## On Theory and Experiments

Regarding computing as a straightforward routine, some theoreticians still tend to underestimate its intellectual value and challenge, while practitioners often ignore its accuracy and overrate its validity.

C. K. Chu, Columbia University, 1978

## 2022

This semester we are continuing to perform research for DARPA on analytical methods for hypersonic aerodynamics. It is a difficult task. My new students are transitioning well and former students are excelling in their new careers. I am teaching a new course on turbulence modeling. This should be placed online for everyone near the end of the spring semester 2022.

## Foundations of Turbulence

The mathematical formulation of the problem of homogeneous turbulence is this: Given an infinite body of uniform fluid in which motions conform to the equations and, and given that at some initial instant the velocity of the fluid is a random function of position described by certain probability laws which are independent of position, to determine the probability laws that describe the motion of the fluid at subsequent times.

G. K. Batchelor in the Theory of Homogeneous Turbulence

## When2Meet – Wonderful App

https://www.when2meet.com/

Best little piece of software for finding mutual meeting times at work. Completely free and donation supported.

## On Nonsense

There is no reason to suppose that Carroll was in the slightest degree evasive in denying that he had intended his poem to mean anything at all. But, as he himself pointed out, words can mean much more than a writer intends. They can express meanings buried so deep in an author’s mind that he himself is not aware of them, and they can acquire meanings entirely by accident. Nonsense writing is a peculiarly rich medium for both types of “unintended” meaning.

Martin Gardner in the Hunting of the Snark

## Proof that Any Number Equals Itself from the Hunting of the Snark

$$\frac{(x+7+10)(1000-8)}{992}-17$$

## Calculator Museums

http://datamath.org/

There are a few wonderful websites online that show the history of calculators. I am very partial to Casio myself, but the Data Math Museum of Calculators has some very interesting history related to the TI series. Also, for those of you who grew up in the United States, one might remember the Little Professor calculator. This was often used by children for their first calculator. I had one as a kid and they are quite the collectors item today.

http://www.mrmartinweb.com/calculator.html

Another site, which is less TI focused, is Mr. Martin’s Calculator Museum website. Bonus in this site are links to particular slide rule and abacus related material.

## Quillbot – A Fast Writing Tool

https://quillbot.com/

Quillbot is a nice free (paid version available) tool to help rephrase or fix grammar issues in writing. Sometimes I encounter tough sentences when preparing papers. A quick copy and paste through Quillbot has helped. I also have referred to some of my students to the site. I do caution that sometimes the meaning of sentences or the technical message can be changed. Sometimes small word changes result in large changes in meaning or what we are trying to convey.