On Sep 3, 2010, at 1:04 AM, Ian Batten wrote: > I have a clock ticking SI seconds at arbitrarily high precision and > resolution.
Examine your premises. At some point in the past five years or so there was a thread discussing the distinction between clocks and timers. I won't attempt to recover the subtleties of that thread at this time of night. (Though I suppose the ITU would assert that my biorhythms are immaterial :-) > How do I find out how many SI seconds I should count in order to count ten > UT1 seconds? Can I determine that value prospectively, or only > retrospectively? Suppose a timer to be a standalone source of ticking SI seconds. A "clock" implies subjugating that timer to an external discipline such as mediated by NTP, for example. Supplying a discipline from an ensemble of officially blessed atomic clocks is no better than applying a discipline from the wobbling Earth. (The clocks may be more stable, but they are guaranteed to be shorter lived if nothing else :-) In particular, constructing an ensemble timescale is as retrospective a task as measuring the meridian transit of fiducial stars in support of calculating UT1. Here's an interesting preprint (http://arxiv.org/abs/1008.4686) with pertinence to the feasibility of fitting a model to data of putatively "arbitrarily high precision and resolution". Rob _______________________________________________ LEAPSECS mailing list LEAPSECS@leapsecond.com http://six.pairlist.net/mailman/listinfo/leapsecs
