Rob Sheldon
Is a new “muon” finding evidence for a fifth force of nature? Rob Sheldon weighs in
Rob Sheldon reflects on skepticism about the findings from research brain scans (fMRI)
Rob Sheldon takes aim at black holes: How much is really known?
Sabine Hossenfelder asks, Should Stephen Hawking have won the Nobel? Rob Sheldon weighs in
Rob Sheldon: Biologists’ use of the term “half-life” shows just how tenuous many of their propositions really are
Recently, our physics color commentator Rob Sheldon took issue with the use of the term “half-life” to describe the survival of DNA in fossils. He says the term has a specific meaning with respect to radioactive decay that just does not apply to other events in nature. In the biology paper at issue, with “half-life” in the name, the authors explain and use the concept in connection with radiocarbon dating: Abstract: Claims of extreme survival of DNA have emphasized the need for reliable models of DNA degradation through time. By analysing mitochondrial DNA (mtDNA) from 158 radiocarbon-dated bones of the extinct New Zealand moa, we confirm empirically a long-hypothesized exponential decay relationship. The average DNA half-life within this geographically constrained Read More ›