Re: The SR between reality and appearance

Op 17/09/2023 om 10:26 schreef Luigi Fortunati:

wugi il 10/09/2023 08:37:40 ha scritto:

A simple and clear example is the following.
>
If observer B1 stands on the carousel, he sees the earth rotate a full
360 degrees in 5 seconds and sees the carousel stationary.
>
Instead, observer A on the ground sees the carousel rotate 360 degrees
in 5 seconds and sees dry land.
>
One sees one thing, the other sees another: can both be real? Obviously
not.

>
No indeed, "obviously" there are only appearances.
>

If what observer A sees is real, what observer B1 sees can only be
apparent.
>
In fact, if the Earth really rotated at that angular velocity, it would
shatter!

>
Would it? You forget that with Earth, the whole universe is rotating
around B1, so that ultimately it is only B1 who is feeling the "real"
rotational force acting upon them, from Earth + Universe.

 
I am so naive that I have always believed that the man on the in
movement carousel feels the rotational force of the carousel and not
that of the Earth + Universe.

(A late one). He feels the reaction force by Earth+Universe upon the
carousel's rotational action, transmitted through the carousel's
foundation and its own stiffness.
Compare with the water in the bucket, which doesn't feel the bucket's
swinging action, but rather the reaction upon the bucket by the rope, by
the hand, by the person swinging the bucket around, by the floor
retaining his feet, by Earth, ...

--
guido wugi