Stephen Hawking, born on 8 January 1942,was an British cosmologist, and the director of research at center fortheoretical cosmology. He was also the Lucasian Professor of Mathematics at theUniversity of Cambridge. He passed away two years back in the month ofMarch.
Hawking worked on gravitational singularitytheorems, which demonstrated that singularity will occur in any solution toEinstein’s theory of General relativity. He along with Roger Penrose was ableto show that the universe started from a singularity, and there is asingularity at the center of black holes. They published this paper together in1970 after which Hawking was made fellow at prestigious Royal society at theage of 32 one of the youngest till date. It shocked many scientists includingHawking which he writes in his autobiography “My Brief History”.
After working on general relativity, healso worked on quantum field theory on curved spacetime. Here the spacetime wasstill classical, but matter fields, were quantum mechanical. He was able toshow that black holes radiate a radiation, which was named after him as Hawkingradiation. This also meant that black holes would evaporate with passage oftime. This lead to the famous black hole information paradox. The black holeinformation paradox stated that information would be lost in a black hole.
He worked on quantum gravity during thelater parts of his life, and developed an interesting formalism calledEuclidean Quantum Gravity. In this formalism, one arrives at a specific threedimensional geometry by summing over all four dimensional geometries that joinit. Even though this did not work as planed, it still lead to many interestingresults. Some of those results are still used in modern approaches to quantumgravity.
He also had suggested that virtual blackhole would form due to quantum fluatuations in the spacetime, and they wouldform at any place in space. Thus, all places in spacetime would be filled witha certain density of virtual black holes. He tried to analyze many consequencesof this model, and this model has been used in particle physics, to explaindecay of a proton.
Hawking had a rare slow-progressing form ofmotor neuron disease, which gradually paralysed him at the age of 21. Butdespite being paralyzed for 55 years of his life, he made fundamentalcontribution to our understanding of universe, particularly to the subject ofblack hole physics.
Despite remaining engrossed in doingscience throughout his life Hawking never remained apolitical in hislife. In 2013, he boycotted a conference in Jerusalem where ShimonPeres, the late Israeli president was honoured. This made internationalheadlines. Hawking did this as he was critical of state of Israel and a supporter of BDS moment against state of Israel. An anti capitalist, hespoke and advocated for many issues like Artificial intelligence, globalclimate exchange and space colonies. He was a scientist with concern for peopleirrespective of their religion, creed, caste and colour. For his contributionto the fundamental physics he was awarded the prestigious Fundamental prize inyear 2012.