APOD: Split the Universe (2017 Apr 01)

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Re: APOD: Split the Universe (2017 Apr 01)

Postby rstevenson » Sat Apr 08, 2017 5:29 pm

Chris Peterson wrote:
rstevenson wrote:
Chris Peterson wrote:... Regarding the Go playing computer, I imagine the program must observe some kind of probabilistic rules. But Go is too complex to really have any such rules that you can write down. If that's what the computer is using, it figured them out for itself.

But surely the computer could now be instructed to print out its rules.

It has no obvious rules. Could you write out the rules you use to play chess (let alone Go)? At best you might be able to express a broad strategy based on the board position and the next few moves, or your reasoning behind one specific move. No Grand Master can deliver a set of rules to a newbie chess player and have him become a Grand Master immediately himself.

This Go system, like your own mind, is well beyond our ability to fully analyze. Whether it's impossible or just very difficult may be uncertain, but from a practical standpoint, neither can be seen as deterministic. If the same board pattern came around again at some time in the future, neither of you would necessarily choose the same move.

I think you missed my point, probably because I didn't fully state it.

The Go-playing computer has a finite digital memory, which is in a particular state at a particular time. (We know next to nothing about our own memories, but there's good reason to think they're not digital, and certainly they're not accessible the way a computer's memory is.) The Go-playing computer can be told, via programming, to print out whatever is in its memory regarding its strategy for working through its decision tree at that particular time. That would be the strategy it is using at that time.

I agree this would not be a complete set of instructions if it is changing its strategy as time goes on, which I suppose it is doing. But it is already able to beat world-class human players, so this print out would be a world-class strategy. (It will need to be translated from, I guess, machine code to a more easily readable form.) The printout, and even more so the translation, would be very large, of course, but not infinite.

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Re: APOD: Split the Universe (2017 Apr 01)

Postby Chris Peterson » Sat Apr 08, 2017 6:10 pm

rstevenson wrote:
Chris Peterson wrote:It has no obvious rules. Could you write out the rules you use to play chess (let alone Go)? At best you might be able to express a broad strategy based on the board position and the next few moves, or your reasoning behind one specific move. No Grand Master can deliver a set of rules to a newbie chess player and have him become a Grand Master immediately himself.

This Go system, like your own mind, is well beyond our ability to fully analyze. Whether it's impossible or just very difficult may be uncertain, but from a practical standpoint, neither can be seen as deterministic. If the same board pattern came around again at some time in the future, neither of you would necessarily choose the same move.

I think you missed my point, probably because I didn't fully state it.

The Go-playing computer has a finite digital memory, which is in a particular state at a particular time. (We know next to nothing about our own memories, but there's good reason to think they're not digital, and certainly they're not accessible the way a computer's memory is.) The Go-playing computer can be told, via programming, to print out whatever is in its memory regarding its strategy for working through its decision tree at that particular time. That would be the strategy it is using at that time.

No, I didn't miss your point. Sure, you could look at the state the machine was in just before it made its move, and "predict" what it was going to do. But that wouldn't tell you anything about its strategy, nor would you be able to determine how it chose that move (except in the most mechanistic sense... like the way you can predict that a person will move their finger by looking at their brain activity... it doesn't tell you why they moved their finger).

I agree this would not be a complete set of instructions if it is changing its strategy as time goes on, which I suppose it is doing. But it is already able to beat world-class human players, so this print out would be a world-class strategy.

No, it would only reflect a world-class move. The strategy behind it is hopelessly lost in millions of iterations of self-modifying parameters as well as stochastic elements.
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Re: APOD: Split the Universe (2017 Apr 01)

Postby rstevenson » Sun Apr 09, 2017 1:20 am

Chris Peterson wrote:... Sure, you could look at the state the machine was in just before it made its move, and "predict" what it was going to do. But that wouldn't tell you anything about its strategy, nor would you be able to determine how it chose that move (except in the most mechanistic sense... like the way you can predict that a person will move their finger by looking at their brain activity... it doesn't tell you why they moved their finger).

I was about to answer that humans can have a why but a computer can't, when I realized that's exactly what you're suggesting, that this particular computer has a reason for making it's choice over and above the programming it contains (including its self-modified programming.) So it's sentient, by however limited a definition of sentience we might need to use. Now that's interesting!

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Re: APOD: Split the Universe (2017 Apr 01)

Postby Chris Peterson » Sun Apr 09, 2017 1:30 am

rstevenson wrote:
Chris Peterson wrote:... Sure, you could look at the state the machine was in just before it made its move, and "predict" what it was going to do. But that wouldn't tell you anything about its strategy, nor would you be able to determine how it chose that move (except in the most mechanistic sense... like the way you can predict that a person will move their finger by looking at their brain activity... it doesn't tell you why they moved their finger).

I was about to answer that humans can have a why but a computer can't, when I realized that's exactly what you're suggesting, that this particular computer has a reason for making it's choice over and above the programming it contains (including its self-modified programming.) So it's sentient, by however limited a definition of sentience we might need to use. Now that's interesting!

I don't know if we can say it has a reason "over and above the programming it contains"... but then I don't know if I can say that for humans, either.
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Re: APOD: Split the Universe (2017 Apr 01)

Postby neufer » Mon Apr 10, 2017 10:38 pm

Click to play embedded YouTube video.
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Re: APOD: Split the Universe (2017 Apr 01)

Postby BDanielMayfield » Tue Apr 11, 2017 4:25 pm

Having just watched the above video my thinking bifurcates. Much of it went over my head of course, but it otoh it kinda spoke to my heartfelt love of math and science. The other side of my thoughts go like, "you stepped in whaaaat?"

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Re: APOD: Split the Universe (2017 Apr 01)

Postby Fred the Cat » Fri Apr 14, 2017 3:10 pm

This is food for thought. I wasn’t aware of the research already underway by Penrose and others showing my knowledge is still in non-equilibrium.

At least the food has an interesting taste. :wink:
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Re: APOD: Split the Universe (2017 Apr 01)

Postby neufer » Fri Apr 14, 2017 3:46 pm

BDanielMayfield wrote:
Having just watched the above video my thinking bifurcates. Much of it went over my head of course, but it otoh it kinda spoke to my heartfelt love of math and science. The other side of my thoughts go like, "you stepped in whaaaat?"

My take on what Antony Valentini is saying about wave particle duality
(and the whole existential problem involving the instantaneous collapse of a wave function)
is basically this:

    At times an electron can be both a particle and a wave, carry on conversations.
    At other times, the particle half took over completely.
    The electron was NEVER all wave, but it was often only particle.
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Click to play embedded YouTube video.

Dr. Fred Richmond: Now to understand it the way I understood it, hearing it from the mother... that is, from the mother half of Norman's mind... you have to go back ten years, to the time when Norman murdered his mother and her lover. Now he was already dangerously disturbed, had been ever since his father died. His mother was a clinging, demanding woman, and for years the two of them lived as if there was no one else in the world. Then she met a man... and it seemed to Norman that she 'threw him over' for this man. Now that pushed him over the line and he killed 'em both. Matricide is probably the most unbearable crime of all... most unbearable to the son who commits it. So he had to erase the crime, at least in his own mind. He stole her corpse. A weighted coffin was buried. He hid the body in the fruit cellar. Even treated it to keep it as well as it would keep. And that still wasn't enough. She was there! But she was a corpse. So he began to think and speak for her, give her half his life, so to speak. At times he could be both personalities, carry on conversations. At other times, the mother half took over completely. Now he was never all Norman, but he was often only mother.
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Re: APOD: Split the Universe (2017 Apr 01)

Postby BDanielMayfield » Sat Apr 15, 2017 10:37 am

I don't know why this didn't occur to me sooner, but the notion that the choices we make can actually "split the universe" into multiple copies can not be true because it violates conservation of energy.

Both of my personalities agree on this. :lol2:

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Re: APOD: Split the Universe (2017 Apr 01)

Postby Chris Peterson » Sat Apr 15, 2017 1:49 pm

BDanielMayfield wrote:I don't know why this didn't occur to me sooner, but the notion that the choices we make can actually "split the universe" into multiple copies can not be true because it violates conservation of energy.

Conservation of energy is an empirical principle, not a well defined law of nature. It is probably violated in a number of general relativity cases, and possibly some quantum mechanical cases, as well. Violating conservation of energy is not necessarily a good argument against something. The situation is further complicated by the fact that it applies to closed systems, and when we're talking about the Universe, we do not know if or how it is closed. Alternatively, the condition may be satisfied so long as each individual universe which exists after a decision has itself conserved energy. After all, the law may only apply within any given universe; creating a new one is a different situation.
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Re: APOD: Split the Universe (2017 Apr 01)

Postby BDanielMayfield » Sat Apr 15, 2017 2:09 pm

Chris Peterson wrote:
BDanielMayfield wrote:I don't know why this didn't occur to me sooner, but the notion that the choices we make can actually "split the universe" into multiple copies can not be true because it violates conservation of energy.

Conservation of energy is an empirical principle, not a well defined law of nature. It is probably violated in a number of general relativity cases, and possibly some quantum mechanical cases, as well. Violating conservation of energy is not necessarily a good argument against something. The situation is further complicated by the fact that it applies to closed systems, and when we're talking about the Universe, we do not know if or how it is closed. Alternatively, the condition may be satisfied so long as each individual universe which exists after a decision has itself conserved energy. After all, the law may only apply within any given universe; creating a new one is a different situation.

Wow. I've always heard the declaration, (like it was carved in stone or something), that Energy can neither be created or destroyed. Thus I've always thought that it is a fundamental truth of physics. Where in GR, in the macro world, is energy conservation violated?

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Re: APOD: Split the Universe (2017 Apr 01)

Postby neufer » Sat Apr 15, 2017 2:11 pm

Chris Peterson wrote:
BDanielMayfield wrote:
I don't know why this didn't occur to me sooner, but the notion that the choices we make can actually "split the universe" into multiple copies can not be true because it violates conservation of energy.

Conservation of energy is an empirical principle, not a well defined law of nature. It is probably violated in a number of general relativity cases, and possibly some quantum mechanical cases, as well. Violating conservation of energy is not necessarily a good argument against something. The situation is further complicated by the fact that it applies to closed systems, and when we're talking about the Universe, we do not know if or how it is closed. Alternatively, the condition may be satisfied so long as each individual universe which exists after a decision has itself conserved energy. After all, the law may only apply within any given universe; creating a new one is a different situation.

A good discussion for A. Noether time, perhaps.
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Re: APOD: Split the Universe (2017 Apr 01)

Postby neufer » Sat Apr 15, 2017 2:26 pm

BDanielMayfield wrote:
Where in GR, in the macro world, is energy conservation violated?

Where in GR, in the macro world, are those multiple copies?
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Re: APOD: Split the Universe (2017 Apr 01)

Postby Chris Peterson » Sat Apr 15, 2017 2:29 pm

BDanielMayfield wrote:
Chris Peterson wrote:
BDanielMayfield wrote:I don't know why this didn't occur to me sooner, but the notion that the choices we make can actually "split the universe" into multiple copies can not be true because it violates conservation of energy.

Conservation of energy is an empirical principle, not a well defined law of nature. It is probably violated in a number of general relativity cases, and possibly some quantum mechanical cases, as well. Violating conservation of energy is not necessarily a good argument against something. The situation is further complicated by the fact that it applies to closed systems, and when we're talking about the Universe, we do not know if or how it is closed. Alternatively, the condition may be satisfied so long as each individual universe which exists after a decision has itself conserved energy. After all, the law may only apply within any given universe; creating a new one is a different situation.

Wow. I've always heard the declaration, (like it was carved in stone or something), that Energy can neither be created or destroyed. Thus I've always thought that it is a fundamental truth of physics. Where in GR, in the macro world, is energy conservation violated?

Follow up on Art's reference to Noether's theorem. In the QM world, interesting issues arise in considering vacuums and virtual particles. In GR, interesting issues arise when considering different frames of reference.

In any case, however, conservation of energy is more of an observed principle than it is something with strong theoretical underpinnings. And it's all moot when we consider multiple universes (which is essentially what a split-at-every-decision model is), since there's absolutely no basis for assuming it would apply across those.
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Re: APOD: Split the Universe (2017 Apr 01)

Postby BDanielMayfield » Sat Apr 15, 2017 3:31 pm

neufer wrote:
BDanielMayfield wrote:
Where in GR, in the macro world, is energy conservation violated?

Where in GR, in the macro world, are those multiple copies?


Nowhere. They don't exist in real spacetime. The supposed other universes are purely imaginary. We all live in the one real universe which we all effect by our actions as far as our individual spheres of influence extend.

We live in the real U, which is the sum of all paths actually taken by all mater and energy inside it, both animate and inanimate. The paths not taken are iUx, which are infinite but not real.

(To the non math heads out there i is the imaginary number, the square root of negative one. As you cannot take the square root of a negative number the result isn't real, it's imaginary. Imagine that.)

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Re: APOD: Split the Universe (2017 Apr 01)

Postby Chris Peterson » Sat Apr 15, 2017 3:36 pm

BDanielMayfield wrote:
neufer wrote:
BDanielMayfield wrote:Where in GR, in the macro world, is energy conservation violated?

Where in GR, in the macro world, are those multiple copies?

Nowhere. They don't exist in real spacetime. The supposed other universes are purely imaginary. We all live in the one real universe which we all effect by our actions as far as our individual spheres of influence extend.

We live in the real U, which is the sum of all paths actually taken by all mater and energy inside it, both animate and inanimate. The paths not taken are iUx, which are infinite but not real.

Maybe. But to be sure, these are philosophical assertions, not scientific ones.

(To the non math heads out there i is the imaginary number, the square root of negative one. As you cannot take the square root of a negative number the result isn't real, its imaginary. Imagine that.)

And yet, in a physical sense, i is entirely real, an essential element in a large number of equations that appear to accurately describe the workings of the universe in which we live. That is, it is only imaginary in the mathematical sense of the word, which is quite different than the everyday use, in which things like unicorns are imaginary.
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Re: APOD: Split the Universe (2017 Apr 01)

Postby BDanielMayfield » Sat Apr 15, 2017 4:20 pm

Chris Peterson wrote:
BDanielMayfield wrote:
neufer wrote:Where in GR, in the macro world, are those multiple copies?

Nowhere. They don't exist in real spacetime. The supposed other universes are purely imaginary. We all live in the one real universe which we all effect by our actions as far as our individual spheres of influence extend.

We live in the real U, which is the sum of all paths actually taken by all mater and energy inside it, both animate and inanimate. The paths not taken are iUx, which are infinite but not real.

Maybe. But to be sure, these are philosophical assertions, not scientific ones.

I'll take the "maybe" Chris. Philosophical assertions can be correct if they are based on reality.
(To the non math heads out there i is the imaginary number, the square root of negative one. As you cannot take the square root of a negative number the result isn't real, its imaginary. Imagine that.)

And yet, in a physical sense, i is entirely real, an essential element in a large number of equations that appear to accurately describe the workings of the universe in which we live. That is, it is only imaginary in the mathematical sense of the word, which is quite different than the everyday use, in which things like unicorns are imaginary.

Yes I was aware that there are real and necessary uses for i. Does my use of it fit here? If not, let's create a new term; lowercase italicized u, short for unicornian.

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Re: APOD: Split the Universe (2017 Apr 01)

Postby Chris Peterson » Sat Apr 15, 2017 4:59 pm

BDanielMayfield wrote:
Chris Peterson wrote:Maybe. But to be sure, these are philosophical assertions, not scientific ones.

I'll take the "maybe" Chris. Philosophical assertions can be correct if they are based on reality.

Of course, your suggestion that your philosophical statement is based on reality is itself a philosophical statement! ;)

And yet, in a physical sense, i is entirely real, an essential element in a large number of equations that appear to accurately describe the workings of the universe in which we live. That is, it is only imaginary in the mathematical sense of the word, which is quite different than the everyday use, in which things like unicorns are imaginary.

Yes I was aware that there are real and necessary uses for i. Does my use of it fit here? If not, let's create a new term; lowercase italicized u, short for unicornian.

I wasn't challenging your usage, just expanding on your comment.
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Re: APOD: Split the Universe (2017 Apr 01)

Postby geckzilla » Sat Apr 15, 2017 11:01 pm

What is this world coming to? Chris just used a bona fide emoticon.
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Re: APOD: Split the Universe (2017 Apr 01)

Postby Chris Peterson » Sat Apr 15, 2017 11:10 pm

geckzilla wrote:What is this world coming to? Chris just used a bona fide emoticon.

It was not my intent. I have emoticons disabled on my system, so any that I use are good old-fashioned ascii constructs. I guess the system must convert them for those who have them enabled.
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Re: APOD: Split the Universe (2017 Apr 01)

Postby geckzilla » Sat Apr 15, 2017 11:32 pm

Chris Peterson wrote:
geckzilla wrote:What is this world coming to? Chris just used a bona fide emoticon.

It was not my intent. I have emoticons disabled on my system, so any that I use are good old-fashioned ascii constructs. I guess the system must convert them for those who have them enabled.

I call the old-fashioned ascii constructs emoticon. They've always been called that, even before people started using image-based ones. Emojis, on the other hand...
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Re: APOD: Split the Universe (2017 Apr 01)

Postby neufer » Sun Apr 16, 2017 2:21 am

Chris Peterson wrote:
...conservation of energy is more of an observed principle than it is something with strong theoretical underpinnings.

Dark Energy is constantly increasing.

Kinetic energies of unbound particles (e.g., CMBR photons) are constantly decreasing.
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Re: APOD: Split the Universe (2017 Apr 01)

Postby BDanielMayfield » Sun Apr 16, 2017 1:15 pm

neufer wrote:
Chris Peterson wrote:
...conservation of energy is more of an observed principle than it is something with strong theoretical underpinnings.

Dark Energy is constantly increasing.

Kinetic energies of unbound particles (e.g., CMBR photons) are constantly decreasing.


Interesting cases Art. DE certainly looks real, but is it, really? Until it is explained it remains theoretical.

As mass is involved in Kinetic energy I don't understand how it relates to massless photons. I would like to though.

So then, the notion that "Energy can neither be created or destroyed" is a law of nature is apparently bogus. How about this equally hallowed principle: "For every action there is an equal and opposite reaction"? Is that bogus too when applied to these two cases? (Also, note that the changes in these two cases are opposite. Is there any chance that the cooling of the universe could be contributing energy toward its accelerating expansion :?:

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Re: APOD: Split the Universe (2017 Apr 01)

Postby Chris Peterson » Sun Apr 16, 2017 1:27 pm

BDanielMayfield wrote:
neufer wrote:
Chris Peterson wrote:...conservation of energy is more of an observed principle than it is something with strong theoretical underpinnings.

Dark Energy is constantly increasing.

Kinetic energies of unbound particles (e.g., CMBR photons) are constantly decreasing.

As mass is involved in Kinetic energy I don't understand how it relates to massless photons. I would like to though.

Keep in mind that photons are not really massless. They have energy, and therefore a mass equivalent. They also have momentum, which means a mass equivalent. The confusion likely comes from the understanding that a photon has zero rest mass. But that's a theoretical concept, given that a photon is never at rest.

While Art is correct that the kinetic energy of CMB photons is decreasing (because of redshift), this does not violate the law of conservation of energy, because kinetic energy is an observer dependent property- the kinetic energy we measure depends upon our frame of reference.
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Re: APOD: Split the Universe (2017 Apr 01)

Postby BDanielMayfield » Sun Apr 16, 2017 2:10 pm

Chris Peterson wrote:
BDanielMayfield wrote:As mass is involved in Kinetic energy I don't understand how it relates to massless photons. I would like to though.

Keep in mind that photons are not really massless. They have energy, and therefore a mass equivalent. They also have momentum, which means a mass equivalent. The confusion likely comes from the understanding that a photon has zero rest mass. But that's a theoretical concept, given that a photon is never at rest.

While Art is correct that the kinetic energy of CMB photons is decreasing (because of redshift), this does not violate the law of conservation of energy, because kinetic energy is an observer dependent property- the kinetic energy we measure depends upon our frame of reference.


That helps a lot. Thanks.

To be continued when I have more time ...
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