[LEAPSECS] drift of TAI

[David Malone]

> The problem there is in suddenly being 4 hours out of synch with the

> sun, and having to shift phase.  Phase shifting is difficult.  I think

> people are much more flexible about diurnal frequency than you think,

> especially if the appropriate cues are around to support it.


The cueues for this frequency shift look just like a 4 hour phase
shift every day. Of course, there could be a long-term adaption
I guess.


> There's some fairly well-known research to the effect that the human

> biological clock actually has a natural period of 26 hours or so,

> and its only our exposure to planetary rotation that keeps us on a 24

> hour cycle.


AFAIK, that research has been shown to be flawed.


> I've previously mentioned on this list that my personal

> free-running diurnal cycle is 40 hours, empirically determined when I

> was an undergrad and had no daily responsibilities.


Unless you were living divorced from daylight, it's unlikely this
is your natural period.  According to this article (found via
wikipedia):

	http://www.hno.harvard.edu/gazette/1999/07.15/bioclock24.html

95% of people have a natural period of 24h11m +/- 11 minutes, though
the range went from 13 to 65 hours. The article also suggests that
a 28 hr day is long enough to prevent people's hormones getting in
sync with the day. I'm not sure what the practical implications of
this are.

	David.