Lexicon of Arguments

 

I 474
Aberration: a telescope must be slightly tilted in the direction of movement of the earth.
((s) while the light is traveling in the telescope, the entire system moves "to the right", i.e., the light enters the eyepiece in the "second" telescope drawn to the right of it.)
Feynman: "squashed ruler".
Because of the contraction effect:

tan Θ = v/c
√ (1 - v²/c²)
or

sin Θ = v/c.

I 475
Objectivity/Objective/Measuring/Aberration/Feynman: how can we say objectively where the star "is" at all?
Solution: 6 months later we have to tilt the telescope in the other direction because of the earth's movement around the sun. This is the only reason why we can determine aberration at all.
>Measurements, >Method.