Talk:Paul Dirac

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Contents 1 What are they anyway? 2 External links 3 Dirac codec 4 Wigner 5 Pronunciation 6 Errors ID'd by Nature, to correct 7 Discovered ? 8 Views 9 Commemorative garden in St. Maurice 10 but/and 11 Atheist Citation?

[edit] What are they anyway?

Nature found 9 errors. You think they could tell us what they are so we can fix them? --24.63.36.180 18:14, 17 December 2005 (UTC)

[edit] External links

The external link page seems to have moved OK. I searched around a little and fixed it.

[edit] Dirac codec

The BBC has developed a video compression codec named after Dirac. http://www.theregister.co.uk/2004/05/10/bbc_develops_codec/ mparaz

[edit] Wigner

I got this from the wiginer article, "In Princeton in 1934 Wigner introduced his sister Manci to the physicist Paul Dirac. They married, and the ties between Wigner and Dirac deepened. Wigner also spent time with Einstein, who had come to Princeton to join the Institute For Advanced Study." However, in this article it claims it is Wiginer's daughter and a different name. Which is correct?

[edit] Pronunciation

How does one pronounce the name "Dirac"? --84.163.89.120 12:05, 13 July 2005 (UTC)

I can't vouch for the correct Swiss pronunciation, but physicists say "Dee-RAK." -- Eb.hoop 06:54, 14 July 2005 (UTC)

[edit] Errors ID'd by Nature, to correct

The results of what exactly Nature suggested should be corrected is out... italicize each bullet point once you make the correction. -- user:zanimum

• Dirac never worked as an engineer for a living (all he did was a few weeks’ research one summer, directly after his engineering degree).
• His PhD thesis did not mention Schrodinger’s quantum theory, so the characterization of Dirac’s early QM is not correct.
• Dirac first became interested in general relativity as a student in Bristol, not at Cambridge.
• His role in the discovery of field theory is not mentioned.
• Nor is his extremely important work in the least-action formulation of QM, now very important in modern field theory.
• I was surprised to see nothing at all about Dirac’s large number hypothesis (1937)
• Dirac did speak publicy about his early family life in his interview to the Archives of the History of Quantum Physics.
• He did not ‘derive’ the Dirac equation – he guessed it.
• He was not a committed atheist in later life. I’d describe him as agnostic.

I've gone ahead and fixed the errors identified. Someone else might want to add more about Dirac's role in the development of quantum field theory. -- Eb.hoop 21:31, 22 December 2005 (UTC)

It would be nice if Nature cited some verifiable sources for its factual statements and critiques:

• While it is nice to know that the unnamed Nature reviewer says, "I’d describe him as agnostic," I would much rather hear Dirac's own religeous views, to the extent that he stated them. Just my hunch: the reviewer is not, or at least prefers not to characterize him- or herself as, an athiest.
• Also, the criticism that Dirac "guessed" rather than "derived" his namesake equation is less than a quibble. Yes, I have read that he said that. However, unless one is attempting to describe Dirac's own perception of his internal mental process, the public is in no way misled by the statement that he "derived" it. Indeed "derived" may be the more accurate, objective description, given the constant subconscious mental processing that goes on in the minds mathematicians and other highly creative indivicuals.

I did not write either of these items into the Dirac article, so this is not self-justification. Finell (Talk) 22:39, 22 December 2005 (UTC)

I don't see the least-action stuff? William M. Connolley 21:18, 23 March 2006 (UTC)

Oops, as Aloan points out, its there under "path integral" William M. Connolley 17:56, 24 March 2006 (UTC)

[edit] Discovered ?

Has wikipedia standarized the term for discovering/developing mathematical objects ?. I think not all mathematicans agree that things are discovered, but rather think they are developed.

The question as to whether mathematics has any objective reality or whether it is just a construct of the human mind is an interesting philosohpical one. My POV is that, it depends on the maths: For example, if we imagine an alien race on the other side of the galaxy, they would have to know that the area of a circle = πr² if they were to make any progress with their crop circles. I'm sure we could recognise that part of their mathematics, if we saw it. That strongly implies that A = πr² exists out there and that intellects discover it.

However, I'm not so sure they would necessarily have a Dirac equation. They might have something similar that allowed them to model anti-particles but they wouldn't have anything familiar enough to our Dirac equation that we could immediately recognise it.

As an analogy, consider how it would work with technological objects: the aliens might have levers and gears but they probably wouldn't have a 4-cylinder, overhead-cam, 12-valve internal combustion engine. If you go along with that, then perhaps you'd have to say that Dirac invented his eponymous equation.--Oscar Bravo 13:50, 29 May 2006 (UTC)

[edit] Views

Removed: Dirac believed privately that God was a great mathematician. This underlied his belief that correct formulations of fundamental physical laws would be mathematically beautiful and simple.

A quick check on several physics biography websites revealed nothing like this about his "private" thoughts. If Xanaguy would like to produce an authoritative reference to the assertion, we can put it back in.--Oscar Bravo 13:50, 29 May 2006 (UTC)

[edit] Commemorative garden in St. Maurice

After visiting St. Maurice on a ski-trip in April 2006, I thought it worthwhile to add a sentence mentioning the commemorative garden there. My intial addition was:

A commemorative garden, in his honour, has been established opposite the railway station in Saint-Maurice, the town of birth of his father.

I was a bit surprised, however, by a line on the plaque which described Dirac as, "un originaire de Saint-Maurice". With my limited grasp of French, I took this to mean they were claiming he was born there, so I (unwisely!) added this line to the article:

Despite being born in Bristol, England of an English mother, the plaque in the garden rather cheekily describes him as originating in Saint-Maurice.

Of course, this started a chain of edits as various people pointed out that an originaire doesn't necessarily need to have been born in a certain place, and that parental lineage is sufficient. This is all very interesting but rather irrelevant to M. Dirac. So I removed the whole thing. If anyone is interested, apparently,

Under Swiss law, every child born to a father who is a Swiss national also has Swiss citizenship, in the case of Diracs, they are citizens of Saint-Maurice in Canton Valais. Since Paul Dirac's father, Charles, only renounced his Swiss citizenship in 1919, Paul also had Swiss citizenship until 1919, when he was 17.

--Oscar Bravo 07:43, 14 September 2006 (UTC)

[edit] but/and

I reverted Dirac became unsatisfied ... but his work on the subject moved increasingly out of the mainstream. to Dirac became unsatisfied ... and his work... for semantic reasons. The two clauses are in a causal relationship - because he became dissatisfied, his work moved out of the mainstream. So they should be connected with and (even and so!). Using but to connect the two implies that the second clause is in dissonance with the first, but it isn't... --Oscar Bravo 13:51, 20 September 2006 (UTC)

[edit] Atheist Citation?

I see this question was brought up once already, but are there any citations indicating Dirac was an atheist. I was actively looking for any information on his religious views, but I could not find much. The item that came up the most was this quote:

“God used beautiful mathematics in creating the world" [1]

Unless someone can provide good evidence for him being an atheist I think it should be removed. --Scott 00:33, 9 November 2006 (UTC)

Using Google I did mange to find this:

Brian, Denis (Editor). The Voice of Genius. Cambridge, Massachusetts: Perseus Publishing, 1995.

PAUL DIRAC (Nobel, physics, 1933) (Interview with his wife.)

What was your husband’s attitude toward religion?
He was a Christian. He went to church on Sundays.
You mean he believed in Jesus Christ?
Perhaps sometimes, and sometimes not. You know, most people are like that.
Most people I contacted are atheists.
My husband wasn’t an atheist
Did he feel there was an intelligent creator?
Yes, yes.

(P. 69)[2]

If anyone has the above mentioned book out there to confirm this, it should be case closed. --Scott 23:58, 26 November 2006 (UTC)