Re: Evil Twin Paradox


"Alen" <alen1@xxxxxxxxxxxxxxx> wrote in message
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On Aug 7, 5:41 pm, "harry" <harald.vanlintelButNotT...@xxxxxxx> wrote:
"Alen" <al...@xxxxxxxxxxxxxxx> wrote in message

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Instead of giving my usual argument, I will point to a problem
with their explanation that they never deal with. They say
that the wall rotates in spacetime,

That's mathematical language. I suspect that a majority of physicists
doesn't believe in a geometrical kind of ether in which space is
literally
mingled with time.

Then what do they believe? Do you agree with me
that Minkowski spacetime is not an actual, physical reality?

Minkowski diagrams are calculation aids. Many physicists simply want to
calculate and have stopped trying to make sense of things, and tend to take
things at face-value. For example Feynman even claimed: "I hope you can
accept Nature as she is - absurd."

so that it is almost at
'right angles' to the moving twin, so that the gap looks to
be almost completely closed, and thus the moving twin has
no chance to fire through such a narrow gap. But a question
is, what is the fulcrum of such a rotation, and how is it
specified or identified? If anyone says it is specified by the
twin who accelerates,

No, it's specified by the set of inertial frames.

Harald

If spacetime rotations are not supposed to be
physically real, then arbitrary fulcra of rotations
can be used as desired.

No, the rotation is determined by the Lorentz factor (and thus by the
speed).
Minkowski diagrams provide a handy graphical means to directly match clock
readings and distances of one inertial coordinate system with those of
another inertial system that moves relative to it (note that neither system
rotates!).

If, however, they are supposed
to be real, how does an inertial frame establish the
location of the fulcrum of its spacetime rotation relative
to another inertial frame, if it is not specified by an
object that accelerates into it?

I'm not sure if I understand your question, but perhaps I answered it here
above.

Regards,
Harald


.

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