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From: Inertial on 25 Oct 2009 19:54
"Jonah Thomas" <jethomas5(a)gmail.com> wrote in message
news:20091025183936.3d80e2c5.jethomas5(a)gmail.com...
> HW@..(Henry Wilson DSc). wrote:
>> Jonah Thomas <jethomas5(a)gmail.com> wrote:
>
>> >Bear with me on this. I might be wrong, but my argument is simple and
>> >ought to be easy to understand.
>> >
>> >Until we had laser cavities that sent the same light in opposite
>> >directions, physicists who did the Sagnac experiment always started
>> >with a single light source and then used a beam-splitter etc to
>> >convert it into two separate beams of light.
>> >
>> >If a ballistic theory predicts that the speed of light depends on the
>> >speed of its source, then in every early Sagnac experiment the light
>> >went the same speed in two different directions, according to an
>> >inertial observer.

Yes. . according to one inertial observer .. the one for whom the source was
at rest at the moment of emission. The frame moving tangentially to the
source at the time of emissions. If in a diagram of sagnac we have the
source at the top at the start, and rotating clockwise, then the frame in
which the speed is c in both directions is one moving at v from left to
right

>> How did you come to that conclusion?
>
> Single light source. This source emits light at some speed, maybe c-v.

Relative to whom?

> (Note Androcles's diagram of the original Sagnac experiment, in which
> the light source faces *against* the direction of travel.)
>
> Once the single light source emits light at a single speed,

In which frame .. light (in emission theory) has an infinite number of
speeds.

> what will
> make the light change speed? Emission theories which predict that light
> changes speed regularly might give you light that arrives at the
> detector at the same time.

No .. ones that say it does NOT change speed regularly are the ones that say
no phase shift. You've got it backwards.

> But emission simple emission theories will
> predict one light speed for the Sagnac experiment, and the light will
> arrive at the detector at different times.

No .. if both beams do not have their speeds change, then they arrive
simultaneously and you get no sagnac effect

I can't believe you're still going on about this, btw,

>> >When the light is emitted it is one light beam
>> >emitted in one direction. The only way to get a change in lightspeed
>> >in that experiment comes if somehow mirrors bounce light at different
>> >speeds, or a change in direction changes the speed, etc. Simple
>> >straighforward ballistic theories would say that the light travels at
>> >the same speed relative to an inertial observer, so the light in one
>> >direction arrives sooner than the light from the other direction, and
>> >the difference in arrival time would be essentially the same as that
>> >predicted by other theories. Since this class of theories does not
>> >predict zero effect it is not refuted by Sagnac.
>>
>> Either you didn't explain this correctlyor your are plainly wrong.
>> BaTh predicts different path lengths and identical travel times. It
>> also says light cannot be regarded as a simple oscillator with
>> classical 'phase angle'. Interference is caused by different number of
>> 'wavelengths' in each path.
>
> Sure, that's your emission theory. But that isn't the only way to do an
> emission theory.

Its is NO way to do it, as is makes no sense and doesn't explain anything


From: Jonah Thomas on 25 Oct 2009 20:00
"Inertial" <relatively(a)rest.com> wrote:
> "Jonah Thomas" <jethomas5(a)gmail.com> wrote

> > When you start with one light source, that
> > light source has a speed. Period.
>
> It has an infinite number of speeds.

You start with one beam of light traveling in one direction. It has a
speed.

> > There you go, if you figure it's continually re-emitted then its
> > speed will be c plus the average speed of all the emitters.
>
> Yes .. which are in the same direction as one light beam and in the
> opposite direction to the other. And so you get two different speeds.

Yes, if you believe in the re-emission stuff. Not the only emission
theory.

> > To avoid problems for non-ballistic theories the re-emission has to
> > happen instantaneously.
>
> There is no problem in non-ballistic theories.. they predict the
> observed results

Nonballistic theories predict the observed results by ignoring the time
the light hitches a ride with the mass it gets absorbed by.
From: Inertial on 25 Oct 2009 20:12
"Jonah Thomas" <jethomas5(a)gmail.com> wrote in message
news:20091025200006.5fe742fd.jethomas5(a)gmail.com...
> "Inertial" <relatively(a)rest.com> wrote:
>> "Jonah Thomas" <jethomas5(a)gmail.com> wrote
>
>> > When you start with one light source, that
>> > light source has a speed. Period.
>>
>> It has an infinite number of speeds.
>
> You start with one beam of light traveling in one direction. It has a
> speed.

No .. it has an infinite number of speeds. A different one in each inertial
frame.

In any given inertial frame it has a single speed

>> > There you go, if you figure it's continually re-emitted then its
>> > speed will be c plus the average speed of all the emitters.
>>
>> Yes .. which are in the same direction as one light beam and in the
>> opposite direction to the other. And so you get two different speeds.
>
> Yes, if you believe in the re-emission stuff.

Or if you believe the light reflects of surfaces balistically.

The only one that doesn't give you the same speed all the time is the
weird-reflection theory where light somehow increases or decreases speed to
be the opposite difference from what it was on incident (ie if incident was
c+v, on emission it is c-v in opposite direction)

> Not the only emission
> theory.

Indeed .. but they are all refuted experimentally anyway .. so why your
obsession with them?

>> > To avoid problems for non-ballistic theories the re-emission has to
>> > happen instantaneously.
>>
>> There is no problem in non-ballistic theories.. they predict the
>> observed results
>
> Nonballistic theories predict the observed results by ignoring the time
> the light hitches a ride with the mass it gets absorbed by.

That time is minimal (if it exists). They explain the results.

Galilean Ballistic theories are refuted by experiments that show velocities
do not simply 'add' and the light from a fast moving source does not travel
faster than c.


From: Jonah Thomas on 25 Oct 2009 20:11
"Inertial" <relatively(a)rest.com> wrote:
> "Jonah Thomas" <jethomas5(a)gmail.com> wrote
> > HW@..(Henry Wilson DSc). wrote:
> >> Jonah Thomas <jethomas5(a)gmail.com> wrote:
> >
> >> >Bear with me on this. I might be wrong, but my argument is simple
> >and> >ought to be easy to understand.
> >> >
> >> >Until we had laser cavities that sent the same light in opposite
> >> >directions, physicists who did the Sagnac experiment always
> >started> >with a single light source and then used a beam-splitter
> >etc to> >convert it into two separate beams of light.
> >> >
> >> >If a ballistic theory predicts that the speed of light depends on
> >the> >speed of its source, then in every early Sagnac experiment the
> >light> >went the same speed in two different directions, according to
> >an> >inertial observer.
>
> Yes. . according to one inertial observer .. the one for whom the
> source was at rest at the moment of emission. The frame moving
> tangentially to the source at the time of emissions. If in a diagram
> of sagnac we have the source at the top at the start, and rotating
> clockwise, then the frame in which the speed is c in both directions
> is one moving at v from left to right

> >> How did you come to that conclusion?
> >
> > Single light source. This source emits light at some speed, maybe
> > c-v.
>
> Relative to whom?

The source emits light that's all the same speed. "Relative to whom" is
about what you measure that speed to be. My point is that even with an
emission theory -- any emission theory -- the light still is all the
same speed because when it is emitted it's all going the same direction.

> > (Note Androcles's diagram of the original Sagnac experiment, in
> > which the light source faces *against* the direction of travel.)
> >
> > Once the single light source emits light at a single speed,
>
> In which frame .. light (in emission theory) has an infinite number of
>
> speeds.

Pick a frame. For any frame, each bit of the light is traveling all at
the same speed, though different observers might disagree about what
speed that is. None of the observers will say "this part of the light
beam travels at one speed, and this other part of the light beam travels
at a different speed".

> > what will
> > make the light change speed? Emission theories which predict that
> > light changes speed regularly might give you light that arrives at
> > the detector at the same time.
>
> No .. ones that say it does NOT change speed regularly are the ones
> that say no phase shift. You've got it backwards.

If it does not change speed, and if -- AS IS TRUE -- it starts out all
the same speed, then the case is precisely like the non-emission
theories. Light travels at one speed in both directions and arrives at
the detector at different times.

If you want to argue that the ones which say it changes speed regularly
get a phase shift too, then you're left with a quantitative argument --
they might be wrong if they predict the wrong amount of phase shift.

> > But emission simple emission theories will
> > predict one light speed for the Sagnac experiment, and the light
> > will arrive at the detector at different times.
>
> No .. if both beams do not have their speeds change, then they arrive
> simultaneously and you get no sagnac effect

They leave the emitter all traveling at the same speed. Unless their
speeds change, then the Sagnac experiment will give the exact same
result for emission theories as for nonemission theories. It's only
emission theories that make the speeds change that are potentially
subject to test this way.
From: Jonah Thomas on 25 Oct 2009 20:21
"Inertial" <relatively(a)rest.com> wrote:
> "Jonah Thomas" <jethomas5(a)gmail.com> wrote
> > "Inertial" <relatively(a)rest.com> wrote:
> >> "Jonah Thomas" <jethomas5(a)gmail.com> wrote
> >
> >> > When you start with one light source, that
> >> > light source has a speed. Period.
> >>
> >> It has an infinite number of speeds.
> >
> > You start with one beam of light traveling in one direction. It has
> > a speed.
>
> No .. it has an infinite number of speeds. A different one in each
> inertial frame.
>
> In any given inertial frame it has a single speed

OK, like that. Given an inertial frame, all the light has the same speed
leaving the emitter.

> >> > There you go, if you figure it's continually re-emitted then its
> >> > speed will be c plus the average speed of all the emitters.
> >>
> >> Yes .. which are in the same direction as one light beam and in the
> >> opposite direction to the other. And so you get two different
> >speeds.
> >
> > Yes, if you believe in the re-emission stuff.
>
> Or if you believe the light reflects of surfaces balistically.

When the light starts out all the same speed, if you believe the light
reflects at its original speed then your emission theory is the same as
a nonemission theory for Sagnac.

> The only one that doesn't give you the same speed all the time is the
> weird-reflection theory where light somehow increases or decreases
> speed to be the opposite difference from what it was on incident (ie
> if incident was c+v, on emission it is c-v in opposite direction)

And then there's the Ritz version, but I tend to think that one has been
falsified. I could be wrong.

> > Not the only emission
> > theory.
>
> Indeed .. but they are all refuted experimentally anyway .. so why
> your obsession with them?

I'm interested. Why do you respond to me?

> >> > To avoid problems for non-ballistic theories the re-emission has
> >to> > happen instantaneously.
> >>
> >> There is no problem in non-ballistic theories.. they predict the
> >> observed results
> >
> > Nonballistic theories predict the observed results by ignoring the
> > time the light hitches a ride with the mass it gets absorbed by.
>
> That time is minimal (if it exists). They explain the results.

Why would you assume that time is minimal? If the reason light travels
at 2/3 c in fiber optic cable is that it is repeatedly absorbed and
re-emitted, it isn't unreasonable to suppose that it spends 1/3 of its
time being absorbed and re-emitted. that isn't necessarily so, but it
isn't unreasonable. Whyever would you assume that the absorption and
re-emission take minimal time? Well, because it gives you the right
answer. Scientific method -- when your predictions fail to match the
reality, add complications one at a time until they do match adequately.
Then quit.
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