Home- Larry Musa

Merry Christmas 2025

Celebrating the holiday season with reflections on physics, mathematics, and computer science.

Christopher Columbus

October 9, 2023
Remembering and honoring the great explorer...

Happy Columbus Day!

Thoughts on the AP Calculus Exam

Without the invention of the infinitesimal calculus, most of our technology would have been impossible. Should we therefore say that calculus is bad?
-- Stanisław Ulam

Einstein, Born, and Inflation

Inflation is taxation without representation.
-- Milton Friedman

We Remember

September 11, 2021

Lev Landau and Math Education

In nature's infinite book of secrecy
A little I can read.

-- Shakespeare

TJHS, Satellites, and the Asian Quota

MERIT
n.
Superior quality or worth; excellence.
n.
A quality deserving praise or approval; virtue.

Thanksgiving 2020

Happy Thanksgiving!

Robert Heinlein, Logs and Voting

We Will Never Forget

The Day Before

Happy 4th of July!

Merry Christmas!

Roy Glauber

Quantum computing and photon interference

The Monkey Shakespeare Probability

I cannot do't without counters

- Shakespeare

Israel Issac Rabi

What's in a name?
That which we call a rose
By any other name
Would smell as sweet.

- Shakespeare

John C Reynolds

The ideas of contravariance, and covariance, long of great utility in physics, were introduced into C# beginning with .Net Framework 3.5... At first glance there seems to be no relation between the physics and computer science usages...It might therefore be of interest to show the history of these ideas and how they found their way into the theory of computer languages...

Charles Townes

The great Charles Townes (7/28/1915 - 1/27/2015) inventor of the maser/laser, celebrates a birthday this week.

Pyotr Ufimtsev

When I was a kid, we had a neighbor whose job it was to translate Russian literature. This seemed to me at the time to be a rather peculiar job. German and French, sure, but Russian was not particularly popular. Why Russian? In retrospect, given that this was during the time of the cold war between the US and the USSR, it should have been obvious...

To Russia with Elton, 40 Years On

In keeping with the Russian/Ukrainian motif of the last two articles, here is a look back at Elton John's historic 1979 tour of Russia.

The Scottish Cafe

AS an undergraduate mathematics student, I had a topology professor who would tell his students about the early days of topology. There was it seemed a cafe where the Polish mathematicians would congregate and discuss mathematics for hours on end.

When some mathematician stumbled upon a problem or conjecture that was interesting but he could not solve, he could ask the coffee house staff for a book that was kept there just for the mathematicians...and in which the problem would be recorded as a challenge for any mathematician who visited the coffee house. From this cafe sprung many of the early results of topology and measure theory, and the book became rather famous, at least among topologists...

Well, it's a rather romantic story, but one that students tend to put aside as they concentrate on the job of actually learning the subject of topology!

But fast forward to the present -- and that cafe is now a bank...and that part of Poland is now Ukraine, and the Polish city of Lwow where the coffee house was located is now the Ukrainian city of Lviv ( "Lvov/Lviv translated from Russian/Ukrainian means "Lion". By the way, if you visit Lviv, you will discover many wonderful statues and sculptures, some quite old, of lions.)

Having visited Lviv a few times I have tended to concentrate on exploring the usual tourist attractions...but on a recent visit, I had to see if I could find this Scottish Cafe....

Richard Feynman, Corrected

A while ago, Vladimir Putin was shown on Russian television cavorting around Kyzyl, Tuva. (The same Tuva after which Microsoft named its excellent Tuva Project). Tuva was made famous in the physics world in 1991 by the publication of "Tuva or Bust, Richard Feynman's Last Journey"... At the time, the Tuva media attention caused me to dust off and re-read that book...leading, interestingly enough, to the discovery of a previously unknown, but unfortunately somewhat widely propagated, Feynman error. Yeah, Feynman published an error. So here is the story, along with my correction...

Hamilton

Recently, I talked to somebody who mentioned they had worked with coordinate systems and gimbals, which reminded me I have a backlog of old blog entries that have not been ported to .Net core... Here then is the port of an old post, on the great William Rowan Hamilton, quaternions, and gimbal lock...