Radiometric dating youtube
Roman poet Lucretius, intellectual heir to the Greek atomists, believed its formation must have been relatively recent, given that there were no records going back beyond the Trojan War.The Talmudic rabbis, Martin Luther and others used the biblical account to extrapolate back from known history and came up with rather similar estimates for when the earth came into being.
He was one of the dominant physicists of his time, the Age of Steam.
The third act sees the entry of a newly discovered set of physical laws—those governing radioactivity.
Radioactivity offered not only a resolution to the puzzle of the earth’s energy supply but also a chronology independent of questionable geologic assumptions and a depth of time more than adequate for the processes of evolution.
His achievements ran from helping formulate the laws of thermodynamics to advising on the first transatlantic telegraph cable. Shelton was a philosopher of science, critical (as shown in his contribution, the 1915 article “Sea-Salt and Geologic Time”) of loose thinking and a defender of evolution in debates.
Harlow Shapley, who wrote an article in 1919 on the subject, was an astronomer, responsible for the detection of the redshift in distant nebulae and hence, indirectly, for our present concept of an expanding universe. Russell, author of the 1921 article on radioactive dating, was familiar to me for his part in developing the Hetzsprung-Russell diagram for stars, but I was surprised to discover that he was also the Russell of Russell-Saunders coupling, important in atomic structure theory. The prologue to the drama is the mid-19th century recognition of the relation between heat and other kinds of energy (see the 1857 article “Source of the Sun’s Heat”).
One referred to the depth of the sediments and the time they would have taken to accumulate; the other referred to the salinity of the oceans, compared with the rate at which rivers are supplying them with sodium salts.