have a predetermine result. Water had potential needs and life has to conform.

The DNA was selected by the water environment. DNA would not have been selected in any other solvent. If life had evolved in alcohols or any other solvent, which there is no proof it can, other organic or silicon chemicals would need to selected, since the experiments shows that the organic chemicals selected by water, for life, do not work in these solvents.

The experiment did not demonstrate that life cannot appear in solvents other than water. Putting diesel fuel in a gasoline energy will stop it dead. Flushing it out with gasoline brings it back to life. That does not prove that diesel engines cannot exist.

Life on earth arose in a water environment. It is dependent on the specific details of the chemical reactions that take place in water or involving water. The only other polar protic solvents around with non-trivial dielectric constants happen to interfere with the life-sustaining chemical reactions that exist in earthly cells. These solvents include ammonia, propanol, ethanol and methanol.  Injecting any of these into a cell will kill it because it will interfere with the life processes that developed in a water environment.  If the oceans had consisted of methanol and not water, it is impossible for life to have arisen using that solvent and carrier medium instead of water?

BTW was there any attempt to flush out the other solvents with water to see if the cell came back to life? Or is it only the dehydrated and not otherwise contaminated cells that came back to life with water?

Entropy is connected to free energy by the equation G=H-TS, where G is the Gibbs free energy, H is enthalpy, T is temperature and S is entropy.

The second laws says that the S of the universe has to increase. The increase in S lowers the free energy G due to the minus sign in the equation. As universal entropy net increases, to obey the second law, the free energy of the universe gets less and less. There is less net free energy, that is usable to the universe, as time moves forward.

SLOT does not say that S has to increase. It says that S will tend to increase until equilibrium is reached. Hot coffee poured into a hypothetical perfect thermos will reach thermodynamic equilibrium at a certain temperature after it has heated the inner wall of the container. S of the system will remain constant. Notice that there will be local fluctuations. The average kinetic energy of the molecules (temperature) will remain fairly high and they will bounce off each other with random redistributions of that kinetic energy.  But because the kinetic energy has no place to go, S remains constant.

It is the conditions that pertain in the universe that will lead to an overall increase in entropy (S) with as close to statistical certainty as should satisfy any nitpickers and then some.   But notice that local entropy reductions will remain possible as long as there is gravity. Local fluctuations in mass distribution due to random movements of gravitationally bound dust clouds and the like can still lead to star formation/reactivation with large entropy reduction in the neighborhood. SLOT is statistical, not a force in itself.

The universe was originally very hot so the T term or temperature was extreme. The early universe was making free energy unusable at a very high rate. Stars and fusion and extreme heat continue this tradition. There is less universal free energy, in play today, than there was yesterday.

The cooling of the universe was due to its expansion, not SLOT. If the universe did not expand, the high temperature would remain just like in the coffee in the perfect thermos.  But even if the universe did not expand, there would still be local fluctuations and regional gravitational collapses. If conditions were suitable, star formation and resulting fusion reactions or something comparable could still occur. Why? Because all mass in the universe has a positive sign and therefore gravity is always ‘down’. That is the reason that we still notice SLOT after 13+ billion years. There are pockets of low entropy today because of positive mass leading to gravity.

What we call time, moves in the direction of diminishing useable free energy. Entropy and time share the feature of moving in one net direction; forward. Entropy has to increase and time has to move forward. The net loss of useable energy creates a moving target in time.

In the equations of science (except SLOT) time does not move. The time value can be set at some arbitrary point and the system trajectory observed before and after that point. The perceived arrow of time, the fact that we notice certain kinds of differences between past and future, is due to positive mass leading to unidirectional gravity and SLOT.

What has screwed up science, are the clocks that we use to measure time. Clocks cycle which is not how time behaves. This is how energy and waves behave, but not time. Clocks are the wrong analogy for time since they model time as a waves even though time only moves in one direction.

This is like using a thermometer to measure length. It can be done with some ingenuity; expansivity, However, this will perpetuate a practical misconception that time is somehow connected to energy waves.  Free energy is TS and S does not cycle. Clocks do a better measuring TS, since TS is a measure of energy.

Time is not energy waves. It is a dimension along which development occurs. I am not familiar with any model that treats time as waves.

[puppypower]

Time is not energy waves. It is a dimension along which development occurs. I am not familiar with any model that treats time as waves.

There is a difference between the propagation of time, and the clocks we use to measure time. My clock will repeat the same hours each day, even though time moves in one direction to the future and never repeats itself.

Time is 1-D but clock actually model a type of wave phenomena, where the period of the wave is either 24 or 12 hours. Clock time or rather wave time is used throughput physics and science to approximate a 1-D phenomena that is linear and does not repeat.

Time is not like energy, It is not 2-D like a wave, but the clock represents it as such, whether consciously or unconsciously bu long standing traditions. This is why if we are stuck with clocks which time represent time by a wave, the TS term in the free enemy equation i what we are expressing, since that term is a measure of energy. Entropy is 1-D, just like clock time, the TS makes it 2-D like the clock.

Entropy is reversible, but since perpetual motion does not exist, we will need to add more energy, for the local reversal of entropy, than was needed for the forward acton. This is because we need to compensate for the limbo energy that was part of the energy balance for the forward action.. We need to restore the limbo energy to get back to where we began.

I have tried to use the term net energy lost to entropy since some entropy can reverse, but the net affect is ever increasing entropy within the universe, with more and more limbo energy being added. This is how time is related entropy, with both being 1-D.

An example of an entropy clock would be the dead fish clock. We buy a fresh dead fish from the fish market and place it on the kitchen counter in its  time keeper case. The unit of time is when the dead fish  starts to stink. When the clock starts , entropy will taken over and we cannot un-stink the fish due to the second law. Like time it moves only in one direction.

Like in relativity, this clock;s time unit  is dependent on reference. The hotter it is in the kitchen, the faster the unit of time will lapse; spoil faster, and the cooler it is the slower time will lapse relative to a regular wave clock. This is connected to the TS variable, where temperate T will increase the loss of free energy, for any fixed amount of entropy.

Both time and entropy might also be expressed in 3-D, as a spiral moving up a z-axis. From above where the z-axis is not seen, we see a clock on an (x.y) plan. The clock appears to return to 12 noon each day. However, if we also see the z-axis, but it is also moving up the z-axis, so this new 12 noon has more limbo energy.

We as humans perceive time through changes of state, with increasing limbo energy assuring new changes, since what can reverse becomes more and more limited with time.

[puppypower]

Another consideration is there are three states of matter: solid, liquid and gas. A gas can be placed under pressure but not tension. If we try to stretch a gas, all we do is lower the pressure. Solids can be  placed under pressure and tension but not both at the same time and achieve a steady state. If we push and pull a wagon it will move. Frictions adds a third variable.

Liquids are different in that they can be place under tension and pressure and reach steady state. For example, a glass of water open to the atmosphere will have atmospheric pressure. It will also display surface tension at steady state.

Liquid state physics, has different entropy and even time characteristics, than solid and gas states. Gravity is more often about solid and gas state in terms of modeling analogies. Liquid allows for some added things which could help physics models. A glass of water today and 1 billion year ago has not really aged. We will measure the same things the same amount. The rocks of the mountain will weather and sun will grow smaller.

In a liquid, for example, since tension and pressure can both exist at steady state, entropy and entropy reversal can also both exist at the same time at steady state. Entropy benefits by tension; spreading out,  and the reversible of entropy benefits by pressure; compaction. A solid state material, can have a defect locked into place. This added energy pocket assures change. Liquids can adjust for all temporary defects at steady state. This is why entropy is a state variable when it comes to liquids; final equilibrium state that is repeatable. Water is the same now as it was 1 billion year ago.

Water is also a wild card liquid. Water forms hydrogen bonds and hydrogen bonds have both polar and covalent bonding character Each of these two bonding states have different amount of entropy. Water can simply change from one to the other, without breaking the hydrogen bonding and tweak the local entropy in either direction. Water ages slowly.

The added paradox of liquid water is, as we add pressure we push the hydrogen bonds toward the polar side, water defines higher entropy. As we reduce the pressure or add tension. we get the covalent state which, ironically, has lower entropy. This is backwards. The net affect of the paradox of water entropy, is the fine tuning of entropy needed for life. 

This also makes liquid water the most anomalous substance in the known universe, with over 70 known anomalies. Water is the universe's swiss army knife.

Water is not a good time keeper, since its control of entropy makes it timeless. In life, where liquid water meets organic surfaces, timeless and temporal will meet. Water does not change, so the organics have to do it, for the team.

[Kryptid]

Solids can be  placed under pressure and tension but not both at the same time and achieve a steady state.

Yes you can. You can pull a rod from both ends at the same time that you squeeze it in the middle.

[Malamute Lover (OP)]

Time is not energy waves. It is a dimension along which development occurs. I am not familiar with any model that treats time as waves.

There is a difference between the propagation of time, and the clocks we use to measure time. My clock will repeat the same hours each day, even though time moves in one direction to the future and never repeats itself.

Time is 1-D but clock actually model a type of wave phenomena, where the period of the wave is either 24 or 12 hours. Clock time or rather wave time is used throughput physics and science to approximate a 1-D phenomena that is linear and does not repeat.

Time is not like energy, It is not 2-D like a wave, but the clock represents it as such, whether consciously or unconsciously bu long standing traditions. This is why if we are stuck with clocks which time represent time by a wave, the TS term in the free enemy equation i what we are expressing, since that term is a measure of energy. Entropy is 1-D, just like clock time, the TS makes it 2-D like the clock.

Time measurement in scientific experiments is typically by something that works like a stopwatch, from the real thing to an atomic clock. It is the duration of the event that is measured as an absolute value and not related to the day night cycle. In any case, most people do not think of the clock as a smooth wave but more like square waves that segment the day into discrete sections – get ready for work, be at work, be home, sleep. Old retired folk like me do not worry about the clock very much.

Entropy is reversible, but since perpetual motion does not exist, we will need to add more energy, for the local reversal of entropy, than was needed for the forward acton. This is because we need to compensate for the limbo energy that was part of the energy balance for the forward action.. We need to restore the limbo energy to get back to where we began.

I have tried to use the term net energy lost to entropy since some entropy can reverse, but the net affect is ever increasing entropy within the universe, with more and more limbo energy being added. This is how time is related entropy, with both being 1-D.

If the universe were not expanding and if gravity driven energy sources like stars did not exist, maximum entropy would have been achieved long ago. The universe would be very hot. If the universe were expanding (as it is) but the atomic processes that drive stars did not exist, the universe would have achieved a state of very high and very slowly increasing entropy long ago. In either of these cases, there would be some random fluctuations here and there above and below the overall entropy level. To a hypothetical observer in the former case, SLOT would not exist. In the latter case, SLOT would be barely noticeable, overwhelmed by random fluctuations.

If you factor the CMB into your calculations, the overall entropy of the universe is very high already. The reason SLOT is so obvious is that pockets of low entropy continue to be created and sustained by gravity and the existence of the atomic processes that drive stars. SLOT is not an inexorable force in itself. It is a result of circumstances.

An example of an entropy clock would be the dead fish clock. We buy a fresh dead fish from the fish market and place it on the kitchen counter in its  time keeper case. The unit of time is when the dead fish  starts to stink. When the clock starts , entropy will taken over and we cannot un-stink the fish due to the second law. Like time it moves only in one direction.

Like in relativity, this clock;s time unit  is dependent on reference. The hotter it is in the kitchen, the faster the unit of time will lapse; spoil faster, and the cooler it is the slower time will lapse relative to a regular wave clock. This is connected to the TS variable, where temperate T will increase the loss of free energy, for any fixed amount of entropy.

Why should such a low entropy like a fish exist in the first place? It certainly did not come fully formed out of the Big Bang. It came about by a large decrease in local entropy caused by gravity and nuclear processes. Thermodynamics typically does not take gravity into consideration unless one is talking about really large objects.

The fish clock does not work very well. The rate of flow of time is too variable based on external factors. Leave it on the table in the summer and the clock runs fast. Put it in the refrigerator and it runs slower. Even slower in the freezer.  Cook it and can it and later make a tuna sandwich and it can even result in lower entropy in someone’s body. SLOT as a timekeeper does not work because it is statistical and subject to local variations. It is not universal as time is.

Both time and entropy might also be expressed in 3-D, as a spiral moving up a z-axis. From above where the z-axis is not seen, we see a clock on an (x.y) plan. The clock appears to return to 12 noon each day. However, if we also see the z-axis, but it is also moving up the z-axis, so this new 12 noon has more limbo energy.

We as humans perceive time through changes of state, with increasing limbo energy assuring new changes, since what can reverse becomes more and more limited with time.

You are using the image of a cyclical clock to represent actual time when that is just an image you came up with that does not appear to be represented in the real physical world. 

And SLOT is not the cause of time. In a non-expanding universe that had achieved overall thermal equilibrium and there were no stars or other sources of energy, a cesium atom would still go vibrating away at a constant rate regardless of how global or local entropy is changing.

[Bored chemist]

"Why is the Second Law of Thermodynamics (SLOT) time asymmetric? "
Because the Universe is time asymmetric. It had a beginning, and will have some sort of "end".

[Malamute Lover (OP)]

"Why is the Second Law of Thermodynamics (SLOT) time asymmetric? "
Because the Universe is time asymmetric. It had a beginning, and will have some sort of "end".

Distinguishing beginning and end is simply building in an assumption of asymmetry. The laws of physics are time symmetric, If we run 'the movie' backward, there is no violation of those laws. All forces balance properly. SLOT is heuristically derived. We notice it happening. Why should SLOT be different?

I have given my reasoning for why SLOT is asymmetric in time - because of a whopping big asymmetry in the makeup of the universe, that all mass has a positive sign. No negative mass around. This approach also leads to explaining why we see lots of pockets of low entropy after 13+ billion years. of expansion. Positive only mass leads to gravity always being 'down' which allows stars to form and operate, supplying the energy to create other low entropy states.

[hamdani yusuf]

Why is it that the hot coffee gets cooler instead of hotter or just staying the same?

The coffee does get hotter, if it's placed in hotter environment. Or near a strong microwave transmitter.

[Bored chemist]

The laws of physics are time symmetric

Not all of them, for example, there's the 2nd law of thermodynamics