Re: space time

On Tue, 22 Aug 2006 15:44:00 -0500, Dick <remdickhm@xxxxxxxxxxxxx>
wrote:

On 22 Aug 2006 08:25:38 -0700, "Dwib" <dwibdwib@xxxxxxxxx> wrote:

*** wrote:
Light-year is also strange because it is a limited measure. Only so
many kilometers in a earth-year, fewer but never more.

You are over-analyzing the definition of "light year"... nearly to the
point of comedy.

The definition "A light-year is the distance light travels in 1 year"
is an approximate definition... as you have correctly pointed out.

When confronted with the fact that a "year" changes with time, any
scientist worth their PhD will quickly switch from using light-years
(as a distance measurement) to mega-kilometers or some other
well-defined distance standard.

Dwib

If one doesn't recognize that gravity controls the radius of the orbit
thus the cycle distance, it is stable and would have been familiar to
a world used to using the sun for so many other events in their lives.
In early times it was worshipped, so not hard to believe it would be a
gold standard to compare earth orbital circumference with the distance
a light would travel in one earth orbit. The approximate speed of
186,000 miles/second also is relative to a fraction of the earth's
rotation. A second is a fraction of the time/distance of one period
of earth rotation at the equator.

Time measures seem to all come to standard measures of length ratios.
Clocks are standardized on energy entropy, uniform release of energy
counted and accumulated and displayed.


Has anyone yet pointed out that a "light year" is now defined as the
distance light travels in a vacuum in one "Julian year", where "Julian
year" is defined as 365.25 days and one day is defined as .....?

In other words, "light year" as used by astronomers is defined in
terms of the speed of light and the definition of the second and has
absolutely nothing at all to do with gravity and the orbit of the
earth.



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