Amina Buhler-Allen (with Marc Pelletier)
Stainless steel | 60 in diameter | 998 welded elements

The 120-cell, also known as the four-dimensional dodecahedron, is a mathematical form of exceptional complexity and beauty. As one of only six regular convex four-dimensional polytopes, it is composed of 120 dodecahedral cells arranged in perfect symmetry, a structure that has fascinated geometers for over a century.

First described by Swiss mathematician Ludwig Schläfli in the mid-19th century, the 120-cell extends the tradition of Platonic solids into a fourth spatial dimension. Because this object cannot exist physically in our three-dimensional world, mathematicians and model makers have historically created projections or physical approximations to help visualize it. Early representations were shown in public exhibitions and found homes in scientific collections such as the Franklin Institute.

The 120-cell and related structures have been referenced in the mathematical literature on symmetry and higher-dimensional forms, including works by Doris Schattschneider, a noted author and scholar of mathematical art and symmetry.

This sculpture was originally conceived by mathematician Marc Pelletier and later refined and brought into physical form by Amina Buhler-Allen, whose practice bridges advanced mathematics and sculpture. Fabricated with 998 precision steel elements and double TIG welded, the piece required craft beyond ordinary welding, with each element engineered to exact tolerances.

It was commissioned by Nobel laureate Sir Roger Penrose for installation at the University of Oxford. Institutional changes upon completion prevented its installation, and the sculpture remained crated for several years before arriving at The Sun ATL, where it now enters public view.

Penrose has described the sculpture as “the most beautiful object that I know of.”