Re: space time

*** wrote:
So how far does light travel while the earth rotates one earth-sun
period?

1 light-year, no time needed.

Now is where things get strange. We may conceive of ways for the
earth-sun period to be changed

That is an issue of standards and not physics.

Wasn't there an English king defined a "yard" as the distance from his
nose to his outstreched fingertip? That's fine for that moment but
what happens when a new king/queen comes to power?

Likewise, a lightyear (as a measurement of distance) must be properly
tied to an actual distance standard like 9.4E15 meters or 5.6
quadgillion wavelengths of the red neon emission.

Dwib

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