Steve Trettel
Hello! I'm a mathematician and artist at the University of San Francisco, who works in geometry and mathematical visualization. This site collects my illustration, code, and writing. Sometimes I also take photographs and cook.
Art
Mathematical art that has been displayed in art shows, galleries, or museums.
Blog
Mostly notes to myself about things I'm trying to learn, or calculations from larger projects that may be interesting in their own right.
- Chemistry & Vibration Modes Apr 2026
- Curvature for Sphere Linkages Apr 2026
- Dynamics for Sphere Linkages Apr 2026
- Parameterizing Sphere Linkages Apr 2026
- Sphere Linkages Apr 2026
- Gauss' Linking Number IV Feb 2026
- Gauss' Linking Number III Feb 2026
- Gauss' Linking Number II Feb 2026
- Gauss' Linking Number I Feb 2026
- Limit Schottky Groups Nov 2025
Demos
Small web programs illustrating various mathematical objects, from both teaching and research.
Showing 8 of 372 demos Browse all →Graphics
An archive of mathematical illustrations I've made over the years.
Showing 8 of 290 graphics Browse all →Software
Larger systems and one-off tools, built mostly for research and teaching.
Projects
- constant-curvature-surfaces with Stepan Paul
- cubic-lines
- geodesic-boards with Edmund Harriss
- surfaces-of-revolution with Fabian Lander
- woven-surfaces with MPI Math Lab
Books & Course Notes
Long-form expositions, mostly notes from courses I've taught.
Modern Geometry
Notes / textbook for a 1 semester undergraduate course in geometry, taking calculus as the foundations. Covers Euclidean, Spherical and a bit of Hyperbolic geometry.
Multivariable Calculus
Supplementary Course Notes for the multivariable calculus course I teach at USF, with live animations.
Reaching for Infinity
A year-long advanced undergraduate real analysis textbook, with an emphasis on historically important problems.
Shaders
Course notes for GPU shader programming as a tool for mathematical visualization, covering fractals, implicit surfaces, tilings, and physical simulations in GLSL.
Websites
Project sites built for collaborations and research groups.
Algebraic Starscapes
Visualizing Elliptic Curves over Finite Fields
Geodesic Boards
Raymarching Thurston Geometries
This semester I am on sabbatical in Europe, and not teaching. (previous semesters)
- Fall 2026 Calculus I (MATH 109)
- Fall 2026 Differential Equations (MATH 340)
- Fall 2025 Linear Algebra (MATH 230)
- Fall 2025 Multivariable Calculus (MATH 211)
- Spring 2025 Multivariable Calculus (MATH 211)
- Spring 2025 Real Analysis (MATH 453)
- Fall 2024 Linear Algebra (MATH 229) — 2 sections
- Fall 2024 Multivariable Calculus (MATH 211)
- Spring 2024 Calculus I (MATH 109)
- Spring 2024 Real Analysis (MATH 453)
- Fall 2023 Multivariable Calculus (MATH 211)
- Fall 2023 Foundations of Geometry (MATH 380)
- Spring 2023 Real Analysis (MATH 453)
- Spring 2023 Multivariable Calculus (MATH 211)
- Fall 2022 Calculus I (MATH 109)
- Fall 2022 Calculus II (MATH 110)
When not at USF, I'm occasionally on the road for math — upcoming trips below, and where I've recently been. I particularly enjoy giving undergraduate colloquia and public lectures — if you'd like to have me visit, please get in touch.
- Apr 4 – Jun 18 Max Planck Institute for Mathematics in the Sciences Visiting Researcher Leipzig, Germany
- Jun 21–26 BIRS — Casa Matemática Oaxaca Frontiers in Surface Topology: Compact, Non-Compact, and Beyond Oaxaca, Mexico
- Jul 21–31 International Congress of Mathematicians Invited Mathematical Art Exhibition Philadelphia, PA
- Aug 5–8 MAA MathFest Invited Address Boston, MA
- Jan 18 – Apr 3 Institut Henri Poincaré Illustration as a Mathematical Research Technique (semester program) Paris, France
- Aug 11–15 ICERM — Illustrating Mathematics Speaker Providence, RI
- Jul 14–18 Bridges Math Art Conference Speaker Eindhoven, Netherlands
- May 25 – Jun 12 Max Planck Institute for Mathematics in the Sciences Visiting Researcher Leipzig, Germany
Recent Papers
- Classical Optics for Charged Black Holes Bridges Math Art 2025 Conference Proceedings, 2025
- Illustrating Hyperbolic Surfaces with Mesh Embeddings Bridges 2026, 2025
- Elliptic Curves and the Hopf Fibration Bridges Math Art Conference Proceedings, 2025, 2025
- Degenerations of the product geometries in projective space that contain Nil Topology and its Applications, 2024
- Visualizing Knot Complements MAA Focus, 2023
Recent Talks
- Visualizing Elliptic Curves over Finite Fields Institut Henri Poincare, 2026
- A Gravitational Photograph ICERM — Brown University, 2025
- Charged Black Holes TU Eindhoven, 2025
- 4d Knot Penn State — Student Colloquium, 2025
- Geometry of Graph Embeddings Penn State — Research Seminar, 2025