We study a many-body ground state of graphene in perpendicular magnetic
fields. Chiral symmetry in graphene enables us to determine the many-body
ground state, which turns out to be a doubly degenerate chiral condensate for
the half-filled (undoped) case. In the ground state a prominent charge
accumulation emerges along zigzag edges. We also show that gapless excitations
are absent despite the presence of the robust edge modes, which is consistent
with the Chern number C = 0.Comment: 4 pages, 3 figures, proceeding of 26th International Conference on
Low Temperature Physics (LT26