# Feature Column Authors

# The Archive

##
### 2019

You’re in for a shock by David Austin

December 2019 Why 95% ? by Bill Casselman

November 2019 Topological Quantum Field Theory for Vampires by Ursula Whitcher

October 2019 Pretty as a Picture (Part II) by Joe Malkevitch

September 2019 Puppies, Kittens, and the Golden Ratio by David Austin

August 2019 Understanding Kepler III–Predecessors by Bill Casselman

June 2019 Topology and Elementary Electric Circuit Theory, II: Duality by Tony Phillips

May 2019 Pretty as a Picture (Part I) by Joe Malkevitch

April 2019 Non-negative Matrix Factorizations by David Austin

March 2019 Understanding Kepler II–Earth’s Motion by Bill Casselman

February 2019 Branko Grunbaum Remembered–A Great Geometer! by Joe Malkevitch

January 2019

##
### 2018

Upgrading Slums Using Topology by David Austin

December 2018 Understanding What Kepler Did–Part I by Bill Casselman

November 2018 Topology and Elementary Electric Circuit Theory, I by Tony Phillips

October 2018 Recognition by Joe Malkevitch

September 2018 Getting in Sync by David Austin

August 2018 Reading the Bakhshali Manuscript by Bill Casselman

June 2018 Crochet Topology by Moira Chas

May 2018 Mathematical Economics for Mathematics and Statistics Awareness Month by Joe Malkevitch

April 2018 Neural Nets and How They Learn by David Austin

March 2018 Jakob Bernoulli’s Zoo by Bill Casselman

February 2018 Regular-Faced Polyhedra: Remembering Norman Johnson by Joe Malkevitch

January 2018

##
### 2017

How to Differentiate with a Computer by David Austin

December 2017 Solar Daze by Bill Casselman

November 2017 The Early History of Calculus Problems, II by Tony Phillips

October 2017 Ranking, Grading, and Genealogy by Joe Malkevitch

September 2017 Untangling Your Square Dance by David Austin

August 2017 The Joy of Barycentric Subdivision by Bill Casselman

June 2017 Surface Topology in Bach Canons, II: The Torus by Tony Phillips

May 2017 Remembering Bill Thurston (1946-2012) by Joe Malkevitch

April 2017 Patterns in Permutations by David Austin

March 2017 Assembly Required by Bill Casselman

February 2017 Building Trees for Biologists by Joe Malkevitch

January 2017

##
### 2016

Finding Holes in the Data by David Austin

December 2016 Circles and Squares … and Primes by Bill Casselman

November 2016 Surface Topology in Bach Canons, I: The Mobius strip by Tony Phillips

October 2016 Theoretical Mathematics Finds Use in Economics–A Tribute to Lloyd Shapley by Joe Malkevitch

September 2016 Game. SET. Polynomial. by David Austin

August 2016 The Legend of Abraham Wald by Bill Casselman

June 2016 The Early History of Calculus Problems by Tony Phillips

May 2016 Mathematics and Crystal Balls by Joe Malkevitch

April 2016 Knot Quandaries Quelled by Quandles by David Austin

March 2016 It Just Keeps Piling Up! by Bill Casselman

February 2016 Are Precise Definitions a Good Idea? by Joe Malkevitch

January 2016

##
### 2015

Petals, Flowers and Circle Packings by David Austin

December 2015 Circles and Squares by Bill Casselman

November 2015 Hidden Symmetries of Labyrinths from Antiquity and the Middle Ages by Tony Phillips

October 2015 Mathematics and Ecology by Joe Malkevitch

September 2015 Game. SET. Line. by David Austin

August 2015 Sums and Integrals: The Swiss analysis knife by Bill Casselman

June 2015 Math and the Sewing Machine by Tony Phillips

May 2015 Mathematical Careers by Joe Malkevitch

April 2015 The Stable Marriage Problem and School Choice by David Austin

March 2015 The Mathematics of the Rainbow, Part II by Bill Casselman

February 2015 Mathematics and Psychology by Joe Malkevitch

January 2015

##
### 2014

How to Grow and Prune a Classification Tree by David Austin

December 2014 Why Do We Expect Lots of Twin Primes? by Bill Casselman

November 2014 The Topology of Impossible Spaces by Tony Phillips

October 2014 Mathematics and Chemistry: Partners in Understanding Our World by Joe Malkevitch

September 2014 Congressional Redistricting and Gerrymandering by David Austin

August 2014 Feeling Your Way Around in High Dimensions by Bill Casselman

June 2014 The Knots in the Quipu, and in the Friar’s Belt by Tony Phillips

May 2014 Magical Mathematics – A Tribute to Martin Gardner by Joe Malkevitch

April 2014 How to Make a 3D Print by David Austin

March 2014 Stereographic Projection by Bill Casselman

February 2014 Periods by Joe Malkevitch

January 2014

##
### 2013

The Polish Attack on Enigma II: Zygalski sheets by Bill Casselman

December 2013 Fedorov’s Five Parallelohedra by David Austin

November 2013 Spherical Dodecahedral Space by Tony Phillips

October 2013 Words and More Words by Joe Malkevitch

September 2013 The Frobenius Problem: How I bought Chicken McNuggets with exact change by David Austin

August 2013 More ENIGMA by Bill Casselman

June 2013 Galileo’s Arithmetic by Tony Phillips

May 2013 Sustainability by Joe Malkevitch

April 2013 Using Projective Geometry to Correct a Camera by David Austin

March 2013 How to Read QR Symbols Without Your Mobile Telephone by Bill Casselman

February 2013 Hurricane Sandy Meets Mathematics by Joe Malkevitch

January 2013

##
### 2012

Who’s Number 1? Hodge Theory Will Tell Us by David Austin

December 2012 Can You Do Better? by Bill Casselman

November 2012 William Thurston by Tony Phillips

October 2012 Mathematical Modeling by Joe Malkevitch

September 2012 It’s a Small World After All by David Austin

August 2012 What Does a Circle Look Like? by Bill Casselman

June 2012 Old Babylonian Multiplication and Reciprocal Tables by Tony Phillips

May 2012 More Precious than Gold? by Joe Malkevitch

April 2012 A (Very Short) Detour for the Traveling Salesman by David Austin

March 2012 Archimedes on the Circumference and Area of a Circle by Bill Casselman

February 2012 Weird Rulers by Joe Malkevitch

January 2012

##
### 2011

Arrangements and Duality or How I Learned to Slice a Ham and Cheese Sandwich by David Austin

December 2011 Fragments of Greek Mathematics by Bill Casselman

November 2011 X-ray Crystallography and the Fourier Transform by Tony Phillips

October 2011 Going, Going, …, Gone! by Joe Malkevitch

September 2011 The Shadow Knows: How to measure time with a sundial by David Austin

August 2011 What’s Normal? by Bill Casselman

June 2011 How Not to Square the Circle by Tony Phillips

May 2011 Complexity by Joe Malkevitch

April 2011 Aligning Sequence Reads to Assemble the Genome Puzzle by David Austin

March 2011 Why Only Five? by Bill Casselman

February 2011 The Price of Anarchy by Joe Malkevitch

January 2011

##
### 2010

How Many Times Do I Have to Shuffle This Deck? by David Austin

December 2010 Geometry and the Discrete Fourier Transform by Patrick Ion

November 2010 Farey Numbers and the Magnetic Cactus by Tony Phillips

October 2010 Who Won! by Joe Malkevitch

September 2010 Multiplication is Easier When It’s Complex by David Austin

August 2010 How Did Escher Do It? by Bill Casselman

June 2010 From Pascal’s Triangle to the Bell-shaped Curve by Tony Phillips

May 2010 Mathematics and Sports by Joe Malkevitch

April 2010 Moving Remy in Harmony: Pixar’s Use of Harmonic Functions by David Austin

March 2010 Crypto Graphics by Bill Casselman

February 2010 Keep on Trucking by Joe Malkevitch

January 2010

##
### 2009

Puzzling Over Exact Cover Problems by David Austin

December 2009 Marian Rejewski and the First Break into Enigma by Bill Casselman

November 2009 A Non-Commutative Marriage System in the South Pacific by Tony Phillips

October 2009 School Choice by Joe Malkevitch

September 2009 We Recommend a Singular Value Decomposition by David Austin

August 2009 How Much Longer Can This Go On? by Bill Casselman

June 2009 Simon Newcomb and “Natural Numbers” (Benford’s Law) by Tony Phillips

May 2009 Mathematics and Climate by Joe Malkevitch

April 2009 No Static at All: Frequency modulation and music synthesis by David Austin

March 2009 The Mathematics of Rainbows by Bill Casselman

February 2009 People Making a Difference by Joe Malkevitch

January 2009

##
### 2008

“Trees, Teeth, and Time: The mathematics of clock making by David Austin

December 2008 From Bézier to Bernstein by Bill Casselman

November 2008 Inside-out Frieze Symmetries in Ancient Peruvian Weavings by Tony Phillips

October 2008 Gray Codes by Joe Malkevitch

September 2008 Percolation: Slipping through the Cracks by David Austin

August 2008 The Mathematics of Surveying: Part II. The Planimeter by Bill Casselman, John Eggers

June 2008 The Mathematics of Surveying: Part I by Tony Phillips

May 2008 The Process of Electing a President by Joe Malkevitch

April 2008 Random Numbers: Nothing Left to Chance by David Austin

March 2008 What is the Length of a Year on Planet Sitnikov? by Bill Casselman

February 2008 Urban Geometry by Joe Malkevitch

January 2008

##
### 2007

Pulling Digits out of Pi by David Austin

December 2007 Strange Associations by Bill Casselman

November 2007 Taxi! by Joe Malkevitch

October 2007 Image Compression: Seeing What’s Not There by David Austin

September 2007 Time and the Hour Running Through Rough Days by Bill Casselman

August 2007 The Mathematics Behind Quantum Computing: Part II by Tony Phillips

June 2007 The Mathematics Behind Quantum Computing: Part I by Tony Phillips

May 2007 Mathematics and the Brain by Joe Malkevitch

April 2007 That Knotty DNA by David Austin

March 2007 All for Nought by Bill Casselman

February 2007 Rationality and Game Theory by Joe Malkevitch

January 2007

##
### 2006

How Google Finds Your Needle in the Web’s Haystack by David Austin

December 2006 Lorenz and Modular Flows: A Visual Introduction by Étienne Ghys, Jos Leys

November 2006 The Princess of Polytopia: Alicia Boole Stott and the 120-cell by Tony Phillips

October 2006 Finite Geometries? by Joe Malkevitch

September 2006 Voronoi Diagrams and a Day at the Beach by David Austin

August 2006 Simple Chaos – The Hénon map by Bill Casselman

June 2006 The Octosphericon and the Cretan Maze by Tony Phillips

May 2006 Mathematics and Internet Security by Joe Malkevitch

April 2006 When Kissing Involves Trigonometry by David Austin

March 2006 Variations on Graph Minor by Bill Casselman

February 2006 Trees: A Mathematical Tool for All Seasons by Joe Malkevitch

January 2006

##
### 2005

Penrose Tilings Tied up in Ribbons by David Austin

December 2005 The Mathematical Uncertainty Principle by Tony Phillips

November 2005 Mental Calculation by Bill Casselman

October 2005 Sales and Chips by Joe Malkevitch

September 2005 Penrose Tiles Talk Across Miles by David Austin

August 2005 Topology of Venn Diagrams by Tony Phillips

June 2005 Slingshots and Space Shots by Bill Casselman

May 2005 Mathematics and Cosmology by Joe Malkevitch

April 2005 Resolving Bankruptcy Claims by Joe Malkevitch

March 2005 The Center of Population of the United States by David Austin

February 2005 Euler’s Polyhedral Formula: Part II by Joe Malkevitch

January 2005

##
### 2004

Euler’s Polyhedral Formula by Joe Malkevitch

December 2004 Mathematical Marriages by Joe Malkevitch

November 2004 Voting Games: Part II by Joe Malkevitch

October 2004 Voting Games: Part I by Joe Malkevitch

September 2004 Machine Scheduling by Joe Malkevitch

August 2004 Bin Packing and Machine Scheduling by Joe Malkevitch

June 2004 Bin Packing by Joe Malkevitch

May 2004 Networks by Joe Malkevitch

April 2004 Diagonals: Part II by Joe Malkevitch

March 2004 Diagonals: Part I by Joe Malkevitch

February 2004 Cubes by Joe Malkevitch

January 2004

##
### 2003

Colorful Mathematics: Part IV by Joe Malkevitch

December 2003 Colorful Mathematics: Part III by Joe Malkevitch

November 2003 Colorful Mathematics: Part II by Joe Malkevitch

October 2003 Colorful Mathematics: Part I by Joe Malkevitch

September 2003 A Discrete Geometrical Gem by Joe Malkevitch

August 2003 Primes by Joe Malkevitch

June 2003 Oriented Matroids: The Power of Unification by Joe Malkevitch

May 2003 Mathematics and Art by Joe Malkevitch

April 2003 Combinatorial Games (Part II) -Different Moves for Left and Right by Joe Malkevitch

March 2003 Digital Revolution (III) – Error Correction Codes by Joe Malkevitch

February 2003 Matroids: The Value of Abstraction by Joe Malkevitch

January 2003

##
### 2002

Combinatorial Games (Part I): The World of Piles of Stones by Joe Malkevitch

December 2002 Linkages (Part II) – Old Wine in New Bottles by Joe Malkevitch

November 2002 October: Digital Revolution (II) – Compression Codes and Technologies by Joe Malkevitch

October 2002 September: Linkages: From Fingers to Robot Arms (I) Introduction by Joe Malkevitch

September 2002 July/August: The Digital Revolution (I) – Barcodes: Introduction by Joe Malkevitch

August 2002 Apportionment II by Joe Malkevitch

June 2002 Apportionment I by Joe Malkevitch

May 2002 Mathematics and the Genome by Joe Malkevitch

April 2002 Voting and Elections by Joe Malkevitch

March 2002 Nets: A Tool for Representing Polyhedra in Two Dimensions by Joe Malkevitch

February 2002 Alberti’s Perspective Construction by Tony Phillips

January 2002

##
### 2001

Topology and Verb Classes by Tony Phillips

December 2001 Finite-dimensional Feynman Diagrams by Tony Phillips

November 2001 The Romance of Double-Entry Bookkeeping by Tony Phillips

October 2001 Latin Squares in Practice and in Theory II by Tony Phillips

September 2001 Latin Squares in Practice and in Theory I by Tony Phillips

August 2001 Fourier Analysis of Ocean Tides III by Tony Phillips

June 2001 Fourier Analysis of Ocean Tides II by Tony Phillips

May 2001 Fourier Analysis of Ocean Tides I by Tony Phillips

April 2001 A New Solution to the Three Body Problem – And More by Bill Casselman

March 2001 The Mathematical Study of Mollusk Shells by Tony Phillips

February 2001 Celestial Mechanics on a Graphing Calculator by Tony Phillips

January 2001

##
### 2000

Packing Pennies in the Plane by Bill Casselman

December 2000 The Mathematics of Communication by Tony Phillips

November 2000 Mathematical Card Tricks by Colm Mulcahy

October 2000 The Mathematics of Piano Tuning by Tony Phillips

September 2000 Navigational Mathematics by Tony Phillips

August 2000 The Catastrophe Machine by Tony Phillips

June 2000 Visual Explanations in Mathematics by Tony Phillips

March 2000 The ABC of DNA Computing by Tony Phillips

February 2000 The Method of Archimedes by Tony Phillips

January 2000

##
### 1999

The Mathematical CAT scan by Tony Phillips

December 1999 Metonymy and Metaphor in Mathematics by Tony Phillips

November 1999 The Differential Geometry of the Sphericon by Tony Phillips

October 1999 Descartes’ Lost Theorem by Tony Phillips

September 1999 The Most Irrational Number by Tony Phillips

August 1999 Multiple Mathematical Intelligences by Tony Phillips

June 1999 From Euclid and Euler to Public-key Codes by Tony Phillips

May 1999 Knots and their Polynomials by Tony Phillips

April 1999 Math and the Musical Offering by Tony Phillips

March 1999 Gravitational Lensing and Geometric Lensing by Tony Phillips

February 1999 A Prime Case of Chaos by Steve Weintraub

January 1999

##
### 1998

Calculating Pi using Elementary Calculus by Steve Weintraub

December 1998 Factorization–Unique and Otherwise by Steve Weintraub

November 1998 André Weil, May 6, 1906-August 6, 1998 by Steve Weintraub

October 1998 Prize Winners at the 1998 International Congress of Mathematicians by Steve Weintraub

September 1998 Polyhedra by Steve Weintraub

August 1998 Turing Machines by Steve Weintraub

July 1998 “The Trigonometry of Escher’s Woodcut “Circle Limit III” by Steve Weintraub

June 1998 Newton Basins by Steve Weintraub

May 1998 Quadric Surfaces by Steve Weintraub

April 1998 1998 Mathematics Awareness Week by Steve Weintraub

March 1998 Tiling the Poincaré Disk by Steve Weintraub

February 1998 The Mathematics Behind the Nobel Prize in Economics by Steve Weintraub

January 1998

##
### 1997

G. H. Hardy (1877-1947) by Steve Weintraub

December 1997 Fourier Approximation by Steve Weintraub

November 1997 J. J. Sylvester (1814-1897) by Steve Weintraub

October 1997 An Aperiodic Tiling by Steve Weintraub

September 1997 Pathfinder pictures from Mars by Steve Weintraub

August 1997 Mathematical Insights for Medical Imaging by Steve Weintraub

July 1997 You Can’t Always Hear the Shape of a Drum by Steve Weintraub

June 1997 A Wallpaper Pattern by Steve Weintraub

May 1997 Hyperbolic Space Tiled by Dodecahedra, 1 by Steve Weintraub

April 1997 Mathematics Awareness Week 1997 by Steve Weintraub

March 1997 The Unknotting Number of a Knot by Steve Weintraub

February 1997