The extras

Demos

• Cyclic Pianos (2026)
  Browser · no dependencies · works offline
  A playable keyboard whose keys are the vertices of a cycle or of a Möbius ladder, with anywhere up to 24 notes to the octave. The black-key set is chosen to minimise energy on the underlying graph, and the geometry of whatever you are playing is drawn live beside the keys. It will also read a MIDI file and play it back on the current tuning, naming the chords and scrolling the score as it goes.
• Cyclic Sequences (2026)
  Browser · no dependencies
  Companion page to the Bridges 2026 work: minimum-energy sets on cycles and Möbius ladders, and the sequences the keyboards are built from.
• Mathematical genealogy (2026)
  Browser · portraits from Wikipedia
  My advisor graph, back through Bollobás, Erdős, Fejér, Weierstraß and Gauß to seventeenth-century Leipzig. Click anyone to light up every path from them down to me. It is a graph and not a tree, which is the fun of it.

Exhibits

• Cyclic and Möbius Pianos (2026)
  Bridges 2026 Exhibition of Mathematical Art, Craft, and Design · University of Galway, Ireland
  3D-printed keyboards laid out on cycles and Möbius ladders.
• Alternative Pianos (2024)
  Bridges 2024 Exhibition of Mathematical Art, Craft, and Design · Richmond VA
  3D-printed keyboards built on cycles and Möbius ladders.

Math circles and family days

• Mathematical Rhythms (Aug 2026)
  Bridges 2026 Family Day · University of Galway, Ireland
  Four floating percussion panels, each playing the minimum-energy onset set on a cycle or a Möbius ladder. Drag the graph to change the number of pulses and strikes; pull the centre arc to rotate. Runs offline on a tablet.
• VCU Math Circle (2018–2022)
  Virginia Commonwealth University, Richmond VA
  Run for high school students. Sessions on percolation among zombies, and on mathematical music theory.
• ASU Math Circle (2015–2016)
  Arizona State University, Tempe AZ
  Run for high school students. Sessions on winning strategies, and on mad scientists, permutations and combinatorics.
• Sonya Kovalevsky Girls in Math Day (2017, 2018)
  Virginia Commonwealth University, Richmond VA
  Conway's rational tangles, for junior high and middle school students.
• Mathematics Awareness Day (2015, 2016)
  Arizona State University, Tempe AZ
  Workshops for high school students on the mathematics of billiards and reflections, and on Conway's rational tangles.

Special sessions organised

• Coloring Problems in Combinatorics (Jan 2025)
  AMS Special Session · Joint Mathematics Meetings, Seattle WA
• Topics in Combinatorics and Graph Theory (Jan 2024)
  AMS Special Session · Joint Mathematics Meetings, San Francisco CA · with Cory Palmer and Anastasia Halfpap
• Extremal Graph Theory (Apr 2023)
  AMS Special Session · Spring Central Sectional Meeting, University of Cincinnati · with Puck Rombach, Calum Buchanan and Victoria Bednar

Elsewhere

• Meet a student (2023)
  VCU Department of Mathematics and Statistics
  Somebody says something kind. Scroll down.

Genealogy

Data from the Mathematics Genealogy Project.

Links

Things I am interested in or find useful. I am in no way affiliated with any of these sites, and placement here should not be taken as any kind of endorsement.

Open source mathematics

• SageMath the free open-source mathematics system.
• CONJECTURING Nico Van Cleemput and Craig Larson's automated conjecturing program for Sage.
• OIP-GT Craig Larson's Objects, Invariants and Properties for Graph Theory.

Where I've studied and taught

• Silver Ridge Elementary School Silverdale WA.
• Central Kitsap Junior High School Silverdale WA; now Central Kitsap Middle School.
• Central Kitsap High School Silverdale WA.
• University of Colorado Boulder CO.
• University of Waikato Hamilton, New Zealand.
• Western Washington University Bellingham WA.
• University of Memphis Memphis TN.
• Instituto Nacional de Matemática Pura e Aplicada Rio de Janeiro.
• Arizona State University Tempe AZ.
• University of Vermont Burlington VT.
• Virginia Commonwealth University Richmond VA.