4 papers
quant-ph2026
Sharp Entropy Cost of Coherent Leakage Across a Block Decomposition
Hassan Nasreddine
Let and let be the two-block pinching of a density matrix. Write , , and . We study the block-…
quant-ph2026
Entropy Moduli and Support-Sensitive BKM Coercivity for Rank-Deficient Non-Commutative Markov Semigroups
Hassan Nasreddine
We study entropy--coherence relations near rank-deficient support boundaries in finite-dimensional quantum systems. For block-diagonal reference states, we establish support-sensit…
quant-ph2026
Essential Duality and Quantitative Channel Composability in Algebraic Quantum Field Theory
Hassan Nasreddine
Let \(O\mapsto A(O)\) be a local Haag--Kastler net and let \(A^d(O)=A(O')'\) be its dual net. Normal unital completely positive maps on \(B(H)\) that fix \(A(O')\) pointwise are ex…
quant-ph2026
Quadratic Stability of Entropy Minimizers under Block-Separable Convex Constraints
Hassan Nasreddine
We investigate entropy minimization problems for quantum states subject to convex block-separable constraints. Our principal result is a quantitative stability theorem: under a nat…