How ‘social distancing’ during the Great Plague led to Newton’s theory of gravity

Similar to the measures being taken during the current coronavirus pandemic, Sir Isaac Newton was in his early 20s when he was sent home from Cambridge when the Great Plague hit London.

According to the Washington Post, it was during this time, confined in his home, that Newton made some of his greatest discoveries, including gravity.

It was in 1665 during the Great Plague that Cambridge sent students home as a precautionary measure. Newton returned to his family estate, Woolsthorpe Manor, about 60 miles northwest of Cambridge, where he then thrived.

The year 1666, which he spent away from Cambridge at his estate, is termed as Newton’s annus mirabilis, his “wonder year” when he began work on his discoveries in the fields of calculus, motion, optics and gravitation.

The mathematical papers he wrote during this time went on to form the early foundations of calculus.

He then experimented with a few prisms in his bedroom, going so far as to punch a hole in his shutters for a small light beam to come through. This led to his theories in optics.

Outside his window at Woolsthorpe Manor was ‘the apple tree’ that led to the discovery of gravity.

According to a draft account of Newton’s life by his assistant John Conduit, as published by the Newton Project, “In the year he retired again from Cambridge on account of the plague to his mother in Lincolnshire & whilst he was musing in a garden it came into his thought that the same power of gravity (which made an apple fall from the tree to the ground) was not limited to a certain distance from the earth but must extend much farther than was usually thought.”

A quarter of London’s population perished in the Great Plague of 1665 and 1666. Newton returned to Cambridge in 1667, and was made a fellow within six months of his return.

The current COVID-19 pandemic has affected over 140 countries worldwide, with more than 1,53,000 confirmed cases worldwide and a death toll of over 5,700, according to the World Health Organisation.