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Fermat

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  Fermat RichD <r_delaney2001@yahoo.com> - 2018-07-03 09:52 -0700
    Re: Fermat Tom Roberts <tjroberts137@sbcglobal.net> - 2018-07-03 13:50 -0500
      Re: Fermat Oren Woodcock <uw@osiweoq.lp> - 2018-07-04 10:13 +0000
      Re: Fermat Koobee Wublee <koobee.wublee@gmail.com> - 2018-07-04 11:58 -0700
        Re: Fermat Tom Roberts <tjroberts137@sbcglobal.net> - 2018-07-04 15:08 -0500
          Re: Fermat Koobee Wublee <koobee.wublee@gmail.com> - 2018-07-04 22:23 -0700
      Re: Fermat alsor@interia.pl - 2018-07-04 12:54 -0700
        Re: Fermat Tom Roberts <tjroberts137@sbcglobal.net> - 2018-07-04 17:12 -0500
          Re: Fermat Koobee Wublee <koobee.wublee@gmail.com> - 2018-07-04 22:25 -0700
          Re: Fermat JanPB <filmart@gmail.com> - 2018-07-05 09:45 -0700
            Re: Fermat Tom Roberts <tjroberts137@sbcglobal.net> - 2018-07-05 12:05 -0500
            Re: Fermat Koobee Wublee <koobee.wublee@gmail.com> - 2018-07-05 10:40 -0700
          Re: Fermat alsor@interia.pl - 2018-08-11 11:42 -0700
      Re: Fermat RichD <r_delaney2001@yahoo.com> - 2018-07-05 09:19 -0700
        Re: Fermat Tom Roberts <tjroberts137@sbcglobal.net> - 2018-07-05 13:09 -0500
          Re: Fermat Koobee Wublee <koobee.wublee@gmail.com> - 2018-07-05 12:08 -0700
            Re: Fermat JanPB <filmart@gmail.com> - 2018-08-11 16:55 -0700
              Re: Fermat Owen Scharff <nehh@fenvhw.ho> - 2018-08-12 11:21 +0000
                Re: Fermat JanPB <filmart@gmail.com> - 2018-08-13 12:29 -0700
                  Re: Fermat Lovu Biftek <ufeli@fupuks.cl> - 2018-08-13 21:35 +0000
                    Re: Fermat JanPB <filmart@gmail.com> - 2018-08-13 14:44 -0700
              Re: Fermat Koobee Wublee <koobee.wublee@gmail.com> - 2018-08-12 11:36 -0700
                Re: Fermat JanPB <filmart@gmail.com> - 2018-08-13 12:31 -0700
                  Re: Fermat Koobee Wublee <koobee.wublee@gmail.com> - 2018-08-13 16:26 -0700
              Re: Fermat alsor@interia.pl - 2018-08-13 09:08 -0700
                Re: Fermat JanPB <filmart@gmail.com> - 2018-08-13 12:33 -0700
                  Re: Fermat Koobee Wublee <koobee.wublee@gmail.com> - 2018-08-13 16:36 -0700
                    Re: Fermat JanPB <filmart@gmail.com> - 2018-08-13 19:18 -0700
                      Re: Fermat Koobee Wublee <koobee.wublee@gmail.com> - 2018-08-13 22:11 -0700
                      Re: Fermat Lovu Biftek <ufeli@fupuks.cl> - 2018-08-16 19:15 +0000
                  Re: Fermat alsor@interia.pl - 2018-08-14 12:36 -0700
                    Re: Fermat JanPB <filmart@gmail.com> - 2018-08-14 13:21 -0700
                      Re: Fermat Lovu Biftek <ufeli@fupuks.cl> - 2018-08-14 20:26 +0000
                        Re: Fermat alsor@interia.pl - 2018-08-16 09:29 -0700
                      Re: Fermat alsor@interia.pl - 2018-08-16 09:25 -0700
                        Re: Fermat Tom Roberts <tjroberts137@sbcglobal.net> - 2018-08-16 12:19 -0500
                          Re: Fermat alsor@interia.pl - 2018-08-16 10:44 -0700

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#463353 — Fermat

What happens to Fermat's principle of least time, in conditions 
of strong gravity, curved space?


--
Rich

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#463359

On 7/3/18 11:52 AM, RichD wrote:
> What happens to Fermat's principle of least time, in conditions
> of strong gravity, curved space?

Nothing. Though in GR it is curved spaceTIME [@]: Spacelike geodesics are still 
paths of extremal (usually minimum) distance, and timelike geodesics are still 
paths of extremal (usually maximum) proper time. Small objects [#] still follow 
timelike geodesics. But large objects do not, for the simple reason that they 
affect the geometry of spacetime.

	[@] Speaking loosely, it is curvature involving the time
	direction that generates "acceleration due to gravity".

	[#] "Small" in the sense that their effect on geometry can
	be neglected.

Tom Roberts

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#463408

Tom Roberts wrote:

> On 7/3/18 11:52 AM, RichD wrote:
>> What happens to Fermat's principle of least time, in conditions of
>> strong gravity, curved space?
> 
> Nothing. Though in GR it is curved spaceTIME [@]: Spacelike geodesics
> are still paths of extremal (usually minimum) distance, and timelike
> geodesics are still paths of extremal (usually maximum) proper time.
> Small objects [#] still follow timelike geodesics. But large objects do
> not, for the simple reason that they affect the geometry of spacetime.

Once again, fully consistent with my

_Divergent Matter of the Moving Bodies Model_. Mister Einstine went 
farther than Newton, providing a MECHANISM for the fictitious "force of 
gravity", but NOT far enough as I do. He didn't complete the square, so to 
speak.

> [@] Speaking loosely, it is curvature involving the time direction 
> that generates "acceleration due to gravity".

Time has no direction in 3d space. On an axis, it always has one, but 
that's fictitious correspondingly.

> [#] "Small" in the sense that their effect on geometry can be
> neglected. Tom Roberts

Disregard size, that "geometry" will still be ONE geometry super-
positioned, not two nor many. You are doing a little mistake I suppose.

But geometry alone is not providing the required MECHANISM. The fictitious 
"curvature" of the empty spacetime can't possibly have any internal 
structure. Hence, no mechanism is added to the Model.

Excellent post, thank you.

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#463432

On Tuesday, July 3, 2018 at 11:50:42 AM UTC-7, tjrob137 wrote:
> On 7/3/18 11:52 AM, RichD wrote:

> > What happens to Fermat's principle of least time, in conditions
> > of strong gravity, curved space?
> 
> Nothing. Though in GR it is curved spaceTIME:

The foundation of all geodesic paths follow the shortest distance in spacetime is fatally flawed.  As light always propagates with a null spacetime path, this model does not allow a coherent path of light propagation.  <shrug>

Also, has anyone ever looked into this model in 3-d space?  The Lagrangian result makes no sure.  Thus, the model cannot be a valid law of physics that is an event taking place in spacetime cannot follow the shortest path in space or in spacetime.  It must be wrong, but that does not prevent these buffoons to create the religion of GR.  <shrug>

Thus, in conclusion, Fermat’s principle must rule as the universal law of physics where there is still an undiscovered mechanism governing the evolution of an event taking place in space and time.  <shrug>

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#463434

On 7/4/18 1:58 PM, Koobee Wublee wrote:
> On Tuesday, July 3, 2018 at 11:50:42 AM UTC-7, tjrob137 wrote:
>> in GR it is curved spaceTIME:
> 
> The foundation of all geodesic paths follow the shortest distance in
> spacetime is fatally flawed. 

Hmmmm. It is Koobee Wublee's MISUNDERSTANDING of GR that is fatally 
flawed, because it is simply not true that in a Lorentzian manifold all 
geodesics "follow the shortest distance in spacetime".

> As light always propagates with a null
> spacetime path, this model does not allow a coherent path of light
> propagation. 

You are confused, and ignorant of how GR _ACTUALLY_ handles null 
geodesics. You seem to be confusing null geodesics with timelike 
geodesics (for which proper time can be used as the affine parameter of 
the trajectory). For a null geodesic, there is no proper time, but one 
can choose any appropriate affine parameter of the trajectory, and 
derive the usual geodesic equation using it.

	For instance, if one has the coordinates of a locally-
	inertial frame, then any coordinate {x,y,z,t} can be
	used as the affine parameter of a geodesic within
	the domain of the frame, as long as the geodesic is
	not orthogonal to that axis. This applies to all
	geodesics, timelike, spacelike, or null.
	Hint: relative to a locally-inertial frame, all
	geodesics are straight lines.
	Hint: this also applies to Euclidean manifolds
	(inertial frame => Cartesian coordinates).

Equivalently, the geodesic is defined by parallel-propagating its 
tangent 4-vector. Had KW understood this, he would not have confused 
himself with the spacetime interval along a null geodesic always being zero.

> Also, has anyone ever looked into this model in 3-d space? [...]

Useless. Relativity inherently uses a 4-d Lorentzian space-time 
manifold. In the world being modeled, time is important to physics.

> [... further nonsense ignored.]

Tom Roberts

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#463466

On Wednesday, July 4, 2018 at 1:08:11 PM UTC-7, tjrob137 wrote:
> On 7/4/18 1:58 PM, Koobee Wublee wrote:

> > The foundation of all geodesic paths follow the shortest distance in
> > spacetime is fatally flawed. 
> 
> it is simply not true that in a Lorentzian manifold all geodesics
> "follow the shortest distance in spacetime".

The mathematics of GR does not agree with what Tom says.  <shrug>

> > As light always propagates with a null spacetime path, this model
> > does not allow a coherent path of light propagation. 
>
> You are ignorant of how GR _ACTUALLY_ handles null geodesics. You seem
> to be confusing null geodesics with timelike geodesics (for which
> proper time can be used as the affine parameter of the trajectory).

What you refer to as timelike and lightlike are covered in the same mathematics of GR.

> For a null geodesic, there is no proper time,

Tom is making shit up as usual.  There is no such mythical quantity called proper time.  Each frame of reference exists its own local clock tick rate.  <shrug>

> one can choose any appropriate affine parameter of the trajectory, and 
> derive the usual geodesic equation using it.

So, why doesn’t Tom show up how the mathematics of light and others are different.  <shrug>

> [rest of nonsense as read from the scripture of GR snipped]

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#463433

W dniu wtorek, 3 lipca 2018 20:50:42 UTC+2 użytkownik tjrob137 napisał:
> On 7/3/18 11:52 AM, RichD wrote:
> > What happens to Fermat's principle of least time, in conditions
> > of strong gravity, curved space?
> 
> Nothing. Though in GR it is curved spaceTIME [@]: Spacelike geodesics are still 
> paths of extremal (usually minimum) distance, and timelike geodesics are still 
> paths of extremal (usually maximum) proper time. Small objects [#] still follow 
> timelike geodesics. But large objects do not, for the simple reason that they 
> affect the geometry of spacetime.
> 
> 	[@] Speaking loosely, it is curvature involving the time
> 	direction that generates "acceleration due to gravity".
> 
> 	[#] "Small" in the sense that their effect on geometry can
> 	be neglected.
> 
> Tom Roberts


In the GR the Fermat principle doesn't exist at all.

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#463447

On 7/4/18 2:54 PM, alsor@interia.pl wrote:
> In the GR the Fermat principle doesn't exist at all.

Sure it does, as long as one remembers to apply it in a locally inertial 
frame, at each point along the null geodesic the light is following. If 
there are optical media involved, Fermat's principle holds in the 
geometrical-optics approximation.

Tom Roberts

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#463467

On Wednesday, July 4, 2018 at 3:13:02 PM UTC-7, tjrob137 wrote:
> On 7/4/18 2:54 PM, alsor@interia.pl wrote:

> > In the GR the Fermat principle doesn't exist at all.
> 
> Sure it does,

No, GR does not allow for Fermat’s principle.  The buffoons that support GR dropped this ball.  <shrug>

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#463510

On Wednesday, July 4, 2018 at 3:13:02 PM UTC-7, tjrob137 wrote:
> On 7/4/18 2:54 PM, alsor@interia.pl wrote:
> > In the GR the Fermat principle doesn't exist at all.
> 
> Sure it does, as long as one remembers to apply it in a locally inertial 
> frame, at each point along the null geodesic the light is following. If 
> there are optical media involved, Fermat's principle holds in the 
> geometrical-optics approximation.
> 
> Tom Roberts

I think Koobee is confused between 4D and 3D (he is trying to apply Fermat to the
former which yields nothing, of course, and then proceeds to declaring victory :-) ).

--
Jan

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#463513

On 7/5/18 11:45 AM, JanPB wrote:
> On Wednesday, July 4, 2018 at 3:13:02 PM UTC-7, tjrob137 wrote:
>> On 7/4/18 2:54 PM, alsor@interia.pl wrote:
>>> In the GR the Fermat principle doesn't exist at all.
>>
>> Sure it does, as long as one remembers to apply it in a locally inertial
>> frame, at each point along the null geodesic the light is following. If
>> there are optical media involved, Fermat's principle holds in the
>> geometrical-optics approximation.
>>
>> Tom Roberts
> 
> I think Koobee is confused between 4D and 3D (he is trying to apply Fermat to the
> former which yields nothing, of course, and then proceeds to declaring victory :-) ).

Koobee is MUCH more confused than that -- just look at what he writes.

Tom Roberts

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#463527

On Thursday, July 5, 2018 at 9:45:33 AM UTC-7, JanPB wrote:
> Koobee Wublee wrote:

> > The foundation of all geodesic paths follow the shortest distance
> > in spacetime is fatally flawed.  As light always propagates with
> > a null spacetime path, this model does not allow a coherent path
> > of light propagation.  <shrug>
>
> > Also, has anyone ever looked into this model in 3-d space?  The
> > Lagrangian result makes no sure.  Thus, the model cannot be a
> > valid law of physics that is an event taking place in spacetime
> > cannot follow the shortest path in space or in spacetime.  It must
> > be wrong, but that does not prevent these buffoons to create the
> > religion of GR.  <shrug>
>
> > Thus, in conclusion, Fermat’s principle must rule as the universal
> > law of physics where there is still an undiscovered mechanism
> > governing the evolution of an event taking place in space and time.
> > <shrug>
> 
> I think Koobee is confused between 4D and 3D (he is trying to apply
> Fermat to the former which yields nothing, of course, and then
> proceeds to declaring victory :-) ).

Idiot!  There is nothing what Koobee Wublee wrote that would collaborate with your claim.  It is Tom that thinks Fermat’s principle has anything to do with GR which it does not.  <shrug>

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#467595

W dniu czwartek, 5 lipca 2018 00:13:02 UTC+2 użytkownik tjrob137 napisał:

> > In the GR the Fermat principle doesn't exist at all.
> 
> Sure it does, as long as one remembers to apply it in a locally inertial 
> frame, at each point along the null geodesic the light is following. If 
> there are optical media involved, Fermat's principle holds in the 
> geometrical-optics approximation.
> 
> Tom Roberts

In GR the Fermat principle has been replaced
by a fictitious number minimalization: the artificial Lorentz's time.

Thus the results provided by GR are wrong.

For example:
the light time of transmission delays (Shapiro)
in the GR are permanently 20us overestimated than the measured times.

4GM_sun/c^2 = 2r_s/c = 0.00002s = 20us.

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#463505

On July 3, tjrob137 wrote:
>> What happens to Fermat's principle of least time, in conditions
>> of strong gravity, curved space?
> 
> Nothing. Though in GR it is curved spaceTIME [@]: Spacelike 
> geodesics are still paths of extremal (usually minimum) distance, 
> and timelike geodesics are still paths of extremal (usually maximum) 
> proper time.  

Fermat's principle is not a fundamental law, but a 
corollary of EM.  As a theorem, its validity follows 
from its premises.  What are the conditions on which 
it depends?  I'd guess there are pathological cases 
where it fails, and wonder if strong gravity is one such.


--
Rich

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#463529

On 7/5/18 11:19 AM, RichD wrote:
> On July 3, tjrob137 wrote:
>>> What happens to Fermat's principle of least time, in conditions
>>> of strong gravity, curved space?
>>
>> Nothing. [...]
> 
> Fermat's principle is not a fundamental law, but a
> corollary of EM.  As a theorem, its validity follows
> from its premises.  What are the conditions on which
> it depends?  I'd guess there are pathological cases
> where it fails, and wonder if strong gravity is one such.

In GR, light rays [#] follow null geodesic paths in vacuum. From this it 
immediately follows that Fermat's principle applies to them in any 
locally-inertial frame along the light path. In GR this applies in regions of 
strong gravity, as long as the light ray itself is "small" enough to not 
significantly affect the geometry.

In the geometrical optics approximation, Fermat's principle in a locally 
inertial frame holds even when optical media are involved. I'm pretty sure this 
holds in a region of strong gravity; much care is needed if various portions of 
the optical medium do not remain at rest with respect to each other....

     [#] "Small" ones, that do not significantly affect the geometry.

Tom Roberts

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#463540

On Thursday, July 5, 2018 at 11:09:43 AM UTC-7, tjrob137 wrote:

> In GR, light rays follow null geodesic paths in vacuum.

Yes, the spacetime trajectory for light is null, but the mathematics of GR cannot propagate in a coherent path.  When we dropped a ball at height, the path of straight down follows the shortest distance in spacetime.  When light propagates from point A to B, null spacetime occurs in any path you can imagine so.  GR is fatally flawed.  <shrug>

> From this it immediately follows that Fermat's principle applies to
> them in any locally-inertial frame along the light path.

Bullshitting again, Tom.  <shrug>

> [rest of make-up nonsense snipped]

Please try to refrain from creating your own laws of physics for a change.  <shrug>

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#467606

On Thursday, July 5, 2018 at 12:08:03 PM UTC-7, Koobee Wublee wrote:
> On Thursday, July 5, 2018 at 11:09:43 AM UTC-7, tjrob137 wrote:
> 
> > In GR, light rays follow null geodesic paths in vacuum.
> 
> Yes, the spacetime trajectory for light is null, but the mathematics of GR cannot propagate in a coherent path.  When we dropped a ball at height, the path of straight down follows the shortest distance in spacetime.  When light propagates from point A to B, null spacetime occurs in any path you can imagine so.  GR is fatally flawed.  <shrug>

It's not "fatally flawed", it's simply that all light paths would have length zero when
considered as paths in spacetime, so the principle does not apply in that context.
It's a bit like asking what's the shortest path from the north to the south pole: ALL
meridional paths are of equal length, and this doesn't mean that "geodesy and
airplane navigation is fatally flawed".

What have you been smoking.

--
Jan

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#467624

JanPB wrote:

> On Thursday, July 5, 2018 at 12:08:03 PM UTC-7, Koobee Wublee wrote:
>> On Thursday, July 5, 2018 at 11:09:43 AM UTC-7, tjrob137 wrote:
>> 
>> > In GR, light rays follow null geodesic paths in vacuum.
>> 
>> Yes, the spacetime trajectory for light is null, but the mathematics of
>> GR cannot propagate in a coherent path.  When we dropped a ball at
>> height, the path of straight down follows the shortest distance in
>> spacetime.  When light propagates from point A to B, null spacetime
>> occurs in any path you can imagine so.  GR is fatally flawed.  <shrug>
> 
> It's not "fatally flawed", it's simply that all light paths would have
> length zero when considered as paths in spacetime, so the principle does
> not apply in that context. It's a bit like asking what's the shortest
> path from the north to the south pole: ALL meridional paths are of equal
> length, and this doesn't mean that "geodesy and airplane navigation is
> fatally flawed". What have you been smoking.

You fell into the trap with both legs. The photon feels no time and 
distance. Your analogy is something without o, g and y.

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#467752

On Sunday, August 12, 2018 at 4:21:35 AM UTC-7, Owen Scharff wrote:
> JanPB wrote:
> 
> > On Thursday, July 5, 2018 at 12:08:03 PM UTC-7, Koobee Wublee wrote:
> >> On Thursday, July 5, 2018 at 11:09:43 AM UTC-7, tjrob137 wrote:
> >> 
> >> > In GR, light rays follow null geodesic paths in vacuum.
> >> 
> >> Yes, the spacetime trajectory for light is null, but the mathematics of
> >> GR cannot propagate in a coherent path.  When we dropped a ball at
> >> height, the path of straight down follows the shortest distance in
> >> spacetime.  When light propagates from point A to B, null spacetime
> >> occurs in any path you can imagine so.  GR is fatally flawed.  <shrug>
> > 
> > It's not "fatally flawed", it's simply that all light paths would have
> > length zero when considered as paths in spacetime, so the principle does
> > not apply in that context. It's a bit like asking what's the shortest
> > path from the north to the south pole: ALL meridional paths are of equal
> > length, and this doesn't mean that "geodesy and airplane navigation is
> > fatally flawed". What have you been smoking.
> 
> You fell into the trap with both legs. The photon feels no time and 
> distance. Your analogy is something without o, g and y.

Reread what I wrote.

--
Jan

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#467769

JanPB wrote:

>> > It's not "fatally flawed", it's simply that all light paths would
>> > have length zero when considered as paths in spacetime, so the
>> > principle does not apply in that context. It's a bit like asking
>> > what's the shortest path from the north to the south pole: ALL
>> > meridional paths are of equal length, and this doesn't mean that
>> > "geodesy and airplane navigation is fatally flawed". What have you
>> > been smoking.
>> 
>> You fell into the trap with both legs. The photon feels no time and
>> distance. Your analogy is something without o, g and y.
> 
> Reread what I wrote.

If you are that smart, tell me how to get a job at the large hadron 
colider. You've been there and know what is going on.

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