Time yet to reconsider "the arrow of time"?

Grumblenuts

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The arrow of time is the "one-way direction" or "asymmetry" of time. The thermodynamic arrow of time is provided by the second law of thermodynamics, which says that in an isolated system, entropy tends to increase with time. Entropy can be thought of as a measure of microscopic disorder; thus the second law implies that time is asymmetrical with respect to the amount of order in an isolated system: as a system advances through time, it becomes more statistically disordered. This asymmetry can be used empirically to distinguish between future and past, though measuring entropy does not accurately measure time. Also, in an open system, entropy can decrease with time.
With that in mind, let's presume here that the "Universe is Not Expanding After All" (or may not be) and that no practical system can be truly "isolated" or "closed" in reality. Does entropy really force time to go one-way? What if the Universe began shrinking?
 

gipper

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What is time?
 
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Grumblenuts

Grumblenuts

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What is time?
I see "Today at 12:57 PM." A moment ago it said "59 minutes ago." I gather that's involved. You can actually click the link underneath and time travel back to your post if you want.
 
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Grumblenuts

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Phones ruin everything.
 

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The arrow of time is the "one-way direction" or "asymmetry" of time. The thermodynamic arrow of time is provided by the second law of thermodynamics, which says that in an isolated system, entropy tends to increase with time. Entropy can be thought of as a measure of microscopic disorder; thus the second law implies that time is asymmetrical with respect to the amount of order in an isolated system: as a system advances through time, it becomes more statistically disordered. This asymmetry can be used empirically to distinguish between future and past, though measuring entropy does
not accurately measure time. Also, in an open system, entropy can decrease with time.
With that in mind, let's presume here that the "Universe is Not Expanding After All" (or may not be) and that no practical system can be truly "isolated" or "closed" in reality. Does entropy really force time to go one-way? What if the Universe began shrinking?
Entropy is not related to universe expansion !!
2 different things .
Entropy is about thermodynamics
Take an egg ???
There are billions of ways to break it but only a few ways to take a splattered egg and make it whole .
It’s possible in a parallel universe that the river of entropy runs reverse ??
So you’re born a very old man and die as a infant
 

james bond

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The arrow of time is the "one-way direction" or "asymmetry" of time. The thermodynamic arrow of time is provided by the second law of thermodynamics, which says that in an isolated system, entropy tends to increase with time. Entropy can be thought of as a measure of microscopic disorder; thus the second law implies that time is asymmetrical with respect to the amount of order in an isolated system: as a system advances through time, it becomes more statistically disordered. This asymmetry can be used empirically to distinguish between future and past, though measuring entropy does not accurately measure time. Also, in an open system, entropy can decrease with time.
With that in mind, let's presume here that the "Universe is Not Expanding After All" (or may not be) and that no practical system can be truly "isolated" or "closed" in reality. Does entropy really force time to go one-way? What if the Universe began shrinking?
What happened to your Bernie avatar? It was perfect for 2016 and you. I can see why you want to go backward in time.

Entropy and thermodynamics have to do with heat flow causing energy transfer. This is due to temperature differences in parts of the universe. As you know, entropy increases when temperature differences cause heat to flow from a hot place to a cold place. They have nothing to do with time direction. At least, you're not practicing science is atheism.
 
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Grumblenuts

Grumblenuts

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The arrow of time is the "one-way direction" or "asymmetry" of time. The thermodynamic arrow of time is provided by the second law of thermodynamics, which says that in an isolated system, entropy tends to increase with time. Entropy can be thought of as a measure of microscopic disorder; thus the second law implies that time is asymmetrical with respect to the amount of order in an isolated system: as a system advances through time, it becomes more statistically disordered. This asymmetry can be used empirically to distinguish between future and past, though measuring entropy does
not accurately measure time. Also, in an open system, entropy can decrease with time.
With that in mind, let's presume here that the "Universe is Not Expanding After All" (or may not be) and that no practical system can be truly "isolated" or "closed" in reality. Does entropy really force time to go one-way? What if the Universe began shrinking?
Entropy is not related to universe expansion !!
2 different things .
Entropy is about thermodynamics
Take an egg ???
There are billions of ways to break it but only a few ways to take a splattered egg and make it whole .
It’s possible in a parallel universe that the river of entropy runs reverse ??
So you’re born a very old man and die as a infant
Interesting response. I don't know. That's why I'm asking. I've long had issues with the so-called "Laws" of thermodynamics as I've discussed elsewhere. My impression has been that we really don't understand entropy very well at all yet..

"Entropy is not related to universe expansion !!" - why not?
"Entropy is about thermodynamics" - universe expansion is not related to thermodynamics?
 

miketx

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Time flies like an arrow, fruit flies like a banana - karl marx
 
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Grumblenuts

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^Groucho.
Time/Space is the 4th Dimension that is created by gravity
Again, I dunno, but seems to me "Space" is logically one dimension, "Time" another (perhaps). Cartesian or polar coordinate systems being only arbitrary point location schemes. "Space" always strikes me as a nothing begging for further definition.
 

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The arrow of time is the "one-way direction" or "asymmetry" of time. The thermodynamic arrow of time is provided by the second law of thermodynamics, which says that in an isolated system, entropy tends to increase with time. Entropy can be thought of as a measure of microscopic disorder; thus the second law implies that time is asymmetrical with respect to the amount of order in an isolated system: as a system advances through time, it becomes more statistically disordered. This asymmetry can be used empirically to distinguish between future and past, though measuring entropy does not accurately measure time. Also, in an open system, entropy can decrease with time.
With that in mind, let's presume here that the "Universe is Not Expanding After All" (or may not be) and that no practical system can be truly "isolated" or "closed" in reality. Does entropy really force time to go one-way? What if the Universe began shrinking?
Open and closed systems are a human construct to help us put things in tidy boxes. Time is not an arrow, has no symmetry or asymmetry.
 

miketx

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The arrow of time is the "one-way direction" or "asymmetry" of time. The thermodynamic arrow of time is provided by the second law of thermodynamics, which says that in an isolated system, entropy tends to increase with time. Entropy can be thought of as a measure of microscopic disorder; thus the second law implies that time is asymmetrical with respect to the amount of order in an isolated system: as a system advances through time, it becomes more statistically disordered. This asymmetry can be used empirically to distinguish between future and past, though measuring entropy does not accurately measure time. Also, in an open system, entropy can decrease with time.
With that in mind, let's presume here that the "Universe is Not Expanding After All" (or may not be) and that no practical system can be truly "isolated" or "closed" in reality. Does entropy really force time to go one-way? What if the Universe began shrinking?
Open and closed systems are a human construct to help us put things in tidy boxes. Time is not an arrow, has no symmetry or asymmetry.
You're correct, because arrows always hit the ground and stop. Even if you use a whisker biscuit.

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Grumblenuts

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The arrow of time is the "one-way direction" or "asymmetry" of time. The thermodynamic arrow of time is provided by the second law of thermodynamics, which says that in an isolated system, entropy tends to increase with time. Entropy can be thought of as a measure of microscopic disorder; thus the second law implies that time is asymmetrical with respect to the amount of order in an isolated system: as a system advances through time, it becomes more statistically disordered. This asymmetry can be used empirically to distinguish between future and past, though measuring entropy does not accurately measure time. Also, in an open system, entropy can decrease with time.
With that in mind, let's presume here that the "Universe is Not Expanding After All" (or may not be) and that no practical system can be truly "isolated" or "closed" in reality. Does entropy really force time to go one-way? What if the Universe began shrinking?
Open and closed systems are a human construct to help us put things in tidy boxes. Time is not an arrow, has no symmetry or asymmetry.
Well that's the presumption I'm asking people to consider.. still, I ain't getting any younger.. You?
 

Erinwltr

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The arrow of time is the "one-way direction" or "asymmetry" of time. The thermodynamic arrow of time is provided by the second law of thermodynamics, which says that in an isolated system, entropy tends to increase with time. Entropy can be thought of as a measure of microscopic disorder; thus the second law implies that time is asymmetrical with respect to the amount of order in an isolated system: as a system advances through time, it becomes more statistically disordered. This asymmetry can be used empirically to distinguish between future and past, though measuring entropy does not accurately measure time. Also, in an open system, entropy can decrease with time.
With that in mind, let's presume here that the "Universe is Not Expanding After All" (or may not be) and that no practical system can be truly "isolated" or "closed" in reality. Does entropy really force time to go one-way? What if the Universe began shrinking?
Open and closed systems are a human construct to help us put things in tidy boxes. Time is not an arrow, has no symmetry or asymmetry.
Well that's the presumption I'm asking people to consider.. still, I ain't getting any younger.. You?
Of course I am. Aging isn't time.
 

toobfreak

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The arrow of time is the "one-way direction" or "asymmetry" of time. The thermodynamic arrow of time is provided by the second law of thermodynamics, which says that in an isolated system, entropy tends to increase with time. Entropy can be thought of as a measure of microscopic disorder; thus the second law implies that time is asymmetrical with respect to the amount of order in an isolated system: as a system advances through time, it becomes more statistically disordered. This asymmetry can be used empirically to distinguish between future and past, though measuring entropy does not accurately measure time. Also, in an open system, entropy can decrease with time.
With that in mind, let's presume here that the "Universe is Not Expanding After All" (or may not be) and that no practical system can be truly "isolated" or "closed" in reality. Does entropy really force time to go one-way? What if the Universe began shrinking?
But it is without any doubt.

But is has to be.

Yes.

Then time would still be going forward.

Since things happen, and that is necessary for the structure of matter (the spinning of the electron and the vibration of quanta), then time can only go forward otherwise events would be undone making the fabric of space impossible.

You cannot violate the space time matrix yet still expect it to stand while events unravel. It doesn't work that way. Instead, the only option is to travel back along the timeline by skips and hops (a warp) with your own timeline and the places you skip to still moving forward as well while the actual net universal timeline itself never stops moving forward.
 

ding

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Does entropy really force time to go one-way?
No. It's the other way around. Except it's not because of time that entropy increased. It is because there are no 100% efficient thermodynamic processes.

...in an open system, entropy can decrease with time.
Only because energy can be added to the system.

A better way of looking at entropy is that there are no 100% efficient transactions between matter and energy. That for every transaction there will be usable energy lost to the system. That does not mean that energy or matter were destroyed though. It means the usable energy of the system has decreased.

So an open system that has energy added to it can have it's usable energy increased by the addition of energy from outside the system.
 

ding

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The arrow of time is the "one-way direction" or "asymmetry" of time. The thermodynamic arrow of time is provided by the second law of thermodynamics, which says that in an isolated system, entropy tends to increase with time. Entropy can be thought of as a measure of microscopic disorder; thus the second law implies that time is asymmetrical with respect to the amount of order in an isolated system: as a system advances through time, it becomes more statistically disordered. This asymmetry can be used empirically to distinguish between future and past, though measuring entropy does not accurately measure time. Also, in an open system, entropy can decrease with time.
With that in mind, let's presume here that the "Universe is Not Expanding After All" (or may not be) and that no practical system can be truly "isolated" or "closed" in reality. Does entropy really force time to go one-way? What if the Universe began shrinking?
Open and closed systems are a human construct to help us put things in tidy boxes. Time is not an arrow, has no symmetry or asymmetry.
Technically everything we know are human constructs. That doesn't mean they don't exist in and of themselves though. They do. It's only that their existence is manifested in our minds.

George Wald explains...

"...It is primarily physicists who in recent times have expressed most clearly and forthrightly this pervasive relationship between mind and matter, and indeed at times the primacy of mind. Arthur Eddington in 1928 wrote, “the stuff of the world is mind‑stuff ... The mind‑stuff is not spread in space and time.... Recognizing that the physical world is entirely abstract and without ‘actuality’ apart from its linkage to consciousness, we restore consciousness to the fundamental position . . .”

Von Weizsacker in 1971 states as “a new and, I feel, intelligible interpretation of quantum theory” what he calls his “Identity Hypothesis: Consciousness and matter are different aspects of the same reality.”

I like most of all Wolfgang Pauli’s formulation, from 1952: “To us . . . the only acceptable point of view appears to be the one that recognizes both sides of reality -- the quantitative and the qualitative, the physical and the psychical -- as compatible with each other, and can embrace them simultaneously . . . It would be most satisfactory of all if physis and psyche (i.e., matter and mind) could be seen as complementary aspects of the same reality.”

What this kind of thought means essentially is that one has no more basis for considering the existence of matter without its complementary aspect of mind, than for asking that elementary particles not also be waves.


As for this seeming a strange viewpoint for a scientist -- at least until one gets used to it -- as in so many other instances, what is wanted is not so much an acceptable concept as an acceptable rhetoric. If I say, with Eddington, “the stuff of the world is mind‑stuff,” that has a metaphysical ring. But if I say that ultimate reality is expressed in the solutions of the equations of quantum mechanics, quantum electrodynamics, and quantum field theory -- that sounds like good, modern physics. Yet what are those equations, indeed what is mathematics, but mind‑stuff? -- virtually the ultimate in mind‑stuff and for that reason deeply mysterious..."

 

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