Paul Dirac - In Our Time 5th March

[ardcarp]

Paul who? Well, he was a Brit (despite the name) a formidable mathematician, and he made major contributions to the understanding of quantum physics.

Melvyn Bragg and guests discuss the theoretical physicist Dirac (1902-1984), whose achievements far exceed his general fame. To his peers, he was ranked with Einstein and, when he moved to America in his retirement, he was welcomed as if he were Shakespeare. Born in Bristol, he trained as an engineer before developing theories in his twenties that changed the understanding of quantum mechanics, bringing him a Nobel Prize in 1933 which he shared with Erwin Schrödinger. He continued to make deep contributions, bringing abstract maths to physics, beyond predicting anti-particles as he did in his Dirac Equation.

https://www.bbc.co.uk/programmes/m000fw0p

[Bryn]

Paul who? Well, he was a Brit (despite the name) a formidable mathematician, and he made major contributions to the understanding of quantum physics.

Melvyn Bragg and guests discuss the theoretical physicist Dirac (1902-1984), whose achievements far exceed his general fame. To his peers, he was ranked with Einstein and, when he moved to America in his retirement, he was welcomed as if he were Shakespeare. Born in Bristol, he trained as an engineer before developing theories in his twenties that changed the understanding of quantum mechanics, bringing him a Nobel Prize in 1933 which he shared with Erwin Schrödinger. He continued to make deep contributions, bringing abstract maths to physics, beyond predicting anti-particles as he did in his Dirac Equation.

https://www.bbc.co.uk/programmes/m000fw0p

The sort programme Radio 3 used to do well. Paul Dirac a long-time intellectual hero of mine.

[Count Boso]

The sort programme Radio 3 used to do well. Paul Dirac a long-time intellectual hero of mine.

Hear, hear. If you want a thoroughly entertaining biography, Graham Farmelo's The Strangest Man is a great read. All the history/background to the quantum research of the day without it being necessary to be a mathematical genius to understand it.

[Jazzrook]

The sort programme Radio 3 used to do well. Paul Dirac a long-time intellectual hero of mine.

A fascinating programme.
It prompted me to order the book 'The Strangest Man' by Graham Farmelo, one of the contributors.

JR

[Quarky]

A very interesting programme, which told me a few things that I didn't know already. I have Dirac's book , which I dip into occasionally, but I came to the conclusion at an early age that the maths involved presented an insuperable obstacle to a complete understanding.

100 years on, and they are still working on the problems that he posed. The last time I looked, the view was that there is no such thing as solid matter - all matter, including human beings is just a manifestation of fields....

https://www.youtube.com/watch?v=FBeALt3rxEA

[ardcarp]

Thanks for the book recommendation Boso. Will get it.

Einstein had a difficult relationship with the quantum world, apparently. His well-known quote is "God does not play dice with the universe", but he also said something along the lines of "if anyone says he understands quantum theory, he's a liar". Can anyone find his actual words?

[gurnemanz]

I do find such programme fascinating to listen to - and watch on TV. I even have occasional fleeting insights into what these geniuses are on about but I am happy to admit that most of it is quite beyond me. I did do O level Physics (grade D) but I can't remember getting much beyond glass prisms, levers and pulleys.

I was slightly taken aback by the pronunciation of Erwin Schrödinger's surname that one of the expert contributors gave us. He ignored the umlaut and made it rhyme with "ginger" not "singer".

[Quarky]

Thanks for the book recommendation Boso. Will get it.

Einstein had a difficult relationship with the quantum world, apparently. His well-known quote is "God does not play dice with the universe", but he also said something along the lines of "if anyone says he understands quantum theory, he's a liar". Can anyone find his actual words?

Well, he may have done, but he made fundamental contributions to Quantum Theory all the way through, including the concept of the "photon", particles of light, and arguably was the first to formulate quantum theory.

His saying God does not place Dice was apparently in a letter to Max Born: A reprint of this book was published by Edition Erbrich in 1982, ISBN 3-88682-005-X

The saying Anyone says he understands Quantum Theory.... was not Einstein, but Richard Feynman?

Interesting for me was Einstein's Paper which he wrote to disprove Quantum theory. He formulated, but then criticised, Action at a Distance, as "Spooky". Well that is now known as Quantum Entanglement, and is key to current Quantum Computing research and engineering.

[gurnemanz]

Hear, hear. If you want a thoroughly entertaining biography, Graham Farmelo's The Strangest Man is a great read. All the history/background to the quantum research of the day without it being necessary to be a mathematical genius to understand it.

Could be up my street. I'm pretty sure I would get more out of the biography than trying to grasp the science. I enjoyed reading Heisenberg's War: The Secret History Of The German Bomb by Thomas Powers - useful background reading at the time (20 years ago) to Michael Frayn's play, Copenhagen, about Heisenberg's mysterious wartime meeting with Niels Bohr.

[ardcarp]

The saying Anyone says he understands Quantum Theory.... was not Einstein, but Richard Feynman?

Thanks for the correction Quarky. You are aptly named. My grasp on the subject is tenuous, but then.......

[Bryn]

Thanks for the correction Quarky. You are aptly named. . . .

Maybe but is it intended to be pronounced as in the dairy product or as 'kwork', which is how Murray Gell-Mann intended it to be enunciated?

[Count Boso]

Could be up my street. I'm pretty sure I would get more out of the biography than trying to grasp the science. I enjoyed reading Heisenberg's War: The Secret History Of The German Bomb by Thomas Powers - useful background reading at the time (20 years ago) to Michael Frayn's play, Copenhagen, about Heisenberg's mysterious wartime meeting with Niels Bohr.

Heisenberg passim in the Farmelo, of course, as it Bohr. As for the maths, I wasn't wholly at ease with A Brief History of Time, but as this is primarily biography any troublesome maths detail was eminently skippable.

[Quarky]

Maybe but is it intended to be pronounced as in the dairy product or as 'kwork', which is how Murray Gell-Mann intended it to be enunciated?

I'm glad my alias has a variety of interpretations. It was actually inspired by something Sarah Mohr Pietsch said. However I do have a degree or two in the subject under discussion. But probably three or four is necessary to really get to grips with it.

[ardcarp]

...interesting that Dirac took his first degree in engineering. Quite a guy to fly into the almost metaphysical realms of quarks, antimatter and all that stuff.

[Belgrove]

The maths behind Dirac’s contributions to physics can be appreciated by a first year science undergraduate. But understanding it’s meaning and implications requires a more mature perspective of the physical world. As to what inherent sense made Dirac select disparate areas of maths and weld them together to formalise and extend quantum mechanics, we can only speculate. But he was always motivated in his work by an exquisite taste for the beautiful. This sense was preternatural, being marked above all by elegance. The elegant all too frequently conceals a profound expertise and understanding, and takes work to reveal and comprehend its meanings.

Dirac was a rarity, a genius.

The contributors did well to convey his influential but abstract ideas.