Some troubling assumptions of SR

In article ,
(Dan from Boston) wrote:

Have any of these guys who are continually 'refuting' SR and GR ever taken
any math courses past algebra and trig? their analyses are pitiable.

***{Mainly, we have been discussing whether the gravitationally
entrained aether theory can or cannot explain stellar aberration, and
everyone who has posted anything on the topic, whether pro or con, has
made use of no math beyond trigonometry, for the simple and sufficient
reason that trigonometry is the math which such an analysis requires.

The only attack on relativity that was posted in connection with that
discussion was posted by me, and I assume from your comment that you
disagree with it, since you characterized my analysis as "pitiable." So
let me ask you a question: if someone told you that (a) automobile
speeds are a universal constant the value of which is 50 mph, and (b)
that the speed of each automobile has to be measured using an onboard
clock that automatically registers 1 hour for every 50 miles traveled,
would you accept his conclusion?

If not, then why would you accept Einstein's statement that (a) the
speed of light is a universal constant the value of which is 186,000
miles/sec, and (b) that the speed of light has to be measured using a
clock in the vicinity of the lightpath which automatically registers 1
second for every 186,000 miles that light travels?

In other words, why can't we follow standard practice, and use clocks
calibrated to run at the same rate as standard time here on Earth?
That's what we do when we measure the speeds of automobiles and
everything else. Why must we make an exception for light?

Enquiring minds want to know! :-)

--Mitchell Jones}***

Dan

***{Note: this is a re-post to correct a typo in the original. Please
respond to this version. Thanks. --MJ}***

************************************************** ***************
If I seem to be ignoring you, consider the possibility
that you are in my killfile. --MJ

"Mitchell Jones" wrote in message
...
....
The only attack on relativity that was posted in connection with that
discussion was posted by me, and I assume from your comment that you
disagree with it, since you characterized my analysis as "pitiable." So
let me ask you a question: if someone told you that (a) automobile
speeds are a universal constant the value of which is 50 mph, and (b)
that the speed of each automobile has to be measured using an onboard
clock that automatically registers 1 hour for every 50 miles traveled,
would you accept his conclusion?

If not, then why would you accept Einstein's statement that (a) the
speed of light is a universal constant the value of which is 186,000
miles/sec, and (b) that the speed of light has to be measured using a
clock in the vicinity of the lightpath which automatically registers 1
second for every 186,000 miles that light travels?

In other words, why can't we follow standard practice, and use clocks
calibrated to run at the same rate as standard time here on Earth?
That's what we do when we measure the speeds of automobiles and
everything else. Why must we make an exception for light?

Enquiring minds want to know! :-)

Enquiring minds would look up the definition of a second

http://www.bipm.fr/en/si/si_brochure...-1/second.html

"The second is the duration of 9192631770 periods
of the radiation corresponding to the transition
between the two hyperfine levels of the ground
state of the caesium 133 atom.

At its 1997 meeting the CIPM affirmed that:

This definition refers to a caesium atom at rest
at a temperature of 0K."

This note was intended to make it clear that the
definition of the SI second is based on a caesium
atom unperturbed by black body radiation, that is,
in an environment whose thermodynamic temperature
is 0K. The frequencies of all primary frequency
standards should therefore be corrected for the
shift due to ambient radiation, as stated at the
meeting of the Consultative Committee for Time and
Frequency in 1999."

That definition is used for all clocks regardless of what
they are measuring and all clocks should be calibrated
accordingly.

George

On Mar 9, 4:30 am, "George Dishman" wrote:
On 9 Mar, 02:03, " wrote:





On Mar 7, 5:15 am, "George Dishman" wrote:
On 6 Mar, 05:47, " wrote:
On Mar 3, 7:41 am, "George Dishman" wrote:
wrote in oglegroups.com...
...
Lets try this. You are standing in the open with no wind. An
airplane passes by from left to right. If the airplane dropped a
cannon ball observers on the plane would see the ball drop straight
down, staying directly under the plane as it fell. The observer on
the ground would see the ball dropping from left to right. Following
its path back up leads to a point behind the current location of the
plane, where the plane was when it dropped the ball. This is
aberration. Just consider the airplane to be a stationary star and we
are on the earth moving in our orbit. Have the airplane fly back in
the opposit direction (we have continued our orbit under the
stationary star) and the aberration angle changes direction.

When the cannon ball was dropped a charge of black powder was lit off
with a bang, leaving a cloud of smoke in the stationary air at the
point where the ball was dropped. That is the point we will hear the
sound come from in our stationary air (dragged aether). The airplane
will have moved on in the time it took for the sound to reach us, so
the sound will come from behind the airplane, just like the cannon
ball. When the airplane flys back the other way the sound trails in
the opposite direction.

So far we agree.

If you want the star to be at rest in the aether of space just change
the airplane to a balloon floating back and forth in the jet streams.
It wont effect the final leg of the sound's passage to us in our
stationary air.

That's where we disagree. Rather than the jet stream, suppose
there is a uniform wind at all heights above 100m but the air
in that last 100m is still. There is a shear at that height.
Suppose someone on the balloon fires a gun to create a sound
wavefront.

The sound propagates vertically down through the air from
the balloon as seen by someone in the balloon and the
wavefront is always horizontal:

b
_|_
_|_
_|_
_|_
_|_
.... _|_ ....

From the point of view of someone on the ground, the ballon
and the sound waves are carried sideways by the wind but
the wavefronts remain horizontal. When the sound reaches
the shear, the balloon has drifte to 'b' from the point
where the gun was fired at 'g'

b g
_/_
_/_
_/_
_/_
_/_
.... _/_ ....

If there were a stationary observer at the bottom of the diagonal line
watching b drift by, where would he hear the sound come from, b or g ?

It appears to come from b because the direction is the
normal to the wavefronts. The same is true in the
completed diagram below so the aberration is the angle
xob rather than xog.


I would agree that an observer floating along just above the boundry
in another balloon would hear the gun shot from b, but I have serious
doubts about a stationary observer. The particles that are
transfering the sound have some additional horizontal momentum for him
due to the wind. You don't think that makes any difference?





After the shear, the sound continues vertically and the
ballon drifts on to 'x' which it reaches when the gunshot
is heard on the ground by observer 'o':

x b g
_/_
_/_
_/_
_/_
_/_
.... _/_ .... shear
_|_
_|_
______o______ ground

The aberration is quite different from an aircraft
in uniformly moving air.

As I said elsewhere it is easy to miss things when doing an analysis.
Let's take a closer look at a wave front crossing the shear line. The
whole wave front does not hit the shear line at the same instant.


* *
* *
* *
* *
'
----------------------------------------------

What happens when part of the front stops moving horizontal while the
part that hasn't reached the shear line continues to move left until
it also reaches the shear line?



* *
* *
* *
* *
-----------------------'----------------------


* *
* *
* *
* *
-----------------------'----------------------


* *
* *
* *
--------------------*---*---------------------
'

* *
* *
* *
--------------------*---*---------------------
'


* *
* *
----------------*---------*-------------------
* *
'


* *
* *
----------------*---------*-------------------
* *
'


* *
--------------*-----------*--------------
* *
* *
'


* *
--------------*-----------*--------------
* *
* *
'

------------*-------------*-------------------
* *
* *
* *
'

If you now plot where the center of the front is you get something
like this.


------------*-------\-----*-------------------
* \ *
* \ *
* \*
'\


Does the ground observer hear the sound come from the center of this
wave front?

Yes, we use the down wind origin of the wave to calculate where the
wave front will be, but that is not where the sound came from.

It is where it appears to come from. Try drawing circles
radiating out from the source.

I disagree. This is what the real world experiment with sound
demonstrates. When there is a cross wind between two stationary
observers they still hear the sound come from the direction of the
source, not the down wind center of the wave front.

I have yet to be convinced of that. What was the link
to your experimental evidence again?

I provided no link. I was speaking of first hand observations you can
make yourself. Surely you have been in open areas when the wind was
blowing. Have you ever heard come from down wind of a stationary
object?

I have never tried it with equipment capable of measuring
the angle accurately enough and I doubt you have either. If
you have your eyes open, your brain identifies the source
with a combination of what your hear and what you see. Try
it wearing a blindfold and pointing to the source using
sound alone, get a friend to put two stakes in the ground
marking the direction, then take the blindfold off. You
will need a high wind speed to get a measurable offset.

I never have even when the distance was the better part of a
mile and the wind strong.

The distance doesn't matter, the sin of the angle is v/c
where c is the speed of sound.

When you view a car going by 40 feet away the angle defined by the car
is much larger than it is when the car is 4000 feet away. If the car
blows its horn at 40 feet and the sound is shifted back a foot it
would still seem to come from the front of the car. The same angle at
4000 feet would shift the sound by 100 feet, or about 5 car lengths
behind the car.

Yes, whether it is one foot in 40 or 100 in 4000, the
angle subtended at the listener is the same and it is
that angle that you measure so the distance is of no
interest in deciding whther you can measure the effect
by ear or if you need instrumentation. I don't believe
you could tell by ear without a very high wind speed.

We were discussing what we have observed in real life, not what you
would measure in some theoretical experiment. You yourself wrote
above, "If you have your eyes open, your brain identifies the source
with a combination of what your hear and what you see." When a car
goes by at 30 mph that is 44 feet per second. At 40 feet with sound
traveling at 1100 fps the car will have traveled 1.6 feet. If the car
blows its horn which is in the grill the sound will still seem to come
from under the hood of the car. That is a very close match with where
you would expect the sound to be coming from so the shift isn't
noticed. When a car 4000 feet away traveling at the same speed blows
its horn the sound lags 160 feet behind. That is about 10 car lengths
back. That is certainly far enough from the source to be noticed and
that is at just 30 mph. And yes, our ability to sense the direction
of a sound is quite accurate.





I have often heard the sound from an
airplane come from a point behind its current location, so I can
detect a difference in direction if one exists.

An aircraft travels at 600 mph, I doubt you have tried
the experiment blindfold is as much as 60 mph when you
would get 1/10th of the displacement.

I have easily detected the shift with an old prop driven plane flying
at ~100 mph. I can also detect it when cars drive by at ~60 mph if I
am 100 yards or more from the highway. When a jet is traveling at 600
mph the effect is so great that it sometimes takes a few seconds to
find the jet.

I have also
experienced traveling at high rates of speed near others at race
tracks.

So are you saying that you have experienced travelling
at 60 mph parallel to another driver also moving at the
same speed and can definitely say that when he shouted
to you from the other car his voice did not appear to
come from behind his car by 5 degrees? See the diagram
below. I want to see some independent proof of that
claim before I accept it.

At the drag strip I have traveled parallel to another car at up to 140
mph and never noticed any shift in the direction of sound. Of course
I may have been preoccupied, but I think I would have noticed.





To determine the direction the sound is coming from the receiver needs
at least two points.

Right. Try this sketch:

S

--- wind

|
A--+--B

A and B are microphones and S is a source, say a gun which
emits a single spherical wavefront, or you can use a tone
generator and measure phase difference.

We are trying to duplicate a wave traveling in the aether. The
signals in the wires travel faster than the sound waves so you are in
effect using faster than light communication to determine the timing
of the reception at A and B.

But in a dragged aether, both the aether at ground level
and the cables are at rest relative to the ground (which
is how dragged aether explains the MMX) therefore the
speed of the signals in the cables is equal. As long as
the cables are the same length, there is no time
difference introduced, the actual speed is irrelevant.

snip as you did not comment

.. How can blocking the
line of sight path effect the path from down wind?

Because the sound is actually coming from the object which
hasn't moved but the wavefronts lie at an angle to the line
of sight like a swimmer crossing a river, he has to face
slightly upstream in order to swim perpendicular to the bank.

When that swimmer reaches you, after leaving the bank at a point
straight across, do you claim that he swam up from some point down
stream because that is where the water is that he swam through?

No, all I claim is that he is at the same angle to the
bank as he would have been had he swum from some point
downstream if the water was at rest. All we can measure
is the apparent source of the starlight.

George

So we can agree that his path was straight across.

Bruce

Mitchell Jones wrote:

If not, then why would you accept Einstein's statement that (a) the
speed of light is a universal constant the value of which is 186,000
miles/sec, and

Actually, as written, he proposed it as a postulate and ran with that
to derive what the implications would be. Turns out that none of the
implications have ever been refuted by experiment.

(b) that the speed of light has to be measured using a
clock in the vicinity of the lightpath which automatically registers 1
hour for every 186,000 miles that light travels?

Can you produce an actual quotation from the 1905 paper that supports
this statement of yours?


Bob
--

"Things should be described as simply as possible, but no simpler."

A. Einstein

wrote in message
ups.com...
On Mar 9, 4:30 am, "George Dishman" wrote:
On 9 Mar, 02:03, " wrote:
On Mar 7, 5:15 am, "George Dishman" wrote:
On 6 Mar, 05:47, " wrote:
On Mar 3, 7:41 am, "George Dishman"
wrote:
wrote in
oglegroups.com...
...
Lets try this. You are standing in the open with no wind. An
airplane passes by from left to right. If the airplane dropped a
cannon ball observers on the plane would see the ball drop straight
down, staying directly under the plane as it fell. The observer on
the ground would see the ball dropping from left to right.
Following
its path back up leads to a point behind the current location of
the
plane, where the plane was when it dropped the ball. This is
aberration. Just consider the airplane to be a stationary star and
we
are on the earth moving in our orbit. Have the airplane fly back
in
the opposit direction (we have continued our orbit under the
stationary star) and the aberration angle changes direction.

When the cannon ball was dropped a charge of black powder was lit
off
with a bang, leaving a cloud of smoke in the stationary air at the
point where the ball was dropped. That is the point we will hear
the
sound come from in our stationary air (dragged aether). The
airplane
will have moved on in the time it took for the sound to reach us,
so
the sound will come from behind the airplane, just like the cannon
ball. When the airplane flys back the other way the sound trails
in
the opposite direction.

So far we agree.

If you want the star to be at rest in the aether of space just
change
the airplane to a balloon floating back and forth in the jet
streams.
It wont effect the final leg of the sound's passage to us in our
stationary air.

That's where we disagree. Rather than the jet stream, suppose
there is a uniform wind at all heights above 100m but the air
in that last 100m is still. There is a shear at that height.
Suppose someone on the balloon fires a gun to create a sound
wavefront.

The sound propagates vertically down through the air from
the balloon as seen by someone in the balloon and the
wavefront is always horizontal:

b
_|_
_|_
_|_
_|_
_|_
.... _|_ ....

From the point of view of someone on the ground, the ballon
and the sound waves are carried sideways by the wind but
the wavefronts remain horizontal. When the sound reaches
the shear, the balloon has drifte to 'b' from the point
where the gun was fired at 'g'

b g
_/_
_/_
_/_
_/_
_/_
.... _/_ ....

If there were a stationary observer at the bottom of the diagonal line
watching b drift by, where would he hear the sound come from, b or g ?

It appears to come from b because the direction is the
normal to the wavefronts. The same is true in the
completed diagram below so the aberration is the angle
xob rather than xog.


I would agree that an observer floating along just above the boundry
in another balloon would hear the gun shot from b, but I have serious
doubts about a stationary observer. The particles that are
transfering the sound have some additional horizontal momentum for him
due to the wind. You don't think that makes any difference?





After the shear, the sound continues vertically and the
ballon drifts on to 'x' which it reaches when the gunshot
is heard on the ground by observer 'o':

x b g
_/_
_/_
_/_
_/_
_/_
.... _/_ .... shear
_|_
_|_
______o______ ground

The aberration is quite different from an aircraft
in uniformly moving air.

As I said elsewhere it is easy to miss things when doing an analysis.
Let's take a closer look at a wave front crossing the shear line. The
whole wave front does not hit the shear line at the same instant.


* *
* *
* *
* *
'
----------------------------------------------

What happens when part of the front stops moving horizontal while the
part that hasn't reached the shear line continues to move left until
it also reaches the shear line?



* *
* *
* *
* *
-----------------------'----------------------


* *
* *
* *
* *
-----------------------'----------------------


* *
* *
* *
--------------------*---*---------------------
'

* *
* *
* *
--------------------*---*---------------------
'


* *
* *
----------------*---------*-------------------
* *
'


* *
* *
----------------*---------*-------------------
* *
'


* *
--------------*-----------*--------------
* *
* *
'


* *
--------------*-----------*--------------
* *
* *
'

------------*-------------*-------------------
* *
* *
* *
'

If you now plot where the center of the front is you get something
like this.


------------*-------\-----*-------------------
* \ *
* \ *
* \*
'\


Does the ground observer hear the sound come from the center of this
wave front?

No, he hears it arrive from a direction perpendicular to the
surface of the wavefront when it reaches him. That makes it
a bit more complex and the easiest way to explain the effect
may be to consider where someone needs to stand to hear the
sound directly above them. When the wave you show first
reaches the ground, the observer shown hears the source
directly above.

* *
* *
----------------*---------*-------------------
* *
________'________

I've skipped your intermediate diagrams and I think the second
was one character out. The ' in this is half way between the
two points where the wavefront reaches the ground and would be
where the next wavefront touches down:


* *
--------------*-----------*--------------
* *
____*__'__*______


And here's the next.



------------*-------------*-------------------
* *
_*____'____*_____


Bear in mind the source is moving from right to left so the
observer only sees it directly above at one particular time.
In other words proper motion of the star would still be
detectable but there is no aberration. It is like the plane
overhead, the sound appears to come from behind but it also
moves at the same speed as the plane. With the dragged aether
and shear, the sound appears to come from the plane and still
moves with the plane. Of course the plane would fall out of
the sky if this actually happened, no air speed, but you
should be able to follow what I mean.

Yes, we use the down wind origin of the wave to calculate
where the
wave front will be, but that is not where the sound came
from.

It is where it appears to come from. Try drawing circles
radiating out from the source.

I disagree. This is what the real world experiment with sound
demonstrates. When there is a cross wind between two
stationary
observers they still hear the sound come from the direction of
the
source, not the down wind center of the wave front.

I have yet to be convinced of that. What was the link
to your experimental evidence again?

I provided no link. I was speaking of first hand observations you
can
make yourself. Surely you have been in open areas when the wind
was
blowing. Have you ever heard come from down wind of a stationary
object?

I have never tried it with equipment capable of measuring
the angle accurately enough and I doubt you have either. If
you have your eyes open, your brain identifies the source
with a combination of what your hear and what you see. Try
it wearing a blindfold and pointing to the source using
sound alone, get a friend to put two stakes in the ground
marking the direction, then take the blindfold off. You
will need a high wind speed to get a measurable offset.

I never have even when the distance was the better part of a
mile and the wind strong.

The distance doesn't matter, the sin of the angle is v/c
where c is the speed of sound.

When you view a car going by 40 feet away the angle defined by the car
is much larger than it is when the car is 4000 feet away. If the car
blows its horn at 40 feet and the sound is shifted back a foot it
would still seem to come from the front of the car. The same angle at
4000 feet would shift the sound by 100 feet, or about 5 car lengths
behind the car.

Yes, whether it is one foot in 40 or 100 in 4000, the
angle subtended at the listener is the same and it is
that angle that you measure so the distance is of no
interest in deciding whther you can measure the effect
by ear or if you need instrumentation. I don't believe
you could tell by ear without a very high wind speed.

We were discussing what we have observed in real life, not what you
would measure in some theoretical experiment. You yourself wrote
above, "If you have your eyes open, your brain identifies the source
with a combination of what your hear and what you see." When a car
goes by at 30 mph that is 44 feet per second. At 40 feet with sound
traveling at 1100 fps the car will have traveled 1.6 feet. If the car
blows its horn which is in the grill the sound will still seem to come
from under the hood of the car. That is a very close match with where
you would expect the sound to be coming from so the shift isn't
noticed. When a car 4000 feet away traveling at the same speed blows
its horn the sound lags 160 feet behind. That is about 10 car lengths
back. That is certainly far enough from the source to be noticed and
that is at just 30 mph. And yes, our ability to sense the direction
of a sound is quite accurate.

What you wrote above was this:

... This is what the real world experiment with sound
demonstrates. When there is a cross wind between two
stationary
observers they still hear the sound come from the direction of
the
source, not the down wind center of the wave front.

We were talking about "two stationary observers", not a
moving car.


I have also
experienced traveling at high rates of speed near others at race
tracks.

So are you saying that you have experienced travelling
at 60 mph parallel to another driver also moving at the
same speed and can definitely say that when he shouted
to you from the other car his voice did not appear to
come from behind his car by 5 degrees? See the diagram
below. I want to see some independent proof of that
claim before I accept it.

At the drag strip I have traveled parallel to another car at up to 140
mph and never noticed any shift in the direction of sound. Of course
I may have been preoccupied, but I think I would have noticed.

I think it may be quite difficult to locate the exact source
of the sound in that case. How far were you from the other
car?

....
When that swimmer reaches you, after leaving the bank at a point
straight across, do you claim that he swam up from some point down
stream because that is where the water is that he swam through?

No, all I claim is that he is at the same angle to the
bank as he would have been had he swum from some point
downstream if the water was at rest. All we can measure
is the apparent source of the starlight.

So we can agree that his path was straight across.

And we can agree he arrived at an angle. Neither of
those seem particularly relevant though.

George

On Mar 12, 5:08 pm, Lester Zick wrote:
On Mon, 12 Mar 2007 12:58:35 -0400, Bob Kolker
wrote:

Lester Zick wrote:

Also turns out that the one assumption of geometric contraction
required to support that postulate has ever been supported by
experiment either.

Neither here nor there. The only thing that count are the predictions.
Are they right (empirically) or are they wrong (empirically). Science is
about making correct predictions.

So, Bob, you're telling me that science is about fortune telling? I
don't think so. Empiricism is about fortune telling but science is a
trifle more analytical than that. Science has to tell us why one thing
is true and another not.

It doesn't really do a good job of that. Every scientific theory to
date is an "effective" theory in the sense that there are certain
things that are incorporated in the theory because they appear to be
true, but not that they HAVE to be true at the exclusion of all other
possibilities. In the course of finding a deeper theory, one sometimes
finds that the reasons those things are true are that they are implied
by other, more fundamental things that appear to be true (but do not
HAVE to be true at the exclusion of all other possibities). To date,
there is not a SINGLE scientific theory that has no empirically
derived statements, and which as a whole MUST be true. You are welcome
to try to find that "ultimate" theory, but again the figure of merit
is not what you think science should be doing, but is instead
*usefulness*.

Einstein's postulate of a constant relative
velocity of light is a very interesting prediction.

It's not a prediction. It's an assumption, from which other
predictions are made. That's why Einstein called it a *postulate*, not
a theoretical prediction.

PD

Unfortunately the
second order velocity dependent geometric anisometry on which it rests
cannot be independently verified as a prediction. On the other hand
the trifling prediction on which the success of Michelson-Morley rests
is eminently capable of independent experimental verification which
will deny the assumption on which Einstein's postulate rests.

On Mar 12, 5:18 pm, "PD" wrote:
On Mar 12, 5:08 pm, Lester Zick wrote:





On Mon, 12 Mar 2007 12:58:35 -0400, Bob Kolker
wrote:

Lester Zick wrote:

Also turns out that the one assumption of geometric contraction
required to support that postulate has ever been supported by
experiment either.

Neither here nor there. The only thing that count are the predictions.
Are they right (empirically) or are they wrong (empirically). Science is
about making correct predictions.

So, Bob, you're telling me that science is about fortune telling? I
don't think so. Empiricism is about fortune telling but science is a
trifle more analytical than that. Science has to tell us why one thing
is true and another not.

It doesn't really do a good job of that. Every scientific theory to
date is an "effective" theory in the sense that there are certain
things that are incorporated in the theory because they appear to be
true, but not that they HAVE to be true at the exclusion of all other
possibilities. In the course of finding a deeper theory, one sometimes
finds that the reasons those things are true are that they are implied
by other, more fundamental things that appear to be true (but do not
HAVE to be true at the exclusion of all other possibities). To date,
there is not a SINGLE scientific theory that has no empirically
derived statements, and which as a whole MUST be true. You are welcome
to try to find that "ultimate" theory, but again the figure of merit
is not what you think science should be doing, but is instead
*usefulness*.

Einstein's postulate of a constant relative
velocity of light is a very interesting prediction.

It's not a prediction. It's an assumption, from which other
predictions are made. That's why Einstein called it a *postulate*, not
a theoretical prediction.

PD

Actually as Einstein says in "Relativity" it is not an assumption, it
is a stipulation. Everything is derived based on that fact. If you
use the speed of light to measure a distance, and then use that
distance to measure the speed of light, you had better come up with
the speed you started with

Bruce




Unfortunately the
second order velocity dependent geometric anisometry on which it rests
cannot be independently verified as a prediction. On the other hand
the trifling prediction on which the success of Michelson-Morley rests
is eminently capable of independent experimental verification which
will deny the assumption on which Einstein's postulate rests.- Hide quoted text -

- Show quoted text -- Hide quoted text -

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On Mar 12, 1:54 pm, "George Dishman" wrote:
wrote in message

ups.com...

On Mar 9, 4:30 am, "George Dishman" wrote:
On 9 Mar, 02:03, " wrote:
On Mar 7, 5:15 am, "George Dishman" wrote:
On 6 Mar, 05:47, " wrote:
On Mar 3, 7:41 am, "George Dishman"
wrote:
wrote in
oglegroups.com...
...
Lets try this. You are standing in the open with no wind. An
airplane passes by from left to right. If the airplane dropped a
cannon ball observers on the plane would see the ball drop straight
down, staying directly under the plane as it fell. The observer on
the ground would see the ball dropping from left to right.
Following
its path back up leads to a point behind the current location of
the
plane, where the plane was when it dropped the ball. This is
aberration. Just consider the airplane to be a stationary star and
we
are on the earth moving in our orbit. Have the airplane fly back
in
the opposit direction (we have continued our orbit under the
stationary star) and the aberration angle changes direction.

When the cannon ball was dropped a charge of black powder was lit
off
with a bang, leaving a cloud of smoke in the stationary air at the
point where the ball was dropped. That is the point we will hear
the
sound come from in our stationary air (dragged aether). The
airplane
will have moved on in the time it took for the sound to reach us,
so
the sound will come from behind the airplane, just like the cannon
ball. When the airplane flys back the other way the sound trails
in
the opposite direction.

So far we agree.

If you want the star to be at rest in the aether of space just
change
the airplane to a balloon floating back and forth in the jet
streams.
It wont effect the final leg of the sound's passage to us in our
stationary air.

That's where we disagree. Rather than the jet stream, suppose
there is a uniform wind at all heights above 100m but the air
in that last 100m is still. There is a shear at that height.
Suppose someone on the balloon fires a gun to create a sound
wavefront.

The sound propagates vertically down through the air from
the balloon as seen by someone in the balloon and the
wavefront is always horizontal:

b
_|_
_|_
_|_
_|_
_|_
.... _|_ ....

From the point of view of someone on the ground, the ballon
and the sound waves are carried sideways by the wind but
the wavefronts remain horizontal. When the sound reaches
the shear, the balloon has drifte to 'b' from the point
where the gun was fired at 'g'

b g
_/_
_/_
_/_
_/_
_/_
.... _/_ ....

If there were a stationary observer at the bottom of the diagonal line
watching b drift by, where would he hear the sound come from, b or g ?

It appears to come from b because the direction is the
normal to the wavefronts. The same is true in the
completed diagram below so the aberration is the angle
xob rather than xog.

I would agree that an observer floating along just above the boundry
in another balloon would hear the gun shot from b, but I have serious
doubts about a stationary observer. The particles that are
transfering the sound have some additional horizontal momentum for him
due to the wind. You don't think that makes any difference?

After the shear, the sound continues vertically and the
ballon drifts on to 'x' which it reaches when the gunshot
is heard on the ground by observer 'o':

x b g
_/_
_/_
_/_
_/_
_/_
.... _/_ .... shear
_|_
_|_
______o______ ground

The aberration is quite different from an aircraft
in uniformly moving air.

As I said elsewhere it is easy to miss things when doing an analysis.
Let's take a closer look at a wave front crossing the shear line. The
whole wave front does not hit the shear line at the same instant.

* *
* *
* *
* *
'
----------------------------------------------

What happens when part of the front stops moving horizontal while the
part that hasn't reached the shear line continues to move left until
it also reaches the shear line?

* *
* *
* *
* *
-----------------------'----------------------

* *
* *
* *
* *
-----------------------'----------------------

* *
* *
* *
--------------------*---*---------------------
'

* *
* *
* *
--------------------*---*---------------------
'

* *
* *
----------------*---------*-------------------
* *
'

* *
* *
----------------*---------*-------------------
* *
'

* *
--------------*-----------*--------------
* *
* *
'

* *
--------------*-----------*--------------
* *
* *
'

------------*-------------*-------------------
* *
* *
* *
'

If you now plot where the center of the front is you get something
like this.

------------*-------\-----*-------------------
* \ *
* \ *
* \*
'\

Does the ground observer hear the sound come from the center of this
wave front?

No, he hears it arrive from a direction perpendicular to the
surface of the wavefront when it reaches him. That makes it
a bit more complex and the easiest way to explain the effect
may be to consider where someone needs to stand to hear the
sound directly above them. When the wave you show first
reaches the ground, the observer shown hears the source
directly above.

* *
* *
----------------*---------*-------------------
* *
________'________

I've skipped your intermediate diagrams and I think the second
was one character out. The ' in this is half way between the
two points where the wavefront reaches the ground and would be
where the next wavefront touches down:

No, the ' was off center in the second diagram on purpose. The ' is
on the vertical axis of the original wave front. When it hits the
stationary air it stops moving to the left. That is what you have
claimed happens. The rest of the wave is still up above the shear
line, so it keeps moving. By the time the * on either side of the '
have moved down to the shear line they have moved over one space, so
the ' is no longer centered between them. In the next view they stay
stationary while the wave above the shear line continues to move
over. In the end you get this.

------------*-------\-----*-------------------
* \ *
* \ *
* \*
'\

Draw a smooth curve through the points and you have the shape of the
wave after it passes through the shear line. It is no longer
circular. If you want the line through ' that is normal to the curve
it would be the line perpendicular to the tangent at that point.
Since the curve has a smaller radius to the right of ' than to the
left, the tangent will not be horizontal and the normal will not be
vertical.

Yes, this is a crude ascii drawing and I did not allow for the fact
that the wave continues to expand horizontally as it expands
vertically, but I don't think there can be any disagreement that the
wave front is no longer circular nor that the normal line is no longer
vertical.

* *
--------------*-----------*--------------
* *
____*__'__*______

And here's the next.



------------*-------------*-------------------
* *
_*____'____*_____

Bear in mind the source is moving from right to left so the
observer only sees it directly above at one particular time.
In other words proper motion of the star would still be
detectable but there is no aberration. It is like the plane
overhead, the sound appears to come from behind but it also
moves at the same speed as the plane. With the dragged aether
and shear, the sound appears to come from the plane and still
moves with the plane. Of course the plane would fall out of
the sky if this actually happened, no air speed, but you
should be able to follow what I mean.

That's why we were using a floating balloon ;-)

Yes, we use the down wind origin of the wave to calculate
where the
wave front will be, but that is not where the sound came
from.

It is where it appears to come from. Try drawing circles
radiating out from the source.

I disagree. This is what the real world experiment with sound
demonstrates. When there is a cross wind between two
stationary
observers they still hear the sound come from the direction of
the
source, not the down wind center of the wave front.

I have yet to be convinced of that. What was the link
to your experimental evidence again?

I provided no link. I was speaking of first hand observations you
can
make yourself. Surely you have been in open areas when the wind
was
blowing. Have you ever heard come from down wind of a stationary
object?

I have never tried it with equipment capable of measuring
the angle accurately enough and I doubt you have either. If
you have your eyes open, your brain identifies the source
with a combination of what your hear and what you see. Try
it wearing a blindfold and pointing to the source using
sound alone, get a friend to put two stakes in the ground
marking the direction, then take the blindfold off. You
will need a high wind speed to get a measurable offset.

I never have even when the distance was the better part of a
mile and the wind strong.

The distance doesn't matter, the sin of the angle is v/c
where c is the speed of sound.

When you view a car going by 40 feet away the angle defined by the car
is much larger than it is when the car is 4000 feet away. If the car
blows its horn at 40 feet and the sound is shifted back a foot it
would still seem to come from the front of the car. The same angle at
4000 feet would shift the sound by 100 feet, or about 5 car lengths
behind the car.

Yes, whether it is one foot in 40 or 100 in 4000, the
angle subtended at the listener is the same and it is
that angle that you measure so the distance is of no
interest in deciding whther you can measure the effect
by ear or if you need instrumentation. I don't believe
you could tell by ear without a very high wind speed.

We were discussing what we have observed in real life, not what you
would measure in some theoretical experiment. You yourself wrote
above, "If you have your eyes open, your brain identifies the source
with a combination of what your hear and what you see." When a car
goes by at 30 mph that is 44 feet per second. At 40 feet with sound
traveling at 1100 fps the car will have traveled 1.6 feet. If the car
blows its horn which is in the grill the sound will still seem to come
from under the hood of the car. That is a very close match with where
you would expect the sound to be coming from so the shift isn't
noticed. When a car 4000 feet away traveling at the same speed blows
its horn the sound lags 160 feet behind. That is about 10 car lengths
back. That is certainly far enough from the source to be noticed and
that is at just 30 mph. And yes, our ability to sense the direction
of a sound is quite accurate.

What you wrote above was this:

... This is what the real world experiment with sound
demonstrates. When there is a cross wind between two
stationary
observers they still hear the sound come from the direction of
the
source, not the down wind center of the wave front.

We were talking about "two stationary observers", not a
moving car.

The whole conversation is still there if you want to look back. The
moving car came up while dicussing if distance made any difference in
our perception of where a sound comes from or whether it was strictly
a matter of the angle.

I have also
experienced traveling at high rates of speed near others at race
tracks.

So are you saying that you have experienced travelling
at 60 mph parallel to another driver also moving at the
same speed and can definitely say that when he shouted
to you from the other car his voice did not appear to
come from behind his car by 5 degrees? See the diagram
below. I want to see some independent proof of that
claim before I accept it.

At the drag strip I have traveled parallel to another car at up to 140
mph and never noticed any shift in the direction of sound. Of course
I may have been preoccupied, but I think I would have noticed.

I think it may be quite difficult to locate the exact source
of the sound in that case. How far were you from the other
car?

Each car has a road the width of a two lane highway and there is a
guard rail between the two cars. I would guess between 30 and 40
feet. An open exhaust header by the door is a fairly easy source to
locate.


When that swimmer reaches you, after leaving the bank at a point
straight across, do you claim that he swam up from some point down
stream because that is where the water is that he swam through?

No, all I claim is that he is at the same angle to the
bank as he would have been had he swum from some point
downstream if the water was at rest. All we can measure
is the apparent source of the starlight.

So we can agree that his path was straight across.

And we can agree he arrived at an angle. Neither of
those seem particularly relevant though.

George

In article ,
"George Dishman" wrote:

"Mitchell Jones" wrote in message
...
...
The only attack on relativity that was posted in connection with that
discussion was posted by me, and I assume from your comment that you
disagree with it, since you characterized my analysis as "pitiable." So
let me ask you a question: if someone told you that (a) automobile
speeds are a universal constant the value of which is 50 mph, and (b)
that the speed of each automobile has to be measured using an onboard
clock that automatically registers 1 hour for every 50 miles traveled,
would you accept his conclusion?

If not, then why would you accept Einstein's statement that (a) the
speed of light is a universal constant the value of which is 186,000
miles/sec, and (b) that the speed of light has to be measured using a
clock in the vicinity of the lightpath which automatically registers 1
second for every 186,000 miles that light travels?

In other words, why can't we follow standard practice, and use clocks
calibrated to run at the same rate as standard time here on Earth?
That's what we do when we measure the speeds of automobiles and
everything else. Why must we make an exception for light?

Enquiring minds want to know! :-)

Enquiring minds would look up the definition of a second

http://www.bipm.fr/en/si/si_brochure...-1/second.html

"The second is the duration of 9192631770 periods
of the radiation corresponding to the transition
between the two hyperfine levels of the ground
state of the caesium 133 atom.

***{Enquiring minds would also note that nothing in the above specifies
the gravitational conditions to which the clock is subjected. They would
note further that, according to the equations of physics, all motions
are affected by the gravitational circumstances in the locality where
the clocks are operating. To be specific, as gravitational acceleration
increases, other things equal, clock rates slow down. The controlling
formula is the "gravitational time dilation equation," which is as
follows:

t = T[1 - 2gr/c^2]^.5

In the above, T is the duration of a time interval as measured by a
clock in deep space, where the acceleration due to gravity is trivially
small, and t is the same time interval as measured by an identical clock
subject to a gravitational acceleration of g at a distance r from a
center of mass. Examination of the formula will make it clear to you
that as g increases, other things equal, clocks slow down.

That includes clocks based on the behavior of the Cesium 133 atom.

Since the theory of relativity requires that we use "proper time" for
our measurements, and defines "proper time" as the time measured by a
clock in the same locality of the event being measured, that means we
must count off 9,192,631,770 transition cycles of a Cesium 133 atom IN
THE SAME LOCATION AS THE LIGHTPATH, when we measure out
a second. Note specifically that there is no way to calibrate a clock so
defined: if the Cesium 133 atom slows down in a high-g field, too bad.
We are required to count off 9,192,631,770 transition cycles and call it
a second, even if the Earth makes a complete circuit around its orbit
while the cesium atom in question is doing its thing--which could very
well be the case, if the value of g is high enough in the locality.

Suppose, for example, that g is high enough so that the local clock runs
half as fast as a clock on Earth that is using Central Standard Time.
Since the speed of light, as measured by the local clock--i.e., the
clock in the vicinity of the lightpath--is constant, and since the clock
in question is running half as fast as a clock on Earth using Central
Standard Time, it follows that the clock on Earth would count off 2
seconds while the clock near the lightpath counts off 1 second. And
since light will travel 186,000 miles in the interval in question, it
follows that if we use Central Standard Time to measure the interval,
the speed of light is 93,000 miles/sec!

Of course, the local clock only registered 1 second, and so if we rely
on it, we have to conclude that the speed of light is 186,000 miles/sec
at that location.

But, again, if we use Central Standard Time, or any other variant of
standard time used on Earth (Greenwich Mean Time, say), then the light
took 2 seconds to travel 186,000 miles, and we have to conclude that the
speed of light slowed by half in the high-g field. Result: we must
conclude that lightspeed is not a universal constant.

And you should note, George, that nothing whatsoever prevents us from
using standard time other than the idiot definition which ties the
second to a specific number of cesium atom transitions and Einstein's
requirement that we use "proper time." There is no way to calibrate a
cesium atom. It doesn't give a hoot how fast we want it to go. That
means we must count off 9,192,631,770 transition cycles of a cesium 133
atom near the lightpath, which will take twice as long as counting off
the same number of cycles of a cesium 133 atom on Earth.

The result of such procedures is to force the speed of light to be a
universal constant. We have adopted a "clock" that counts off a second
every time light travels 186,000 miles, because the local clock speeds
up or slows down in the exact same proportion as light speeds up or
slows down.

Of course, using such a "clock" is transparent nonsense. As I noted
yesterday, it is precisely as absurd as claiming that the speed of an
automobile is a universal constant, by requiring the use of local time
within the car, where an hour is counted off every time the odometer
advances by 50 miles.

I would add that it is easy to calibrate clocks so that they match
standard time, even if they are in a high-g field. To do that, we merely
use the so called "gravitational time dilation" formula, given above.
If, according to it, a clock at a particular location will tend to run
at half the rate of an identical clock on Earth, then we simply use an
onboard computer chip to double its readings before displaying them. And
if we want to talk about events in locations where computer chips and
clocks cannot exist, we simply reference standard time, measured by the
clocks where we live, which of course would be adjusted by the use of
such chips. This idea of using uncalibrated clocks at the location where
a phenomenon is occurring, or of imagining such clocks if we can't
actually go there, is simply insane.

--Mitchell Jones}***

At its 1997 meeting the CIPM affirmed that:

This definition refers to a caesium atom at rest
at a temperature of 0K."

This note was intended to make it clear that the
definition of the SI second is based on a caesium
atom unperturbed by black body radiation, that is,
in an environment whose thermodynamic temperature
is 0K. The frequencies of all primary frequency
standards should therefore be corrected for the
shift due to ambient radiation, as stated at the
meeting of the Consultative Committee for Time and
Frequency in 1999."

***{I repeat: the gravitational parameters are not specified. It should
be explicitly stated that all clocks are to be calibrated to match the
rates of clocks using standard time here on Earth, and it should be
explicitly stated that relativistic "proper time" is not to be used. But
no such requirements are set down. The result is exactly as I have
described: the speed of light becomes a universal constant, not because
laboratory measurement indicates it to be so, but in spite of the fact
that all laboratory measurements using standard time indicate that it is
not so.

Let me say it again: you cannot accept the so called "gravitational time
dilation" formula and use standard time, without concluding that the
speed of light varies depending on gravitational parameters, the most
important of which is g, the gravitational acceleration in the vicinity
of the lightpath. And, let me emphasize, the formula is derived from
laboratory measurements. It is a summary of peer-reviewed, generally
accepted experimental results, and it says that clocks in high-g fields
run slow, compared to clocks using standard time on Earth.

The only way to reach the conclusion that the speed of light is
constant, is to use clocks that speed up or slow down as light speeds
up or slows down. If clocks calibrated to display standard time are
used, one is forced inescapably to the conclusion that the speed of
light is a variable, not a constant. Using clocks that speed up or slow
down as the thing being measured speeds up or slows down, is a game for
morons. By means of it, any motion whatsoever can be turned into a
"universal constant."

Bottom line: if we use standard time, then according to all the relevant
experimental results and to the equations based on those results, the
speed of light is not a constant.

--Mitchell Jones}***

That definition is used for all clocks regardless of what
they are measuring and all clocks should be calibrated
accordingly.

***{You can't calibrate a cesium 133 atom, George. And all the relevant
experimental results and the equations based on those results, indicate
that a cesium 133 atom, and every other conventional physical process,
runs slower in a high-g field than it does in a low-g field, other
things equal. Thus if we use the definition of "second" that you quoted,
and reference motions to Einstein's "proper time"--i.e., if we use local
clocks--then we are not using standard time for our measurements. That
means we are using uncalibrated clocks, and our results are a joke, not
science. --MJ}***

George

************************************************** ***************
If I seem to be ignoring you, consider the possibility
that you are in my killfile. --MJ

On Mar 12, 10:03 pm, "
wrote:
On Mar 12, 5:18 pm, "PD" wrote:





On Mar 12, 5:08 pm, Lester Zick wrote:

On Mon, 12 Mar 2007 12:58:35 -0400, Bob Kolker
wrote:

Lester Zick wrote:

Also turns out that the one assumption of geometric contraction
required to support that postulate has ever been supported by
experiment either.

Neither here nor there. The only thing that count are the predictions.
Are they right (empirically) or are they wrong (empirically). Science is
about making correct predictions.

So, Bob, you're telling me that science is about fortune telling? I
don't think so. Empiricism is about fortune telling but science is a
trifle more analytical than that. Science has to tell us why one thing
is true and another not.

It doesn't really do a good job of that. Every scientific theory to
date is an "effective" theory in the sense that there are certain
things that are incorporated in the theory because they appear to be
true, but not that they HAVE to be true at the exclusion of all other
possibilities. In the course of finding a deeper theory, one sometimes
finds that the reasons those things are true are that they are implied
by other, more fundamental things that appear to be true (but do not
HAVE to be true at the exclusion of all other possibities). To date,
there is not a SINGLE scientific theory that has no empirically
derived statements, and which as a whole MUST be true. You are welcome
to try to find that "ultimate" theory, but again the figure of merit
is not what you think science should be doing, but is instead
*usefulness*.

Einstein's postulate of a constant relative
velocity of light is a very interesting prediction.

It's not a prediction. It's an assumption, from which other
predictions are made. That's why Einstein called it a *postulate*, not
a theoretical prediction.

PD

Actually as Einstein says in "Relativity" it is not an assumption, it
is a stipulation. Everything is derived based on that fact.

Well, the word "fact" is what tends to confuse. The data in direct and
deliberate test of one-way measurement of the speed of light using two
spatially separated clocks, are indeed rare, and so this being a
"fact" as demonstrable measurement is not something that is usually
cited. [That being said, there are ample indirect tests that make no
relativistic assumptions, and in fact there are several cases of
measurements that serve well as verification of the one-way
measurement of the speed of light even if they aren't intended as
experiments explicitly designed to test relativity. As an example,
experiments tangent to the Advanced Photon Source routinely gate their
instruments in accordance with flight time from the (moving) photon
source.]

The "facts" are what are measured, and these are tests of
*implications* of this stipulation. When the implications are tested,
this lends credibility to the correctness of the stipulation, without
requiring a direct test of the stipulation itself.

If you
use the speed of light to measure a distance, and then use that
distance to measure the speed of light, you had better come up with
the speed you started with

Yes, of course, but note the long time between 1905 and 1983, the
latter being the date when distance was defined in terms of the speed
of light. In the interim were all the manifold measurements that
nailed down the correctness of the stipulation, which in turn
*permitted* the definition of distance in terms of the speed of light.

PD




Unfortunately the
second order velocity dependent geometric anisometry on which it rests
cannot be independently verified as a prediction. On the other hand
the trifling prediction on which the success of Michelson-Morley rests
is eminently capable of independent experimental verification which
will deny the assumption on which Einstein's postulate rests