On the Steinberg's Conjecture: 3-coloring of planar graphs

SIAM Student Seminar
Friday, April 1, 2011 - 1:00pm
1 hour (actually 50 minutes)
Skiles 246
School of Mathematics, Georgia Tech
Steinberg's Conjecture states that any planar graph without cycles of length four or five is three colorable. Borodin, Glebov, Montassier, and Raspaud showed that planar graphs without cycles of length four, five, or seven are three colorable and Borodin and Glebov showed that planar graphs without five cycles or triangles at distance at most two apart are three colorable. We prove a statement similar to both of these results: that any planar graph with no cycles of length four through six or cycles of length seven with incident triangles distance exactly two apart are three colorable. Special thanks to Robin Thomas for substantial contributions in the development of the proof.