I think the problem is that "time scale" is not defined. It could be a scale that can be used both to indicate when events occurred or will occur, and to find durations by subtracting the beginning time from the ending time, and during any duration of the same number of seconds, physical processes such as the cycles emitted by an atomic clock will progress to the same degree. But it could instead refer only to a scale used by people to record events and plan for future events, without any implication that two durations that are nominally the same number of seconds will have physical processes progress to the same degree. UT1 is satisfactory for most event recording and planning purposes.
Gerard Ashton -----Original Message----- From: leapsecs-boun...@leapsecond.com [mailto:leapsecs-boun...@leapsecond.com] On Behalf Of Harlan Stenn Sent: Wednesday, May 08, 2013 10:36 PM To: Leap Second Discussion List Subject: Re: [LEAPSECS] drawing the battle lines (Found unsent in my Drafts folder...) Warner Losh writes: > I think the real reason that UT1 shouldn't be considered a time scale > is that it is based on not an imperfect realization of a fixed length > second, but rather an imperfect realization of a variable (measured by > oscillations of a fixed frequency) length second. Warner, I think your position is only valid form the point of view that says a timescale can only be used to count fixed-length seconds. If one considers a timescale as a counting of days it's a bit different. Then we get to look at leap years, and the adjustment made at the beginning of the Gregorian calendar. Would it be appropriate to say that these issues are more about 'cardinal' v. 'ordinal'? And then, if you are on one side of the issues, the other side is clearly wrong. Look at how badly people got leap year calculations wrong before Y2K. H _______________________________________________ LEAPSECS mailing list LEAPSECS@leapsecond.com http://six.pairlist.net/mailman/listinfo/leapsecs _______________________________________________ LEAPSECS mailing list LEAPSECS@leapsecond.com http://six.pairlist.net/mailman/listinfo/leapsecs