Two-State Spin System graph G=(V,目 2 states {0,1) configuration o:V→{0，l} A [-月 b=(b0,b1)=(入，1) w(o）=ΠAa,o(o)IIb() (u,v)∈E v∈V edge activity: external field: λ○ 01Two-State Spin System A = ￾ A0,0 A0,1 A1,0 A1,1 ￾ = ￾ ￾ 1 1 ￾ ￾ 2 states {0,1} configuration ￾ : V ￾ {0, 1} graph G=(V,E) edge activity: ￾ ￾ 1 external field: ￾ 1 b = (b0, b1)=(￾, 1) w(￾) = ￾ (u,v)￾E A￾(u),￾(v) ￾ v￾V b￾(v)