I came across a utube vid about this is 08 or so, a talk at a convention, and it intrigued me, but didn't know anyone was working on studying it. The guy set up a counter in the basement, and was tracking Cesium decay, to compare to a Web clock, IIRC. Can't find it now, topic is swamped, and duckgo swamped with creationist blogs, i guess they like the idea of radiodating flaws.
After many dueling papers, it appears the big neutrino sensor in Japan has seen the same, seasonal variability in their data too, so appearing more legit.
"Unexplained periodic fluctuations in the decay rates of 32Si and 226Ra have been reported by groups at Brookhaven National Laboratory (32Si), and at the Physikalisch–Technische–Bundesanstalt in Germany (226Ra). We show from an analysis of the raw data in these experiments that the observed fluctuations are strongly correlated in time, not only with each other, but also with the time of year."
and a review article, from the old Analog magazine!
Radioactive Decay and the Earth-Sun Distance
This paper consolidates the data on six of the studies, while taking some simple, EM measurements of the Plank length variation that seems to coincide fairly closely with the decay rate data. Both are trailing the actual distance measurements by up to a month, which is pretty strange in its own right.
Along with the Plank variation, lots of other explanations have been floated, my favorite being the link to a possible Dark Matter reservoir, that may reside in the Sun. This may also be one of the possible factors in the appearance of possible discrepancies in physics parameters at large Z regions of the universe, including some Type Ia supernova, that are used as distance markers.
The Sun Goes Through Seasonal Changes Too
Annual Modulation of Dark Matter: A Review
Constraining spacetime variations of nuclear decay rates from light curves of type Ia supernovae by Ivan Karpikov et al. [2015/01]
Radionuclides chart, with decay variations.
Sunspot numbers, java, I can't see if there is any alignment there, tho there was a paper on solar flares.
Perturbation of Nuclear Decay Rates During the Solar Flare of 13 December 2006�, Jere H. Jenkins and Ephriam Fischbach, arXiv preprint 0808.3156 [astro-ph], August 22, 2008.
and archives of solar data, someone might be able to find other correlations.
The same folks that did some original studies, also did a follow up, showing NO effect, but i guess that has been superseded. Someone also did a study on the Cassini RTG, but found no effect, tho with no internal access, and a U238 nucleotide, may not be as robust.
So, if decay rates are fluctuating, does that show that the simulation theory is not likely (not fine-grained enough), or that we don't even know what we don't know? Seems like a variable like this wouldn't be modeled in a sim...?