In a Nutshell:
The Seed
The Seed
"The symmetric group S6 of permutations of 6 objects is the only symmetric group with an outer automorphism….
This outer automorphism can be regarded as the seed from which grow about half of the sporadic simple groups…."
This "seed" may be pictured as
within what Burkard Polster has called "the smallest perfect universe"– PG(3,2), the projective 3-space over the 2-element field.
Related material: yesterday's entry for Sylvester's birthday.