Presentation #236.02 in the session HAD II - Centennial of an Eclipse: The 1922 Expedition that Clinched the Case for General Relativity.
The eclipse test of general relativity is generally acknowledged as one of the key experiments of the 20th century. It is not surprising therefore that replication of this experiment remained an objective of many astronomers for many decades. Indeed such was the importance of replication in this case that it has been claimed that the Lick Observatory’s measurement of 1922 counts as even more important than the famous expeditions of 1919. This talk will chart the course of replications of this experiment in the 20th century. The aims of the expeditions aiming to replicate the experiment changed with time. Up until 1929 the goal was to confirm (or the opposite) the falsification of Newtonian gravity by the original teams of 1919. From 1936 to 1955 the aim was to improve certain technical aspects of the experiment to provide a check on the confirmation of general relativity established (but with caveats) in the previous era. From 1955 to 1970 there may have been a hiatus. In 1970 and 1973 a new era of theory testing dawned with the effort to test the Jordan-Brans-Dicke theory. After 1973 radio astronomers measuring occulting quasars took over the field and there was no longer a need for professional astronomers to mount such expeditions.