Abstract
We investigate the statistical behavior of the eigenvalues and diameter of random Cayley graphs of SL2[Z/pZ] as the prime number p goes to infinity. We prove a density theorem for the number of exceptional eigenvalues of random Cayley graphs, i.e., the eigenvalues with absolute value bigger than the optimal spectral bound. Our numerical results suggest that random Cayley graphs of SL2[Z/pZ] and the explicit LPS Ramanujan projective graphs of P1(Z/pZ) have optimal spectral gap and diameter as the prime number p goes to infinity.
Original language | English (US) |
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Pages (from-to) | 328-341 |
Number of pages | 14 |
Journal | Experimental Mathematics |
Volume | 28 |
Issue number | 3 |
DOIs | |
State | Published - Jul 3 2019 |
All Science Journal Classification (ASJC) codes
- General Mathematics