@inproceedings{Foundation2001VirtualQS,
title={Virtual Quantum Subsystems},
author={Paolo Zanardi Institute for Scientific Interchange Foundation and Istituto Nazionale per la Fisica della Materia},
year={2001}
}

The physical resources available to access and manipulate the degrees of freedom of a quantum system deﬁne the set A of operationally relevant observables. The algebraic structure of A selects a preferred tensor product structure i.e., a partition into subsystems. The notion of compoundness for quantum system is accordingly relativized. Universal control over virtual subsystems can be achieved by using quantum noncommutative holonomies

Although Bohr’s Correspondence Principle (CP) played a central role in the first versions of quantum mechanics, its original version seems to have no present-day relevance. The purpose of the present… Expand

Explicit construction of local observable algebras in quasi-Hermitian quantum theories is derived in both the tensor product model of locality and in models of free fermions. The latter construction… Expand

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Let us consider two qubits and the family by U λ := exp(i λ S) = cos λ 1 1 + i sin λ S where S |ψ ⊗ |φ = |φ ⊗ |ψ). If X1 := σx ⊗ 1 1 one has X1(U λ ) = cos 2 λ X1 + sin 2 λ 1 1 ⊗ σx + i

Phys

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) implies A2 ⊂ ⊕J Mn J (C) ⊗ 1 1 d J then A1 ∨ A2 = ⊕J Mn J (C) ⊗ M d J (C). A comparison of the dimension of this latter algebra