The contents of this weblog have now been copied to …
Please use this instead of the octad.us URL.
A weblog on finite geometry, etc.
The contents of this weblog have now been copied to …
Please use this instead of the octad.us URL.
From Zenodo —
The mathematical discipline known as finite geometry was founded by Gino Fano in 1892. In 1962, Hans Freudenthal said of the axiomatic approach used by Fano (and later by Hilbert), “The bond with reality is cut.” The diamond theorem may be viewed as restoring that bond. It describes a group of 322,560 permutations, later known as “the octad group,” that now plays a role in speculative high-energy physics. See Moonshine, Superconformal Symmetry, and Quantum Error Correction .
The document below reproduces a statement, by Steven H. Cullinane, of the diamond theorem that has been in the online Encyclopedia of Mathematics since 10 May 2013.
Cullinane, Steven H. (2021).
“The Square Model of Fano’s 1892 Finite 3-Space.”
Zenodo. https://doi.org/10.5281/zenodo.4718182 .
Another online version of the square model of PG(3,2) —