Monday, August 6, 2018

Paul Dirac and mathematical physics


Photo source: Wikimedia Commons, Nobel Foundation

Paul Dirac (1902-1984) was a British physicist best known for his contributions to antiparticles and quantum mechanics. He is also known for predicting anti-matter. Physicist Richard Feynman said,
"When I was a young man, Dirac was my hero. He made a breakthrough, a new method of doing physics. He had the courage to simply guess at the forms of an equation, the equation we now call the Dirac equation, and to try to interpret it afterwards." (The Reason for Antiparticles)
Stephen Hawking said,
"Dirac has done more than anyone this century, with the exception of Einstein, to advance physics and change our picture of the universe." (Quoted in Paul Dirac: The Man and His Work by Peter Goddard)
The rest of this post is some quotes from Dirac.

Mathematics


"Just by studying mathematics we can hope to make a guess at the kind of mathematics that will come into the physics of the future." (The Evolution of the Physicist's Picture of Nature, 1963)

"It seems to be one of the fundamental features of nature that fundamental physical laws are described in terms of a mathematical theory of great beauty and  power, needing quite a high standard of mathematics for one to understand it. You may wonder: why is nature constructed along these lines?" (The Evolution of the Physicist's Picture of Nature, 1963)

"God used beautiful mathematics in creating the world." (Quoted in the Cosmic Code by Heinz Pagels)

"I think its a peculiarity of myself that I like to play about with equations, just looking for beautiful mathematical relationships which maybe don't have any physical meaning at all. Sometimes they do." (Interview with Thomas Kuhn, 1963)

"My research work was based in pictures. I need to visualize things and protective geometry was often most useful e.g. in figuring out how a particular quantity transforms under Lorenz transformation." (Recollections of an Exciting Era Lecture at Vareena, 1971)

Quantum mechanics


"Nevertheless, it has been found possible to set up a new scheme, called 'quantum mechanics', which is more suitable for the description of phenomena on the atomic scale and which in some respects more elegant and satisfying than the classical scheme." (The Principles of Quantum Mechanics, 1958)

"Some day a new quantum mechanics, a relativistic one, will be discovered in which we sill not have these infinities occurring at all. It might very well be that the new quantum mechanics will have determinism in the way that Einstein wanted." (Quoted in Albert Einstein: Historical and Cultural Perspectives by Gerald James Holton and Yehuda Elkana)