SHARE

Showing posts with label Physics. Show all posts
Showing posts with label Physics. Show all posts

Tuesday, January 10, 2012

Universe is the work of physics, not God: Stephen Hawking

'Scientific superstar' Stephen Hawking turns 70 on 8 January 2012.

நமது காலத்தின் மாபெரும் பெளதீக விஞ்ஞானி Stephen Hawking இற்கு இனிய 70ம் ஆண்டு பிறந்தநாள் நல் வாழ்த்துக்கள்!

Stephen Hawking at 70: still the brightest star in the scientific universeAs the author of A Brief History of Time approaches 70, eminent former students celebrate an awe-inspiring intellect still pushing at the frontiers of physics
================
BERNARD CARR
Professor of mathematics and astronomy, Queen Mary, University of London. Stephen Hawking's PhD student 1972-75
================
Stephen's discovery in 1974 that black holes emit thermal radiation due to quantum effects was one of the most important results in 20th-century physics. This is because it unified three previously disparate areas of physics – quantum theory, general relativity and thermodynamics. Like all such unifying ideas, it is so beautiful that it almost has to be true, even though it has still not been experimentally confirmed. The renowned physicist John Wheeler once told me that just talking about it was like "rolling candy on the tongue".

At the time of the discovery, I was working with him as a PhD student in Cambridge and I count myself as very fortunate to have had a ringside seat during these developments. It also enabled me to be one of the first people to study the cosmological consequences of the effect and thereby make my own small contribution to the subject.

I was one of Stephen's first PhD students and people often ask me what it was like having him as a supervisor. He was not so famous in those days but his brilliance was already clear to his peers and I found it rather daunting when, on becoming his research student, I was informed by one of my tutors that he was the brightest person in the department. Students are probably always in awe of their supervisors but with Stephen the awe was even greater. Indeed, on matters of physics, I always regarded him as an oracle, just a few words from him yielding insights that would have taken weeks to work out on my own.




However, Stephen is only human and not all encounters led to illumination. Once, while sharing an office with him at Caltech [California Institute of Technology], I asked a question about something that was puzzling me. He thought about it silently for several minutes and I was quite impressed with myself for asking something that Stephen couldn't answer immediately. His eyes then closed and I was even more impressed with myself because he was clearly having to think about it very deeply. Only after some time did it become clear that he had fallen asleep! Nowadays I also sometimes fall asleep while talking to students, so I recall this incident with amusement.

The other human side of Stephen is that he does occasionally get annoyed. One of the myths put around is that he sometimes vents his frustration by running over the toes of students. This never happened to me – he didn't have a motorised wheelchair in those days – but I well recall one occasion when I made a remark in the maths common room at tea-time that showed that I had misunderstood what he'd been saying. Stephen screamed "No" so loudly that his wheelchair shot back halfway across the room under the recoil. I was most impressed that a single word from him could have such dramatic consequences.

My relationship with Stephen was not the usual type of supervisor-student relationship. In those days, before he had his entourage of nurses and assistants, students would necessarily have to help him in various ways on account of his disability. This was not an arduous task but it did mean that one's relationship with him became quite intimate. I shared an office with him, lived with his family for a year in California, and accompanied him as he travelled around the world, giving talks and collecting medals.

As an impressionable young student, it was a tremendous thrill to meet so many celebrities and renowned physicists. One of the great excitements of visiting Caltech, where Stephen was a Fairchild scholar in 1975, was meeting the brilliant physicist Richard Feynman, who was regarded almost like a god there. He used to visit our office quite often and, since Stephen's voice was already quite weak, I would act as interpreter.

I also travelled around China with him in 1985. During a long train journey, I recall reading the first draft of a popular book he was writing at the time. My initial impression that it would never sell proved inaccurate since it eventually turned into A Brief History of Time!

Shortly after his return from China he fell seriously ill with pneumonia and lost his voice. Ever since, he has had to communicate through his computer, which is painfully slow, so it's ironic that he has still managed to become one of the great science popularisers of our age. He has even written books for children with his daughter, Lucy, and it is sobering to reflect that a contribution I wrote for their most recent one has probably been read by more people than any of my scientific articles. His inspiration of public interest in some of the deepest questions of physics is certainly one reason why he has become such an iconic figure.
The Observer, Sunday 1 January 2012

India, Sri Lanka head to a win-win relationship

India, Sri Lanka head to a win-win relationship 《  Asian Age 17 Dec 2024  》 All the signs are pointing to the possibility of a major win for...