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### Subbing Paul Dirac

Galaxy Babe - eclectic editor Started conversation Jan 31, 2019

Hi Sasha

I have subbed your excellent entry on Paul Dirac here: A87928807

I found this text at the bottom - would you like me to delete it or leave it in place?

<!-- Quantum Theory - delving deep into matter, to the atomic level, Planck discovered that energy was not continuous, but was divided into pieces, that he called quanta.

Heisenberg considered Quantum Theory, and instead of trying to visualise the atom like Bohr had done, he instead looked at it from an abstract perspective and determined that matrices could be used to describe the atom behaviour (and discovered noncommutativity, which was not something that physics experienced in the large world, so pg-qp was not zero but was h/2pi i[Identity Matrix].

of cat fame developed a Wave Equation in Psi that described quantum properties of a system - functions of Psi could be used to determine the probability that a particle was in a given position and the probability that a given quantum state exists.

Dirac also looked at noncommutativity of matrices - wrote a paper and sent it to Heisenberg who was impressed at the elegance of it. 4 papers on quantum mechanics were put together as a thesis and Cambridge University awarded him PhD. Another paper - transformation theory - reconciled Heisenberg and Schrodinger theories as special cases of his more general theory.

Dirac also considered wave-particle duality of light and used Quantum Mechanics to reconcile that as well - considering his theory from a wave perspective yielded results for waves that had been deduced by others, and similarly for considering the theory from the particle perspective.

Working in St John's College, Cambridge - the Dirac Equation - guessed at by considering symmetry in Quantum Mechanics and Special Relativity to describe the behaviour of electrons moving at close to the speed of light, including the spin of 1/2 found from experiments, and indicated the existence of a particle like the electron but with positive charge - the positron was discovered in experiments in 1932. Dirac and Schrodinger awarded Nobel Prize in 1933.

Paul also spent time in Germany in 1926/7, where he met Robert Oppenheimer, then a PhD student. Paul returned to Cambridge in October 1927 and started trying to link Relativity and Quantum Mechanics together.

Antimatter - attempt to combine quantum mechanics and special relativity

He featured on stamps, had his portrait painted and two busts were made - one still in St John's Cambridge. He declined a knighthood but became a member of the Order of Merit

-->

### Subbing Paul Dirac

SashaQ - happysad Posted Jan 31, 2019

Thanks GB - much appreciated

Yes, you can delete the text as it is just my notes from when writing the Entry so it is not needed in this version

### Subbing Paul Dirac

SashaQ - happysad Posted Jan 31, 2019

Thanks GB

I spotted one of my sentences that could be improved with a bit of a tweak, please.

"His favourite lectures were the theoretical ones2 - he often went to the library to work on problems by himself, aiming to find the most elegant solutions, rather than simply the most practical solutions. "

"His favourite lectures were the theoretical ones2. He often went to the library to work on problems by himself - rather than simply finding the most practical solutions, he aimed to find the most elegant solutions. "

Apart from that it is ready to go to the next stage

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### Subbing Paul Dirac

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