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During the discussions leading to the inception of the SI second the bigwig standards folks nixed the consideration of relativity, basically paraphrased as "If you physicists do no…

Strange is what they said just after the CCIR incepted leap seconds at the SI subcommittee in charge of the subject: "The CCIR may have overstepped its remit in defining the UTC" a…

Have a look at the rate of earth rotation over the past 250 years where it is unclear that there is long term acceleration or deceleration. https://www.ucolick.org/~sla/leapsecs/du…

It is possible 8 weeks in advance to predict the difference between UTC and UT1 and keep it less than 0.9 seconds. Nothing more is required by international agreement.

Lack of agreement; "smearing" is completely normal for answering "What time is it?", and completely wrong for applications requiring precise time.

In that case UTC is the wrong answer to the question "What timescale will produce robust results for this application?" As soon as leap seconds were recommended by the CCIR in 1970…

Look at the past 250 years where there is not really any clear indication of deceleration https://www.ucolick.org/~sla/leapsecs/dutc.html

Calculating time deltas between events is fundamental for GPS navigation, tracking an incoming missile, coordinating the action of robotic systems, synchronization of telecommunica…

"ignoring leap seconds" is equivalent to "using a time scale that does not conform to UTC". Time scales other than UTC have 86400 seconds in a day. UTC is the exception.

"My system clock is wrong, what action shall I take to correct it?" Common answers to that question are "step" or "smear". The notion that the clock could be wrong is not addressed…

At the inception of leap seconds it was unclear how well they could be predicted, but the agreement required 8 weeks of notice as a minimum. Since the inception of leap seconds the…

POSIX requires that we ignore leap seconds. POSIX had no alternatives to this choice because the information needed to do time right was not, and still is not, readily available vi…

A detailed look at the negotiations that led to leap seconds shows that they were not for maritime celestial navigation. During the process several different times the celestial na…

In 1950 astronomers pointed out that there would have to be two kinds of time, one to agree with calendar days and one to be as uniform as possible. Arguments over subsequent decad…

Yes, roughly quadratic increase of LOD over the long term, but over short term more like a random walk. Right now the earth's crust is rotating faster than it did a century ago bec…

Remember February 30 1712? https://en.wikipedia.org/wiki/February_30#Swedish_calendar

The ITU has 4 methods for dealing with leap seconds, and method D is to change nothing. See the lack of consensus for any change in last week's presentations at http://www.itu.int/…

Dan Bernstein proposed it and Bradley White wrote the code in the time zone package used by Unix-like systems. The point of "right+gps" is that all of the pieces needed to implemen…

Some delegates to the ITU-R process have argued in the above fashion. Other delegates have come representing countries which want UTC to remain as a valid count of days in the cale…

There have been many defintions of UTC http://www.ucolick.org/~sla/leapsecs/timescales.html#UTC which do not agree. When an API does not match what the providers supply, which defi…

Read between the lines of http://www.bipm.org/cc/CCTF/Allowed/18/CCTF_09-27_note_on_UT... about what systems of time distribution already exist and which of those are approved for …

Getting a TAI timestamp is impossible because the BIPM (the authority that defines TAI) does not want TAI used for such purposes. Without approval from the authority nobody will un…