
Some memories from meeting Albert Einstein in 1951-52 - publisherad
http://cqgplus.com/2015/12/14/some-memories-from-meeting-einstein-in-1951-1952/
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scoot
_" When I told Lichnerowicz about Leray’s suggestion, he said “it is too
difficult for a beginner”. In fact it was not so difficult. In harmonic
coordinates, called then “isotherm”, introduced by Lanczos, DeDonder and
Georges Darmois, the Einstein equations in vacuum look like a system of
quasidiagonal, quasilinear system of second order partial differential
equations hyperbolic for a Lorentzian metric."_

There's beginner, and then there's 'beginner'.

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WalterBright
3 years of math at Caltech, and I'm dead in the water on what that means - I
don't even know the words, except that I know what second order partial
differential equations are.

~~~
kweinber
I had developed a truly marvelous explanation of that paragraph but I couldn't
fit it into the margin of this page.

~~~
theoh
It's probably not as complicated as it is being made to sound.

I don't know about the "quasis" but it sounds like a linear algebra problem.
Hyperbolic might be the form of the solutions to each of the differential
equations, or of their combined solution. "Lorentzian metric" presumably means
the usual Minkowski space of relativity.

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chmaynard
I loved reading this article. Yvonne Choquet-Bruhat's comments about the
mathematics of General Relativity were beyond my understanding, but there is
much to learn from her discussion of how her relationship with Einstein
developed.

If you want to explore this topic from another point of view, get to know the
work of Jeremy Bernstein, a theoretical physicist and long-time writer for The
New Yorker. Bernstein also spent some time at the IAS when he was a young
scientist, and has written a great deal about Einstein.

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noselfrighteous
I really love this story (no sarcasm intended at all). It's such a physicist's
story. The recollections of Einstein amount to "he was a nice guy", but the
bulk of the story is details about whatever problem she was working on at the
time.

