November 30, 2018

Knot Shadow


Knot sculpture by Nat Friedman. Albany, New York, 2000.

The continuous loop of a three-dimensional mathematical knot constructed from copper tubing casts a shadow that can vary greatly in appearance and complexity, depending on the viewpoint and light direction.

Photo by I. Peterson

November 29, 2018

Ten Tetrahedra


Solar System by Eve Torrence. Exhibition of Mathematical Art, Joint Mathematics Meetings, San Francisco, California, 2010.

Photo by I. Peterson

November 28, 2018

November 27, 2018

Open House


Toronto, Ontario, 2015.

Photo by I. Peterson

November 26, 2018

November 25, 2018

Granny Pillow


Dihedral Granny Pillow by Andrea Heald. Gallery of Mathematical Art, Joint Mathematics Meetings, Boston, Massachusetts, 2012.

Photo by I. Peterson

November 24, 2018

Snow Soldier


Washington, D.C., 1982.

Photo by I. Peterson

November 23, 2018

Fractured Flower


Design by Antoni Gaudi. Parc Guell, Barcelona, Spain, 2007.


Photos by I. Peterson

November 22, 2018

Dinner Roses


Toronto, 2011.

Photo by I. Peterson

November 21, 2018

November 20, 2018

Deep Pink


Hawaii, 1983.

Photo by I. Peterson

November 19, 2018

Station Lights


Central Station, Milan, Italy, 2010.

Photo by I. Peterson

November 18, 2018

Vegemite Place


Jaisalmer India, 2010.

Photo by I. Peterson

November 17, 2018

Rudder Ice


Kingston, Ontario, 1974.

Photo by I. Peterson

November 16, 2018

Ptolemy and Regiomontanus



This frontispiece from Epitoma in Almagestum Ptolemaei, published in 1496, shows its author, Regiomontanus, and a crowned Ptolemy.

Reproduced from the collections of the Library of Congress.

November 15, 2018

Madison Glow


Wisconsin State Capitol, Madison, Wisconsin, 2008.

Photo by I. Peterson

November 14, 2018

Shore Splash


Ocean City, Maryland, 1979.

Photo by I. Peterson

November 13, 2018

November 12, 2018

Macdonald Chemistry


Macdonald Chemistry and Mining Building, McGill University, Montreal, Quebec, 2006.

Photo by I. Peterson

November 11, 2018

November 10, 2018

Model Surface


Mathematics Department, University of Nebraska, Lincoln, Nebraska, 2012.



Photos by I. Peterson

November 9, 2018

Brooklyn Bridge


Brooklyn Bridge, New York City, New York.

Photo by I. Peterson

November 8, 2018

Elements 29


Elements Number 29 by Siah Armajani. Sculpture Garden, New Orleans Museum of Art, New Orleans, Louisiana, 2010.

Photo by I. Peterson

November 7, 2018

Five Plates Two Poles


Five Plates, Two Poles by Richard Serra, East Building, National Gallery of Art, Washington, D.C., 2017.

See also "Three of Five."

Photo by I. Peterson

November 6, 2018

American Way


Wall mural, Washington, D.C., 2018.


Photos by I. Peterson

November 5, 2018

Forest Rainbow


Rainy River, Ontario, 1977.

Photo by I. Peterson

November 4, 2018

Fragments in Flight


Market Street, Philadelphia, 2000.


Photos by I. Peterson

November 3, 2018

November 2, 2018

Cathedral of Learning


Cathedral of Learning, University of Pittsburgh, Pittsburgh, Pennsylvania, 2010.

Photo by I. Peterson

November 1, 2018

Being Elderly


The Dignity of Being Elderly by Shirley Rush Dean. Bethesda, Maryland, 2018.

Photo by I. Peterson