The stunning improvements in the performance of mass spectrometers during the past four or so decades, starting with the landmark paper by Wasserburg et al.
(1969), have not been accompanied by any comparable improvement in the accuracy of the decay constants (Begemann et al.
Ironically it is the slow decay rates of isotopes such as Rb used for deep time dating that makes precise measurements of their decay rates so difficult. Reinvestigation of the decay of the long-lived odd-odd Lu nucleus.
2001; Steiger and Jäger 1977), in spite of ongoing attempts (Miller 2012).
The uncertainties associated with direct half-life determinations are, in most cases, still at the percent level at best, which is still significantly better than any radioisotope method for determining the ages of rock formations.
However, an insight from dynamical systems theory now allows us to circumvent the classical challenges of unravelling causation from multivariate time series.
We show that such variable time lags are typical for complex nonlinear systems such as the climate, prohibiting straightforward use of correlation lags to infer causation.
The recognition of an urgent need to improve the situation is not new (for example, Min et al. It continues to be mentioned, at one time or another, by every group active in geo- or cosmochronology (Schmitz 2012).