Re: This is What Einstein Actually Did.


"Randy Poe" <poespam-trap@xxxxxxxxx> wrote in message
news:1152719474.154681.89080@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

kenseto wrote:
"Randy Poe" <poespam-trap@xxxxxxxxx> wrote in message
news:1152714628.812917.98040@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx


Second, when you are measuring a velocity of something,
you measure the time and distance separately.

Exactly. But c is not based such a procedure.

No? Please describe any measurement of c prior to 1983
and show me how it doesn't use independent measurements
of time and distance to determine c.

How is the speed of light measured?


http://hermes.physics.adelaide.edu.au/~dkoks/Faq/Relativity/SpeedOfLight/mea
sure_c.html
None of the procedures described in this link uses the method of
measuring
the time and distance (using a measuring tape) separately.

First, you are incorrect. The Fizeau and Foucault measurements
in the 19th century are done that way.

And their results show that the speed of light is not constant.

Second, to measure the speed of light to 8 or 9 significant digits,
you need to be able to measure time of flight and distance
to 8 or 9 significant digits.

You don't need to measure light speed to 8 or 9 significant digits. You need
to perform experiments that give consistent results. As far as I can see
these older experiments using the direct method as specified by Einstein did
not give consistent results. So the claim of constancy of the speed of light
using the direct method has not been confirmed.

Ken Seto

A tape measure is good to maybe 3. That is why the Fizeau
and Foucault measurements are so inaccurate. Michelson
used the same method with more accurate distance and
time measurements to get to nearly 4 figures (he was off
by about 100 km/sec out of 300000). See this link:
http://micro.magnet.fsu.edu/primer/lightandcolor/speedoflight.html
Look for the description of an experiment along the Severn
River in Maryland.

It's still: Measure time, measure distance, divide distance
by time.

Michelson's interferometry allows much more precise
distance measurements, over smaller distances. I'm trying
to find a link to explain exactly how that is used to get
precise measurements of c.

- Randy



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