What is time? (Again)

[Edgard Neuman]

Hi, 
Can I give you my point of view ?
The question is in metaphysics, not really physics but not "quackery" philosophy about "inner feelings of time" either (as if humans would be the center of the universe).. I don't wish to discuss it, as metaphysics is by definition out of provability.
I'm placing my thought about the particular laws of physics : I speak only about states of structures in space, laws (how structure's state are related localy) and interactions between structures (without specifying anything more, or any geometry), because I think it's enough to define time. 

My current definition is : 
- time is the accumulation of information in each system. Any structure and history can be "distorted rotated" inverted etc.. But any system is in a state that depends its previous interactions.. most complex system tends to be described as what I call "vortex"  : it's a loop of causality, with some data entering, and some going out, and some of it staying in the loop. Just like what conscience is. Or a rock. Or a molecule (I'm not 100% sure about that : that would need the confirmation of a quantum mechanic expert). And the structure of a system contains partially "memory" that is the component of the state of structure that was added over time.. (but of course, not all data is stored in a system).. (and for us, as systems,  memory is really what we call time)
Somehow, I would suppose that a closed system could only be in one of the three states : not changing, cycling, or chaotic. That's disputable but it seems that reality has laws, and that, in a closed system : each state depends only on the previous one (in a infinitesimal part of space that is).
So for everything, every event that come into it from the outside, perturbate the set of states that were previously reachable.. every data make the system more complex.. 
Consider a book containing a story. If the story obey laws, the story can be deduced from the premises : the start of the book implies the end of the book. The book is just information. Now if somehow, at a point in the book , you "intervene" in the story : the story change into states that depends on what you did. The end of the story can't be explained without mentioning your particular intervention : you added information to the story. 

Another good way of seeing is this : ultimately, each point in the universe because the speed of light is finite, receive some photons from the CMB, photons that were previously out of the visible universe for the point .
Each structure in the universe sees the visible universe constantly growing. So at the very list, at a deeper levels, everything in constantly gaining information. In other words, when a structure interact with an other structure, because of relativity : some part of the past cone of the other structure never were in your past cone : so every interaction you get depends on something new from your history. (You could say that laws are not necessarily bijective, but I think the conservation of information in quantum mechanics exclude that).
It's kind of like in Conway's game of life : each state of a square depends chaotically on its cone of previous squares, and each square depends on at least some squares different from its neighbours.  (I think that "explains" what you measure as time in relativity, but I really fear being banned for this highly speculative idea of mine.. )

At a deeper level, if you consider reality as a mathematical structure, where identity is truly absolute (not depending of where the structure is)  : I think of time as a the creations of new informations (by mixing previous informations) .. and the diffusion of the new information to mix with previous informations.. It's like a big problems that constantly tries to solve itself.

Edited July 30, 2020 by Edgard Neuman

[michel123456]

10 hours ago, Markus Hanke said:

There can be no observer whatsoever in such a universe, neither internal nor external, and I did not postulate one in my original example. This is simply a universe with a single tea cup in it, and otherwise complete empty (vacuum). I also do not require it to be embedded in anything. My point was this:

1. Consider the hypothetical universe as an ordered, uncountably infinite set which consists of all physical locations/points (just like ordinary spacetime manifolds, only in 3D)
2. Each element in the set be of type boolean, i.e. either of value 0 (meaning it is vacuum) or 1 (meaning not vacuum)
3. Not all elements of the set are of value 0, because of the tea cup
4. Because not all elements within the set have identical value, this implies a concept of 'change'

Stop there:

Your point 4 is the nail of the discussion. It clearly shows that we have different definitions of what the word "change" means.

Clearly, to you, "change" equals what I call "different".

To me (and to MigL), "change" equals some process, and thus involves Time.

Which means that we will never agree. We haven't set our definition properly.

1 hour ago, Edgard Neuman said:

Hi, 
Can I give you my point of view ?
The question is in metaphysics, not really physics but not "quackery" philosophy about "inner feelings of time" either (as if humans would be the center of the universe).. I don't wish to discuss it, as metaphysics is by definition out of provability.
I'm placing my thought about the particular laws of physics : I speak only about states of structures in space, laws (how structure's state are related localy) and interactions between structures (without specifying anything more, or any geometry), because I think it's enough to define time. 

My current definition is : 
- time is the accumulation of information in each system. Any structure and history can be "distorted rotated" inverted etc.. But any system is in a state that depends its previous interactions.. most complex system tends to be described as what I call "vortex"  : it's a loop of causality, with some data entering, and some going out, and some of it staying in the loop. Just like what conscience is. Or a rock. Or a molecule (I'm not 100% sure about that : that would need the confirmation of a quantum mechanic expert). And the structure of a system contains partially "memory" that is the component of the state of structure that was added over time.. (but of course, not all data is stored in a system).. (and for us, as systems,  memory is really what we call time)
Somehow, I would suppose that a closed system could only be in one of the three states : not changing, cycling, or chaotic. That's disputable but it seems that reality has laws, and that, in a closed system : each state depends only on the previous one (in a infinitesimal part of space that is).
So for everything, every event that come into it from the outside, perturbate the set of states that were previously reachable.. every data make the system more complex.. 
Consider a book containing a story. If the story obey laws, the story can be deduced from the premises : the start of the book implies the end of the book. The book is just information. Now if somehow, at a point in the book , you "intervene" in the story : the story change into states that depends on what you did. The end of the story can't be explained without mentioning your particular intervention : you added information to the story. 

Another good way of seeing is this : ultimately, each point in the universe because the speed of light is finite, receive some photons from the CMB, photons that were previously out of the visible universe for the point .
Each structure in the universe sees the visible universe constantly growing. So at the very list, at a deeper levels, everything in constantly gaining information. In other words, when a structure interact with an other structure, because of relativity : some part of the past cone of the other structure never were in your past cone : so every interaction you get depends on something new from your history. (You could say that laws are not necessarily bijective, but I think the conservation of information in quantum mechanics exclude that).
It's kind of like in Conway's game of life : each state of a square depends chaotically on its cone of previous squares, and each square depends on at least some squares different from its neighbours.  (I think that "explains" what you measure as time in relativity, but I really fear being banned for this highly speculative idea of mine.. )

At a deeper level, if you consider reality as a mathematical structure, where identity is truly absolute (not depending of where the structure is)  : I think of time as a the creations of new informations (by mixing previous informations) .. and the diffusion of the new information to mix with previous informations.. It's like a big problems that constantly tries to solve itself.

Do not take as granted that your post has been accepted & understood. Personally I had the patience to read it all. Once. I have understood very little of it & I don't see the relevance.

3 hours ago, studiot said:

and the existence of any difference is a change.

See, we are working on the basis of different definitions.

[joigus]

1 hour ago, Edgard Neuman said:

time is the accumulation of information in each system

How do you convert seconds to bits?

2 hours ago, Edgard Neuman said:

Consider a book containing a story. If the story obey laws, the story can be deduced from the premises

That is only too obviously not the case. Fixed set of rules do not in general determine behaviour. Nor true in literature in particular. OTOH, literature obeys patterns rather than strict rules.

41 minutes ago, michel123456 said:

everything in constantly gaining information.

Where does this anti-thermodynamics of yours hold? Not in this universe.

[Markus Hanke]

5 hours ago, Eise said:

As long as you just look at a teacup, or a graph of a function, I fully agree with you.

Ok...and that's all I've been doing, really.

5 hours ago, Eise said:

In my opinion, if somebody says that 'y changes as function of the change of x'

But no one has been saying this...? I don't really understand where this statement is coming from - neither the definition of functions nor of derivatives involves any notion of changing variables. Functions are formally defined as relationships between the elements of domains and codomains (which are sets), and derivatives are functions that involve limits evaluated at a single point, so they are also relationships between elements in sets. This is the textbook definition. So we are talking about relationships here, not processes or actions of any kind. This is what I have been trying to point out all along. 

Edited July 30, 2020 by Markus Hanke

[studiot]

3 hours ago, Eise said:

Can you explain this more. I don't get what you are trying to say.

Of course.

When one charge is positive and and negative the direction will be opposite to the situation when both charges are postive.

We denote this by a plus or minus sign.

2 hours ago, MigL said:

The concept of 'change' only makes sense in a universe with time.
That is why we can observe a universe without time, such as the teacup universe, or the electrostatic universe, and notice change.
we are 'outside' those peculiar universes.

That is because the concept of 'change', ( in effect, for change to be observed ) has to involve the paradigm of time passing.
So we, in this universe notice change even in the teacup/electrostatic universes, but those universes would never have developed the concept of 'change'. How could they ?

( by the way, that's a lot of nos. Was it for emphasis, or three nos for particular points ? )

 

44 minutes ago, michel123456 said:

See, we are working on the basis of different definitions.

 

OK gentlemen, so by you definition I would be incorrect to say that the colour changes from top to bottom on this circular button  ?

[Markus Hanke]

1 hour ago, michel123456 said:

Clearly, to you, "change" equals what I call "different".
To me (and to MigL), "change" equals some process, and thus involves Time.

Yes, the point is precisely to arrive at a suitable definition for the notion of 'change'. 
I for one would say that 'change' is implied by the non-identity of entities, and is thus not a spatiotemporal concept. It is the failure of a set of entities to be homogenous.

3 hours ago, MigL said:

The concept of 'change' only makes sense in a universe with time.

So by this definition, a universe that has no time dimension(s) must be perfectly homogenous in all aspects, purely on account of there being no time?

3 hours ago, MigL said:

That is because the concept of 'change', ( in effect, for change to be observed )

In what way is 'change' ontologically identical to 'observation of change'? That's like saying a tree is the same as the act of observing it - your are postulating the identity between a static entity and a (quite separate) process, which is dubious at best. 

P.S. Very interesting discussion so far, fair play to everyone  But wait...the real fun starts when we raise the stakes a little - what happens when we have a universe that consists of only time dimensions, e.g. a (0+3)-dimensional universe? And would you believe it when I said that such a universe might be entirely indistinguishable from a (3+0)-dimensional one

Edited July 30, 2020 by Markus Hanke

[MigL]

2 hours ago, michel123456 said:

To me (and to MigL), "change" equals some process, and thus involves Time.

No, that is not my viewpoint; change does not need to involve a process.
But we are looking at change, even 2dimensional change such as on a computer screen, from a spatial+temporal perspective.
Such as this ...

1 hour ago, studiot said:

OK gentlemen, so by you definition I would be incorrect to say that the colour changes from top to bottom on this circular button  ?

you only note the change because our universe has a time dimension.
If there was no time, you would not be able to 'see' the change from top to bottom of the circular button.
Our definition of 'change' does not depend on time, but nevertheless, it takes time into consideration.

I'm not saying change needs to have an observer ( or interaction ), but it IS defined by the observer ( who happens to be spatial+temporal ).

1 hour ago, Markus Hanke said:

when we have a universe that consists of only time dimensions, e.g. a (0+3)-dimensional universe? And would you believe it when I said that such a universe might be entirely indistinguishable from a (3+0)-dimensional one

I find that interesting .Could you elaborate ?
But I would have thought three (0+3) time dimensions unworkable.
Three (3+0) spatial dimensions, or a static ( don't want to use unchanging and cause more arguments ) volume, would be different from a singular (0+1) time dimension, or a 'progressing' point ( along a straight line ). So if the three (0+3) time dimension universe obeys the same temporal rules as our time dimension, it would still result in a single point which can progress along any of three time axis ( along a curved line ).
A graph of the system might 'look' the same, but the implications of the motion, or progression, would be entirely different.

Edited July 30, 2020 by MigL

[studiot]

1 hour ago, MigL said:

you only note the change because our universe has a time dimension.
If there was no time, you would not be able to 'see' the change from top to bottom of the circular button.
Our definition of 'change' does not depend on time, but nevertheless, it takes time into consideration.

I'm not saying change needs to have an observer ( or interaction ), but it IS defined by the observer ( who happens to be spatial+temporal )

It is quite unclear from that mixed up paragraph what you mean by change.

You say there is a change and then you imply there is only a change if and only if there is an observer.

Then in the following short paragraph you deny the need for an observer.

 

Personally I do not need time for a spatial only change.

There is no change to the button with time, only with space.
The button was multicoloured when it was formed and will remain so until it is destroyed.

 

Face it.

The property of colour is quite independent of time and may vary with other qualities.

 

[joigus]

3 hours ago, joigus said:

3 hours ago, michel123456 said:

everything in constantly gaining information.

Where does this anti-thermodynamics of yours hold? Not in this universe.

Sorry. It wasn't @michel123456 who said this. It was @Edgard Neuman. The quote function (or my misuse of it) did that.

[MigL]

Your original question was ...

3 hours ago, studiot said:

OK gentlemen, so by you definition I would be incorrect to say that the colour changes from top to bottom on this circular button  ?

I propose that if we didn't inhabit a spatial+temporal universe, neither I, nor you, would be able to say  that it 'changes', so I claim that change is a property applicable to our universe, where we are making the observation from.
Your button may have different top and bottom halves, but it doesn't 'change' in the two dimensional universe of my screen.

Claiming that you can see 'change' in a two dimensional universe from our spatial+temporal vantage point doesn't amount to much.
You cannot claim that 'change' exists in two dimensional space when there is no experiment you can perform, intrinsic to that two dimensional space, that will detect that 'change'.

That is the problem with the definition of change.

[studiot]

26 minutes ago, MigL said:

Your original question was ...

I propose that if we didn't inhabit a spatial+temporal universe, neither I, nor you, would be able to say  that it 'changes', so I claim that change is a property applicable to our universe, where we are making the observation from.
Your button may have different top and bottom halves, but it doesn't 'change' in the two dimensional universe of my screen.

Claiming that you can see 'change' in a two dimensional universe from our spatial+temporal vantage point doesn't amount to much.
You cannot claim that 'change' exists in two dimensional space when there is no experiment you can perform, intrinsic to that two dimensional space, that will detect that 'change'.

That is the problem with the definition of change.

Of course there is a suitable experiment that some 'Flatlander' could perform, without time.

Any Flatlander angel on a pinhead that inhabited the dividing line would be aware of the difference between both sides of the line.

That is fundamental set theory about the difference (that word again) between interior points and boundary points of a set.

But yet again.

The existence of something (including change from one thing/property value to another) depends upon the property or the things.
It is entirely independent of the  presence or absence of an observer or even whther or not an observation is made.

So that button embodies a change that is independent of time.

So let us return to the OP and discuss the OP question

What is time ?

Not what is not time ?

 

When I entered this thread I thought that a good way to explore the Physics of such a difficult question would be to consider properties of time and whether time itself is a property or a 'thing'.

Edited July 30, 2020 by studiot

[Edgard Neuman]

7 hours ago, Edgard Neuman said:

I don't wish to discuss it, as metaphysics is by definition out of provability.

I'm sorry, our way of thinking are too different for me to even have the will to try to understand and describe every difference between us.. 
(OK I can't resist)


If you "understand physics", and you don't see how "information makes time at every level of complexity".. (ok maybe, because you don't see information as the minimum causality possible).. try to understand dominos.. our even how computer works.. or this thread your reading.. or your mind.. or special relativity.. ("information can't go faster than light".. if information can't go faster than light.. try to understand what it implies in terms of flow of information.. picture any system, and how information flows in it..what would happen if it wouldn't).. When you try to define a clock in relativity.. what travels between the parts of your clock ? at least a particle, a signal right ? What is the minimum of a signal ? (information !)

You can't define a "wave" (any wave.. quantum wave. The "idea" of wave) without talking about a field and a perturbation travelling in it, from points to points continuously  (in any type of mathematical structure you can imagine).. what is a wave, if it carry a perturbation across space, but neither matter, nor energy ? (a wave of information..! )

And for the "rules" don't make the system predictable.. so new information pops up everywhere you think (because there's no "between the two"). you can roll the quantum dice, and you get new random numbers on the screen (are numbers not information ? can't I fill my hard drive with random quantum numbers ?).. wouldn't that contradict the conservation of information "https://en.wikipedia.org/wiki/No-hiding_theorem"  
Apparently (according to MIT) a photon carries 10 bits of information.. how many virtual photons are usually in the void ? 

Bye !
 

Edited July 30, 2020 by Edgard Neuman

[joigus]

47 minutes ago, Edgard Neuman said:

try to understand what it implies in terms of flaw of information..

I think you just put your finger on it. It's definitely a flaw of information we're talking about.

[Edgard Neuman]

30 minutes ago, joigus said:

I think you just put your finger on it. It's definitely a flaw of information we're talking about.

sorry (I'm not a native English speaker). 
By the way you seem to love "bits".. here is some facts :
- by definition, probabilities carry "less" than bits. If I tell you "the memory has 60% chance to contain a 1".. how many "bits" did I transfer to you ? 
- any mathematical continuity, implies infinity of "bits".. between to real numbers, you can always find a infinity of new numbers.. and you can have some with a infinity of  uncompressible digits.. so you know you can always find a number, whose writing would need more bits than the first 2

 

Edited July 30, 2020 by Edgard Neuman

[joigus]

Just now, Edgard Neuman said:

sorry (I'm not a native English speaker). 

Neither am I. It's about consistency. I use irony as a tool. Irony is a universal language and helps you make a point. I'm not convinced by your concept of time as information. I don't think you've thought it through.

[Edgard Neuman]

40 minutes ago, joigus said:

Neither am I. It's about consistency. I use irony as a tool. Irony is a universal language and helps you make a point. I'm not convinced by your concept of time as information. I don't think you've thought it through.

how and why ? 
I can believe you're not convince, but I see no hole in my ideas that I would have forgotten to fill. The problem probably comes from what you call "information" that is not what I call "information". You're seeing it as description..
In reality "information" as you see it, doesn't even exist.. the letters on this screen describe poorly reality via a code, and that code exist via physical relationship between sensorial neurons  in our brains (those who see things, and those who read letters).. (we share the code, that is the English language)
But in reality, the matter that carries this "information" doesn't have any relationship to reality itself. If you don't have the code, you have don't have a book, but a inked paper. Some alien reading this text would find regularities, symmetries and even some rules. But without pictures, there's no way they would understand the meaning of the text.
Now if you talk about a series of "bit" as information (as a mathematical property of a set of 0s and 1s).. that's just symmetries.. You can't really compress anything without a code. To zip or unzip a file, you need a specific software. Without knowing the software, you could never read a zip file, because the bits could be anything.. Suppose you code the bits "00000" into somehow 5 x "0" (the bits would be "1010" in some unrealistic software the already know that the first 3 bits are a number)... how do you know that "1010" isn't the bits you coded at first ? or 2 x "10" ?.. 
By "information" I mean the minimum (the Greek "atom") of causality.. (that's the meaning used in relativity.. "no information can't travel faster than life" really speaks about causality)

 

Edited July 30, 2020 by Edgard Neuman

[joigus]

5 minutes ago, Edgard Neuman said:

The problem probably comes from what you call "information" that is not what I call "information". You're seeing it as description..

My concept of information comes from Shannon, which fits the definition of entropy given by Boltzmann (information deficit). There are other definitions of entropy that are more useful in different contexts and are qualitatively equivalent. None of those do I recognize in what you say.

For example, you've got Rényi entropy: https://arxiv.org/pdf/1102.2098.pdf

In some respects it's a more solid definition, meaning that in some systems for which Boltzmann entropy is not well defined, Rényi entropy is.

And you still haven't answered: What's the connection between time and entropy? Information defines a thermodynamic arrow of time, but not its units.

Another thing you haven't answered: Nature goes from more information to less information. It's the opposite of what you suggested.

[studiot]

25 minutes ago, Edgard Neuman said:

But in reality, the matter that carries this "information" doesn't have any relationship to reality itself.

This is a Physics forum.

What 'matter' are you referring to that has no relationship to reality ?

[Edgard Neuman]

17 minutes ago, joigus said:

My concept of information comes from Shannon, which fits the definition of entropy given by Boltzmann (information deficit). There are other definitions of entropy that are more useful in different contexts and are qualitatively equivalent. None of those do I recognize in what you say.

For example, you've got Rényi entropy: https://arxiv.org/pdf/1102.2098.pdf

In some respects it's a more solid definition, meaning that in some systems for which Boltzmann entropy is not well defined, Rényi entropy is.

And you still haven't answered: What's the connection between time and entropy? Information defines a thermodynamic arrow of time, but not its units.

Another thing you haven't answered: Nature goes from more information to less information. It's the opposite of what you suggested.

You try to make me understand your ideas (I don't need to, because I already have a answer to the question  ).. first : entropy is not "irreversible".. you should know that all law of physics ARE time reversible. when people say "entropy" can't be reversed, it's not entirely true. In theory, if you reverse the speed "every molecules" of a gas, the gas go back to the corner.. If you want to unbreak a glass, you just have to put it back and restore the molecular liasons that were broken.. and you can "unmix" liquids (it's just complicated and require skilled chemists)
so already, there's a "flaw"
Entropy just talk about probabilities for system to be in specific stats. In reality, a set of card, when it's ordered, is not different to when it's not ordered (except in your mind, where "some cards go after some others cards). You choose to believe specific states are "special" because they exhibits symmetries.. but even that's a subjective idea. Symmetries you observe in nature, (like Chrystal) are just minimum states.. minimum states often have symmetries (because they obey local constraints) but not always (like quasi-christals)
It's all about probabilities : systems flows from states to states, and when the flow of states (in the space of states) converges to some more probable states, matter often ends up in those states. But that's not "time". because... conservation of quantum information precisely and explicitly contradict this "convergence of states".. 🤷‍♂️.. A perfect oscillator (like a isolated atom), or even a chaotic oscillator doesn't gain or lose entropy, while it still "evolves" in time.. 
I think what you see as entropy is just a redistribution of randomness.

Edited July 30, 2020 by Edgard Neuman

[joigus]

2 minutes ago, Edgard Neuman said:

when people say "entropy" can't be reversed

Nobody says that. That's not how you formulate irreversibility.

3 minutes ago, Edgard Neuman said:

I think what you see as entropy is just a redistribution of randomness.

No. It's a measure of ignorance or "randomness" if you will. And yours is going through the roof.

[Edgard Neuman]

3 minutes ago, joigus said:

Nobody says that. That's not how you formulate irreversibility.

No. It's a measure of ignorance or "randomness" if you will. And yours is going through the roof.

So if entropy can be reversed, how could it define time..? Can time be reversed now ? What about the grandfather paradox ? 
You can't explain time with something that can be reversed. And does the entropy of a single atom change ? So how could we built atomic clocks ? 

Edited July 30, 2020 by Edgard Neuman

[joigus]

1 minute ago, Edgard Neuman said:

So if entropy can be reversed, how could it define time..?

That's not what I said. "Reverse entropy" doesn't make any sense. You must mean "reverse entropy change". How could it define time? Entropy doesn't define time.

[Edgard Neuman]

22 minutes ago, joigus said:

That's not what I said. "Reverse entropy" doesn't make any sense. You must mean "reverse entropy change". How could it define time? Entropy doesn't define time.

I understand that entropy speaks about "closed system".. can't diminish (the laws of thermodynamics)..but when entropy stay the same (because the system is stable) does time stops.. ? and if it stops, what does make it start again ? (information !)
Suppose you take a empty box . You carefully compute the trajectory of every molecule you throw in the box, in a specific way, that is the exact opposite of where the molecule would have pop up if the box first contained ice. You throw the molecule, close the box. The molecules bounce, and according to your calculation, ends up in the corner of the box.. 


The subject of the thread is "what is time". I gave you my answer. You talk about the classic theory that the arrow of time is somehow explained by the laws of thermodynamics (the entropy thing). So what are you trying to say if you're not talking about that ?? 

45 minutes ago, studiot said:

This is a Physics forum.

What 'matter' are you referring to that has no relationship to reality ?

Ok that sentence wasn't very clear. 
I mean that the matter that carries the information (like the screen, a computer, a brain, a book.. information doesn't exist without matter to carry it) does not have a relationship with the reality described by the information (the meaning). A book, without a dictionary, is not enough to recreate the story. Therefor this "information" does not "exist" (something that exists, by definition, is something that can be lost and found..).. the meaning is only in the brains of people.

Edited July 30, 2020 by Edgard Neuman

[joigus]

2 minutes ago, Edgard Neuman said:

I understand that entropy speaks about "closed system".. can't diminish (the laws of thermodynamics).. but when entropy stay the same (because the system is stable) does time stops.. ? and if it stops, what does make it start again ? 

Fine-grained, or microscopic entropy, never changes. It's a constant. It's the volume of phase space; a measure of how much information is in the system. That's called Liouville's theorem. Dynamical systems conserve the distinctions, the amount of information. It's just that evolution always de-correlates most of your system's dynamical variables with the "macroscopic handles" you may establish to study it (volume, pressure, fields). So most of this dynamical information is lost for your macroscopic "description handles", in my figure of speech.

Coarse-grained, or macroscopic entropy, always increases for closed systems.

Time? You're trying to take too big a leap here. Time has to do with entropy growth (its direction), but it's not defined by it.

Time doesn't stop. What makes you think it does?

The grandfather paradox has to do with geometry of space-time, not with entropy.

1 hour ago, Edgard Neuman said:

no information can't travel faster than life

What's that about???

[Edgard Neuman]

15 minutes ago, joigus said:

Fine-grained, or microscopic entropy, never changes. It's a constant. It's the volume of phase space; a measure of how much information is in the system. That's called Liouville's theorem. Dynamical systems conserve the distinctions, the amount of information.

Dynamic "closed" system.. Or has I said from the beginning.. The universe IS EXPANDING. You get "new photons" at any point of the universe (directly or indirectly).. (and I suppose "photons" are not the only carrier of information, gravitational waves, any particle.. any event.. any "information".. that's just to explain that because of relativity : any point of space time get to interact with new points of space time as time go one)..
 No system is really closed.. that's why I say information is time. 

Quote

 

It's just that evolution always de-correlates most of your system's dynamical variables with the "macroscopic handles" you may establish to study it (volume, pressure, fields). So most of this dynamical information is lost for your macroscopic "description handles", in my figure of speech.

I don't disagree with that.. I almost wrote a text that said that "measurements" are just summaries of reality (classification into sets)

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Coarse-grained, or macroscopic entropy, always increases for closed systems.

I was explaining that if entropy  (a property of a system can go backward) can go backward. As I said entropy is a statistical property, in reality, law of physics are time reversible.. So the real reason why entropy "always increase" is because of initial conditions. And reversed system, that goes back into a ordered stable state, is perfectly possible in respect to the laws of physics. 

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Time? You're trying to take too big a leap here. Time has to do with entropy growth (its direction), but it's not defined by it.

Time doesn't stop. What makes you think it does?

Entropy can stop changing. I mean therefor it can't define time. But I don't think "time can't stop". You talking about your idea of time, as something that occur spontaneously in matter (like the spining of electrons in atoms, or the "oscillations of wave"). But for a true objective idea of time, independent of scale, can stop. You know, when nothing happen.  The "quantum" time, is just a level of time..

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The grandfather paradox has to do with geometry of space-time, not with entropy.

Therefor it can't be time. That's it. You talked about entropy, you know why you do. I don't ! 

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What's that about???

sorry : *Light*

Edited July 30, 2020 by Edgard Neuman