# Falling elevator

1. Sep 17, 2010

### jensel

Helllo,

I have a simple question about... let's say understanding. I watched the video from Stanford University http://www.youtube.com/watch?v=hR7fWF_qBZI&p=6C8BDEEBA6BDC78D&playnext=1 where it is about a falling elevator. I can't see the problem... Susskind talks about an effect of second order which neglects or so...
If the elevator is free falling in a gravitational field there is no effect for the measurement in the elevator (if the dimension of the elevator is neglible), the speed of light is not impressed by the view of the visitors outside. The clocks are working perfectly in the proper time, which is a natural property.
From an external observer the elevator is accellerated so that we can, if the spatial dimension is not too big (without spezifying this), observe the elevotar as "test elevator", where we get no further effect than the current speed of the elevator.
I cannot see that for a long elevator (or an arbitrary system)

1. the observed proper time is that simple
2. that this has anything to do with a problem with the principle of aquivalence like Einstein said

About 1: An accelarating very fast rocket needs to be integrated over time, SRT given
About 2: Shame on me, I did not calculated it, but if the effect is of second order it has to be clarified.

Thanks for help in this issue!

Jens