Observed Moving Rod Contraction

When a rod travels away from the observer, the image of the end of the rod
closest to him takes less time to reach him than the image of the front end
of the rod. Consequently it will appear to be shorter than it really is.
This shortening effect becomes more noticeable the faster the rod travels
and the longer it is.

The Observed distance (X) a moving body has traveled at time t is equal to:
X = tvc / (v+c), as compared to the Actual distance traveled which is tv.
Where t is the time at which the observation is made, v the velocity of the
object away
from the observer, and c is the speed of light.
See my paper "Frames of Reference", formula [2], at my website at:
http://www2.rideau.net/gaasbeek

Similarly, if the Actual length of the rod is equal to (S) it follows that
its Observed length
(S') is equal to:
S' = Sc / (v+c)

That is to say, the Observed rod will appear shorter than it Actually is by
a factor of:
c / (v+c).

Enjoy, Len.
.................................................. ........

Len Gaasenbeek wrote:
When a rod travels away from the observer, the image of the end of the rod
closest to him takes less time to reach him than the image of the front end
of the rod. Consequently it will appear to be shorter than it really is.

Sure. This is utterly unrelated to the "length contraction" of SR. For
instance, why didn't you mention the "length expansion" of a rod moving
toward you?


Tom Roberts

To Robert,

I fail to see how my Observed length contraction is "utterly unrelated" to
the Observed length contraction as advocated by Special Relativity,
especially since my explanation makes sense whereas SR's doesn't.

However you are correct in assuming that the Observed slow down of the
parameters of a moving body will appear to speed up when it is traveling
towards, instead of away from, the observer, since the factor c / (v+c)
remains the same for the Observed:
- distance traveled,
- velocity,
- Doppler frequency and
- aging rate of the body.

Since on the way back the velocity of the body is now minus (-) v, the
Observed conversion factor becomes c / (c - v), which is greater instead of
less than one.

In other words on the way back, the distance traveled, the velocity, the
Doppler frequency and the aging rate of the body are now Observed to be
GREATER than they Actually are.

As a result the Observed parameters of the moving body are once more back in
synch. with the observer's Actual ('real time') parameters when the body
arrives home, since they have returned to the 'stationary' reference frame
of the observer.

That is to say, Observed reality and Actual reality coincide once more and
'The Twins' are the same Actual age again.

Len.
.................................................. ..................

"Tom Roberts" wrote in message
. ..
Len Gaasenbeek wrote:
When a rod travels away from the observer, the image of the end of the
rod
closest to him takes less time to reach him than the image of the front
end
of the rod. Consequently it will appear to be shorter than it really
is.

Sure. This is utterly unrelated to the "length contraction" of SR. For
instance, why didn't you mention the "length expansion" of a rod moving
toward you?


Tom Roberts

Len Gaasenbeek wrote:
I fail to see how my Observed length contraction is "utterly unrelated" to
the Observed length contraction as advocated by Special Relativity,

Yes. Because you use a PUN on "observed", and fail to make the important
distinction between "measured wrt coordinates as in SR" and "observed
via propagating light rays".

In SR, and indeed in any sensible use of the words, to properly measure
the length of a moving rod one must arrange to mark both ends of the rod
SIMULTANEOUSLY in one's own frame, and then measure the distance between
those marks. If both ends are not marked SIMULTANEOUSLY, then it's clear
that the moving rod will have moved between the measurements of its two
endpoints, and the result cannot at all be claimed to be the length of
the moving rod measured in this frame.

That is what you do, because you use light propagating from the
endpoints to a fixed observer's eyeball.

My kids understood in Kindergarten that to measure the length
of something one must not move the ruler between noting the
values for its endpoints. Why can't you understand this?


especially since my explanation makes sense whereas SR's doesn't.

No, your "explanation" involves a horrible PUN, and does not correspond
to the usual notion of "length of the moving rod" at all.


Tom Roberts

To Tom,

When one observes a distant moving body, the best one can do is take
measurements of its photographic image and/or analyse its radiation or
movement. This is what I am proposing and what constitutes good physics.

To measure something 'in regard its coordinates as in special relativity' is
so much double talk. Nor 'can one arrange to mark both ends of the rod
simultaneously in one's own frame and then measure the distance between
those marks'. This not only is equally silly, but can't be done.

No observer can study an object more effectively than when he uses cognitive
means which travel at the speed of light towards him. That is why
astronomers use telescopes to study the cosmos.

Consequently the best they can do is study Observed Reality, even if it is
thousands of light years away and presents them with a picture of what
things used to look like thousands of years ago, BECAUSE NO ONE CAN DO
BETTER THAN THAT!

All the rest of what you are suggesting is just pie in the sky!
I don't like to say this, but you are a typical example of a cult member who
tries to convert his critics by preaching his religious jargon. This of
course has nothing to do with scientific debate.

"If you want to find out anything from the theoretical physicists about the
methods they use, I advise you to stick closely to one principle: Don't
listen to their words, fix your attention on their deeds."
Albert Einstein,
The World As I See It.

Len.
.................................................. ......
"Tom Roberts" wrote in message
. ..
Len Gaasenbeek wrote:
I fail to see how my Observed length contraction is "utterly unrelated"
to
the Observed length contraction as advocated by Special Relativity,

Yes. Because you use a PUN on "observed", and fail to make the important
distinction between "measured wrt coordinates as in SR" and "observed
via propagating light rays".

In SR, and indeed in any sensible use of the words, to properly measure
the length of a moving rod one must arrange to mark both ends of the rod
SIMULTANEOUSLY in one's own frame, and then measure the distance between
those marks. If both ends are not marked SIMULTANEOUSLY, then it's clear
that the moving rod will have moved between the measurements of its two
endpoints, and the result cannot at all be claimed to be the length of
the moving rod measured in this frame.

That is what you do, because you use light propagating from the
endpoints to a fixed observer's eyeball.

My kids understood in Kindergarten that to measure the length
of something one must not move the ruler between noting the
values for its endpoints. Why can't you understand this?


especially since my explanation makes sense whereas SR's doesn't.

No, your "explanation" involves a horrible PUN, and does not correspond
to the usual notion of "length of the moving rod" at all.


Tom Roberts

"Len Gaasenbeek" wrote in message
...
To Tom,

When one observes a distant moving body, the best one can do is take
measurements of its photographic image and/or analyse its radiation or
movement. This is what I am proposing and what constitutes good physics.

To measure something 'in regard its coordinates as in special relativity'
is
so much double talk. Nor 'can one arrange to mark both ends of the rod
simultaneously in one's own frame and then measure the distance between
those marks'. This not only is equally silly, but can't be done.

No observer can study an object more effectively than when he uses
cognitive
means which travel at the speed of light towards him. That is why
astronomers use telescopes to study the cosmos.

Consequently the best they can do is study Observed Reality, even if it is
thousands of light years away and presents them with a picture of what
things used to look like thousands of years ago, BECAUSE NO ONE CAN DO
BETTER THAN THAT!

All the rest of what you are suggesting is just pie in the sky!
I don't like to say this, but you are a typical example of a cult member
who
tries to convert his critics by preaching his religious jargon. This of
course has nothing to do with scientific debate.

"If you want to find out anything from the theoretical physicists about
the
methods they use, I advise you to stick closely to one principle: Don't
listen to their words, fix your attention on their deeds."
Albert Einstein,
The World As I See It.

Len.

Have a series of laser beams spaced half a centimeter apart, shining
perpendicular to the direction of the motion of the rod, with electronic
eyes on the other side, attached to separate clocks. Record time readouts
and readouts of the eyes. Find the maximum distance between breaks in the
laser beam at any one particular time. Round to the nearest centimeter.

The calculations used to derive SR assume perfect measurement of actual
length, regardless of how a real experimenter would have to measure things.
Also, true length could simply be calculated from the length measured in a
photographic image. SR always assumes compensation where necessarry, such
as in calculations for simultaneity (where the observer compensates for the
speed of light in determining when events took place).

You have to understand that for your described effects to be the length
contractions of SR, the effect you've described would have to be factored
into the derivation, which it isn't. And since your described effect can
also lead to length expansion, and actually leads to an observed *rotation*
as well, that should give you a clue that it is unrelated to length
contractions. The phenomenon you have described is well documented in
physics texts, as a separate phenomenon from SR. The formula for length
contraction in SR, BTW, is l*sqr(1-v^2/c^2), so the two things can't be the
same anyway.

It is also ridiculous to assume that the actual length of a moving rod
cannot, even in principle, be discovered.