Re: Another Rotating Cylinder Problem - explain from moving frame view


"David" <dseppala@xxxxxxxxxxxxx> wrote in message
news:fitd42tm8aia1mggg3mlq9smdv9gral2g8@xxxxxxxxxx
On Wed, 19 Apr 2006 18:50:28 +0200, "Harry" <harald.vanlintel@xxxxxxx>
wrote:
SNIP
Actually in the train problem I posted you said to show some numbers
so I did and you did not reply. In the battery problem I posted my
explanation Harald replied saying he found my error but it appeared he
mis-interpreted what I had said. So I clarified the response and he
no longer replied.
I don't know how to search for archived threads and my
reader/service only shows the past 30 days or so, so I can't get the
full thread to post as a reference for you.
David

Hmm, your reply didn't show up in my newsreader. I now do see your reply,
but it doesn't appear as if I significantly misinterpreted what you said.
I'm not sure to recall the whole story correctly, but Bill's above remark
seems to be spot-on, for you wrote (if I'm not mistaken) about an
*accelerating* point: "From the moving end's point of view [...] "time"
is
measured to be slower at the other end".

In that problem the rates were constant, and then there was an
acceleration as in the twin's paradox and constant rates were resumed.

OK, thanks for refreshing my memory! Then here we face *again* the problem
that you made no real calculation, leaving only place for vague discussions.
If I understand well, you switched back to the more general problem of
mutual time dilation, and you seem to think that that doesn't work out for
the case of passengers entering a moving train and leaving it on one end.

If you repost that problem *with a full calculation* (according to SRT!) and
still obtain a contradiction then I and others are very likely to be willing
to have another look at it. And in case you manage to solve it, that will be
worth a posting too - just to show us that all this talking wasn't in vain!

Harald

That's no good: such statements are valid for inertial frames, but
not in general for accelerating points.

Harald




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