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Re: QM and GR.

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  Re: QM and GR. Tom Roberts <tjroberts137@sbcglobal.net> - 2016-07-22 22:39 -0500
    Re: QM and GR. Thomas Heger <ttt_heg@web.de> - 2016-07-23 08:14 +0200
      Re: QM and GR. Odd Bodkin <bodkinodd@gmail.com> - 2016-07-23 10:43 -0500
        Re: QM and GR. "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-07-23 13:29 -0700
          Re: QM and GR. benj <benj@nobody.net> - 2016-07-23 17:24 -0400
            Re: QM and GR. "Y.Porat" <y.y.porat@gmail.com> - 2016-07-25 05:00 -0700
      Re: QM and GR. Tom Roberts <tjroberts137@sbcglobal.net> - 2016-07-23 12:33 -0500
        Re: QM and GR. Thomas Heger <ttt_heg@web.de> - 2016-07-23 22:41 +0200
          Re: QM and GR. Thomas Heger <ttt_heg@web.de> - 2016-07-24 07:12 +0200
          Re: QM and GR. Thomas Heger <ttt_heg@web.de> - 2016-07-26 09:21 +0200
        Re: QM and GR. Thomas Heger <ttt_heg@web.de> - 2016-07-27 07:11 +0200
      Re: QM and GR. edprochak@gmail.com - 2016-07-25 10:11 -0700
    Re: QM and GR. Sylvia Else <sylvia@not.at.this.address> - 2016-07-25 16:45 +1000
      Re: QM and GR. Sylvia Else <sylvia@not.at.this.address> - 2016-07-25 16:46 +1000
      Re: QM and GR. Poutnik <poutnik4nntp@gmail.com> - 2016-07-25 11:08 +0200
      Re: QM and GR. Tom Roberts <tjroberts137@sbcglobal.net> - 2016-07-25 12:28 -0500
        that & this noTthaTguY <abu.kuanysh05@gmail.com> - 2016-07-25 19:46 -0700
          Re: that & this noTthaTguY <abu.kuanysh05@gmail.com> - 2016-07-28 19:21 -0700
        Re: QM and GR. wugi <brol@brol.be> - 2016-07-26 12:11 +0200
          Re: QM and GR. Tom Roberts <tjroberts137@sbcglobal.net> - 2016-07-27 12:11 -0500
            Re: QM and GR. Thomas Heger <ttt_heg@web.de> - 2016-07-29 10:20 +0200
              Re: QM and GR. Odd Bodkin <bodkinodd@gmail.com> - 2016-07-29 07:13 -0500
              so sad, that M. is known only for his slogan about a mere phase-space noTthaTguY <abu.kuanysh05@gmail.com> - 2016-07-29 09:03 -0700
                lightcone(s brandonahenley9@gmail.com - 2016-07-29 12:18 -0700
              Re: The rate at which the time axis grows, relative to the spatial dimensions. Adlbifhr Mjduhgfks <am@random.us> - 2016-08-07 15:36 +0000
              Re: The rate at which the time axis grows, relative to the spatial dimensions. Tom Roberts <tjroberts137@sbcglobal.net> - 2016-08-07 12:31 -0500
                Re: The rate at which the time axis grows, relative to the spatial dimensions. chrisv <chrisv@nospam.invalid> - 2016-08-08 06:57 -0500
              Re: The rate at which the time axis grows, relative to the spatial dimensions. Thomas Heger <ttt_heg@web.de> - 2016-08-08 07:18 +0200
                Re: _Nothing_ can change the future, present or past. The Starmaker <starmaker@ix.netcom.com> - 2016-08-08 11:02 -0700
                  Re: _Nothing_ can change the future, present or past. chrisv <chrisv@nospam.invalid> - 2016-08-08 13:14 -0500
                  Re: _Nothing_ can change the future, present or past. Double-A <double-a3@hush.com> - 2016-08-08 13:07 -0700
                Re: _Nothing_ can change the future, present or past. Double-A <double-a3@hush.com> - 2016-08-08 13:05 -0700
                Re: _Nothing_ can change the future, present or past. Thomas Heger <ttt_heg@web.de> - 2016-08-08 22:52 +0200
                  Re: _Nothing_ can change the future, present or past. noTthaTguY <abu.kuanysh05@gmail.com> - 2016-08-08 15:11 -0700
                  Re: Nature decides _everything_. Thomas Heger <ttt_heg@web.de> - 2016-08-09 08:42 +0200
                    Re: Nature programmed you to choose one over the other. The Starmaker <starmaker@ix.netcom.com> - 2016-08-09 12:09 -0700
                      Re: Nature programmed you to choose one over the other. noTthaTguY <abu.kuanysh05@gmail.com> - 2016-08-09 12:54 -0700
                      Re: Nature programmed you to choose one over the other. The Starmaker <starmaker@ix.netcom.com> - 2016-08-09 13:35 -0700
                        Re: Nature programmed you to choose one over the other. noTthaTguY <abu.kuanysh05@gmail.com> - 2016-08-09 13:38 -0700
                        Re: Nature programmed you to choose one over the other. Thomas Heger <ttt_heg@web.de> - 2016-08-09 23:53 +0200
                          da tum noTthaTguY <abu.kuanysh05@gmail.com> - 2016-08-19 11:06 -0700
                      Re: Nature programmed you to choose one over the other. benj <benj@nobody.net> - 2016-08-09 18:17 -0400
                  Re: _Nothing_ can change the future, present or past. chrisv <chrisv@nospam.invalid> - 2016-08-09 06:51 -0500
                    Re: _Nothing_ can change the future, present or past. benj <benj@nobody.net> - 2016-08-09 17:51 -0400
                  Re: Nature decides _everything_. Double-A <double-a3@hush.com> - 2016-08-09 14:40 -0700

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#590422 — Re: QM and GR.

On 7/16/16 7/16/16   12:31 AM, Sylvia Else wrote:
> There cannot be two different correct theories, because if they're different,
> they'll sometimes give different answers, and at least one would have to be wrong.

Sure there can, as long as they predict the same result(s) for the experiments.

Newtonian, Lagrangian, and Hamiltonian mechanics are all quite different 
theories, yet they all predict exactly the same result for any experiment within 
their domain (which is common to all).

Closer to this newsgroup, SR and LET are quite different theories, yet they 
predict the same results for any experiment within their common domain.

But the situation is quite different for QM and GR -- they are each valid in 
their own domain, and these domains do not overlap significantly. Moreover, the 
union of their domains does not include all possible phenomena. As nature 
"works" for all phenomena in all domains, there must be some theory that can 
model her behavior in all domains, including the domains of QM and GR and the 
additional domain(s) not covered by either.

Yes, as you say this new theory must have appropriate limits that reduce to QM 
and GR in their respective domains.

	Actually that is a bit stronger than the real requirement, which
	is that this new theory agree with all experiments in the domains
	of QM and GR. As those theories agree with all experiments within
	their domains, the traditional way to do that is to have an
	appropriate correspondence limit, but that is not the only
	conceivable way....


Tom Roberts

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#590439

Am 23.07.2016 05:39, schrieb Tom Roberts:

>> There cannot be two different correct theories, because if they're
>> different,
>> they'll sometimes give different answers, and at least one would have
>> to be wrong.
>
> Sure there can, as long as they predict the same result(s) for the
> experiments.
>
> Newtonian, Lagrangian, and Hamiltonian mechanics are all quite different
> theories, yet they all predict exactly the same result for any
> experiment within their domain (which is common to all).
>
> Closer to this newsgroup, SR and LET are quite different theories, yet
> they predict the same results for any experiment within their common
> domain.
>
> But the situation is quite different for QM and GR -- they are each
> valid in their own domain, and these domains do not overlap
> significantly. Moreover, the union of their domains does not include all
> possible phenomena. As nature "works" for all phenomena in all domains,
> there must be some theory that can model her behavior in all domains,
> including the domains of QM and GR and the additional domain(s) not
> covered by either.
>
> Yes, as you say this new theory must have appropriate limits that reduce
> to QM and GR in their respective domains.
>
> Actually that is a bit stronger than the real requirement, which
> is that this new theory agree with all experiments in the domains
> of QM and GR. As those theories agree with all experiments within
> their domains, the traditional way to do that is to have an
> appropriate correspondence limit, but that is not the only
> conceivable way....
>

As far as we know, nature behaves unpredictable.

E.g. we cannot predict the path, a certain fly would take.

So, why should nature like to predict experiments?

I would exclude the requirement of usefulness (as means of predictions) 
for a valid theory about how nature behaves at a fundamental level.

Instead it should be simple, since nature would not use too many 
different entities, but infinite variations of the same in different 
manners.

The best theory possible would use only one something, that is observed 
in various guises, as stuff, fields or empty space.

TH


TH

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#590453

On 7/23/2016 1:14 AM, Thomas Heger wrote:
>
> As far as we know, nature behaves unpredictable.
>
> E.g. we cannot predict the path, a certain fly would take.

Because we do not have a good understanding of how a fly works.

>
> So, why should nature like to predict experiments?
>
> I would exclude the requirement of usefulness (as means of predictions)
> for a valid theory about how nature behaves at a fundamental level.

But this is central to the scientific method. It is THE sole way that 
the validity of our scientific understanding is asserted. So you are 
saying that you want to dispense with the scientific method.

>
> Instead it should be simple, since nature would not use too many
> different entities, but infinite variations of the same in different
> manners.
>
> The best theory possible would use only one something, that is observed
> in various guises, as stuff, fields or empty space.

While this is a lofty philosophical stance, it has little to do with 
science. What scientists have shown is that nature is inherently simple, 
but only as simple as necessary. To desire to drive nature to be simpler 
than it is, is folly.


-- 
Odd Bodkin --- maker of fine toys, tools, tables

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#590476

On Saturday, July 23, 2016 at 8:43:06 AM UTC-7, Odd Bodkin wrote:
> On 7/23/2016 1:14 AM, Thomas Heger wrote:
> >
> > As far as we know, nature behaves unpredictable.
> >
> > E.g. we cannot predict the path, a certain fly would take.
> 
> Because we do not have a good understanding of how a fly works.
> 
> >
> > So, why should nature like to predict experiments?
> >
> > I would exclude the requirement of usefulness (as means of predictions)
> > for a valid theory about how nature behaves at a fundamental level.
> 
> But this is central to the scientific method. It is THE sole way that 
> the validity of our scientific understanding is asserted. So you are 
> saying that you want to dispense with the scientific method.
> 
> >
> > Instead it should be simple, since nature would not use too many
> > different entities, but infinite variations of the same in different
> > manners.
> >
> > The best theory possible would use only one something, that is observed
> > in various guises, as stuff, fields or empty space.
> 
> While this is a lofty philosophical stance, it has little to do with 
> science. What scientists have shown is that nature is inherently simple, 
> but only as simple as necessary. To desire to drive nature to be simpler 
> than it is, is folly.
> 
> 
> -- 
> Odd Bodkin --- maker of fine toys, tools, tables

Nature is inherently simple,but it hides lots of stuff very well.Think source of gravity.Think double slits.Think c  TreBert

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#590491

On 7/23/2016 4:29 PM, reber g=emc^2 wrote:
> On Saturday, July 23, 2016 at 8:43:06 AM UTC-7, Odd Bodkin wrote:
>> On 7/23/2016 1:14 AM, Thomas Heger wrote:
>>>
>>> As far as we know, nature behaves unpredictable.
>>>
>>> E.g. we cannot predict the path, a certain fly would take.
>>
>> Because we do not have a good understanding of how a fly works.
>>
>>>
>>> So, why should nature like to predict experiments?
>>>
>>> I would exclude the requirement of usefulness (as means of predictions)
>>> for a valid theory about how nature behaves at a fundamental level.
>>
>> But this is central to the scientific method. It is THE sole way that
>> the validity of our scientific understanding is asserted. So you are
>> saying that you want to dispense with the scientific method.
>>
>>>
>>> Instead it should be simple, since nature would not use too many
>>> different entities, but infinite variations of the same in different
>>> manners.
>>>
>>> The best theory possible would use only one something, that is observed
>>> in various guises, as stuff, fields or empty space.
>>
>> While this is a lofty philosophical stance, it has little to do with
>> science. What scientists have shown is that nature is inherently simple,
>> but only as simple as necessary. To desire to drive nature to be simpler
>> than it is, is folly.
>>
>>
>> --
>> Odd Bodkin --- maker of fine toys, tools, tables
>
> Nature is inherently simple,but it hides lots of stuff very well.Think source of gravity.Think double slits.Think c  TreBert
>
Boinker, nature is simple. Note how a single photon goes through two 
slits at once! That is because photons are always in pairs. That is a 
given! See how simple things are when explained the right way?

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#590667

On Sunday, July 24,  > >>
> >>
> >> --
> >> Odd Bodkin --- maker of fine toys, tools, tables
> >
> > Nature is inherently simple,but it hides lots of stuff very well.Think source of gravity.Think double slits.Think c  TreBert
> >
> Boinker, nature is simple. Note how a single photon goes through two 
> slits at once! That is because photons are always in pairs. That is a 
> given! See how simple things are when explained the right way?

======================
had  physics' been not been blockhead parrots 
hey could understand that
E=h f
IS NOT THE ENERGY OF A SINLE PHOTON
BUT
A HUGE BUNDLE OF SIMGLE  PHOTONS !! 
f is one second defined 
while
experimentally we see that
photon energy can be emitted
during even during 
to fractions of a second !!
-
physicists pose to be intelligent people
yet  it seems that they are 
 unbelievable retarded monkey parrots !!! 
====
Y.Porat

==========================================

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#590464

On 7/23/16 7/23/16   1:14 AM, Thomas Heger wrote:
> As far as we know, nature behaves unpredictable.

NONSENSE! Mostly nature behaves very predictably. We have excellent models that 
have great predictive power over large domains of interest to us.

	However it is true that in the quantum domain there is
	considerable randomness. Usually for macroscopic objects
	this randomness averages away....


> E.g. we cannot predict the path, a certain fly would take.

You confuse complexity with unpredictability. A fly is FAR too complex for our 
models of nature to be applied. But there are lots of situations for which we 
can accurately predict how an individual atom will behave....


Tom Roberts

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#590480

Am 23.07.2016 19:33, schrieb Tom Roberts:
  :
>> As far as we know, nature behaves unpredictable.
>
> NONSENSE! Mostly nature behaves very predictably. We have excellent
> models that have great predictive power over large domains of interest
> to us.
>
> However it is true that in the quantum domain there is
> considerable randomness. Usually for macroscopic objects
> this randomness averages away....
>
>
>> E.g. we cannot predict the path, a certain fly would take.
>
> You confuse complexity with unpredictability. A fly is FAR too complex
> for our models of nature to be applied. But there are lots of situations
> for which we can accurately predict how an individual atom will behave....
>

No. I want to express, that the input into a system, which we try to 
model, is not known completely.

This is so, because we have only access to a subset of all influences, 
that have an impact on the outcome of something.

E.g. we would like to predict the path of a floating ball. This is a 
large plastic ball and there are two kids inside. They pay a few Euros 
for half an hour inside this ball.

The path is unpredictable, since we cannot know, what these kids are doing.

Or we cannot know, how the wind would blow in the future.

And all sort of other things we cannot know. So we have no chance to 
predict, what will happen to this ball.

Predictability is restricted to very simple cases.

But even in extremely simple case, there could be influences from 
unexpected sides and things go other ways than we predict.

But that's not bad at all. Only the expectations should be a little 
lower than to predict the future.


TH

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#590552

Am 23.07.2016 22:41, schrieb Thomas Heger:
> Am 23.07.2016 19:33, schrieb Tom Roberts:
> :
>>> As far as we know, nature behaves unpredictable.
>>
>> NONSENSE! Mostly nature behaves very predictably. We have excellent
>> models that have great predictive power over large domains of interest
>> to us.
>>
>> However it is true that in the quantum domain there is
>> considerable randomness. Usually for macroscopic objects
>> this randomness averages away....
>>
>>
>>> E.g. we cannot predict the path, a certain fly would take.
>>
>> You confuse complexity with unpredictability. A fly is FAR too complex
>> for our models of nature to be applied. But there are lots of situations
>> for which we can accurately predict how an individual atom will
>> behave....
>>
>
> No. I want to express, that the input into a system, which we try to
> model, is not known completely.
>
> This is so, because we have only access to a subset of all influences,
> that have an impact on the outcome of something.
>
> E.g. we would like to predict the path of a floating ball. This is a
> large plastic ball and there are two kids inside. They pay a few Euros
> for half an hour inside this ball.
>
> The path is unpredictable, since we cannot know, what these kids are doing.
>
> Or we cannot know, how the wind would blow in the future.
>
> And all sort of other things we cannot know. So we have no chance to
> predict, what will happen to this ball.
>
> Predictability is restricted to very simple cases.
>
> But even in extremely simple case, there could be influences from
> unexpected sides and things go other ways than we predict.
>
> But that's not bad at all. Only the expectations should be a little
> lower than to predict the future.
>


'To measure' means, that a process is conducted, by which we refer to 
shape, size and behaviour of a system (in the macroscopic realm).

But nature does not support this kind of measurements, since natural 
systems are based on infinite variations of similar principles.

Example:  we grow a plant, say a tree.

With endless variations all trees look different, but somehow similar, 
even if they would stem from the same seed.

This is so because macroscopic shape is a function of a multitude of 
tiny entities, which have themselves no idea of macroscopic shape.

This is similar to clouds: clouds are composed from air and 
water-droplets. But the drops have no intention to create a specific 
shape of the cloud.

So all clouds look different.

This would not say, that drops are different and behave in different 
manners. Only size and shape could have variations, what makes 
macroscopic forms unpredictable.

So natural systems behave from inside to outside. And the larger forms 
are an overlay of smaller forms. And this goes up and down very far.

What we call 'macroscopic shape' is actually a certain level of a larger 
picture, which corresponds to the level we as humans beings have in 
respect to our own environment.

This may be our own preferred realm of measurements and where we would 
like to predict things. But nature has other plans, rather than to 
provide us with information about the future.

TH

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#590796

Am 23.07.2016 22:41, schrieb Thomas Heger:

>>> As far as we know, nature behaves unpredictable.
>>
>> NONSENSE! Mostly nature behaves very predictably. We have excellent
>> models that have great predictive power over large domains of interest
>> to us.
>>
>> However it is true that in the quantum domain there is
>> considerable randomness. Usually for macroscopic objects
>> this randomness averages away....
>>
>>
>>> E.g. we cannot predict the path, a certain fly would take.
>>
>> You confuse complexity with unpredictability. A fly is FAR too complex
>> for our models of nature to be applied. But there are lots of situations
>> for which we can accurately predict how an individual atom will
>> behave....
>>


Quantum mechanics is actually responsible for predictions in the realm 
of the very small items, like atoms and particles.

But QM uses statistical methods as main tool and has invented the 
'uncertainty principle', to express the impossibility to do, what you 
believe they actually can.

Actually QM can NOT predict the path of an individual particle or atom.

One reason: particles are not individuals.

IOW: you cannot number particles and find the same particle under the 
same number again.

And if you do and try to confine the realm of investigation to a 
specific particle, the uncertainty principle comes into play.




> No. I want to express, that the input into a system, which we try to
> model, is not known completely.
>
> This is so, because we have only access to a subset of all influences,
> that have an impact on the outcome of something.


If you take a certain spot and calculate, to which form all influences 
onto this point would overlap in the future, you would obviously need to 
estimate all possible influences.

Only you cannot do this, since only a subset of what is possible in 
principle is known and could be measured.

But e.g. neutrinos are hard to measure, but may eventually have an impact.

So you are obliged to restrict the model to simple cases, where most of 
the influences are known and under control.

Only this is not, what we usually want to measure and what predictions 
are about.

Predictions are from the realm, we have interest in and that is our 
usual scale in the macroscopic range.

But macroscopic systems contain really large amounts of smaller items 
and these small entities are actually, what drives the process, we try 
to model.

The overall shape is of no particular interest (for these small items) 
since they simply to not know.

So we want to predict, what is actually generated by statistical 
processes. And that will not work.

TH

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#590893

Am 23.07.2016 19:33, schrieb Tom Roberts:

>> As far as we know, nature behaves unpredictable.
>
> NONSENSE! Mostly nature behaves very predictably. We have excellent
> models that have great predictive power over large domains of interest
> to us.
>
> However it is true that in the quantum domain there is
> considerable randomness. Usually for macroscopic objects
> this randomness averages away....


If an object behaves randomly only at the particle level, but is 'clean' 
on the macroscopic level, then randomness from the particles would 
average out.


This would only be the case, if the environment is also 'clean' and 
under tight control.

Such states are not that common in the real world, since common objects 
in common environments are subject to randomness of this environment.

Usually things age, get broken, rot, oxidise and so forth.

This is usually ascribed to age and second law of thermodynamics, but is 
actually the influence of the realm, we cannot control.

So you demand to predict such cases, where we have no randomness in the 
macroscopic realm, since in certain cases, we have only influences, we 
know about.

But usually we know not enough, since influences come usually from an 
area, which is invisible.

In a spacetime-view, the things visible are events on our past light 
cone. The things, that could eventually have an influence could stem 
from the the entire past semi-ball, which is past an event.

So in effect we can know only a few percent of what is actually there 
and more than 90% is invisible, but 'there'.

Future is actually like 'sum of all possible path' and all possible 
things add up to the next step in time for a certain system.

If we want to predict the outcome, we must know all possible inputs.

But we cannot know, since we have access only to a certain subset of 
possible influences.

So we could only enlarge the area of control far enough, that no 
unwanted disturbance occurs. Than we make the thing in question VERY 
clean and pure and then we could predict it.

>> E.g. we cannot predict the path, a certain fly would take.
>
> You confuse complexity with unpredictability. A fly is FAR too complex
> for our models of nature to be applied. But there are lots of situations
> for which we can accurately predict how an individual atom will behave....

As a matter of fact, our current models would not allow flies to fly at 
all.


TH

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#590696

On Saturday, July 23, 2016 at 2:14:59 AM UTC-4, Thomas Heger wrote:
> Am 23.07.2016 05:39, schrieb Tom Roberts:
> 
[]
> >
> > Yes, as you say this new theory must have appropriate limits that reduce
> > to QM and GR in their respective domains.
> >
> > Actually that is a bit stronger than the real requirement, which
> > is that this new theory agree with all experiments in the domains
> > of QM and GR. As those theories agree with all experiments within
> > their domains, the traditional way to do that is to have an
> > appropriate correspondence limit, but that is not the only
> > conceivable way....
> >
> 
> As far as we know, nature behaves unpredictable.
> 
> E.g. we cannot predict the path, a certain fly would take.
> 
> So, why should nature like to predict experiments?

Not sure of your point here. Nature doesn't predict. It just acts.

> 
> I would exclude the requirement of usefulness (as means of predictions) 
> for a valid theory about how nature behaves at a fundamental level.

Then what would you have left? If I cannot use the theory to make
predictions, then I cannot build a plane that flies or even a decent
pair of prescription glasses. Pretty poor theory that says nothing useful.
might as well go with the invisible crocodile theory.

> 
> Instead it should be simple, since nature would not use too many 
> different entities, but infinite variations of the same in different 
> manners.

Yes, as Einstein said "as simple as possible, but no simpler"

> 
> The best theory possible would use only one something, that is observed 
> in various guises, as stuff, fields or empty space.
> 

It would be nice if all things could be explained as different
properties of one entity. We just aren't there yet. maybe in another
100,000 years.

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#590658

On 23/07/2016 1:39 PM, Tom Roberts wrote:
> On 7/16/16 7/16/16   12:31 AM, Sylvia Else wrote:
>> There cannot be two different correct theories, because if they're
>> different,
>> they'll sometimes give different answers, and at least one would have
>> to be wrong.
>
> Sure there can, as long as they predict the same result(s) for the
> experiments.
>
> Newtonian, Lagrangian, and Hamiltonian mechanics are all quite different
> theories, yet they all predict exactly the same result for any
> experiment within their domain (which is common to all).

I'd tend to regard them as different manifestations of the same 
underlying theory.

>
> Closer to this newsgroup, SR and LET are quite different theories, yet
> they predict the same results for any experiment within their common
> domain.

They are mathematically the same. LET is just derived differently, based 
on the assumption of something that the theory doesn't include, and 
doesn't describe.

Sylvia.

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#590659

On 25/07/2016 4:45 PM, Sylvia Else wrote:
>
> I'd tend to regard them as different manifestations of the same
> underlying theory.

"formulations" is more appropriate word than "manifestations".

Sylvia.

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#590665

On 07/25/2016 08:45 AM, Sylvia Else wrote:
> On 23/07/2016 1:39 PM, Tom Roberts wrote:
>>
>> Sure there can, as long as they predict the same result(s) for the
>> experiments.
>>
>> Newtonian, Lagrangian, and Hamiltonian mechanics are all quite different
>> theories, yet they all predict exactly the same result for any
>> experiment within their domain (which is common to all).
>
> I'd tend to regard them as different manifestations of the same
> underlying theory.

But a theory is a model. Different theories/models
cannot be different formulations of the unknown model.
There can exist different interpretations of the same known model.

It can later come ( and often comes ) a model, that unifies
the previous models, or one of models is abandoned
having unnecessery assumptions, narrower scope,
or they are distinguished later by not yet known phenomena.
>
>>
>> Closer to this newsgroup, SR and LET are quite different theories, yet
>> they predict the same results for any experiment within their common
>> domain.
>
> They are mathematically the same. LET is just derived differently, based
> on the assumption of something that the theory doesn't include, and
> doesn't describe.
>
Being equivalent does not mean being the same,
what is not limited neither to theories neither to physics.

Like there is several very different yet equivalent formulations
of the 2nd law of thermodynamics.

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#590698

On 7/25/16 7/25/16 - 1:45 AM, Sylvia Else wrote:
> On 23/07/2016 1:39 PM, Tom Roberts wrote:
>> Newtonian, Lagrangian, and Hamiltonian mechanics are all quite different
>> theories, yet they all predict exactly the same result for any
>> experiment within their domain (which is common to all).
>
> I'd tend to regard them as different manifestations of the same underlying theory.

OK, let's be more careful. To me a physical theory consist of:
   1. A set of postulates (aka axioms) and theorems derived from them.
   2. A set of definitions for the meaning of every symbol in #1.

Two theories are "the same" if their #1 and #2 are both identical sets. Note 
that in #1 the distinction between postulate and theorem disappears, and any 
sufficient set of postulates will yield the same theory.

In this sense, Newtonian, Lagrangian, and Hamiltonian mechanics are indeed all 
the same theory.


>> Closer to this newsgroup, SR and LET are quite different theories, yet
>> they predict the same results for any experiment within their common
>> domain.
>
> They are mathematically the same. LET is just derived differently, based on the
> assumption of something that the theory doesn't include, and doesn't describe.

Not in the above sense. LET starts out with a postulate "There is an ether which 
is at rest in a unique inertial frame." -- that does not appear in SR, so they 
are NOT the same theory. Indeed there are lots of theorems in LET that do not 
appear in SR; these two theories always give the same predictions for 
MEASUREMENTS, but not for internal calculations [#].

	[#] E.g. in LET the vacuum speed of light is isotropically c
	only in the ether frame, but MEASUREMENTS of its speed will
	yield c in any inertial frame. This happens because the
	behavior of REAL clocks and rulers exactly cancels the
	underlying anisotropy in the speed.


Tom Roberts

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#590768 — that & this

the speed of light is only dependent upom a)
the index of refraction of the medium,
a.k.a Snell's goDDam laW.  it is only sufficient
to note that this is the application
that Liebniz made for the path of least time,
i.e of a single normal to the wavefront

> OK, let's be more careful. To me a physical theory consist of:

> In this sense, Newtonian, Lagrangian, and Hamiltonian mechanics are indeed all 
> the same theory.

> 	[#] E.g. in LET the vacuum speed of light is isotropically c
> 	only in the ether frame, but MEASUREMENTS of its speed will
> 	yield c in any inertial frame. This happens because the
> 	behavior of REAL clocks and rulers exactly cancels the
> 	underlying anisotropy in the speed.
> 
> 
> Tom Roberts

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#591112 — Re: that & this

that is to say, what he called the brachistochrone,
which is hte same as Huyghens' tautochrone, because
it takes the same amount of time, no matter,
where upon the curve it is released.  again,
this is but a single mormal to the wavefront,
which may not have been realized by those guys

> a.k.a Snell's goDDam laW.  it is only sufficient
> to note that this is the application
> that Liebniz made for the path of least time,
> i.e of a single normal to the wavefront

> > 	[#] E.g. in LET the vacuum speed of light is isotropically c
> > 	only in the ether frame, but MEASUREMENTS of its speed will
> > 	yield c in any inertial frame. This happens because the
> > 	behavior of REAL clocks and rulers exactly cancels the
> > 	underlying anisotropy in the speed.
> > 
> > 
> > Tom Roberts

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#590802

Op 25/07/2016 om 19:28 schreef Tom Roberts:
> On 7/25/16 7/25/16 - 1:45 AM, Sylvia Else wrote:
>> On 23/07/2016 1:39 PM, Tom Roberts wrote:
>>> Newtonian, Lagrangian, and Hamiltonian mechanics are all quite different
>>> theories, yet they all predict exactly the same result for any
>>> experiment within their domain (which is common to all).
>>
>> I'd tend to regard them as different manifestations of the same
>> underlying theory.
>
> OK, let's be more careful. To me a physical theory consist of:
>    1. A set of postulates (aka axioms) and theorems derived from them.
>    2. A set of definitions for the meaning of every symbol in #1.
>
> Two theories are "the same" if their #1 and #2 are both identical sets.
> Note that in #1 the distinction between postulate and theorem
> disappears, and any sufficient set of postulates will yield the same
> theory.
>
> In this sense, Newtonian, Lagrangian, and Hamiltonian mechanics are
> indeed all the same theory.
>
>
>>> Closer to this newsgroup, SR and LET are quite different theories, yet
>>> they predict the same results for any experiment within their common
>>> domain.
>>
>> They are mathematically the same. LET is just derived differently,
>> based on the
>> assumption of something that the theory doesn't include, and doesn't
>> describe.
>
> Not in the above sense. (...)

Another example is that SRT can be obtained from a set of (intuitive) 
"relativity" axioms, yielding constant speed of light as a theorem 
instead of taking in as a (non-intuitive) axiom.

-- 
guido 'wugi'

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#590939

On 7/26/16 7/26/16 - 5:11 AM, wugi wrote:
> Another example is that SRT can be obtained from a set of (intuitive)
> "relativity" axioms, yielding constant speed of light as a theorem instead of
> taking in as a (non-intuitive) axiom.

Yes. I have pointed this out many times around here. But I would characterize 
the postulate as "invariance" or "symmetry" rather than "relativity", even 
though Einstein did call it the "principle of relativity".


Tom Roberts

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