[time-nuts] NPR Story I heard this morning

[Attila Kinali]

On Mon, 3 Nov 2014 11:54:41 -0800
Peter Monta <pmonta at gmail.com> wrote:

> Sorry if this is a bit off-topic.  I'd like a simple, clear explanation for
> the layman that drills down on exactly how the current definitional scheme
> can be realized to arbitrary precision.  For example, assume that we must
> go off-earth at some point to get a better timescale.  How fuzzy is the
> solar potential ("soloid")?

It will be done as usual: As soon as they can reliably measure an systematic
effect that is impossible to cancel out, they will redefine or ammend the
definition of the second to account for this issue.

And going by the presentations given at EFTF this year, there is quite
some interest in precision gravity measurements in the time/frequency
community. And yes, they use the same basic phyiscs as their atomic clocks :-)
(one apporach is to let Cs atoms fall down a tube and measure their
acceleration using doppler shift of the hyperfine transitions line)

			Attila Kinali

-- 
I pity people who can't find laughter or at least some bit of amusement in
the little doings of the day. I believe I could find something ridiculous
even in the saddest moment, if necessary. It has nothing to do with being
superficial. It's a matter of joy in life.
			-- Sophie Scholl