Basic Ring Theory Exam

Sections from Dummit & Foote being tested on the midterm:
  • §7.5 — 7.6
  • §8.1 — 8.3
  • §9.1 — 9.5
  • §10.1 — 10.3

Here are the midterm and final exams for Math 542, Modern Algebra, at the University of Wisconsin-Madison in the spring semester 2015-2016, Professor Paul Terwilliger officiating. It is an undergraduate class, junior or senior level, for (mostly) math majors. The class takes up basic ring theory, following on Math 541, which is mostly group theory. The text, followed pretty closely, is Abstract Algebra, 3rd ed., by David S. Dummit and Richard M. Foote (Wiley, 2004) — D&F — widely used it appears. It certainly is comprehensive, with many examples and a great set of exercises, and is an impressive work in its own right, well-organized, demanding, and thorough. Typo-free as well, I haven't found a single one.

Robert E. Lee Moore -- Topologist and Racist

 Robert E. Lee Moore
Robert E. Lee Moore (1882-1974)

It's a statement when someone names their child after Robert E. Lee, a man who did his best to destroy the United States in order to preserve slavery. Robert E. Lee was lionized more in death than in life, a paragon of the Lost Cause, the glorious if doomed rebellion of a brave people who wanted nothing but to be left alone, crushed by the soulless and brutal industrial juggernaut (Sherman's march to the Sea!). It's the big lie, forwarded for 150 years to defend the indefensible. What a wretched history of oppression, assiduously rebuilt over the generations by people like Moore, Sr. and his illustrious and vicious son Robert E. Lee Moore. The Compromise of 1877, peonage, disenfranchisement, lynching, Plessy v. Ferguson, Jim Crow, the Dunning school false flag on reconstruction. Read the old classics by W. E. B. Du Bois, Eric Foner, and C. Vann Woodward (himself a son of the south), among others, if you still doubt the long-standing construction and reconstruction of anti-black racism in this country down through the generations since 1865.

Keep Away Game in HTML5 Canvas

 Keep Away Game
Expand to entire article to play.

The Keep Away game was the last assignment in my Flash class and this is the port to HTML5 canvas, programmed in Javascript. Flash is declining for a number of reasons, including its proprietary nature and that it's not supported by the iPhone. Too bad, because Flash's ActionScript 3.0 is a thoroughgoing object oriented approach to graphics programming similar to Javascript. For the programmer, a circle or rectangle or any other figure suitable to be part of a display list is just an object with properties and methods. Many artists know Flash through the sophisticated Flash Pro environment, where they can create and store images efficiently with "symbols". Think Adobe Photoshop, apt in a couple ways considering that Adobe acquired Flash and developed ActionScript 3.0. Even animations are possible with "tweens". It's a nice in-between technology, where artists can experience Flash as as they always do, but be gently introduced to programming those objects in the code window. My approach is to forgo the environment entirely, except as a medium to execute ActionScript. The environment can be skipped entirely with Abobe's free compiler which turns ActionScript into .swf, which executes in the (free) Flash Player.

Teaching at MATC

 MATC circa 1912

After driving truck for eleven years, it was time for a change. Education was important in my household coming up. I have a Latin book from a great-great-grandfather on Mom's side. Half of Mom's family were teachers, including her parents for brief stints as young people in Iowa - two of my first cousins became Math and Computer Science professors in Canada. Mom did her entire high school through correspondence on the plains of Saskatchewan; she said trig just about sunk her. Dad too, where education was seen as a deliverance from poverty. He was an engineering student at the University of Manitoba and struggled through school for many years, having to support himself from a very young age. Struggled academically too, but was in awe of mathematics. I told him once as a kid I wanted to be an engineer like him; he said, oh no, shoot higher - go for mathematics. I still have his calculus book and gave his rebound copy of Men of Mathematics to my daughter Lydia when she graduated with a major in mathematics. On occasion I'd get some recognition at school, the honor roll or something, and would throw it aside as of little interest. Later it would appear framed and on the wall in Dad's home office. I essentially ended up teaching software engineering, that was typically my job title when working in the field; I think he would've been Ok with that.

High School English

 Jesuit High Dallas - 1943

I always laugh when people deprecate Catholicism as mindless superstition, because I know better from direct experience as a product of four years of Catholic high school. I started out at Jesuit High in Dallas in 1961. Mr. Joubert was my home room, religion, and English teacher. A lot of French names - it was the New Orleans Province after all, not missionaries from Chicago (like my grade school, St. Luke's in Irving). So a tip of the hat to Mr. Vavasseur, my sophomore geometry teacher, a tall, skinny, kind and intelligent man who knew and valued his subject and also knew how to transmit intellectual excitement. He was an important milestone in my mathematical education, especially considering that geometry is where students first encounter the axiomatic method and proofs, the cornerstones of modern mathematics. Between proofs, Mr Vavasseur regaled us with stories of how geometry had been the canonical science for two thousand years, even people like Spinoza modeling their philosophical speculations on Euclid. He quite rightly mentioned Giovanni Girolamo Saccheri, S. J., who foreshadowed non-Euclidean geometry. He was hell on wheels when crossed though; I remember him thundering more than once, "I'll be in Room 214 after school, Jones, be there" (emphasis on the last two words).


 August 2013 calendar

My original calendar program was on the Casio fx-3600p calculator in 1980 or so - my first programming venue and exercised partly in spare moments when driving truck out on the route; a precursor mobile device you could say. My buddy Dave got me started. I might have scarred myself permanently though. The transition from math to software engineering is always tricky, considering that there are many commonalities, but just as important differences to snag the self-taught and perhaps obstinate and all-too-confident mathematician (perish the thought). The 3600 had this bizarre little macro language providing for a trade-off between memory and program size. You could have (say) fifty memory locations and 400 instructions or twenty locations and 600 instructions. They're really variables of course, but the memory locations were designated K0 through K19 or something.

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