University of Nebraska Kearney

         Quantum harmonic oscillator                           Among friends                                   

Barton Willis

Professor and Chair of the Department of Mathematics
2042 Founders Hall
University of Nebraska at Kearney
Kearney, NE 68849
willisb at unk dot edu

At UNK, I've taught college algebra (MATH 102), trigonometry (MATH 103), calculus (MATH 123, 115, 202, 260), foundations of mathematics (MATH 250), differential equations (MATH 305), linear algebra (MATH 440), numerical analysis (MATH 420), abstract algebra (MATH 350), complex analysis (MATH 365), and advanced calculus (MATH 460).

Computer Algebra 

I'm a developer for the Maxima computer algebra system. I wrote or co-authored Maxima packages for finite sets and combinatorics, linear algebra, orthogonal polynomials, Fourier elimination, hypergeometric functions, solving equations (to_poly_solver), Bernstein polynomials, and solutions to second order linear differential equations. Also, I wrote the code for the conjugate, floor, ceiling, mod, min, and max functions.   

In addition to teaching classes, I'm the chair of the department. For fun and relaxation, I program in Common Lisp; and when I can, I invent new mathematics.

Some Miscellaneous Things I have Written

• I don't gamble. Here is an essay I wrote about an article that was published in a mathematics journal on a scheme for placing bets on a horse race. The mathematics in the paper is correct, but it ignores the fact that the theory shows that the bets should really be negative! The journal published a retraction.
   
• Here are some slides (in postscript) for a talk I gave at a local MAA meeting on the condition number and numerical fuzz.
   
• Here are some slides for a talk I gave at a regional MAA meeting on the Maxima Computer Algebra Project.
   
• Here is my solution to problem 10795, ``Three-dimensional Lattice Walks in the Upper Half-Space,'' from the American Mathematical Monthly. Unlike the solution published in the December 2001 issue, my solution uses generating functions and Cauchy's integral formula.
   
• Here is an article that gives two methods for finding eigenvalues and eigenvectors without using determinants; and here are slides slides from a talk "A Determinatless Existence" I gave to faculty and students at UNK.
   
• Here is an essay I wrote for a calculus class about finite and infinite sums.
   
• And an essay about using set notation in undergraduate mathematics education. 

Biographical Sketch

I grew up on a hobby farm in the Kansas Flint Hills. For several years, I attended a two room grade school in Keats, Kansas. After graduation from Riley County High School, I earned a Bachelor of Science degree in Mathematics and Physics from Kansas State University. I studied mathematical physics at Virginia Tech, where I was a student of University Distinguished Professor Paul Zweifel and earned a Ph.D.

Nonacademic Things I Do

True to my hobby farm background, I enjoy digging up my yard and replacing the grass with flowers, vegetables, and berries. In my vegetable  garden, I grow collard greens, basil, tomatoes, onions, raspberries, lettuce, and peppers; in my flower gardens, favorites include Agastache, Aquilegia, Monarda, Penstemon, Rudbeckia, and Echinacea. Additionally, I've been lucky enough to grow an azalea in my alkaline soil.

I do volunteer gardening for a non-profit organization that is near my home. If you are starved for attention, try strolling through suburbia carrying garden implements.

I hike anywhere there are mountains and trees. I first visited Rocky Mountain National Park when I was four years old and I still love to hike there. I've climbed Mt. Handies (14,068 feet), Mt. Chiquita (13,069 feet), Hallet Peak (12,713 feet),  Mount LeConte  (6,593 feet), and Mount Rogers (5,729 feet), but mostly I like just being outside in nature.

A few years ago, I started taking art classes from a local artist. My Grandmother was an artist and my mother was a skilled crafts person, so maybe there is some hope for me.

I'm the founding member of the Kearney Introverts Club (KIC).  We don't have meetings or events. I know of two other members; everybody is welcome to join.

A few years ago, I acquired my first orchid. My beginners luck has faded, but I'm hooked nevertheless.