Re: Missing replies Draper requested.

From: PD (pdraper_at_yahoo.com)
Date: 01/27/05 

Date: 27 Jan 2005 13:37:15 -0800

[snip headers to keep within Google length limit]

> : >>>>>>>> Consider the Advanced Light Source, a LBL laboratory
devoted
> : >> to
> : >>>>>>>> research using synchrotron radiation.
> : >>>>>>>> http://www-als.lbl.gov/als/als_users_bl/bl_layout.html
> : >>>>>>>>
> : >>>>>>>> *Because the source of the radiation is a train of
electron
> : >>>> bunches
> : >>>>>>>> traveling nearly at c, and
> : >>>>>>>> *Because the experiments trigger their experiments based
on a
> : >>>> time
> : >>>>>> of
> : >>>>>>>> flight from the electron bunch that can certainly
distinguish
> : >>>>>> between
> : >>>>>>>> a
> : >>>>>>>> light speed of c and a light speed of ~2c, and
> : >>>>>>>> *Because the beams are distributed nearly completely
around
> : >> the
> : >>>>>>>> azimuth
> : >>>>>>>> of the ring, thereby being sensitive to any speed of the
> : >> "river"
> : >>>>>> that
> : >>>>>>>> the ring is immersed in, then
> : >>>>>>>>
> : >>>>>>>> one can conclude that light's speed is dependent neither
on
> : >> the
> : >>>>>> speed
> : >>>>>>>> of the source nor on the speed of any medium that
permeates
> : >> the
> : >>>>>> ring.
> : >>>>>>>>
> : >>>>>>>> It is simply NOT TRUE that
> : >>>>>>>> "Nobody has ever directly measured the speed of light in a
> : >>>> vacuum
> : >>>>>> from
> : >>>>>>>> a
> : >>>>>>>> moving source. Nobody. Ever."
> : >>>>>>>
> : >>>>>>>
> : >>>>>>> Balderdash. I said DIRECTLY. Passing the light through a
> window
> : >>>>>>> invalidates a direct measurement.
> : >>>>>>
> : >>>>>> Balderdash. Why does it invalidate it? Let's check some
> numbers.
> : >>>>>> In vacuum, assuming light travels at c, transit time is 3.3
> : >> ns/m.
> : >>>> In a
> : >>>>>> 30 m beamline, the time of flight would be 100 ns. Assuming
> that
> : >>>> light
> : >>>>>> radiated from a highly relativistic electron travels at ~2c,
> the
> : >>>> time
> : >>>>>> of flight in the same beamline would be 50 ns. Therefore the
> : >>>>>> difference
> : >>>>>> to detect is 50 ns.
> : >>>>>>
> : >>>>>> How large an effect can a 1 cm thick quartz window have?
> : >>>>>
> : >>>>> A fucking big one, and the thickess is irrelevant. If you
think
> : >> that
> : >>>>> matters, it shows just how stupid you are. Once the speed
from
> the
> : >>>>> source has been changed, it stays changed.
> : >>>>
> : >>>> OK, let me see if I have this right.
> : >>>
> : >>> Draper , in your case, I will get over my disenchantment.
> : >>>
> : >>> But I want this to be a fruitful exchange between the two of
us,
> so
> : >>> let's not bother agreeing to any ground rules.
> : >>> We'll go things one little step at a time.
> : >>> When we get to a point of conflict, you tell me what it is you
> didn't
> : >>
> : >>> understand,
> : >>> we'll identify what the error is on your side, and I'll let
you
> lie
> : >> and
> : >>> bluster all you want to because I won't even be reading your
> posts.
> : >>>
> : >>>
> : >>>> Light emitted from an electron traveling at nearly c then
travels
> : >> at
> : >>>> nearly 2c,
> : >>>
> : >>> Wrong to begin with.
> : >>>
> : >>> Light emitting from a point of interaction between an electron
and
> a
> : >>> stationary field then travels in vacuum (a reasonable
presumption
> : >> since
> : >>> we have electrons at a large) at an unknown velocity we are
> : >> attempting
> : >>> to determine ....
> : >>
> : >> So the speed of light emitted from a source traveling at v is,
or
> is
> : >> not, c+v? In either case, please make the distinction, if any,
> between
> : >> the case here and the case you fit at
> : >> http://www.androc1es.pwp.blueyonder.co.uk/actual_data.htm which
is
> : >> based on a c+v explanation.
> :
> : This question was unanswered.
> :
> : >>
> : >>>
> : >>>
> : >>>> but upon hitting the window, it gets reduced
> : >>>
> : >>> No, no, not reduced. Changed. We don't know what it is to begin
> with,
> : >>
> : >>> that is what we are trying to measure. Of course, if you've
> already
> : >> made
> : >>> your mind up, I can't help you become a scientist, and you'll
be
> : >>> teaching kids how to become schoolteachers that have
preconceived
> : >> ideas.
> : >>
> : >> OK, so let me ask you a question related to Snell's law. Recall
> : >> Snell's
> : >> law relates a ratio of (sines of) incident and transmitted light
> : >> angles
> : >> to the ratio of speeds in the media, which in turn is the ratio
of
> : >> indices of refraction for that frequency of light.
> : >
> : > You've hit a problem (well, more than one) right there.
> : > 1) the index of refraction is between two media, it is not the
> property
> : > of one.
> :
> : That is incorrect. The refraction occurs at the boundary, but the
> amount of
> : refraction is given by the ratios of the indices of refraction of
the
> two
> : media at the boundary.
>
>
> http://scienceworld.wolfram.com/physics/IndexofRefraction.html
> The index of refraction is defined by
>
> n ~= c/v_phase (1)
>
>
> where c is the speed of light and v_phase is the phase velocity. It
> gives the amount of refraction which takes place for light passing
from
> one medium to another.
>
> Let omega be the angular frequency and k the wavenumber,
then
> the phase velocity is defined as
>
> v_phase = omega/k
>
>
>
> The angular frequency is 2.pi.f.
>
> YOU are incorrect, since you do not know what the speed of light is
and
> nor do you know what the frequency is, since you do not a have a
fucking
> timing device that works fast enough, you pompous arsehole.

Wait, you're telling me I don't KNOW the frequency of visible light
because I can't measure it? And therefore I don't KNOW what the index
of refraction is? So you are claiming index of refraction is an
unmeasurable quantity? Seriously??

How about by Snell's law?
http://scienceworld.wolfram.com/physics/SnellsLaw.html

And in that link we'll just use the equation that they use to determine
the ratio of speeds experimentally, which is based on Fermat's
Principle (unless you want to call THAT into question, too):

sin(theta_1) / v_1 = sin(theta_2) / v_2, where the theta is the angle
of the light with respect to the normal to the surface in each medium,
and the v is the velocity of the light in that medium.

>
>
>
>
>
> : >
> : > For example, the fish tank. Light passes from the water to the
glass
> to
> : > the air.
> : >
> : > 2) You seem to be saying that blue light travels faster than red
> light
> : > in a medium.
> :
> : Actually, the other way around. Blue light generally travels slower
> than red
> : light in a medium.
>
>
> Oh, I see. The faster bullet bends more at the interface. Gotcha.

Uh, no. How did you arrive at that conclusion?

>
>
> : This is how glass prisms work to create spectra and how
> : water droplets work to create rainbows.
>
> Oh, I see. Having further to go in the medium, the blue travels
slower
> than the
> red, does it?
>
> http://hyperphysics.phy-astr.gsu.edu/hbase/imgmod/roygbv.gif
> http://www-staff.lboro.ac.uk/~huph/Prism3.gif

The picture is right. Your interpretation is wrong, and it is a classic
student mistake. The refraction happens at each boundary. The ray
doesn't know how much glass it has to traverse to get to the other
side, so it can't make a decision at the boundary where it has to point
to get to the other side earlier or later. In fact, it's a mistake to
think that the blue wavefronts have to "keep up" with the red
wavefronts. They don't, and they don't emerge from the prism at the
same time. As for what's correct, look at the picture and look at the
formula I gave above.

sin(theta_1) / v_1 = sin(theta_2) / v_2

For region 1 being air and 2 being glass (light entering glass), the
change in sin(theta) is larger for blue light than it is for red light
(see picture), which means that the change in speed is larger for blue
light than it is for red light, which means that blue light slows down
more in glass than red light does.

If you can't see it algebraically, then measure your GIF files with a
protractor and figure out the numbers involved. Or do a Google search
for "prism applet", which will calculate all these numbers for you.

>
>
>
>
> : It also is responsible for chromatic
> : aberration in the eye, which in turn is behind the claim by the
makers
> of
> : Blu-Blocker sunglasses that their product improves clarity of
vision.
>
> Oh really.... gotcha. Thank goodness I was never in your fucking
class.

So are you agreeing or disagreeing, or just refusing to believe
anything I say out of principle?

>
> : >
> : > We have more than one speed of light, and there cannot be just
one
> : > characteristic permeability amd one permittivity for the material
in
> : > question if you wish to uphold Maxwell's approximations....
err...
> : > "laws".
> : >
> : > I'm not too sure what Maxwell did for us, anyway.
> : > Gauss' Law, curl B = dE/dt and Faraday's Law, curl E = -dB/dt
> : > a) seem to be all we need to describe light in a vacuum and
> : > b) assume time is invariant.
> : >
> : > Amperes' Law.... curl B = J. Later modified to
> : >
> : > curl H = J + dD/dt
> : >
> : > Ampere's law, modified form
> : > The line integral of the magnetic field around a closed curve is
> : > proportional to the sum of two terms: first, the algebraic sum of
> : > electric currents flowing through that closed curve;
> : >
> : >
> : > There is no closed curve in a vacuum for the electric current to
> flow
> : > in, so we can forget that.
> : >
> : > In addition to describing electromagnetism, Maxwell's equations
also
> : > claim that waves can propagate through the electromagnetic field,
> and
> : > would always propagate at the same speed -- these are
> electromagnetic
> : > waves; the speed can be found by computing (epsilon0 mu0)-1/2,
which
> is
> : > c, the speed of light in Maxwell's aether, which doesn't exist.
So
> along
> : > come the bright sparks and instead of discarding Maxwell along
with
> the
> : > aether, transfer its properties to nothing.
> : > Seems that physics is more about paying homage to the more famous
> : > plagiarists than about studying Nature.
> :
> : I'm not sure what the point of the preceding monologue about
Maxwell's
> : equations has been. What's your point, exactly?
>
> You fucking thick quartz window and you fucking thick quartz head.
Never
> mind, it went right over the top anyway. Go back to sleep.

Right, OK.

>
>
>
>
> :
> : >
> : > 3) Attenuation. Sunlight doesn't penetrate the depths of the
ocean,
> : > lamps were take to illuminate the Titanic. Red light penetrates
> further
> : > than blue, we see red sunrises and sunsets. Blue light is
scattered,
> : > giving us a blue sky.
> : > Is the light slowing down in the medium?
> :
> : What does attenuation due to scattering in a medium have to do with
> the
> : speed of transmission through the medium?
>
> Ahh.... woken up at last, have you? Tell us, smart arse, what does
> attenuation
> have to do with the sun setting, the red light being faster than the
> blue? C'mon, you fucking know everthing, you tell me, I'll have a
good
> laugh.

Attenuation due to scattering has a lot to do with the color of
sunrises and sunsets. It has nothing to do, as far as I can tell, with
the speed of the light in the medium.

>
>
> : >
> : > A lemma of this law
> : >> says that if you have a window embedded in another medium so
that
> the
> : >> light is going from medium A to B and then back to A on the
other
> : >> side,
> : >> then the outgoing speed (in A) and the outgoing angle (in A) is
the
> : >> same as the incoming speed (in A) and the incoming angle (in A).
> But
> : >> you don't seem to be saying quite that.
> : >
> : > Well, have you got a vacuum on both sides of the window, then? If
> so,
> : > what do you need the window for? Throw it away.
> :
> : As I indicated below, many experiments do exactly that, dispensing
> with your
> : objection that the measurement of flight time is corrupted by the
> presence
> : of a window.
>
> As you guessed below, you mean. I think you are making it up. I
think
> you are bullshitting. I think you are a schoolteacher that has never
> been near a storage ring in his life.

And you would be wrong.

>
>
> : >
> : >> For the sake of argument, let's
> : >> suppose we have a situation where A is vacuum and B is quartz.
> : >
> : > Then the light enters the quartz at whatever speed it has,
travels
> : > through the quartz
> : > with the characteristic speed of light in quartz, and leaves with
> the
> : > characteristic speed of light in quartz. There is nothing else to
> change
> : > it (actually, there is).
> : > The last thing the light encountered was an electron attached to
the
> : > last molecule of the quartz.
> : > But anyway, that's for materials research, we are concerned with
the
> : > speed of light in vacuum.
> :
> : OK, let me see if I have this right.
> :
> : If light (and for easy look-up of numbers, let's use visible light)
> passes
> : from quartz (n = 1.5) to vacuum (n = 1), there would be no
refraction
> at the
> : boundary at all, because the speed of the light in the quartz as it
> : approaches the boundary is identical to the speed of the light in
the
> vacuum
> : as it departs from the boundary. Snell's law would not work in this
> case.
>
>
> That right, it wouldn't. But you've never tested it. So do a
Michelson,
> say "We know what will happen", try it and find that it doesn't. Of
> course, you'd need to be honest like Michelson as well. You don't
have
> that kind of honesty. You are the kind of guy that who will say
"They
> take the windows out for some experiments".
> because you appearing to be right is more important to you than
> spreading dis-information, right?

Actually, I don't have to do "a Michelson". Beamlines are surveyed with
lasers and, if they're long, while evacuated, because thermal gradients
in air cause light bending. Special windows are used for this process
by some surveying teams, and if there is an angular offset, they have
to account for the dogleg in the beam of light due to the refraction.
The amount of dogleg is proportional to the refraction bend at the
transition between vacuum and window. If they don't correct for it
(which they would not do if your model was correct), the beam center
would be off by several millimeters, which is easily detectable by
charged particle detectors when beam comes down the line. So, yes, it's
been tested. I'm sure this is not the only test that's been done.

When a model comes up against experimental observations the contrary,
you have to dispense with the model.

>
>
> : On the other hand, if light passes from quartz (n = 1.5) to air (n
=
> : 1.0003), there would be substantial refraction because the speed of
> light in
> : the quartz is substantially lower than the speed of light in air,
in
> : accordance with Snell's Law.
> :
> : And so if I attenuate the air so that it steadily becomes more and
> more
> : vacuum-like (n decreasing from 1.0003 to 1.000000000...) at some
> point,
> : refraction suddenly snaps off because the speeds in the two media
> become
> : identical.
> :
> : Is that what your model says?
>
> Suddenly snaps off? What hat did you pull a step function from?

Simple. Snell's law. Try this little simulation
http://www.physics.nwu.edu/ugrad/vpl/optics/snell.html
n1*sin(theta1) = n2*sin(theta2)
So sin(theta2) = (n1/n2)*sin(theta1)

If n1 = 1.5 and n2 = 1.0003, then n1/n2 = 1.49955.
If n2 = 1.5 and n2 = 1.00000000...., then n1/n2 = 1.5
By my model, there is a smooth transition in sin(theta2)/sin(theta1)
with a pump-out from 1.49955 to 1.5
By your model, as soon as the other side is vacuum, then suddenly there
is no refraction and sin(theta2)/sin(theta1) = 1.

>
>
> If not, then what DOES your model say about
> : these two cases?
>
> Well, let's see... how many metres is it from the window to the next
air
> molecule, be it oxygen, nitrogen, carbon dioxide, methane, or some
> other trace element, and which one has the refractive index 1.003 as
you
> gradually attenuate the air?
> Oh, and what was the temperature of that molecule?

I don't know. Is that your model? That's what I asked you about.

>
> : >>>> to something
> : >>>> less than c, and then when it emerges from the window it stays
at
> : >> the
> : >>>> speed it had in the window?
> : >>>
> : >>> No, no, it gets changed again, this time to its characteristic
> : >> velocity
> : >>> in air.
> : >>> Otherwise there was no point in having a window, was there?
> : >>
> : >> Unless, of course, there is more vacuum on the other side of the
> : >> window. The detectors are not necessarily in air.
> : >
> : > Then take the window out or put the detector inside the storage
> ring.
> : > It won't do much good, though, the proximity of the metal will
> affect
> : > the EM field, as we know from inexpensive metal detectors that
> people
> : > are using to dig up 1600 to 2000-year-old Roman coins all over
> Britain.
> : > Then you've still got the problem of proving the light comes from
> the
> : > electron and not the point of interaction.
> :
> : Don't you have the same problem of proving that the light comes
from
> the
> : star and not the point of interaction?
>
> No.
>
> See
> : http://www.androc1es.pwp.blueyonder.co.uk/actual_data.htm
> : What's different about your orbiting star case and this orbiting
> electron
> : case?
>
> I don't think anyone is claiming that sunlight/starlight is caused
by
> the sun passing through an external magnetic field, but if that is
your
> claim I'll discuss it with y.... hhmm... no I won't. There are
limits
> to which I will not go beyond, although you seem to be able to make
up
> any kind of preposterous crap to try to win a debate.

Hey, it's your model. Thought you'd be prepared to defend it,
especially since it is so radically new and different. But if you don't
care about it....

>
>
>
> : >
> : > Nobody has ever directly measured the speed of light in a vacuum
> : > from a moving source. Nobody. Ever.
> : >
> : > The nearest anyone ever came to it is Henri Wilson and myself,
but
> that
> : > only crudely demonstrates the principle.
> : >
> : >>
> : >>>
> : >>> I guess its a shame, but you'll have to tell those cretins that
> : >> designed
> : >>> the ring
> : >>> it was a total waste of time with those windows in place. We
need
> to
> : >>
> : >>> make the measurement in the vacuum, especially for short
> distances.
> : >>> Of course it may be difficult evacauting the entire building
after
> : >>> everyone has set up
> : >>> their intrumentation, but .... too bad.
> : >>> If the experiment is worth doing, its worth doing properly.
> : >>
> : >> Actually, if you study the documentation carefully, you'll note
> that
> : >> the vacuum pipe often extends to, and includes the
instrumentation.
> : >> So-called Roman pots are an example of a technique used to put
> : >> instrumentation directly in the beamline in vacuo. Indeed, for
many
> : >> experiments and beamlines, a window would be a disaster, as it
> would
> : >> cause diffraction, ejected electrons from the window, etc.
> : >
> : >
> : > So prove the electrons are the source of the light.
> : > I say it is the point of interaction between the stationary field
> and
> : > the electron.
> :
> : And is this an instantaneous interaction in your view?
>
> I have no idea. How long does it take for an electron to pass (at
> "nearly the speed of light" as you claim) through the steering
magnet's
> field?

A little while.
And yes, it makes a difference. An instantaneous reaction happens at a
particular place and time, no extent in either dimension. For something
to be stationary, it has to occupy the same place for an extended time.
An instantaneous event can't be called stationary or moving.

>
>
> If not not, is the
> : point of interaction stationary or moving?
>
> I don't think anyone is sliding the steering magnets up and down the
> length of the tube, do you?

No, but you're claiming the point of interaction is stationary. So I
suppose it's not instantaneous. So now all we have to determine is
whether the emitted photon is emitted from the electron, from the
field, or from the magnet. So, which is it?

>
> Why am I wasting my time on a fucking useless imbecile anyway ?
> Androcles.
>

[dead ends snipped]

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