Re: Aether or whatever

On 19 Feb, 10:45, "sean" <jaymose...@xxxxxxxxxxx> wrote:
On 18 Feb, 18:05, "George Dishman" <geo...@xxxxxxxxxxxxxxxxx> wrote:
"Jeff Root" <j...@xxxxxxxxxxxx> wrote in message
news:1171653190.616919.224670@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

George,

You and Sean are obviously talking about two different
things here. Sean is right that the light travels in a
straight line, and you are right that it travels in a curve.

I haven't seen any of the simulation animations in several
weeks, and I don't know whether I've seen the specific one
you're talking about here. Maybe the speed of the light
beam shown in the sim is slow enough that the curvature
would be visible. If the light traverses the entire field of
view within a single frame of the animation (not coordinate
frame!), then the path may appear to be straight. If the
light takes more than one animation frame to traverse the
field of view, then it should visibly curve.

Ive appended my response to Georges other post here at the end . But
yes, Jeffs point is valid . It was not clear to me what moved , what
didnt move and why,.. in georges inertial lab frame sim. Although now
I think Ive worked out what george means. His inertial lab frame has
light at c in a straight line and that line DOESNT move in the sim
whereas the lab does (although it wasnt made clear by george nor was
it made clear in the sim what moved and what didnt. Hence the
misunderstanding)

It was made clear Sean, I explained repeatedly
what "inertial" meant and toold you several times
that the frame was inertial but whatever the reason
for the disconnect, that has been cleared up and
there remains a clear difference between our views
on how light propagates.

This is my animation which was intended to clarify
the names I was using for the three frames:

http://www.georgedishman.f2s.com/Sean/SagFrame3.html

The photon motion is slowed to make the paths clearer.
In fact it has highlighted that we have quite different
views of how light moves.

Sean is arguing that my diagrams are wrong and that
in fact the light should move in a straight line in
the lower left panel, the "Non-rotating source frame".

Read the comment for Sean's "sagnac 5":

http://www.youtube.com/watch?v=jyYCapBDIJA

"This is what SR predicts in the source frame by
transposing whats predicted in the lab frame to the
source frame. This shows how SR isnt consistent in
more than one frame. As you can see if the photon
leaves the source in a straight line at c in the lab
frame it is a curved path at variable speeds in the
source frame. Emmission theory on the other hand is
consistent in all frames."

On the other hand, here is his "sagnac 4":

http://www.youtube.com/watch?v=GW-6BHldn_Q

"Here its a source frame simulation showing the lab
rotating around the source. The illusion is that the
photon (moving red dot) has a variable path and
speed relative to the source(static red dot) and lab.
In fact one can see that the red dot photon still
travels at a constant speed and path relative to the
source."

Of course his argument is fallacious since the latter
is no more consistent. I could equally write:

Once again George fails to understand and I hope Jeff realizes this.
Sagnac 5 shows what SR would predict whereas sagnac 4 shows what
emmission theory predicts. That George should pretend that I intended
sagnac 5 to represent emmission theory is complete nonsense.

Sean, what are you talking about? I quoted your
entire comment field above so it made it
completely clear you were talking about SR.

Just go
to the site , look at the acompanying text and it says clearly..."
Sagnac 5 is what SR wrongly predicts.." Of course its not consistent
with sagnac 4. Sagnac 4 shows what emmision theory predicts. They are
simulations of two completely different theories.

Of course they are, that's why I quoted your
comments !!!

I'll snip some history from the other posts
just to get the size down:

I expect you do. You got the path wrong in the sim
but that was because you assumed it was straight in
the source frame rather than a problem in transforming.

It has to be straight in the source frame (and at c)
in the model of emmission theory.

That isn't possible, the light from the torch
heading for Sirius still gets there if you move
the torch after the light has left.

What prevents it from getting there? The torch moved maybe 10 inches

The light moves from side to side by 2 AU during the
8.6 year journey to Sirius! You are forgetting the
Earth orbits the Sun. What do you think causes the
light to move that way? Would it still do that if
a rogue planet knowcked the Earth out of its orbit
or would the light start moving sideways to remain
directly between Earth and Sirius?

... And if you rotate the torch , as I said earlier that
doesnt drag the beam.

Exactly. Now I agree with that, but I also say
that if you slide the torch from side to side
it doesn't drag the light either. You want
rotation not to have an effect but sideways
motion to drag the light.

Anyways I think one has to look at it from the
torches point of view. It HASNT moved.

It is on the Earth which goes round the Sun
once a year, unless you are saying Ptolemy
was right and Copernicus was wrong. The Earth
orbits the Sun because it is pulled by the
gravity of the Sun. What is poulling the light
to keep it lined up with the source?

Dont forget its the source and
its always at rest. The rest of the universe moves relative to the
source.

In that view, why doesn't whatever causes the
rest of the universe to move also move the light?

....
Ritzs couldnt explain both MMx and sagnac whereas mine does. And
seeing as youve no proof to show that light doesnt propagate in
straight lines at c relative to the source ...

Try drawing a single diagram showing the light from
two torches, one on Earth and one on Mars, both going
to Sirius at the same time as seen by someone at rest
relative to the rest of the galaxy.

George

.

Relevant Pages

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