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Article #430

Re: Synchonizing watches

#430
From: pds
Date: Fri, 04 Sep 1992 14:08
25 lines
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In article <1992Sep3.201917.25468@hubcap.clemson.edu>, mailrus!samsung!ulowell!cs.ulowell.edu!wex@uunet.UU.NET (Paul M. Wexelblat) writes:

> OK A --->B:  "I'm going to say "BONG" as soon as my second hand
> reaches the 12, when you hear the "BONG", start counting seconds
> on your watch out loud.
> 
> A says "BONG" and times AB+BA seconds; at the end of that time the number
> B has reached is the BA delay

I don't think so.  A says "BONG" at t=0.  At t=AB, B hears "BONG" and
starts counting, saying "zero" at t=AB, "one" at t=AB+1, ...
A will hear "zero" at time AB+BA  - there is no way for A to know
what number B has reached because A won't hear it for another BA seconds.

I think the earlier proof that no solution exists looked right.

Patrick

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From: pds@epcc.edinburgh.ac.uk
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Subject: Re: Synchonizing watches
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Date: 4 Sep 92 14:08:47 GMT
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