Fwd: Dan Dennett on AI

[Brent Meeker]

Why we shouldn't develop machines with general AI.

Brent


 Forwarded Message 

A contribution to a discussion we were having a couple of weeks ago:

https://www.wired.com/story/will-ai-achieve-consciousness-wrong-question/

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Re: Questions about the Equivalence Principle (EP) and GR

[Brent Meeker]

On 2/20/2019 1:23 PM, agrayson2...@gmail.com wrote:



On Wednesday, February 20, 2019 at 12:16:31 PM UTC-7, Brent wrote:



On 2/20/2019 8:42 AM, agrays...@gmail.com  wrote:



On Wednesday, February 20, 2019 at 7:09:10 AM UTC-7, John Clark
wrote:


>/Newton "explained" /


Why did you put explained in quotation marks? If you can
predict what something is going to do then you've explained
it, the better the prediction the better the explanation. I
don't know what else the word could possibly mean. And in
science no explanation is perfect, but some are less wrong
than others.


*QM better illustrates the justification for quotes. Many
interpretations that make the same predictions. AG *


/> why a body at "rest" can start moving, via the
application of "force"/


And Einstein explained that a body moving in a geodesic
through 4D spacetime will take a path that is not a geodesic
if a force is applied. The Earth is moving in a straight line
(aka a geodesic) through curved spacetime; the reason Earth's
orbit looks elliptical to us is due to map distortion, the
same reason that in a flat map of the curved surface of the
Earth Greenland looks larger than South America and is almost
as large as Africa. Except that it's even worse, in one we're
projecting the 2 D curved surface of the Earth into the flat
2D surface of the map, but with Einstein we're projecting a
curved 4D volume into a flat 3D volume.

/> What does "rest" mean in GR /


In General Relativity moving in a geodesic is as close as you
can get to the traditional idea of rest, but as long as time
passes you're going to be moving through 4D spacetime.


*If you're at spatial rest in spacetime in the presence of a
gravitational source, how does GR explain the subsequent spatial
motion? AG
*


When you were at "spatial rest" you had a force applied to you. 
Removing it allowed you to follow a geodesics path through
spacetimealso known as "falling".

Brent


*So it seems that GR doesn't explain motion; rather, it assumes motion 
is a natural state of things. AG

*


So called "standing still" is just motion in the time direction 
only...in Newtonian and special relativity as well. Just as there is no 
absolute motion, there's no absolution motionless either...it's called 
"relativity" for a reason.


Brent




/>  what causes "motion" from that pov?/


Force, same as with Newton.

John K Clark

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Re: Questions about the Equivalence Principle (EP) and GR

[agrayson2000]

On Wednesday, February 20, 2019 at 12:16:31 PM UTC-7, Brent wrote:
>
>
>
> On 2/20/2019 8:42 AM, agrays...@gmail.com  wrote:
>
>
>
> On Wednesday, February 20, 2019 at 7:09:10 AM UTC-7, John Clark wrote: 
>>
>>
>> >* Newton "explained" *
>>
>>
>> Why did you put explained in quotation marks? If you can predict what 
>> something is going to do then you've explained it, the better the 
>> prediction the better the explanation. I don't know what else the word 
>> could possibly mean. And in science no explanation is perfect, but some are 
>> less wrong than others.
>>
>
> *QM better illustrates the justification for quotes. Many interpretations 
> that make the same predictions. AG *
>
>>
>> *> why a body at "rest" can start moving, via the application of "force"*
>>
>>
>> And Einstein explained that a body moving in a geodesic through 4D 
>> spacetime will take a path that is not a geodesic if a force is applied. 
>> The Earth is moving in a straight line (aka a geodesic) through curved 
>> spacetime; the reason Earth's orbit looks elliptical to us is due to map 
>> distortion, the same reason that in a flat map of the curved surface of the 
>> Earth Greenland looks larger than South America and is almost as large as 
>> Africa. Except that it's even worse, in one we're projecting the 2 D 
>> curved surface of the Earth into the flat 2D surface of the map, but with 
>> Einstein we're projecting a curved 4D volume into a flat 3D volume. 
>>
>> *> What does "rest" mean in GR *
>>
>>
>> In General Relativity moving in a geodesic is as close as you can get to 
>> the traditional idea of rest, but as long as time passes you're going to be 
>> moving through 4D spacetime.
>>
>
>
> *If you're at spatial rest in spacetime in the presence of a gravitational 
> source, how does GR explain the subsequent spatial motion? AG *
>
>
> When you were at "spatial rest" you had a force applied to you.  Removing 
> it allowed you to follow a geodesics path through spacetimealso known 
> as "falling".
>
> Brent
>
>
*So it seems that GR doesn't explain motion; rather, it assumes motion is a 
natural state of things. AG *

>
>> *>  what causes "motion" from that pov?*
>>
>>
>> Force, same as with Newton.
>>
>> John K Clark
>>
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>
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Re: Questions about the Equivalence Principle (EP) and GR

[Brent Meeker]

On 2/20/2019 8:42 AM, agrayson2...@gmail.com wrote:



On Wednesday, February 20, 2019 at 7:09:10 AM UTC-7, John Clark wrote:


>/Newton "explained" /


Why did you put explained in quotation marks? If you can predict
what something is going to do then you've explained it, the better
the prediction the better the explanation. I don't know what else
the word could possibly mean. And in science no explanation is
perfect, but some are less wrong than others.


*QM better illustrates the justification for quotes. Many 
interpretations that make the same predictions. AG *



/> why a body at "rest" can start moving, via the application
of "force"/


And Einstein explained that a body moving in a geodesic through 4D
spacetime will take a path that is not a geodesic if a force is
applied. The Earth is moving in a straight line (aka a geodesic)
through curved spacetime; the reason Earth's orbit looks
elliptical to us is due to map distortion, the same reason that in
a flat map of the curved surface of the Earth Greenland looks
larger than South America and is almost as large as Africa. Except
that it's even worse, in one we're projecting the 2 D curved
surface of the Earth into the flat 2D surface of the map, but with
Einstein we're projecting a curved 4D volume into a flat 3D volume.

/> What does "rest" mean in GR /


In General Relativity moving in a geodesic is as close as you can
get to the traditional idea of rest, but as long as time passes
you're going to be moving through 4D spacetime.


*If you're at spatial rest in spacetime in the presence of a 
gravitational source, how does GR explain the subsequent spatial 
motion? AG

*


When you were at "spatial rest" you had a force applied to you. Removing 
it allowed you to follow a geodesics path through spacetimealso 
known as "falling".


Brent



/>  what causes "motion" from that pov?/


Force, same as with Newton.

John K Clark

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Re: Recommend this article, Even just for the Wheeler quote near the end

[Philip Thrift]

On Wednesday, February 20, 2019 at 9:14:35 AM UTC-6, PGC wrote:
>
>
>
> On Tuesday, February 19, 2019 at 11:39:21 PM UTC+1, Bruno Marchal wrote:
>>
>>
>> On 15 Feb 2019, at 20:43, Philip Thrift  wrote:
>>
>>
>>
>> On Friday, February 15, 2019 at 12:01:26 PM UTC-6, Bruno Marchal wrote:
>>>
>>>
>>> On 15 Feb 2019, at 16:12, Philip Thrift  wrote:
>>>
>>>
>>>
>>> On Friday, February 15, 2019 at 5:35:02 AM UTC-6, Bruno Marchal wrote:


 On 15 Feb 2019, at 08:25, Philip Thrift  wrote:

 On Wednesday, February 13, 2019 at 10:40:32 PM UTC-6, cdemorsella wrote:

> Two fascinating (and very different) approaches are presented to 
> derive Quantim Mechanics main practical tool (e.g. Born's rule). Wonder 
> what some of the physicists on here think about this research?
>
> I find the argument that no laws is the fundamental law... and that 
> the universe and its laws are emergent guided by subtle mathematical 
> statistical phenomena, at the same time both alluring and annoying it 
> is somehow unsatisfactory like being served a quite empty plate with 
> nice garnish for dinner.
>
> One example of emergence from chaotic conditions is how traffic jams 
> (aka density waves) can emerge from chaotic initial conditions, becoming 
> self re-enforcing within local domains of influence... for those unlucky 
> to 
> be stuck in them. Density wave emergence is seen across scale, for 
> example 
> the spiral arms of galaxies can be explained as giant gravitational pile 
> ups with some fundamentally similar parallels to say a rush hour traffic 
> jam, except on vastly different scales of course and due to other 
> different 
> factors, in the galactic case the emergent effects of a vast number of 
> gravitational inter-actions as stars migrate through these arms on their 
> grand voyages around the galactic core.
>
> This paired with the corollary argument that any attempt to discover a 
> fundamental law seems doomed to the infinite regression of then needing 
> to 
> explain what this foundation itself rests upon leading to the "it's 
> turtles all the way down" hall of mirrors carnival house... head-banger. 
>
> Perhaps, as Wheeler argued, the world is a self-synthesizing system, 
> and the seeming order we observe, is emergent... a law without law.
>
> Here is the link to the article:
>
>
> https://www.quantamagazine.org/the-born-rule-has-been-derived-from-simple-physical-principles-20190213/
>
>
  
 One can (sort of) write all "physics" in a couple of equations: the 
 Einstein Field Equation (EFE) and the Standard Model Equation (SME):

 EFE: 
 https://upload.wikimedia.org/wikipedia/commons/thumb/4/45/EinsteinLeiden4.jpg/620px-EinsteinLeiden4.jpg
 +
 SME: 
 https://www.sciencealert.com/images/Screen_Shot_2016-08-03_at_3.20.12_pm.png

 What caused *this particular arrangement* of expressions in these to 
 be the "law" of our universe I suppose can be "explained" by it's being 
 one 
 of any number of possible arrangements.



 The tiny (sigma_1) arithmetical reality contains all “combinations” of 
 all programs, and your explanation is a bit like digital physics, where 
 the 
 physical universe would be one special universal number, say U. That is 
 possible, but this can explain the origin of the physical laws, in a 
 coherent way with respect to the mind-body problem (the hard problem of 
 consciousness) only in presence of an explanation of why that program U is 
 winning, that is how such U can “multiply” you so much in the relative way 
 that the laws of physics get stabilised. Arithmetical self-reference 
 explains consciousness “easily”, but at the price of forcing us to derive 
 the physical laws from any universal machinery.
 The physical reality is not a mathematical reality among others, it is 
 the projective border of the universal mind, which is just the mind of the 
 universal machine. It is a complex many-dreams structure, and its quantum 
 aspects explain why negative amplitude of probability can play a role in 
 making the aberrant histories relatively rare, despite them being also in 
 that sigma_1 arithmetic.

 With mechanism, the idea that there is anything more than the sigma_1 
 arithmetical truth is absolutely undecidable. The sigma_1 truth emulates 
 the sigma_n believers for all n, and beyond. If the physics which is in 
 the 
 head of the universal numbers departs too much from what we see, it will 
 be 
 time to suspect that there is indeed something more. But not only there 
 are 
 no evidence for that, but there are strong evidence for the completeness 
 of 
 the sigma_1 truth with respect to the metaphysical questions.
>>

Re: Questions about the Equivalence Principle (EP) and GR

[Brent Meeker]

On 2/19/2019 11:06 PM, agrayson2...@gmail.com wrote:



On Tuesday, February 19, 2019 at 8:16:51 PM UTC-7, Brent wrote:



On 2/19/2019 5:10 PM, agrays...@gmail.com  wrote:


*What you wrote makes no sense. It fails to explain why motion
occurs in the absence of force. AG *


So did Newton: "A body in motion will remain in motion."


*Right, but Newton "explained" why a body at "rest" can start moving, 
via the application of "force".  What does "rest" mean in GR and what 
causes "motion" from that pov? *


Same thing.   Any body that have no forces on it is "at rest" in it's 
own frame, just like in Newtonian physics...except that gravity is no 
longer a force.   So free falling bodies are "at rest".


Brent

*Incidentally, when I posed the question of why space and time must be 
fused in relativity. I didn't know the answer. I came to a partial 
explanation by posing the question. AG*



Brent

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Re: Questions about the Equivalence Principle (EP) and GR

[John Clark]

On Wed, Feb 20, 2019 at 11:42 AM  wrote:

>
*> QM better illustrates the justification for quotes. Many interpretations
> that make the same predictions. AG *
>

Yes, many interpretations of Quantum Mechanics make the same predictions,
so at least for now which interpretation (explanation) you use is a matter
of taste. I hope someday we will know enough to be able to decide among
them. I like Many Worlds but that's just me

*> If you're at spatial rest in spacetime *
>

Then you're still moving through 4D spacetime

*> in the presence of a gravitational source,*
>

If I'm at spatial rest in the presence of a gravitational source then I'm
not on a geodesic path; I could be hovering 500 feet off the ground in a
rocket pushing me upward, and then the rocket stops and, since a force is
no longer operating, I'm back on a geodesic path until I reach the ground
and then the force of the ground provides a upward force again and I'm back
on a non geodesic path through spacetime, or at least the broken parts of
my body are.


> * > how does GR explain the subsequent spatial motion? AG *
>

I don't understand the question, if I'm at spatial rest how can I be at
spatial motion?

John K Clark

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Re: Questions about the Equivalence Principle (EP) and GR

[agrayson2000]

On Wednesday, February 20, 2019 at 7:09:10 AM UTC-7, John Clark wrote:
>
>
> >* Newton "explained" *
>
>
> Why did you put explained in quotation marks? If you can predict what 
> something is going to do then you've explained it, the better the 
> prediction the better the explanation. I don't know what else the word 
> could possibly mean. And in science no explanation is perfect, but some are 
> less wrong than others.
>

*QM better illustrates the justification for quotes. Many interpretations 
that make the same predictions. AG *

>
> *> why a body at "rest" can start moving, via the application of "force"*
>
>
> And Einstein explained that a body moving in a geodesic through 4D 
> spacetime will take a path that is not a geodesic if a force is applied. 
> The Earth is moving in a straight line (aka a geodesic) through curved 
> spacetime; the reason Earth's orbit looks elliptical to us is due to map 
> distortion, the same reason that in a flat map of the curved surface of the 
> Earth Greenland looks larger than South America and is almost as large as 
> Africa. 
> Except that it's even worse, in one we're projecting the 2 D curved surface 
> of the Earth into the flat 2D surface of the map, but with Einstein we're 
> projecting a curved 4D volume into a flat 3D volume. 
>
> *> What does "rest" mean in GR *
>
>
> In General Relativity moving in a geodesic is as close as you can get to 
> the traditional idea of rest, but as long as time passes you're going to be 
> moving through 4D spacetime.
>

*If you're at spatial rest in spacetime in the presence of a gravitational 
source, how does GR explain the subsequent spatial motion? AG *

>
> *>  what causes "motion" from that pov?*
>
>
> Force, same as with Newton.
>
> John K Clark
>

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Re: Recommend this article, Even just for the Wheeler quote near the end

[PGC]

On Tuesday, February 19, 2019 at 11:39:21 PM UTC+1, Bruno Marchal wrote:
>
>
> On 15 Feb 2019, at 20:43, Philip Thrift > 
> wrote:
>
>
>
> On Friday, February 15, 2019 at 12:01:26 PM UTC-6, Bruno Marchal wrote:
>>
>>
>> On 15 Feb 2019, at 16:12, Philip Thrift  wrote:
>>
>>
>>
>> On Friday, February 15, 2019 at 5:35:02 AM UTC-6, Bruno Marchal wrote:
>>>
>>>
>>> On 15 Feb 2019, at 08:25, Philip Thrift  wrote:
>>>
>>> On Wednesday, February 13, 2019 at 10:40:32 PM UTC-6, cdemorsella wrote:
>>>
 Two fascinating (and very different) approaches are presented to derive 
 Quantim Mechanics main practical tool (e.g. Born's rule). Wonder what some 
 of the physicists on here think about this research?

 I find the argument that no laws is the fundamental law... and that the 
 universe and its laws are emergent guided by subtle mathematical 
 statistical phenomena, at the same time both alluring and annoying it 
 is somehow unsatisfactory like being served a quite empty plate with 
 nice garnish for dinner.

 One example of emergence from chaotic conditions is how traffic jams 
 (aka density waves) can emerge from chaotic initial conditions, becoming 
 self re-enforcing within local domains of influence... for those unlucky 
 to 
 be stuck in them. Density wave emergence is seen across scale, for example 
 the spiral arms of galaxies can be explained as giant gravitational pile 
 ups with some fundamentally similar parallels to say a rush hour traffic 
 jam, except on vastly different scales of course and due to other 
 different 
 factors, in the galactic case the emergent effects of a vast number of 
 gravitational inter-actions as stars migrate through these arms on their 
 grand voyages around the galactic core.

 This paired with the corollary argument that any attempt to discover a 
 fundamental law seems doomed to the infinite regression of then needing to 
 explain what this foundation itself rests upon leading to the "it's 
 turtles all the way down" hall of mirrors carnival house... head-banger. 

 Perhaps, as Wheeler argued, the world is a self-synthesizing system, 
 and the seeming order we observe, is emergent... a law without law.

 Here is the link to the article:


 https://www.quantamagazine.org/the-born-rule-has-been-derived-from-simple-physical-principles-20190213/


>>>  
>>> One can (sort of) write all "physics" in a couple of equations: the 
>>> Einstein Field Equation (EFE) and the Standard Model Equation (SME):
>>>
>>> EFE: 
>>> https://upload.wikimedia.org/wikipedia/commons/thumb/4/45/EinsteinLeiden4.jpg/620px-EinsteinLeiden4.jpg
>>> +
>>> SME: 
>>> https://www.sciencealert.com/images/Screen_Shot_2016-08-03_at_3.20.12_pm.png
>>>
>>> What caused *this particular arrangement* of expressions in these to be 
>>> the "law" of our universe I suppose can be "explained" by it's being one of 
>>> any number of possible arrangements.
>>>
>>>
>>>
>>> The tiny (sigma_1) arithmetical reality contains all “combinations” of 
>>> all programs, and your explanation is a bit like digital physics, where the 
>>> physical universe would be one special universal number, say U. That is 
>>> possible, but this can explain the origin of the physical laws, in a 
>>> coherent way with respect to the mind-body problem (the hard problem of 
>>> consciousness) only in presence of an explanation of why that program U is 
>>> winning, that is how such U can “multiply” you so much in the relative way 
>>> that the laws of physics get stabilised. Arithmetical self-reference 
>>> explains consciousness “easily”, but at the price of forcing us to derive 
>>> the physical laws from any universal machinery.
>>> The physical reality is not a mathematical reality among others, it is 
>>> the projective border of the universal mind, which is just the mind of the 
>>> universal machine. It is a complex many-dreams structure, and its quantum 
>>> aspects explain why negative amplitude of probability can play a role in 
>>> making the aberrant histories relatively rare, despite them being also in 
>>> that sigma_1 arithmetic.
>>>
>>> With mechanism, the idea that there is anything more than the sigma_1 
>>> arithmetical truth is absolutely undecidable. The sigma_1 truth emulates 
>>> the sigma_n believers for all n, and beyond. If the physics which is in the 
>>> head of the universal numbers departs too much from what we see, it will be 
>>> time to suspect that there is indeed something more. But not only there are 
>>> no evidence for that, but there are strong evidence for the completeness of 
>>> the sigma_1 truth with respect to the metaphysical questions.
>>>
>>> Bruno 
>>>
>>>
>>>
>>>
>> Whatever brand of scientist - physicist, chemist, biologist, even 
>> psychologist - it seems that they see any theory of whatever is within 
>> their domain is to be composed of a fi

Re: Questions about the Equivalence Principle (EP) and GR

[John Clark]

> >* Newton "explained" *


Why did you put explained in quotation marks? If you can predict what
something is going to do then you've explained it, the better the
prediction the better the explanation. I don't know what else the word
could possibly mean. And in science no explanation is perfect, but some are
less wrong than others.

*> why a body at "rest" can start moving, via the application of "force"*


And Einstein explained that a body moving in a geodesic through 4D
spacetime will take a path that is not a geodesic if a force is applied.
The Earth is moving in a straight line (aka a geodesic) through curved
spacetime; the reason Earth's orbit looks elliptical to us is due to map
distortion, the same reason that in a flat map of the curved surface of the
Earth Greenland looks larger than South America and is almost as large
as Africa.
Except that it's even worse, in one we're projecting the 2 D curved surface
of the Earth into the flat 2D surface of the map, but with Einstein we're
projecting a curved 4D volume into a flat 3D volume.

*> What does "rest" mean in GR *


In General Relativity moving in a geodesic is as close as you can get to
the traditional idea of rest, but as long as time passes you're going to be
moving through 4D spacetime.

*>  what causes "motion" from that pov?*


Force, same as with Newton.

John K Clark

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Re: Questions about the Equivalence Principle (EP) and GR

[agrayson2000]

On Wednesday, February 20, 2019 at 12:30:01 AM UTC-7, Philip Thrift wrote:
>
>
>
> On Wednesday, February 20, 2019 at 1:06:25 AM UTC-6, agrays...@gmail.com 
> wrote:
>>
>>
>>
>> On Tuesday, February 19, 2019 at 8:16:51 PM UTC-7, Brent wrote:
>>>
>>>
>>>
>>> On 2/19/2019 5:10 PM, agrays...@gmail.com wrote:
>>>
>>>
>>> *What you wrote makes no sense. It fails to explain why motion occurs in 
>>> the absence of force. AG *
>>>
>>>
>>> So did Newton: "A body in motion will remain in motion."
>>>
>>
>> *Right, but Newton "explained" why a body at "rest" can start moving, via 
>> the application of "force".  What does "rest" mean in GR and what causes 
>> "motion" from that pov? Incidentally, when I posed the question of why 
>> space and time must be fused in relativity. I didn't know the answer. I 
>> came to a partial explanation by posing the question. AG*
>>
>>>
>>>
>
> Physics doesn't really explain anything. It only creates expressions in 
> different mathematical dialects that we interpret.
>

*Right. That's why I put the quotes around *explained*. AG *

>
>
> https://www.newyorker.com/science/elements/a-different-kind-of-theory-of-everything
>  
>
>
> In 1964, during a lecture at Cornell University, the physicist Richard 
> Feynman articulated a profound mystery about the physical world. He told 
> his listeners to imagine two objects, each gravitationally attracted to the 
> other. How, he asked, should we predict their movements? Feynman identified 
> three approaches, each invoking a different belief about the world. The 
> first approach used Newton’s law of gravity, according to which the objects 
> exert a pull on each other. The second imagined a gravitational field 
> extending through space, which the objects distort. The third applied the 
> principle of least action, which holds that each object moves by following 
> the path that takes the least energy in the least time. All three 
> approaches produced the same, correct prediction. They were three equally 
> useful descriptions of how gravity works.
>

*Except that it's wrong to put Newton's gravity theory on the same level as 
Einstein's. Also, I think we can dispense with the Principle of Least 
Action and just use the geodesic hypothesis as a postulate of GR.  We could 
say that God preferred a unique path, the extremal, rather than having to 
choose among an uncountable set of paths for each path between distinct 
events in the manifold. AG*

>
> “One of the amazing characteristics of nature is this variety of 
> interpretational schemes,” Feynman said. ... “If you modify the laws much, 
> you find you can only write them in fewer ways,” Feynman said. “I always 
> found that mysterious, and I do not know the reason why it is that the 
> correct laws of physics are expressible in such a tremendous variety of 
> ways. They seem to be able to get through several wickets at the same time.”
>
> ...
>
> - pt
>

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