English

Existence of Approximately Macroscopically Unique States

Operator Algebras 2024-02-21 v1

Abstract

Let HH be an infinite dimensional separable Hilbert space and B(H)B(H) the C*-algebra of bounded operators on H.H. Suppose that T1,T2,...,TnT_1,T_2,..., T_n are self-adjoint operators in B(H).B(H). We show that, if commutators [Ti,Tj][T_i, T_j] are sufficiently small in norm, then ``Approximately Macroscopically Unique" states always exist for any values in a synthetic spectrum of the nn-tuple of self-adjoint operators. This is achieved under the circumstance for which the nn-tuple may not be approximated by commuting ones. This answers a question proposed by David Mumford for measurements in quantum theory. If commutators are not small in norm but small modulo compact operators, then ``Approximate Macroscopic Uniqueness" states also exist.

Keywords

Cite

@article{arxiv.2402.12609,
  title  = {Existence of Approximately Macroscopically Unique States},
  author = {Huaxin Lin},
  journal= {arXiv preprint arXiv:2402.12609},
  year   = {2024}
}
R2 v1 2026-06-28T14:53:53.502Z