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Re: Ballistic Theory and the Sagnac Experiment

Subject: Re: Ballistic Theory and the Sagnac Experiment
From: "George Dishman"
Date: Wed, 15 Mar 2006 00:02:35 -0000
Newsgroups: sci.astro, sci.physics.relativity, sci.physics
"Henri Wilson" <HW@..> wrote in message 
news:qpce12pj1grc7u7hb79bmg2f96gp4flu8q@xxxxxxxxxx
> On 14 Mar 2006 05:33:51 -0800, "George Dishman" <george@xxxxxxxxxxxxxxxxx>
> wrote:
>
>>
>>Henri Wilson wrote:
>>> On Sat, 11 Mar 2006 21:41:28 -0000, "George Dishman" 
>>> <george@xxxxxxxxxxxxxxxxx>
>>> wrote:
>>>
>
>>> >What you said is that you don't accept "the idea
>>> >of an absolute aether" but that you can apply
>>> >Maxwell's equations. Now if you have read what I
>>> >said above and thought about how you would program
>>> >it, you should understand you cannot use Maxwell's
>>> >Equations if you think light behaves ballistically.
>>>
>>> I can if I assume that Maxwells' equations produce a value for c, which 
>>> is the
>>> speed of light relative to its source.
>>
>>But they don't, Maxwell's equations produce the value
>>relative to the screen of your program. Look at how I
>>described the code and realise that the pixel calculation
>>doesn't use any information about the source, only the
>>present value of the neighbouring pixels and past value
>>of the same pixel.
>
> But according to SR, I can move my screen sideways ...

Irrelevant, the equations only permit a single speed
for all sources which is incompatibel with Ritz.

> andd the pulses will remain
> at the same original speed wrt the table.
> Silly isn't it. ..but that's what the second postulate says. No doubt 
> about it
> George.

It's also what Maxwell's Equations say Henry, no doubt
about it.

>>> >> ... is the plain fact that according to SR, all
>>> >> light in the universe traveling in any particular direction is moving 
>>> >> at
>>> >> the
>>> >> same speed.
>>> >> Note, my use of the expression 'same speed' needs no reference
>>> >> object. The value of that speed is also irrelevant.
>>> >> You can see that happening at: 
>>> >> www.users.bigpond.com/hewn/gr-aether.exe
>>> >>
>>> >> You you deny that SR makes this 'aetherian' claim?
>>> >
>>> >SR makes one claim (postulate), that the speed is
>>> >independent of the spped of the source. That comes
>>> >directly from Maxwell's Equations as you have seen
>>> >above.
>>>
>>> Which, as I have pointed out many times leads to an impossibility ...
>>
>>Which I have pointed out equally often is an untrue
>>assertion, it only conflicts with your philosophy.
>
> What is untrue about it?
>
> How can two differently moving observers at the same location get the same
> value for c via Maxwell and also measure the OWLS of a single light pulse 
> to
> also be 'c'.
> It is clearly impossible.

How can two balloons at different heights both have
the same angle of elevation for a ground observer, it
is clearly impossible - unless of course the angle is
90 degrees. In Riemann geometry that special angle
becomes the equivalent of 45 degrees or "c" as we call
it.

>>> unless one
>>> assumes absolute space.
>>> (even if two differently moving observers get the same values for the
>>> constants, it is obvious that a pulse of light cannot travel at the same 
>>> speed
>>> wrt both)
>>>
>>> >>>> The explanation might be difficult to find but it
>>> >>>> has to exist. I have offered several suggestions already that might
>>> >>>> provide a
>>> >>>> clue.
>>> >>>
>>> >>>All of which are incompatible with Maxwell's Equations
>>> >>>since they require speeds other than c. That was my point.
>>> >>
>>> >> Maxwell's equations require a reference for speed.
>>> >
>>> >Look at the equations, they tell you what it is.
>>> >
>>> >> It WAS and still IS, an absolute aether.
>>> >
>>> >Wrong, if aether is moving wrt the x,t coordinates
>>> >used in the equations then a wave moving at c wrt
>>> >the aether is not a valid solution of the equations.
>>> >I know the philosophical views held at the time but
>>> >the equations do not permit it.
>>>
>>> That's a strange way to express what you are trying to prove.
>>> The Aether doesn't MOVE. Things move wrt IT.
>>
>>I see you have forgotten even Galilean relativity :-)
>
> No George,

Yes Henry, "The Aether doesn't MOVE. Things move wrt IT."
ignores Galilean relativity.

> I often refer to the aether concept to demonstrate that SR is
> identical to it.

I know, you make a lot of mistakes that way.

>>> >>>They don't need to be, it is fundamental to the
>>> >>>equations that they are constants so can be measured
>>> >>>in the lab at varying densities and extrapolated to
>>> >>>a vacuum.
>>> >>
>>> >> All Maxwell produces is a value of the universal constant 'c' anyway.
>>> >
>>> >Right, and all propagating waves must travel at
>>> >that speed if they are to be valid solutions.
>>>
>>> Only in a medium.
>>
>>Nope, Maxwell's Equations still give the same result
>>if you apply them to a perfect vacuum.
>
> But 'Light speed' in a perfect vacuum has no physical meaning. What is the
> reference for that speed?

They are just equations Henry, they give the same
result if you apply them to a perfect vacuum whether
we can assign that physical meaning or not.

> A perfect vacuum contains an infinite number of
> differently moving imaginary points. To which one does Maxwell's 'c' 
> refer?

All of them, that's the point.

> The whole theory is ridiculous without a light carrying medium.

There is no medium in the equations no matter
how ridiculous you might think that is.

>>> Otherwise light moves at c wrt its source. What other speed referece 
>>> does it
>>> have?
>>
>>Rhetorical questions don't alter the equations, and
>>they only allow one speed for their solution. Perhaps
>>you should get out a maths text book that covers
>>solving differential equations.
>
> No George.

That doesn't surprise me.

> Maxwell's equations allow for an infinite number of speeds in a
> perfect vacuum. One speed for every differently moving imaginary point.

The same speed.

>>> >> George, if two differently moving observers measure the constants at 
>>> >> the
>>> >> same
>>> >> point (as they pass each other) do they both come up with the same 
>>> >> value
>>> >> for
>>> >> 'c'?
>>> >
>>> >They wouldn't be "universal constants" if they didn't.
>>> >
>>> >> If you consider a single pulse of light approaching the two, what 
>>> >> does
>>> >> that
>>> >> imply? According to you, both calculate its speed to be c.
>>> >
>>> >That is the only valid solution to the equations, yes.
>>> >
>>> >> <-O1----------------<-p-----------
>>> >> ->O2
>>> >>
>>> >> Your claim is clearly impossible ...
>>> >
>>> >It's not a claim Henry, basic calculus proves it.
>>> >
>>> >http://www.phys.unsw.edu.au/einsteinlight/jw/module3_Maxwell.htm#light
>>> >
>>> >> ... unless the LTs apply and 'v' is absolute.
>>> >
>>> >You can derive the transforms from them. That is exactly
>>> >what Einstein did.
>>>
>>> You are using circular logic again. You are assuming the second 
>>> postulate to
>>> derive transforms that in turn support the second postulate.
>>> This is surely a joke George.
>>
>>What are you gibbering about Henry? Maxwell didn't
>>use Einstein's postulate to develop his Equations, you
>>know that perfectly well.
>
> Correct.

In which case it isn't circular.

> He used an absolute medium.

No he didn't, he derived them from existing
empirical formulae which were derived from
lab experiments with Leyden jars and coils.

>>> >> ....and as I have explained above, that is clearly impossible
>>> >
>>> >I note your words but you have given no explanation,
>>> >just a repeated assertion. On the other hand the page
>>> >I cited is one of many that derives the speed using
>>> >maths that only allows one solution.
>>>
>>> It gives one solution for the constant 'c' but it give no reference for 
>>> speed.
>>
>>I suggest you read the page again, or don't you
>>know how to solve differential equations?
>
> One doesn't have to solve them to understand what they mean physically.

Yes you do. Go learn some maths.

> If I
> wanted to solve them I would look it up in a book somewhere.

Please do so.

> That doesn't alter the fact that speed can only be specified relative to
> something. Maxwell's 'c' is merely a constant.
>
>>> There is only one solution. Light initially moves at c wrt its source.
>>
>>Nope, it has the same value of dx/dt for all sources
>>regardless of the motion of the source. Read the page.
>
> Which is nonsense of course

That's your opinion, but that's the ONLY solution
allowed by the equations.

> ... UNLESS AN AETHER EXISTS in which case every
> differently moving observer would really be measuring a different relative
> light speed but wouldn't be aware of the fact.
>
>>> What
>>> other factors are you claiming for the determination of light speed wrt 
>>> its
>>> source, George?
>>
>>I'm not claiming any factors at all, just pointing out
>>that Maxwell's Equations only allow one speed
>>for all sources. It's simple maths Henry, you don't
>>even need to consider the physics.
>
> You are repeating the same meaningless drivel over and over.

I am telling you basic calculus which you
should know already.

> Either you accept that you are stating 'light speed moves at c wrt its 
> source'
> or you must accept an absolute aether.

That is what you would like, it is not what the
equations tell you. They say it is c relative
to the inertial reference frame which defines
x and t. In terms you might find easier, they
say the speed is c relative to the observer.
If you try to use the equation for light moving
at c relative to the source or relative to any
arbitrary aether, you will find you CANNOT solve
them. Basic maths Henry.

>>> >> in the case of
>>> >> two differently moving observers. A single light pulse cannot 
>>> >> approach
>>> >> both at
>>> >> 'c'.
>>> >> Can you not see the error you are making?
>>> >
>>> >I can see you are ignoring basic calculus. If you don't
>>> >want to have a single speed for light from differently
>>> >moving sources then you cannot use Maxwell's Equations.
>>> >the choice is yours Henry, you cannot have it both ways.
>>>
>>> I cannot use maxwell's method without an aether unless I accept that it 
>>> merely
>>> provides a value for the constant c, which is also the speed of light 
>>> wrt its
>>> source.
>>
>>You don't have any choice in the matter, the equations
>>are completely explicit.
>
> The equations give a value for speed relative to an absolute frame.

Wrong, go read that maths book.

> In a perfect vacuum, there is no such frame. Maxwell's c therefore 
> produces an
> infinite number of 'speeds'.
>
>
>>> >I understand, the critical distance is da/c^2 as
>>> >we discussed some time ago and it's just the ratio
>>> >of the actual distance to that value that matters,
>>> >however when I changed distance from 0.001 light
>>> >years to 3000 light years, the light curve was
>>> >unaffected. That can't be right! I'm sure it's a
>>> >simple bug or maybe there's an "update" button I
>>> >need to press and didn't notice.
>>>
>>> It works pefectly well for me.
>>
>>Well previously you had a button I missed or maybe
>>the program got into a state where it didn't update
>>the display, just tell me what settings to use.
>
> Just run it with the default settings. Then change the distance to say 
> 0.5.

OK, I'll try again tomorrow.

>>> If your distances are well beyond eth critical
>>> one, you wont see much difference ...but the light curve is pretty 
>>> meaningles
>>> there anyway because it if a sufficient number of orbits were included 
>>> it would
>>> be flat.
>>
>>That's right, but it never went flat, it retained the
>>same curve as when close to the critical distance.
>
> The curves are only of value before the critical distance is reached.
> After that too many multiple images appear (if extinction is not 
> considered).

That's the point, we never see multiple images
so extinction must be included, and that will
significantly change your results.

>>> >>>Try modelling the pulsar and see if you can
>>> >>>get sensible results, if so tell me what
>>> >>>numbers to enter into the screens.
>>> >>
>>> >> I will need its distance and frequency.....also its brightness curve
>>> >> shape.
>>> >> Pulsars are not good subjects for my program.
>>> >
>>> >Distance is 3617 light years, orbital period
>>> >1.5 days, circular orbit of diameter 3.8 light
>>> >seconds using conventional analysis. Using Ritz
>>> >the diameter is undefined though probably not
>>> >to significant for the reasons I gave a few days
>>> >ago, but the key element will be the inclination.
>>>
>>> Apparently the orbit is edge on.
>>>
>>> ..but this is a clear case of trying to establish reality for a 
>>> willusion.
>>
>>I think even with ballistic theory, the dip would
>>suggest near grazing, but that's the point, you
>>have complete freedom to determine an
>>alternative orbit from the data using your
>>program.
>>
>>> We simply cannot believe any of these readings.
>>
>>Of course we can trust the readings, they aren't
>>in question, it is the _interpretation_ of the readings
>>that you need to revise using ballistic theory. If you
>>can't, ballistic theory is falsified by observation again.
>
> You wish, George.
> Observing distant stars is a lot more complicated that looking at 
> something
> across the road, where light speed doesn't matter.

You time the arrival of the pulses against a local
clock. It is far from easy of course, but your ideas
on the source speed don't invalidate the measurement
process, they only influence how the orbit would be
inferred from the times.

George



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