The uncertainties associated with direct half-life determinations are, in most cases, still at the 1% level, which is still significantly better than any radioisotope method for determining the ages of rock formations. However, even uncertainties of only 1% in the half-lives lead to very significant discrepancies in the derived radioisotope ages. We need to explore just how accurate these determinations are, whether there really is consensus on standard values for the half-lives and decay constants, and just how independent and objective the standard values are from one another between the different methods. “Absolute Ages Aren’t Exactly.” Science 282 (5395): 1840–1841. Of course, it is to be expected that every long-lived radioactive isotope is likely to show similar variation and uncertainty in half-life measurements because these are difficult measurements to make. Thus, all these radioisotope dating methods cannot be used to reject the young-earth creationist timescale, especially as current radioisotope dating methodologies are at best hypotheses based on extrapolating current measurements and observations back into an assumed deep time history for the cosmos. Instead, the actual observable experimentally-determined radioisotope decay data suggest that radioisotope decay rates have been decreasing in recent decades. Yet much research effort remains to be done to make further inroads into not only uncovering the flaws intrinsic to these long-age dating methods, but towards a thorough understanding of radioisotopes and their decay during the earth’s history within a biblical creationist framework. “The Isotopic Composition of Natural Uranium Samples—Measurements Using the New n(U) Double Spike IRMM-3636.” International Journal of Mass Spectrometry 269 (1–2): 145–148. One crucial area the RATE project did not touch on was the issue of how reliable have been the determinations of the radioisotope decay rates, which are so crucial for calibrating these dating “clocks.” Indeed, before this present series of papers (Snelling 2014a, b; 2015a, b; 2016) there have not been any attempts in the creationist literature to review how the half-lives of the parent radioisotopes used in long-age geological dating have been determined and to collate all the determinations of them reported in the literature to discuss the accuracy of their currently accepted values.
In order to rectify this deficiency, Snelling (2014a, b; 2015a, b; 2016) has documented the methodology behind and history of determining the decay constants and half-lives of the parent radioisotopes K which are used as the basis for the Rb-Sr, Lu-Hf, Re-Os, Sm-Nd, K-Ar, and Ar-Ar long-age dating methods respectively. “Isotopic ‘Fingerprints’ for Natural Uranium Ore Samples.” International Journal of Mass Spectrometry 193 (1): 9–14.
Yet these can supposedly be circumvented somewhat via the isochron technique, because it is independent of the starting conditions and is claimed to be sensitive to revealing any contamination, which is still significantly better than any radioisotope method for determining the ages of rock formations.
Data points that do not fit on the isochron are simply ignored because their values are regarded as due to contamination.
But there have still been repeated calls for more modern, more accurate direct counting experiments to more precisely determine the U half-life by forced agreement of Rb-Sr, Lu-Hf, Re-Os, Sm-Nd, K-Ar, and Ar-Ar ages respectively with U-Pb ages obtained for the same rocks, minerals and meteorites, none of these decay half-lives are really known accurately. “New Average Values for n(U) Isotope Ratios of Natural Uranium Standards.” International Journal of Mass Spectrometry 295 (1–2): 94–97.
Therefore, without accurately known decay half-lives, all radioisotope ages cannot be accurately determined or be considered absolute ages.