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NBtarheel_33 2011-08-04 07:28

Milestone Countdowns
 
How are the milestone countdown numbers calculated? For example, what figures would I need to sum up in order to calculate the number of first-time tests remaining below 50M? How about the number of doublechecks remaining below 50M?

In other words, how do LL-ERR results figure in? And does an exponent that has *never* been tested count twice towards the doublecheck countdown?

Thanks!!

Prime95 2011-08-04 11:48

I believe LL-ERRs are included in the countdown total.

Never tested exponents are only counted once in double-check counts.

davieddy 2011-08-04 12:54

Milestone watching (my view)
 
If you had 50 radioactive nuclei with half life ~ 1 year,
when will the last one decay?

(Ignore poaching and the Quantum Zeno Effect)

David

wblipp 2011-08-04 14:38

[QUOTE=davieddy;268291]If you had 50 radioactive nuclei with half life ~ 1 year, when will the last one decay?[/QUOTE]

I get a mean of 6.49 years, a median of 6.18 years, and an inter-quartile spread of 5.19 to 7.45 years.

davieddy 2011-08-04 15:00

[QUOTE=wblipp;268298]I get a mean of 6.49 years, a median of 6.18 years, and an inter-quartile spread of 5.19 to 7.45 years.[/QUOTE]

As I surmized: watching paint dry or grass grow:smile:.
And your result ties in with 50 ~ 2^6

OTOH, the DC wave advances at an easily monitored rate,
and from front to straggly tail, the waveform remains roughly the same
length. This provides a simple way of estimating when the "countdown"
may be expected to reach 0.

David

OK I'll have quantitative stab at checking your result.

After 6.18 years I expect 0.69 nuclei still pregnant.
(Or should that be 1 nucleus 0.69 pregnant?).
Probability of 0 pregnant = 0.5
Sounds plausible to me..

Uncwilly 2011-08-04 23:49

[QUOTE=davieddy;268291]If you had 50 radioactive nuclei with half life ~ 1 year, when will the last one decay?[/QUOTE]I think that it can be arranged such that it will be in about 6 to 18 months.:devil:

davieddy 2011-08-05 00:32

[QUOTE=davieddy;268291]If you had 50 radioactive nuclei with half life ~ 1 year, when will the last one decay?

(Ignore poaching and the Quantum Zeno Effect)

David[/QUOTE]

[QUOTE=Uncwilly;268359]I think that it can be arranged such that it will be in about 6 to 18 months.:devil:[/QUOTE]

I thought I'd covered most of the "get outs".

What did you have in mind?

David


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