Nayak's info.theo.argument x∈{0,1}n Index(x,i)=xi ie[n] Alice Px Bob ·p=∑xPxPx ·S(p)=S(2p0+2p1)∥p=2∑xx1=oPxPx I(X1,M1)+S(po)+7S(p) /Holevo bound.M1:Bob's conclusion about X1 ≥1-H(e)+hS(po)+S(p1)∥Fano's Inequ. ≥..≥n(1-H(e)Nayak’s info. theo. argument • ρ = ∑x px ∙ρx • S(ρ) = S(½ρ0+½ρ1 ) // ρb = 2 ∑x:x_1=b px ∙ρx ≥ I(X1 ,M1 ) + ½S(ρ0 )+½S(ρ1 ) // Holevo bound. M1 : Bob’s conclusion about X1 ≥ 1 – H(ε) + ½S(ρ0 )+½S(ρ1 ) // Fano’s Inequ. ≥ … ≥ n(1 – H(ε)). Alice Bob x{0,1}n i[n] Index(x,i) = xi ρx