This is a continuation of part of the thread:
"relativity of simultaneity - real or perceived?"

"Curious" wrote in message
oups.com...


Martin Hogbin wrote:

If you take it as a starting postulate that slowly transported
clocks remain synchronised you can then use them to measure
the one-way speed of light. This has been done experimentally
and the answer is that light is always measured to travel at c.
This becomes an experimentally verified fact.

Do you agree with that?

That being the case we are free to use a beam of light to
synchronise clocks in any inertial frame. For example imagine
two clocks 450,000 km apart. We could start one at 0 s and
at the same time send a pulse to the other clock. When it
received this pulse the other clock would start, but at 1.5 s
because we know light will take 1.5 s to travel 450,000 km.

Are you happy with the logic of this?

This is the SR method of synchronising clocks (sometimes
called E-synch in this newsgroup by the anti-Einstein brigade)
Note that practically it much faster and more convenient than
slow transport but gives exactly the same results. This is
confirmed by experiment (and SR theory).

If you do not like this then you are forced to say that slowly
transported clocks do not remain synchronised. You are
quite free to do that if you like. How much shall we say
they change by when moved, how about 1ns per metre
of movement, or would you prefer another figure? Anything
less than 3 ns per meter is possible - pick a value, no one
can prove you wrong.

So, is it E-synch or not for you?


You asked me to specifically ask for agreement
each issue to save time; I have done that but you have not
responded. Do I take it that you agree completely with
everything I have said so far?

I take it you are eager to move on. What to?

Martin Hogbin

Martin Hogbin wrote:
This is a continuation of part of the thread:
"relativity of simultaneity - real or perceived?"

"Curious" wrote in message
oups.com...


Martin Hogbin wrote:

If you take it as a starting postulate that slowly transported
clocks remain synchronised you can then use them to measure
the one-way speed of light. This has been done experimentally
and the answer is that light is always measured to travel at c.
This becomes an experimentally verified fact.

Do you agree with that?

That being the case we are free to use a beam of light to
synchronise clocks in any inertial frame. For example imagine
two clocks 450,000 km apart. We could start one at 0 s and
at the same time send a pulse to the other clock. When it
received this pulse the other clock would start, but at 1.5 s
because we know light will take 1.5 s to travel 450,000 km.

Are you happy with the logic of this?

This is the SR method of synchronising clocks (sometimes
called E-synch in this newsgroup by the anti-Einstein brigade)
Note that practically it much faster and more convenient than
slow transport but gives exactly the same results. This is
confirmed by experiment (and SR theory).

If you do not like this then you are forced to say that slowly
transported clocks do not remain synchronised. You are
quite free to do that if you like. How much shall we say
they change by when moved, how about 1ns per metre
of movement, or would you prefer another figure? Anything
less than 3 ns per meter is possible - pick a value, no one
can prove you wrong.

So, is it E-synch or not for you?


You asked me to specifically ask for agreement
each issue to save time; I have done that but you have not

I asked you to explicitly state points (rather than re-work through
from 1st principles)

Didn't mean for you to specifically ask agree/disagree on each issue -
just at the end.

responded. Do I take it that you agree completely with
everything I have said so far?

My response was "Fine... use light"

To me, the Fine means agreement and the 'use light' equates to use
E-synch


I take it you are eager to move on. What to?

Wherever you are going... rememeber that this discussion was started by
the bomb experiment, in which I wanted to know what times on the clocks
SR predicts for frame 2. You answered by going down this road. I know
the question, but not where you are headed.

Anthony Rose

"Martin Hogbin" wrote in message
...
| This is a continuation of part of the thread:
| "relativity of simultaneity - real or perceived?"
|
| "Curious" wrote in message
| oups.com...
|
|
| Martin Hogbin wrote:
|
| If you take it as a starting postulate that slowly transported
| clocks remain synchronised you can then use them to measure
| the one-way speed of light. This has been done experimentally
| and the answer is that light is always measured to travel at c.
| This becomes an experimentally verified fact.
|
| Do you agree with that?
|
| That being the case we are free to use a beam of light to
| synchronise clocks in any inertial frame. For example imagine
| two clocks 450,000 km apart. We could start one at 0 s and
| at the same time send a pulse to the other clock. When it
| received this pulse the other clock would start, but at 1.5 s
| because we know light will take 1.5 s to travel 450,000 km.
|
| Are you happy with the logic of this?
|
| This is the SR method of synchronising clocks (sometimes
| called E-synch in this newsgroup by the anti-Einstein brigade)
| Note that practically it much faster and more convenient than
| slow transport but gives exactly the same results. This is
| confirmed by experiment (and SR theory).
|

Sorry to but in there but does this experiment include moving slowly up and
down a gravity gradient ? so maybe this only applies to frames at the same
gradient position and comoving inertialy with reference to the reference
E-synch clock frame?

snip

--
*** rD Vacuum Energy = 4 pi duration+length ^3 perhaps
http://home.freeuk.com/paulps/
Maybe updates. The spuds, beans and onions are coming up nicely. Ooh
ah.{:-)

"Martin Hogbin" wrote in message
...
This is a continuation of part of the thread:
"relativity of simultaneity - real or perceived?"

"Curious" wrote in message
oups.com...


Martin Hogbin wrote:

If you take it as a starting postulate that slowly transported
clocks remain synchronised you can then use them to measure
the one-way speed of light. This has been done experimentally
and the answer is that light is always measured to travel at c.
This becomes an experimentally verified fact.

The one-way speed of light is not c if the distance of separation between
the two synchronized ((using slow clock transport method) clocks is measured
using a physical ruler instead of using a light second to measure length.
Why? Using light second to measure length is the same as defining the speed
of light equal to c as follows:
The definition for a meter=1/299,792,458 light-second
Therefore 1 light-second=299,792,458m
Therefore the speed of light is by definition =1 light-second/1 second
=
299,792,458m/1 second

Ken Seto

"kenseto" wrote in message .. .

"Martin Hogbin" wrote in message
...
This is a continuation of part of the thread:
"relativity of simultaneity - real or perceived?"

"Curious" wrote in message
oups.com...


Martin Hogbin wrote:

If you take it as a starting postulate that slowly transported
clocks remain synchronised you can then use them to measure
the one-way speed of light. This has been done experimentally
and the answer is that light is always measured to travel at c.
This becomes an experimentally verified fact.

The one-way speed of light is not c if the distance of separation between
the two synchronized ((using slow clock transport method) clocks is measured
using a physical ruler instead of using a light second to measure length.
Why?

Ha! the Seto-Why-Clause is back.
I love it :-)

Using light second to measure length is the same as defining the speed
of light equal to c as follows:
The definition for a meter=1/299,792,458 light-second
Therefore 1 light-second=299,792,458m
Therefore the speed of light is by definition =1 light-second/1 second
=
299,792,458m/1 second

Ken Seto

In sci.physics.relativity, Dirk Van de moortel

wrote
on Wed, 01 Jun 2005 14:35:35 GMT
:

"kenseto" wrote in message .. .

"Martin Hogbin" wrote in message
...
This is a continuation of part of the thread:
"relativity of simultaneity - real or perceived?"

"Curious" wrote in message
oups.com...


Martin Hogbin wrote:

If you take it as a starting postulate that slowly transported
clocks remain synchronised you can then use them to measure
the one-way speed of light. This has been done experimentally
and the answer is that light is always measured to travel at c.
This becomes an experimentally verified fact.

The one-way speed of light is not c if the distance of separation between
the two synchronized ((using slow clock transport method) clocks is measured
using a physical ruler instead of using a light second to measure length.
Why?

Ha! the Seto-Why-Clause is back.
I love it :-)

Does he have proof this time? :-P :-)


Using light second to measure length is the same as defining the speed
of light equal to c as follows:
The definition for a meter=1/299,792,458 light-second
Therefore 1 light-second=299,792,458m
Therefore the speed of light is by definition =1 light-second/1 second
=
299,792,458m/1 second

Ken Seto






--
#191,
It's still legal to go .sigless.

"Curious" wrote in message
oups.com...


Martin Hogbin wrote:
This is a continuation of part of the thread:
"relativity of simultaneity - real or perceived?"

"Curious" wrote in message
oups.com...


Martin Hogbin wrote:

If you take it as a starting postulate that slowly transported
clocks remain synchronised you can then use them to measure
the one-way speed of light. This has been done experimentally
and the answer is that light is always measured to travel at c.
This becomes an experimentally verified fact.

Do you agree with that?

That being the case we are free to use a beam of light to
synchronise clocks in any inertial frame. For example imagine
two clocks 450,000 km apart. We could start one at 0 s and
at the same time send a pulse to the other clock. When it
received this pulse the other clock would start, but at 1.5 s
because we know light will take 1.5 s to travel 450,000 km.

Are you happy with the logic of this?

This is the SR method of synchronising clocks (sometimes
called E-synch in this newsgroup by the anti-Einstein brigade)
Note that practically it much faster and more convenient than
slow transport but gives exactly the same results. This is
confirmed by experiment (and SR theory).

If you do not like this then you are forced to say that slowly
transported clocks do not remain synchronised. You are
quite free to do that if you like. How much shall we say
they change by when moved, how about 1ns per metre
of movement, or would you prefer another figure? Anything
less than 3 ns per meter is possible - pick a value, no one
can prove you wrong.

So, is it E-synch or not for you?


You asked me to specifically ask for agreement
each issue to save time; I have done that but you have not

I asked you to explicitly state points (rather than re-work through
from 1st principles)

Didn't mean for you to specifically ask agree/disagree on each issue -
just at the end.

I cannot stress too much how important the issues I am
discussing are in understanding relativity and possible
alternatives. Where I have asked direct questions at the
end of a section, it would be useful if you would simply
answer 'yes' if you agree with me. If you have any doubts
it is best to mention them at the time rather than to humour
me and continue.

I am not trying to use any tricks or sleight of hand. If you
suspect anything say so.

Wherever you are going... remember that this discussion was started by
the bomb experiment, in which I wanted to know what times on the clocks
SR predicts for frame 2. You answered by going down this road. I know
the question, but not where you are headed.

I thought we had done with your bomb experiment. We agreed
that:

[Curious]
"The bomb experiment demonstrates that SR/GR assume
and rely on time being non-absolute in order to preserve
the concept that the speed of light is constant".

This is pretty well what Einstein's train experiment showed.


I have been going through the justification for Einstein's
second postulate. I have made clear that it is a free choice
but I hope I have demonstrated firstly that we are forced to
make a choice of some kind and secondly that Einstein's
was a good one.

Do you agree?


Martin Hogbin

"*** rD" wrote in message ...

"Martin Hogbin" wrote in message
...
| This is a continuation of part of the thread:
| "relativity of simultaneity - real or perceived?"
|
| "Curious" wrote in message
| oups.com...
|

Sorry to but in there but does this experiment include moving slowly up and
down a gravity gradient ? so maybe this only applies to frames at the same
gradient position and comoving inertialy with reference to the reference
E-synch clock frame?

At the beginning of the thread I made it clear that I was talking
about inertial frames only. I have not bothered to repeat that
in every post.

Martin Hogbin

"kenseto" wrote in message .. .

"Martin Hogbin" wrote in message
...
This is a continuation of part of the thread:
"relativity of simultaneity - real or perceived?"

"Curious" wrote in message
oups.com...


Martin Hogbin wrote:

If you take it as a starting postulate that slowly transported
clocks remain synchronised you can then use them to measure
the one-way speed of light. This has been done experimentally
and the answer is that light is always measured to travel at c.
This becomes an experimentally verified fact.

The one-way speed of light is not c if the distance of separation between
the two synchronized ((using slow clock transport method) clocks is measured
using a physical ruler instead of using a light second to measure length.

Yes it is.

Martin Hogbin

"Martin Hogbin" wrote in message
...

"kenseto" wrote in message
.. .

"Martin Hogbin" wrote in message
...
This is a continuation of part of the thread:
"relativity of simultaneity - real or perceived?"

"Curious" wrote in message
oups.com...


Martin Hogbin wrote:

If you take it as a starting postulate that slowly transported
clocks remain synchronised you can then use them to measure
the one-way speed of light. This has been done experimentally
and the answer is that light is always measured to travel at c.
This becomes an experimentally verified fact.

The one-way speed of light is not c if the distance of separation
between
the two synchronized ((using slow clock transport method) clocks is
measured
using a physical ruler instead of using a light second to measure
length.

Yes it is.

No it isn't. They have experiments that tested the one-way isotropy. But
they refused to report the one-way values for these experiments. The reason
is that the one-way value using physical rod length to measure length is not
c.

Ken Seto