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Path: utzoo!watmath!clyde!floyd!harpo!seismo!uwvax!heurikon!jeff
From: jeff@heurikon.UUCP
Newsgroups: net.physics
Subject: Atomic clocks - Who knows if they're correct?
Message-ID: <229@heurikon.UUCP>
Date: Thu, 16-Feb-84 01:53:14 EST
Article-I.D.: heurikon.229
Posted: Thu Feb 16 01:53:14 1984
Date-Received: Sat, 18-Feb-84 03:21:19 EST
Organization: Heurikon Corp., Madison WI
Lines: 27


Einstein's Universe was on TV (again) last week.  I pick
up a little bit more each time I watch it.  But, I have a
question about atomic clocks and what the heck the correct
"time" means:

What if the NBS atomic clock went out?  A power failure
perhaps, or a critical component goes berserk.  They have
a backup clock, you say?  Okay, make it a catastrophic
event like an earthquake.  Anyway, *ALL* the NBS clocks stop.
(Also, assume that our sister atomic clocks in Europe also
go on the fritz or were down for maintenance.  Let Murphy
loose:  "Previously unneeded backup systems will all fail at
the same instant the primary unit looses power.")

How would they reset the NBS clock?  And how would anyone know
if it was set correctly?  What would be used as a standard?
And what problems would develop it it were wrong, anyway?
I know it's important to have syncronization between various
places or events, but what's so important about knowing what
time it is in *absolute* terms?

Post responses, please. Thanks.
-- 
/"""\	Jeffrey Mattox, Heurikon Corp, Madison, WI
|O.O|	{harpo, hao, philabs}!seismo!uwvax!heurikon!jeff  (news & mail)
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