Sunday, September 29, 2024
Shaken, Not Stirred
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Annals of Snark: The Matchwood Patch
From The New York Times on Michaelmas 2024 —
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Saturday, September 28, 2024
For Michaelmas Eve —
Ex Fano Apollinis: All About Eve(s)
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Ex Fano Apollinis: All About Eve(s)
Ex Fano Apollinis: All About Eve(s)
Wednesday, September 25, 2024
Spell Casting —
“Miss Minutes” for a Jesuit
The Narnia Catechism: Is it Time Variants or Time Variance ?
Welcome to the Time Variance Authority!
Vide, from the above Jesuit date, the post
"Catchphrases from the city of Angels."
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“Miss Minutes” for a Jesuit
“Miss Minutes” for a Jesuit
Thursday, August 29, 2024
Fearful Symmetry
Peter Woit this afternoon on "The Terrifying Power of Mathematics" —
"… the quantum field theory of fields satisfying the Dirac equation.
Here there’s a standard apparatus of how to calculate given in
every quantum field theory textbook. These standard calculations
involving Dirac gamma-matrices fit well with Feynman’s 'physicists
finding they have the correct equations without understanding them
have been so terrified they give up trying to understand them'."
For a definition of these matrices, see . . .
Weisstein, Eric W. "Dirac Matrices."
From MathWorld — A Wolfram Web Resource.
https://mathworld.wolfram.com/DiracMatrices.html —
"The Dirac matrices are a class of 4×4 matrices which arise
in quantum electrodynamics. There are a variety of different
symbols used, and Dirac matrices are also known as
gamma matrices or Dirac gamma matrices."
For related religious remarks, see "Physics for Poets"
( Log24, April 20, 2022 ).
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Wednesday, June 21, 2006
Wednesday June 21, 2006
Go with the Flow
The previous entry links to a document that discusses the mathematical concept of "Ricci flow (pdf)."
Though the concept was not named for him, this seems as good a time as any to recall the virtues of St. Matteo Ricci, a Jesuit who died in Beijing on May 11, 1610. (The Church does not yet recognize him as a saint; so much the worse for the Church.)
There was no Log24 entry on Ricci's saint's day, May 11, this year, but an entry for 4:29 PM May 10, 2006, seems relevant, since Beijing is 12 hours ahead of my local (Eastern US) time.
The relevance of this structure
to memory and to Chinese culture
is given in Dragon School and in
Geometry of the 4x4x4 Cube.
For some related remarks on
the colloquial, rather than the
mathematical, concept of flow,
see
Philosophy, Religion, and Science
as well as Crystal and Dragon.
Yesterday's entry on the 1865
remarks on aesthetics of
Gerard Manley Hopkins,
who later became a Jesuit,
may also have some relevance.
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