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A short Relativistic Enigma



 
 
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  #1  
Old May 6th 11, 12:36 AM posted to sci.physics.relativity,sci.physics,sci.math,sci.astro
Koobee Wublee
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Posts: 815
Default A short Relativistic Enigma

On May 3, 8:50 am, hippolyte Lapoyat wrote:

Most of the people know that Sir Eddington made a measurement of the
deflection of light by the sun in 1919. Very few people know that a
friend of him, walking on the sun made a measurement , with the same
light ray, from the same star, at the same minute. What is the value
of the light deflection his friend have found?


The photon deflection experiment must be performed with observations
of at least two stars, and the observations must be conducted in two
different time incidences. Only by comparing the relative positions
of the two stars in two such observations, the deflected angle can be
determined.

In Eddington’s case, the instances were observed at exactly 6 months
apart where the “night” side measurement is not subject to sun’s
deflection. By comparing the “day” side observation to the “night”
side observation (undistorted), Eddington was able to determine the
angle of deflection. However, he lacked accurate and precision
measuring equipment to perform such task. His observations were
bogus, but this is beside the point.

In your case, you don’t have such luxury of finding a known
undistorted observation. In every measurement, at least one of the
two stars will be deflected by the same amount. Thus, you cannot
determine the angle of photon deflection at all. shrug

  #2  
Old May 6th 11, 12:41 AM posted to sci.physics.relativity,sci.physics,sci.math,sci.astro
Koobee Wublee
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Posts: 815
Default A short Relativistic Enigma

On May 5, 4:36*pm, Koobee Wublee wrote:
On May 3, 8:50 am, hippolyte Lapoyat wrote:

Most of the people know that Sir Eddington made a measurement of the
deflection of light by the sun in 1919. Very few people know that a
friend of him, walking on the sun made *a measurement , with the same
light ray, from the same star, at the same minute. What is the value
of the light deflection his friend have found?


The photon deflection experiment must be performed with observations
of at least two stars, and the observations must be conducted in two
different time incidences. *Only by comparing the relative positions
of the two stars in two such observations, the deflected angle can be
determined.

In Eddington’s case, the instances were observed at exactly 6 months
apart where the “night” side measurement is not subject to sun’s
deflection. *By comparing the “day” side observation to the “night”
side observation (undistorted), Eddington was able to determine the
angle of deflection. *However, he lacked accurate and precision
measuring equipment to perform such task. *His observations were
bogus, but this is beside the point.

In your case, you don’t have such luxury of finding a known
undistorted observation. *In every measurement, at least one of the
two stars will be deflected by the same amount. *Thus, you cannot
determine the angle of photon deflection at all. *shrug


Well, if you take the advantage of the sun’s rotation, you can locate
a star which is not deflected. The situation occurs when the star,
you, and the center of the sun form into a straight line. By
comparing this non-deflected star with two other deflected ones, you
might be able to determine the angle of deflection after comparing to
at least one more observation. shrug
  #3  
Old May 6th 11, 03:05 AM posted to sci.physics.relativity,sci.physics,sci.math,sci.astro
1treePetrifiedForestLane
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Posts: 974
Default A short Relativistic Enigma

Y, I'm not replying to your ejaculation ...
nor is this a spermbank.

hypothetically, the regime diametrically opposite
of the sunfacing node (say, on the surface
of Eaaarth) would have some sort of conjugate effect
upon "rays" of light, even though that is nothing
but geometrical optics, not part of a theory
of light. I mean,
the air is too thin to beathe, out there in either direction,
but you can try it!
  #4  
Old May 6th 11, 08:48 AM posted to sci.physics.relativity,sci.physics,sci.math,sci.astro
hippolyte Lapoyat
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Posts: 3
Default A short Relativistic Enigma

I suggest to compare our thought experiment with the Shapiro
experiment
About the Shapiro effect, Wikipedia says:

In a near-static gravitational field of moderate strength (say, of
stars and planets, but not one of a black hole or close binary system
of neutron stars) the effect may be considered as a special case of
gravitational time dilation. The speed of light in meters per given
interval of "local time" (calculated by the metric tensor) is a
constant, however the travel time of any electromagnetic wave, or
signal, moving at 299,792,458 meters per "second" is affected by the
time dilation in regions of the space through which it travels. This
is because the coordinate time and locally calculated time diverge as
the gravitational field potential increases (by absolute value).

Shapiro effect is related to the time delay due to light traveling
around a single mass. However, we can imagine that the Shapiro
experiment is also used to study the light deflection. For the reasons
above, time dilation is the main factor for curving the light ray.

If you look at the web site “newton-einstein.com”, you will be
convinced that in such circumstances (low gravitation- limited time
dilation) SR and GR are merged into the Newton mechanics.
I am inclined to conclude that Eddington’s friend has found a angle of
light deflection compatible with the newtonnian calculus i.e: Half
the value supposed to be measured by Eddington.
  #5  
Old May 6th 11, 06:01 PM posted to sci.physics.relativity,sci.physics,sci.math,sci.astro
Koobee Wublee
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Posts: 815
Default A short Relativistic Enigma

On May 6, 12:48 am, hippolyte Lapoyat wrote:
On May 5, Koobee Wublee wrote:

The photon deflection experiment must be performed with observations
of at least two stars, and the observations must be conducted in two
different time incidences. Only by comparing the relative positions
of the two stars in two such observations, the deflected angle can be
determined.


In Eddington’s case, the instances were observed at exactly 6 months
apart where the “night” side measurement is not subject to sun’s
deflection. By comparing the “day” side observation to the “night”
side observation (undistorted), Eddington was able to determine the
angle of deflection. However, he lacked accurate and precision
measuring equipment to perform such task. His observations were
bogus, but this is beside the point.


In your case, you don’t have such luxury of finding a known
undistorted observation. In every measurement, at least one of the
two stars will be deflected by the same amount. Thus, you cannot
determine the angle of photon deflection at all. shrug


Well, if you take the advantage of the sun’s rotation, you can locate
a star which is not deflected. The situation occurs when the star,
you, and the center of the sun form into a straight line. By
comparing this non-deflected star with two other deflected ones, you
might be able to determine the angle of deflection after comparing to
at least one more observation. shrug


Shapiro effect is related to the time delay due to light traveling
around a single mass. However, we can imagine that the Shapiro
experiment is also used to study the light deflection. For the reasons
above, time dilation is the main factor for curving the light ray.


Gravitational delay should not be confused with gravitational
deflection. shrug

If you look at the web site “newton-einstein.com”, you will be
convinced that in such circumstances (low gravitation- limited time
dilation) SR and GR are merged into the Newton mechanics.


Under pre-electromagnetism Newtonian mechanics, light particles can be
deflected by the sun’s gravity with the following effects:

** The deflection will result in a slightly longer path for the light
particle.

** Gravity will also cause a light corpuscle to increase speed during
inbound but decrease speed during outbound.

Say each contributes to one nibble of gravitational delay. The total
expected gravitational delay in this model is just 1 nibble.

Under Maxwellian electromagnetism, light particles can be deflected by
the sun’s gravity as well where the Aether forms a gravitational lens
that deflects light just like a prism would but with the following
effects.

** The deflection will result in a slightly longer path for the light
particle.

** Gravity will also cause the propagation of light to slow down.

The total expected gravitational delay in this model is 2 nibbles.

Under the Schwarzschild metric under GR, a photon can be deflected
with the following effects:

** The deflection will result in a slightly longer path for the light
particle but with twice the Newtonian prediction. So we have 2
nibbles here.

** Gravitational time dilation will cause light to slow down. This
effect contributes to only 1 nibble.

Adding up to all these effects, one would expect the gravitational
delay under GR to be 3 nibbles.

What did Shapiro have? 2 nibbles of gravitational delay. Only
Maxwellian electromagnetism passes Shapiro. shrug
 




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