On Jan 2, 1:05*pm, PD wrote:
On Jan 2, 11:13*am, kenseto wrote:





On Jan 2, 10:48*am, PD wrote:

See? You say it only applies to sources at rest with respect to the
grating and then say it is universal. Poor use of the word universal.

But the sodium atoms are not at rest wrt the grating when they are
heated. The result is that they reach a average velocity of V_t wrt
the grating and 588.995 nm is the wavelength of the center line of V_t
in every frame. Therefore this special wavelength is the universal
wavelength for that special line of sodium.

Those atoms that are not at rest wrt the grating do not exhibit light
with a wavelength at 588.995 nm. You and I have both said that.

When the sodium is heated no atom is at rest wrt the grating.

Well, actually, that's not true either. Even in a hot gas, some atoms
are not moving relative to the grating. The atoms in a gas at a
particular temperature have a *distribution* of velocities relative to
the grating. That *distribution* is centered around 0 and there very
definitely are atoms in that distribution that are sitting at 0. You
know what a distribution is?

No...every heated sodium atom is in a state of relative motion wrt the
whole of the grating.

Sorry, but you obviously don't know what a thermal distribution looks
like.

However, this is irrelevant. What is relevant is
that there is a distinct line that has a universal wavelength of
588.995 nm

No, it doesn't. Why are you repeating the same incorrect statement?
Where did you read such nonsense?

So where is the wavelength of 588.995 nm for sodium come from? BTW you
claimed that this wavelength is the result of those sodium atoms at
rest wrt the grating. The sodium also have another wavelength 590.58nm
is this wavelength aslo come from those sodium atoms at rest wrt the
grating?





and this line is caused by those sodium atoms that has a
relative velocity of V_t wrt the grating.

This
is why there isn't a line specifically at 588.995 nm, but instead a
*range* of wavelengths *centered* on 588.995 nm. There is no
*definition* of sodium light being at 588.995 nm; I don't know where you got the impression or read any differently.

This is irrelevant. We known that when the sodium is heated in the
frame of the grating there is a line in the spectrum that has a
universal wavelength of 588.995 nm.

No, you don't know that at all. Where on earth did you get the idea
that there is a line in the spectrum that has a universal wavelength
of 588.995 nm?

Because the grating measures it to be so?

No, it doesn't. Where on earth did you get the idea that it does that?

So the grating doesn't measure sodium to have a wavelength of 588.995
nm? Then why did you agree previously that every observer measures his
sodium source to have a wavelength of 589 nm????





It isn't bad science if that's what's actually observed.

Sure it is bad science....what is actually observed is a new light
source in the frame of the grating and thus the grating defines a new
wavelength for it.

You are
saying that the universe cannot possibly behave that way, and that you
would prefer it if it behaved a way that makes more sense to you. That
is not good science.

No....you made the wrong assumption and continued to assert that your
assumption is correct.

I'm not making any assumption. I'm taking the wavelength to be what
it's measured to be, which is NOT 589 nm.

It was you who first told me that the wavelength of sodium have a
wavelength of 589 nm.

You instead say that, even
though the wavelength is not measured to be 589 nm, it is nonetheless
589 nm, because you would prefer to assume that than to assume that
the speed of light is invariant. Thus you are changing a wavelength
from what is measured to a value other than that. That's bad, bad
science.

The incoming sodium light becomes a different light source so the
grating defines a new wavelength for it.



It is ALWAYS a bad idea to prefer something that is in conflict with
measurement.

But my assumption is based on valid reasoning and your assumption is
based on the bogus idea that light changes speed during transit from
the source to the observer.

Sorry, Ken, valid reasoning does not trump measurement in science.
Never has, never will. If you have valid reasoning that says something
other than what measurement says, then your valid reasoning is simply
wrong nevertheless.

Wavelength doen't change during transit. Light speed change due to
motion of the observer wrt the incoming light rays.


Valid reasoning does not make good science. Valid reasoning and 75
cents will buy you a cup of coffee. Valid reasoning that also happens
to agree with measurement, on the other hand, is extremely valuable.
Changing measured values to conform with what you think is valid
reasoning is not only worthless, but it is scientific fraud.

I did not change any measured value. The grating defines a different
wavelength for different light ray passing through it. The incoming
sodium light is a different light ray in so far as the grating is
concerned.




No, that observer does measure the light speed to be c relative to the
source. But that isn't what the other observer sees.

So what is the observer at the source frame measures the speed of his
light source to be?

On average, zero. Why?

??????are you saying that he doen't maeasure his own light to have a
speed of c????



You are
suggesting the speed changes because you're comparing it in two
different reference frames.

In SR the speed of light is a universal constant c. So what is wrong
by saying that the speed of light is c in the source frame and it is
also c in the observer's frame?????


There's nothing wrong with that. The problem is you then conclude that
the speed had to change in between.

But the source and the observer are in a relative motion. That means
that the incoming light must change speed during transit to eliminate
the effect of relative motion so that it can be detected as arriving
at the observer at the same speed of c as measured by the source
observer.

By the way, light "in the source frame" doesn't talk just about the
light in the vicinity of the source, and light "in the observer frame"
doesn't talk just about the light in the vicinity of the observer.
It's not like light is traveling from one reference frame to another
reference frame. The same light is in *BOTH reference frames for the
ENTIRE trip. You seem to have a difficult time understanding what a
reference frame is.



You are thinking that if the speed of
light leaving the source is c, as seen by the observer at the source,
then it can't be c as viewed by an observer moving at relative speed u
wrt to the source.

That would be a valid reasoning but SR said that the observer also
measures the incoming light from the source to be c. So the only way
this can happen is that the speed of light changes during transit to
eliminate the effect of relative motion between the source and the
observer.

What "effect of relative motion"?

The effect is:
The transit time for a light ray to reach a moving object moving
toward you is shorter because the effect of relative motion between
you and the object is added to the speed of light.



If it is c as viewed by an observer moving at
relative speed u wrt to the source, then the speed of light must have
changed, according to you. Perhaps you think that the speed of light
as viewed by the second observer should be c+u or c-u.

NO....I don't think that at all.

Then what's the "effect of relative motion" that you think needs to be
eliminated by a change in the speed of light?

I think that the speed of light is a
constant math ratio in all frames as follows:
Light path length of ruler (299,792,458 meters long physically)/the
absolute time content for a clock second co-moving with the ruler.

That would be a mistake. Velocities don't combine by simple addition
or subtraction. Why do you think that they do?

Yes light velocities don't combine by simple addition or substraction
because light is being transmitted by the E-Matrix at a max. constant
speed of c.

They don't combine by simple addition or subtraction anyway, even
without the E-matrix.


Without the E-Matrix simple addition and subtraction of speed will
work fine. With the E-Matrix the max speed is the speed of
transmission by the E-Matrix.

Ken Seto

On Jan 3, 10:37*am, kenseto wrote:
On Jan 2, 1:05*pm, PD wrote:


See? You say it only applies to sources at rest with respect to the
grating and then say it is universal. Poor use of the word universal.

But the sodium atoms are not at rest wrt the grating when they are
heated. The result is that they reach a average velocity of V_t wrt
the grating and 588.995 nm is the wavelength of the center line of V_t
in every frame. Therefore this special wavelength is the universal
wavelength for that special line of sodium.

Those atoms that are not at rest wrt the grating do not exhibit light
with a wavelength at 588.995 nm. You and I have both said that.

When the sodium is heated no atom is at rest wrt the grating.

Well, actually, that's not true either. Even in a hot gas, some atoms
are not moving relative to the grating. The atoms in a gas at a
particular temperature have a *distribution* of velocities relative to
the grating. That *distribution* is centered around 0 and there very
definitely are atoms in that distribution that are sitting at 0. You
know what a distribution is?

No...every heated sodium atom is in a state of relative motion wrt the
whole of the grating.

Sorry, but you obviously don't know what a thermal distribution looks
like.

However, this is irrelevant. What is relevant is
that there is a distinct line that has a universal wavelength of
588.995 nm

No, it doesn't. Why are you repeating the same incorrect statement?
Where did you read such nonsense?

So where is the wavelength of 588.995 nm for sodium come from?

It comes from putting a mark at the *center* of a distribution of
wavelengths that comprise a "line" from a *particular* sodium source,
one that is at rest relative to the observer. A spectrographic line is
not a single-wavelength line, it is a *band*. Putting a mark in the
center of that band no more tells you what the wavelengths in that
band are than putting a thumbtack in a map of the US at Xenia tells
you where Ohio is. (The folks in Toledo or Columbus would beg to
differ.)

Moreover, this doesn't apply AT ALL for other sodium sources that are
not at rest relative to the observer. Other sodium sources do not
exhibit ANY line at 588.995 nm, but they are sodium nevertheless.

So the line sometimes marked at 588.995 nm only applies to some sodium
sources, not all -- and therefore 588.995 nm is not universal. And in
fact, even for sodium sources where there is a line at 588.995 nm,
most of the light in that line comes from a little less or a little
more than 588.995 nm, just like most of Ohio is a little east or a
little west of where the thumbtack is stuck in Xenia. 588.995 nm just
happens to be in the middle of that narrow band called a spectral
line.

BTW you
claimed that this wavelength is the result of those sodium atoms at
rest wrt the grating. The sodium also have another wavelength 590.58nm
is this wavelength aslo come from those sodium atoms at rest wrt the
grating?


Yes. Sodium has a *bunch* of spectral lines from a source at rest. All
elements have more than one line from a source at rest.
http://www.amateurspectroscopy.com/C...um-Krypton.jpg
If you had the slightest idea how a spectrograph worked, or if you'd
ever used one, none of this would be a mystery to you.
How did you get a chemical engineering degree without having done
this?


and this line is caused by those sodium atoms that has a
relative velocity of V_t wrt the grating.

This
is why there isn't a line specifically at 588.995 nm, but instead a
*range* of wavelengths *centered* on 588.995 nm. There is no
*definition* of sodium light being at 588.995 nm; I don't know where you got the impression or read any differently.

This is irrelevant. We known that when the sodium is heated in the
frame of the grating there is a line in the spectrum that has a
universal wavelength of 588.995 nm.

No, you don't know that at all. Where on earth did you get the idea
that there is a line in the spectrum that has a universal wavelength
of 588.995 nm?

Because the grating measures it to be so?

No, it doesn't. Where on earth did you get the idea that it does that?

So the grating doesn't measure sodium to have a wavelength of 588.995
nm? Then why did you agree previously that every observer measures his
sodium source to have a wavelength of 589 nm????

Because 589 nm is a good marker for the *center* of that line. But
most of the line corresponds to wavelengths a little more or a little
less than that number. And that only works for one kind of sodium
source -- the one at rest -- and doesn't work at all for any other
sodium source. Anything that only works for one kind of something and
not for any other kind of the same thing is not universal. You are the
one that always and incorrectly uses the word "universal". I've never
used that word to describe it, because it's wrong.


It isn't bad science if that's what's actually observed.

Sure it is bad science....what is actually observed is a new light
source in the frame of the grating and thus the grating defines a new
wavelength for it.

You are
saying that the universe cannot possibly behave that way, and that you
would prefer it if it behaved a way that makes more sense to you. That
is not good science.

No....you made the wrong assumption and continued to assert that your
assumption is correct.

I'm not making any assumption. I'm taking the wavelength to be what
it's measured to be, which is NOT 589 nm.

It was you who first told me that the wavelength of sodium have a
wavelength of 589 nm.

No, I didn't. I gave you an explicit example of a sodium source that
did NOT have a wavelength of 589 nm. You have selective memory, even
when reminded. You only remember what you want to remember.

Look up what I told you and remind yourself exactly what I said.


You instead say that, even
though the wavelength is not measured to be 589 nm, it is nonetheless
589 nm, because you would prefer to assume that than to assume that
the speed of light is invariant. Thus you are changing a wavelength
from what is measured to a value other than that. That's bad, bad
science.

The incoming sodium light becomes a different light source so the
grating defines a new wavelength for it.

Nope. If the grating measures a wavelength of 614.326 nm for the
sodium source, then that is the wavelength of that sodium source. It
is still a sodium source (which is recognized by the *spacing* of the
lines, not the wavelengths) and it has a wavelength of 614.326 nm, NOT
588.995 nm. If you say, "To hell with 614.326 nm, it must be 588.995
nm anyway," that's exceedingly bad science.


It is ALWAYS a bad idea to prefer something that is in conflict with
measurement.

But my assumption is based on valid reasoning and your assumption is
based on the bogus idea that light changes speed during transit from
the source to the observer.

Sorry, Ken, valid reasoning does not trump measurement in science.
Never has, never will. If you have valid reasoning that says something
other than what measurement says, then your valid reasoning is simply
wrong nevertheless.

Wavelength doen't change during transit. Light speed change due to
motion of the observer wrt the incoming light rays.

Repeating an error doesn't make it right. The wavelength is *measured*
to be different than 588.995 nm, so it IS different than 588.995 nm.

You cannot insist that it must nevertheless be 588.995 nm, just
because you don't understand how it could be different than 588.995
nm. The experiment tells you it IS different, and you see it with your
own eyes. At least, you do if you actually do the experiment.


Valid reasoning does not make good science. Valid reasoning and 75
cents will buy you a cup of coffee. Valid reasoning that also happens
to agree with measurement, on the other hand, is extremely valuable.
Changing measured values to conform with what you think is valid
reasoning is not only worthless, but it is scientific fraud.

I did not change any measured value. The grating defines a different
wavelength for different light ray passing through it. The incoming
sodium light is a different light ray in so far as the grating is
concerned.

No, it's not. It's the same light ray. There's absolutely nothing
between the source and the grating. The grating measures the
wavelength of the light ray DIRECTLY. It's your favorite kind of
measurement -- the direct one.


No, that observer does measure the light speed to be c relative to the
source. But that isn't what the other observer sees.

So what is the observer at the source frame measures the speed of his
light source to be?

On average, zero. Why?

??????are you saying that he doen't maeasure his own light to have a
speed of c????

That's not what you asked. You asked about the speed of the light
*source*, not the speed of the light from the source.


You are
suggesting the speed changes because you're comparing it in two
different reference frames.

In SR the speed of light is a universal constant c. So what is wrong
by saying that the speed of light is c in the source frame and it is
also c in the observer's frame?????

There's nothing wrong with that. The problem is you then conclude that
the speed had to change in between.

But the source and the observer are in a relative motion. That means
that the incoming light must change speed during transit to eliminate
the effect of relative motion so that it can be detected as arriving
at the observer at the same speed of c as measured by the source
observer.

See below. I've asked you what you think the effect of relative motion
is. I'll answer it below where you tell me that.


By the way, light "in the source frame" doesn't talk just about the
light in the vicinity of the source, and light "in the observer frame"
doesn't talk just about the light in the vicinity of the observer.
It's not like light is traveling from one reference frame to another
reference frame. The same light is in *BOTH reference frames for the
ENTIRE trip. You seem to have a difficult time understanding what a
reference frame is.

You are thinking that if the speed of
light leaving the source is c, as seen by the observer at the source,
then it can't be c as viewed by an observer moving at relative speed u
wrt to the source.

That would be a valid reasoning but SR said that the observer also
measures the incoming light from the source to be c. So the only way
this can happen is that the speed of light changes during transit to
eliminate the effect of relative motion between the source and the
observer.

What "effect of relative motion"?

The effect is:
The transit time for a light ray to reach a moving object moving
toward you is shorter because the effect of relative motion between
you and the object is added to the speed of light.


No, and that's precisely the point. You do not ADD the relative motion
between you and the object to the speed of light. Speeds do not
combine by adding or subtracting. They just don't.

Let's call the relative motion between you and the source by a letter
u. You are saying that the effect of the relative motion between you
and the object should be to add u to c, like this: c+u. And then you
are saying that c+u has to change to c sometime in flight, so that the
observer sees the speed of light to be c.

But that's wrong. Speeds do not combine by adding them.

They add a different way. They add like this:
(c+u)/(1+c*u/c^2).
Now figuring out how much this is, is simple algebra. Can you simplify
the above expression?


If it is c as viewed by an observer moving at
relative speed u wrt to the source, then the speed of light must have
changed, according to you. Perhaps you think that the speed of light
as viewed by the second observer should be c+u or c-u.

NO....I don't think that at all.

Then what's the "effect of relative motion" that you think needs to be
eliminated by a change in the speed of light?

I think that the speed of light is a
constant math ratio in all frames as follows:
Light path length of ruler (299,792,458 meters long physically)/the
absolute time content for a clock second co-moving with the ruler.

That would be a mistake. Velocities don't combine by simple addition
or subtraction. Why do you think that they do?

Yes light velocities don't combine by simple addition or substraction
because light is being transmitted by the E-Matrix at a max. constant
speed of c.

They don't combine by simple addition or subtraction anyway, even
without the E-matrix.

Without the E-Matrix simple addition and subtraction of speed will
work fine.

No, it doesn't. That's just the point. Even without the E-Matrix,
simple addition and subtractions of speeds do not work fine. They give
answers that are different than what is actually measured.

With the E-Matrix the max speed is the speed of
transmission by the E-Matrix.

Ken Seto

"kenseto" wrote in message
...
So where is the wavelength of 588.995 nm for sodium come from? BTW you
claimed that this wavelength is the result of those sodium atoms at
rest wrt the grating. The sodium also have another wavelength 590.58nm
is this wavelength aslo come from those sodium atoms at rest wrt the
grating?

Why are you so obseessed with sodium?

On Jan 3, 4:38*pm, "Jeckyl" wrote:
"kenseto" wrote in message

...

So where is the wavelength of 588.995 nm for sodium come from? BTW you
claimed that this wavelength is the result of those sodium atoms at
rest wrt the grating. The sodium also have another wavelength 590.58nm
is this wavelength aslo come from those sodium atoms at rest wrt the
grating?

Why are you so obseessed with sodium?

Because it's the only spectroscopy example he knows, and it comes from
a lesson I gave him in a post last summer. He's repeatedly mentioned
that the only thing he knows about this is what I've told him, and so
it's frustrating to him when I tell him that he still doesn't have it
right. What's interesting about this, of course, is that he wrote his
paper about the E-Matrix and has written further papers about his
explanation of the Doppler effect, all *before* I explained the first
thing about spectroscopy to him. This means that he wrote those papers
while knowing *nothing* about spectroscopy -- except possibly what he
read in A Brief History of Time or other coffee table books. It hasn't
occurred to him that it's hazardous to write a paper about a subject
that he knows absolutely nothing about. I imagine he heard that
Einstein's original paper didn't have any references on it, and he
guessed (wrongly) that Einstein wrote it without reading anything that
informed his thinking; therefore if Einstein could do it, then Seto
could do it. The only significant problem now is that he's got a lot
of time and effort invested in this monumental (not to mention
outlandishly presumptuous) mistake, and so it would be quite painful
to simply chuck all that in the dustbin and start again.

PD

On Jan 3, 2:14*pm, PD wrote:
On Jan 3, 10:37*am, kenseto wrote:





On Jan 2, 1:05*pm, PD wrote:


Sorry, but you obviously don't know what a thermal distribution looks
like.

However, this is irrelevant. What is relevant is
that there is a distinct line that has a universal wavelength of
588.995 nm

No, it doesn't. Why are you repeating the same incorrect statement?
Where did you read such nonsense?

So where is the wavelength of 588.995 nm for sodium come from?

It comes from putting a mark at the *center* of a distribution of
wavelengths that comprise a "line" from a *particular* sodium source,
one that is at rest relative to the observer.

Since sodium when heated has two *centers* of distributions of
wavelengths are you saying the both of these *centers* are generated
by sodium atoms at rest wrt the grating? How is that possible?


BTW you
claimed that this wavelength is the result of those sodium atoms at
rest wrt the grating. The sodium also have another wavelength 590.58nm
is this wavelength aslo come from those sodium atoms at rest wrt the
grating?

Yes. Sodium has a *bunch* of spectral lines from a source at rest.

But all the sodium atoms are in a state of relative motion wrt the
grating when heated. Furthermore how can you have two centers of lines
and the atoms that generated both centers are at rest wrt the
gratings.
No, it doesn't. Where on earth did you get the idea that it does that?

I'm not making any assumption. I'm taking the wavelength to be what
it's measured to be, which is NOT 589 nm.

It was you who first told me that the wavelength of sodium have a
wavelength of 589 nm.

No, I didn't. I gave you an explicit example of a sodium source that
did NOT have a wavelength of 589 nm. You have selective memory, even
when reminded. You only remember what you want to remember.

Look up what I told you and remind yourself exactly what I said.



You instead say that, even
though the wavelength is not measured to be 589 nm, it is nonetheless
589 nm, because you would prefer to assume that than to assume that
the speed of light is invariant. Thus you are changing a wavelength
from what is measured to a value other than that. That's bad, bad
science.

The incoming sodium light becomes a different light source so the
grating defines a new wavelength for it.

Nope. If the grating measures a wavelength of 614.326 nm for the
sodium source, then that is the wavelength of that sodium source.
It
is still a sodium source (which is recognized by the *spacing* of the
lines, not the wavelengths) and it has a wavelength of 614.326 nm, NOT
588.995 nm. If you say, "To hell with 614.326 nm, it must be 588.995
nm anyway," that's exceedingly bad science.

No it is a new source the telescope that collects the light ray and
direct it to the grating acts as a new light source in the frame of
the grating. That's why the grating measures a new wavelength for it.
If it is sodium then the grating would have measure a wavelength of
588.995 nm.



Sorry, Ken, valid reasoning does not trump measurement in science.
Never has, never will. If you have valid reasoning that says something
other than what measurement says, then your valid reasoning is simply
wrong nevertheless.

Wavelength doen't change during transit. Light speed change due to
motion of the observer wrt the incoming light rays.

Repeating an error doesn't make it right. The wavelength is *measured*
to be different than 588.995 nm, so it IS different than 588.995 nm.

The incoming sodium light becomes a new light source in the frame of
the grating. This is true no matter how you scream and cry foul.


You cannot insist that it must nevertheless be 588.995 nm, just
because you don't understand how it could be different than 588.995
nm. The experiment tells you it IS different, and you see it with your
own eyes. At least, you do if you actually do the experiment.

It is a much better concept than to assume that the incoming sodium
light is arriving at a constant c. Such assumption require light to
change speed during transit to eliminate the effect of relative motion
between the source and the observer.



Valid reasoning does not make good science. Valid reasoning and 75
cents will buy you a cup of coffee. Valid reasoning that also happens
to agree with measurement, on the other hand, is extremely valuable.
Changing measured values to conform with what you think is valid
reasoning is not only worthless, but it is scientific fraud.

I did not change any measured value. The grating defines a different
wavelength for different light ray passing through it. The incoming
sodium light is a different light ray in so far as the grating is
concerned.

No, it's not. It's the same light ray. There's absolutely nothing
between the source and the grating. The grating measures the
wavelength of the light ray DIRECTLY. It's your favorite kind of
measurement -- the direct one.

Yes there is something between the source and the grating....the
telescope that clooect the sodium light from the source.



No, that observer does measure the light speed to be c relative to the
source. But that isn't what the other observer sees.

So what is the observer at the source frame measures the speed of his
light source to be?

On average, zero. Why?

??????are you saying that he doen't maeasure his own light to have a
speed of c????

That's not what you asked. You asked about the speed of the light
*source*, not the speed of the light from the source.

I said the speed of light in the source frame.




Ken Seto

On Jan 4, 11:25*am, kenseto wrote:
On Jan 3, 2:14*pm, PD wrote:

Sorry, but you obviously don't know what a thermal distribution looks
like.

However, this is irrelevant. What is relevant is
that there is a distinct line that has a universal wavelength of
588.995 nm

No, it doesn't. Why are you repeating the same incorrect statement?
Where did you read such nonsense?

So where is the wavelength of 588.995 nm for sodium come from?

It comes from putting a mark at the *center* of a distribution of
wavelengths that comprise a "line" from a *particular* sodium source,
one that is at rest relative to the observer.

Since sodium when heated has two *centers* of distributions of
wavelengths are you saying the both of these *centers* are generated
by sodium atoms at rest wrt the grating? How is that possible?

Oh, geez, Ken. Do I have to explain to you why a single atom radiates
more than one wavelength? Can't you google that yourself? Didn't you
cover this in your *first semester* chemistry class?
Try googling "atomic emission applet".

I can't believe you're trying to understand Doppler shift when you
don't have the foggiest idea where an emission spectrum comes from.


BTW you
claimed that this wavelength is the result of those sodium atoms at
rest wrt the grating. The sodium also have another wavelength 590.58nm
is this wavelength aslo come from those sodium atoms at rest wrt the
grating?

Yes. Sodium has a *bunch* of spectral lines from a source at rest.

But all the sodium atoms are in a state of relative motion wrt the
grating when heated. Furthermore how can you have two centers of lines
and the atoms that generated both centers are at rest wrt the
gratings. *





No, it doesn't. Where on earth did you get the idea that it does that?

I'm not making any assumption. I'm taking the wavelength to be what
it's measured to be, which is NOT 589 nm.

It was you who first told me that the wavelength of sodium have a
wavelength of 589 nm.

No, I didn't. I gave you an explicit example of a sodium source that
did NOT have a wavelength of 589 nm. You have selective memory, even
when reminded. You only remember what you want to remember.

Look up what I told you and remind yourself exactly what I said.

You instead say that, even
though the wavelength is not measured to be 589 nm, it is nonetheless
589 nm, because you would prefer to assume that than to assume that
the speed of light is invariant. Thus you are changing a wavelength
from what is measured to a value other than that. That's bad, bad
science.

The incoming sodium light becomes a different light source so the
grating defines a new wavelength for it.

Nope. If the grating measures a wavelength of 614.326 nm for the
sodium source, then that is the wavelength of that sodium source.
It
is still a sodium source (which is recognized by the *spacing* of the
lines, not the wavelengths) and it has a wavelength of 614.326 nm, NOT
588.995 nm. If you say, "To hell with 614.326 nm, it must be 588.995
nm anyway," that's exceedingly bad science.

No it is a new source the telescope that collects the light ray and
direct it to the grating acts as a new light source in the frame of
the grating.

There is no telescope required. You can do the diffraction with or
without the telescope. You will get brighter lines with the telescope,
but the wavelengths measured will be no different, and this tells you
that the wavelength doesn't have anything to do with the telescope.

That's why the grating measures a new wavelength for it.
If it is sodium then the grating would have measure a wavelength of
588.995 nm.

And that is simply NOT true. As I've told you at least 20 times, the
identification as sodium has to do with the *ratio* of several
wavelengths. It has NOTHING to do with seeing a wavelength of 588.995
nm. A source can easily be identified as sodium even though there is
NO line centered at 588.995 nm, and in fact this is how spectroscopy
is done.

You are under the mistaken impression that sodium sources always have
a line at 588.995 nm, but you don't have the foggiest idea how
spectroscopy is done, what equipment is required to make the
measurement, or even what causes the emission spectrum in the first
place. Does it not occur to you that you might be mistaken that sodium
always has a line centered on 588.995 nm?


Sorry, Ken, valid reasoning does not trump measurement in science.
Never has, never will. If you have valid reasoning that says something
other than what measurement says, then your valid reasoning is simply
wrong nevertheless.

Wavelength doen't change during transit. Light speed change due to
motion of the observer wrt the incoming light rays.

Repeating an error doesn't make it right. The wavelength is *measured*
to be different than 588.995 nm, so it IS different than 588.995 nm.

The incoming sodium light becomes a new light source in the frame of
the grating. This is true no matter how you scream and cry foul.


Sorry, Ken, you're making a statement from a basis of ignorance. You
don't know what causes an emission spectrum, you don't know how to
make or use a diffraction spectrometer, and you don't know how to
recognize sodium from a spectrum.



You cannot insist that it must nevertheless be 588.995 nm, just
because you don't understand how it could be different than 588.995
nm. The experiment tells you it IS different, and you see it with your
own eyes. At least, you do if you actually do the experiment.

It is a much better concept than to assume that the incoming sodium
light is arriving at a constant c. Such assumption require light to
change speed during transit to eliminate the effect of relative motion
between the source and the observer.


No, it is not a better concept to permit the changing of a measured
value to be something other than what was measured. That is a bad
idea.



Valid reasoning does not make good science. Valid reasoning and 75
cents will buy you a cup of coffee. Valid reasoning that also happens
to agree with measurement, on the other hand, is extremely valuable.
Changing measured values to conform with what you think is valid
reasoning is not only worthless, but it is scientific fraud.

I did not change any measured value. The grating defines a different
wavelength for different light ray passing through it. The incoming
sodium light is a different light ray in so far as the grating is
concerned.

No, it's not. It's the same light ray. There's absolutely nothing
between the source and the grating. The grating measures the
wavelength of the light ray DIRECTLY. It's your favorite kind of
measurement -- the direct one.

Yes there is something between the source and the grating....the
telescope that clooect the sodium light from the source.

There is no telescope necessary. As I said, you've got no idea how to
build or run a diffraction spectrometer.


No, that observer does measure the light speed to be c relative to the
source. But that isn't what the other observer sees.

So what is the observer at the source frame measures the speed of his
light source to be?

On average, zero. Why?

??????are you saying that he doen't maeasure his own light to have a
speed of c????

That's not what you asked. You asked about the speed of the light
*source*, not the speed of the light from the source.

I said the speed of light in the source frame.

Ken, what you said is directly above. "So what is the observer at the
source frame measures the speed of his light source to be?" Don't be
an idiot.

PD

"kenseto" wrote in message
...
On Jan 3, 2:14 pm, PD wrote:
On Jan 3, 10:37 am, kenseto wrote:
So where is the wavelength of 588.995 nm for sodium come from?
It comes from putting a mark at the *center* of a distribution of
wavelengths that comprise a "line" from a *particular* sodium source,
one that is at rest relative to the observer.

Since sodium when heated has two *centers* of distributions of
wavelengths are you saying the both of these *centers* are generated
by sodium atoms at rest wrt the grating?

Yes

How is that possible?

You mean you really don't know .. oh dear .. this is sad.

[snip more stupid questions and even stupider assertions that are not even
worth addressing]