Orest Khvolson

Born on 4 December 1852 in St Petersburg, Russia, Orest Khvolson (alternate spelling Chwolson) was one of the first scientists to study the gravitational lens effect. Khvolson was the son of Daniel Chwolson, a noted scholar in East Asian studies. Khvolson graduated from St Petersburg University in 1873. He went on to teach there for almost 60 years, attaining full professorship in 1891. In 1920 he was made an honorary member of the Soviet Academy of Sciences. He published extensively on electricity, magnetism, photometry, and actinometry but is best known for his five-volume Physics Course, which formed the foundation for the teaching of physics in the Soviet Union for many years and was translated into French, German, and Spanish. In 1924 Khvolson published his groundbreaking paper on gravitational lensing , a phenomenon whereby the gravity of a massive object positioned between a distant light source and an observer deflects the light’s path and acts as a magnifying lens. The object is often surrounded by an arc, which has been called a Chwolson ring or, more popularly, an Einstein ring. Albert Einstein more clearly spelled out the gravitational lensing effect, which is a consequence of general relativity, in a 1936 paper .

Date in History: 4 December 1852