On Wed, "Peter Kinane" wrote with a time machine,

or a day late and a dollar short computer, to himself;

"Peter Kinane" wrote in message
[snip]
If there is no common ground then in the first scenario, with FoR-spaceship,
light travels at c. With FoR-light, spaceship travels at c. In second
scenario, with FoR-Earth, light travels at c, and with FoR-light Earth
travels at c.

Now if light c is the common ground or FoR (FoR-c), then spaceship and Earth
have same speed.

Please set your clock, then reboot your brain.

If this is so, then where did Einstein go from here? If he makes Earth the
FoR, perhaps he then says (gedankens) that a spaceship observer - frame of
reference for light - "light travels at c in all directions", as you said.
And FoR-Earth can, given spacship v = 0, say that if it had velocity "the
image of the (interior) front of the spaceship will now travel towards me at
(c-v), whereas the image of the of the rear of the spaceship will travel
towards me at (c+v)".

As Dirk "all know [] since more than a century":
"Those are the closing speeds between light signals and an object.
Each light signal has speed c with respect to the observer on earth,
but the distances, as measured by the earth observer, between
the signals and an object or observer inside the ship, decrease or
increase at resp. rates c+v and c-v".

Perhaps Einstein then calls a new ball game, with For-Earth measuring light
= c. If he wants the spaceship to be measured at say .6c then the
FoR-spacship would need a funny clock or/and a funny rod, so as to cohere
with what FoR-Earth is measuring?

This is just a specualtion on A.E.'s fumbling, and an invitation for
comments.

Peter Kinane
http://www.effectuationism.com

So the infected air has reached Ireland, egos expanding
faster than brain?

And you agree with a guy that uses a layman book
as a reference?

Are there teachers in grade school giving problems
like this to get students to think for themselves, not realizing
that is impossible for some?

Joe Fischer