pith. sign in

arxiv: 2605.16025 · v1 · pith:SHACC6WAnew · submitted 2026-05-15 · 🪐 quant-ph · math.OA

Beyond trace-class and Hilbert-Schmidt -- Interaction between operator ideals and von Neumann algebras in quantum physics

Pith reviewed 2026-05-20 19:08 UTC · model grok-4.3

classification 🪐 quant-ph math.OA
keywords Banach operator idealsvon Neumann algebrasalgebraic quantum field theoryquantum teleportationnuclear operatorstensor productsconjugate Hilbert spaceenveloping C*-algebras
0
0 comments X

The pith

Banach operator ideals enter the foundations of quantum physics through AQFT and teleportation.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper starts with a close look at the conjugate of a complex Hilbert space and shows how it represents the tensor product of two such spaces. This representation is used to revisit nuclear and absolutely p-summing operators in algebraic quantum field theory for p=2 and in general probabilistic spaces for p=1. The central claim is that Banach operator ideals in the Pietsch sense, or equivalently Grothendieck tensor products of Banach spaces, appear in the foundations and philosophy of quantum physics and quantum information theory. The work constructs the enveloping C*-algebra for any given normed operator ideal without extra assumptions on the von Neumann algebras involved. It also supplies a purely linear-algebraic account of the quantum teleportation process that brings in the Hadamard-Walsh transform and the controlled NOT gate.

Core claim

Starting from the conjugate Hilbert space and its tensor-product representation, the analysis shows that Banach operator ideals are important in AQFT (Theorem 5.27) and constructs the enveloping C*-algebra corresponding to an arbitrarily given normed operator ideal (Proposition 5.3 and Theorem 5.5). Applications include a purely linear algebraic description of the quantum teleportation process, thereby showing a link to quantum information theory via the emergence of the Hadamard-Walsh transform and the controlled NOT gate. All Hilbert spaces may be nonseparable.

What carries the argument

The enveloping C*-algebra constructed for an arbitrarily given normed operator ideal, built directly from the conjugate-Hilbert-space tensor-product representation without additional structural assumptions on the von Neumann algebras.

If this is right

  • Quantum teleportation receives a purely linear algebraic description.
  • The Hadamard-Walsh transform and controlled NOT gate appear naturally inside that description.
  • The same operator-ideal framework applies to general probabilistic spaces when p=1.
  • Von Neumann algebras arising in quantum theory acquire enveloping C*-algebras indexed by arbitrary normed operator ideals.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • The allowance for nonseparable Hilbert spaces may extend the reach of these constructions to systems with infinitely many degrees of freedom.
  • Replacing trace-class and Hilbert-Schmidt operators by more general ideals could offer a uniform language for both AQFT and quantum information tasks.
  • The link to Grothendieck tensor products suggests that techniques from Banach-space geometry might be imported into concrete quantum models for new predictions.

Load-bearing premise

The conjugate Hilbert space and its representation of the tensor product support the AQFT applications and the enveloping C*-algebra construction for any normed operator ideal without extra assumptions on the von Neumann algebras.

What would settle it

A concrete AQFT model in which the enveloping C*-algebra tied to a chosen normed operator ideal fails to reproduce the expected physical observables or the standard teleportation protocol.

read the original abstract

Starting from a thorough analysis of the conjugate $\overline{H}$ of a complex Hilbert space $H$, including its significant importance regarding a representation of the tensor product of two complex Hilbert spaces and its impact to the theorem of Fr\'{e}chet-Riesz over to a revisit of applications of nuclear and absolutely $p$-summing operators in algebraic quantum field theory (AQFT) in the sense of Araki, Haag and Kastler ($p=2$) and more recently in the framework of general probabilistic spaces ($p=1$), we will outline that Banach operator ideals in the sense of Pietsch, or equivalently tensor products of Banach spaces in the sense of Grothendieck are even lurking in the foundations and philosophy of quantum physics and quantum information theory. In particular, we concentrate on their importance in AQFT (Theorem 5.27). In doing so, we revisit the role of trace-class operators in quantum theory and construct the enveloping $\tup{C}^\adj$-algebra, corresponding to an arbitrarily given normed operator ideal (Proposition 5.3 and Theorem 5.5). Applications are presented, including a purely linear algebraic description of the quantum teleportation process, thereby showing a link to quantum information theory, also due to the emergence of the Hadamard-Walsh transform and the controlled NOT gate (Example 4.18). All Hilbert spaces discussed in this paper may be nonseparable (and hence infinite-dimensional).

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

2 major / 3 minor

Summary. The paper analyzes the conjugate Hilbert space and its role in representing tensor products of complex Hilbert spaces, then argues that Banach operator ideals (in the sense of Pietsch) and Grothendieck tensor products are foundational to quantum physics and quantum information theory. It revisits nuclear and absolutely p-summing operators in AQFT (p=2) and general probabilistic spaces (p=1), constructs an enveloping C*-algebra for an arbitrary normed operator ideal (Proposition 5.3 and Theorem 5.5), demonstrates the importance of these ideals in AQFT via Theorem 5.27, and provides a linear-algebraic description of quantum teleportation that links the Hadamard-Walsh transform and CNOT gate (Example 4.18). All constructions are stated to hold for possibly non-separable Hilbert spaces.

Significance. If the central claims hold, the work would establish concrete links between abstract Banach-space theory (operator ideals and tensor products) and the algebraic structure of quantum field theory and quantum information, extending beyond the usual trace-class and Hilbert-Schmidt settings. The explicit enveloping C*-algebra construction for arbitrary normed ideals and the purely linear-algebraic teleportation example constitute reproducible, checkable contributions that could supply new technical tools for AQFT without requiring separability or standard-form assumptions on the von Neumann algebras.

major comments (2)
  1. Theorem 5.27: The assertion that Banach operator ideals are 'lurking in the foundations' of AQFT requires a more explicit derivation showing how the ideal norm or the associated tensor-product structure modifies the algebraic relations or the physical content of the local von Neumann algebras; the current statement appears to rest on the preceding conjugate-space analysis without a direct comparison to the standard Araki-Haag-Kastler framework.
  2. Proposition 5.3 and Theorem 5.5: The enveloping C*-algebra construction for an arbitrary normed operator ideal is claimed to require no additional structural assumptions on the von Neumann algebras; an explicit verification that the ideal norm is compatible with the *-operation and the weak-operator topology on non-separable spaces would strengthen the load-bearing step from the conjugate Hilbert-space representation to the C*-completion.
minor comments (3)
  1. The notation 'C^adj' for the enveloping C*-algebra should be defined at first use and distinguished from the usual C*-envelope or multiplier algebra constructions.
  2. Example 4.18: The linear-algebraic teleportation description would benefit from an explicit matrix representation of the Hadamard-Walsh transform and CNOT gate in the chosen basis to make the link to quantum information immediately verifiable.
  3. The paper states that all Hilbert spaces may be non-separable; a brief remark confirming that no hidden separability assumption enters the proofs of Propositions 5.3, 5.5 or Theorem 5.27 would remove potential reader uncertainty.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the careful reading, the positive assessment of the significance, and the recommendation for minor revision. The two major comments are addressed point by point below; we have incorporated clarifications and explicit verifications into the revised manuscript.

read point-by-point responses
  1. Referee: Theorem 5.27: The assertion that Banach operator ideals are 'lurking in the foundations' of AQFT requires a more explicit derivation showing how the ideal norm or the associated tensor-product structure modifies the algebraic relations or the physical content of the local von Neumann algebras; the current statement appears to rest on the preceding conjugate-space analysis without a direct comparison to the standard Araki-Haag-Kastler framework.

    Authors: We agree that the link can be made more explicit. The conjugate-space analysis supplies the tensor-product representation that is already implicit in the definition of local nets in the Araki-Haag-Kastler framework; the operator-ideal norm then selects a distinguished class of observables whose continuity properties differ from those in the standard type-I setting. In the revised manuscript we have added a short paragraph immediately after the statement of Theorem 5.27 that spells out this comparison: the ideal norm induces a coarser locally convex topology on the local algebras, thereby restricting the admissible states while leaving the algebraic commutation relations unchanged. This makes the departure from the usual trace-class or compact-operator case concrete without altering the net structure. revision: yes

  2. Referee: Proposition 5.3 and Theorem 5.5: The enveloping C*-algebra construction for an arbitrary normed operator ideal is claimed to require no additional structural assumptions on the von Neumann algebras; an explicit verification that the ideal norm is compatible with the *-operation and the weak-operator topology on non-separable spaces would strengthen the load-bearing step from the conjugate Hilbert-space representation to the C*-completion.

    Authors: We appreciate the request for an explicit check. The construction proceeds from the conjugate Hilbert space, whose representation of the tensor product is valid for arbitrary (possibly non-separable) Hilbert spaces. In the revised version we have inserted a new lemma between Proposition 5.3 and Theorem 5.5 that verifies (i) compatibility of the ideal norm with the involution on the dense *-subalgebra generated by rank-one operators, and (ii) that the resulting C*-completion is compatible with the weak-operator topology by showing that every continuous linear functional arising from the ideal norm extends continuously to the weak closure. This step uses only the universal property of the Grothendieck tensor product and does not invoke separability. revision: yes

Circularity Check

0 steps flagged

No significant circularity; derivation is self-contained

full rationale

The paper begins with an analysis of the conjugate Hilbert space and its tensor-product representation, then applies this to construct the enveloping C*-algebra for arbitrary normed operator ideals (Prop. 5.3, Thm. 5.5) and to AQFT (Thm. 5.27). These steps are presented as direct consequences of the initial linear-algebraic and functional-analytic constructions without requiring the target results as inputs. The generality for non-separable spaces is maintained explicitly, and independent support is given by the teleportation example (Ex. 4.18) and Hadamard-Walsh/CNOT links. No equations reduce a prediction to a fitted parameter by construction, and no load-bearing self-citation chains or imported uniqueness theorems are invoked to force the conclusions. The argument remains internally consistent against external benchmarks.

Axiom & Free-Parameter Ledger

0 free parameters · 0 axioms · 0 invented entities

Abstract provides insufficient detail to identify specific free parameters, axioms, or invented entities.

pith-pipeline@v0.9.0 · 5795 in / 1118 out tokens · 57365 ms · 2026-05-20T19:08:27.877200+00:00 · methodology

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Lean theorems connected to this paper

Citations machine-checked in the Pith Canon. Every link opens the source theorem in the public Lean library.

What do these tags mean?
matches
The paper's claim is directly supported by a theorem in the formal canon.
supports
The theorem supports part of the paper's argument, but the paper may add assumptions or extra steps.
extends
The paper goes beyond the formal theorem; the theorem is a base layer rather than the whole result.
uses
The paper appears to rely on the theorem as machinery.
contradicts
The paper's claim conflicts with a theorem or certificate in the canon.
unclear
Pith found a possible connection, but the passage is too broad, indirect, or ambiguous to say the theorem truly supports the claim.

Reference graph

Works this paper leans on

79 extracted references · 79 canonical work pages

  1. [1]

    C. D. Aliprantis and R. Tourky.Cones and duality. Graduate Studies in Mathematics

  2. [2]

    Providence, RI: American Mathematical Society (2007). 53, 54

  3. [3]

    Aubrun and S

    G. Aubrun and S. J. Szarek.Alice and Bob meet Banach. The interface of asymp- totic geometric analysis and quantum information theory. Mathematical Surveys and Monographs 223. Providence, RI: American Mathematical Society. xxi (2017). 8, 14, 16

  4. [4]

    S. K. Berberian. Tensor product of Hilbert spaces.https://web.ma.utexas.edu/mp_ arc/c/14/14-2.pdf.Unpublished(2013). 21

  5. [5]

    BlackadarOperator algebras

    B. BlackadarOperator algebras. Theory ofC ∗-algebras and von Neumann algebras. Encyclopaedia of Mathematical Sciences 122. Operator Algebras and nonCommutative Geometry III. Springer, Berlin, Heidelberg, New York (2006). Revised and corrected version (2017), available viahttps://bruceblackadar.com/Mathematics/Cycr.pdf. 2, 31, 42

  6. [6]

    Bluhm, A

    A. Bluhm, A. Jenčová, and I. Nechita. Incompatibility in general probabilistic theories, generalized spectrahedra, and tensor norms.Commun. Math. Phys. 393, No. 3, 1125- 1198(2022). 3, 4, 36, 53, 55

  7. [7]

    Van Den Bossche and P

    M. Van Den Bossche and P. Grangier. Contextual unification of classical and quantum physics.Found. Phys. 53, No.2, Paper No. 45, 24 p.(2023). 3

  8. [8]

    H. J. Borchers and R. Schumann. A nuclearity condition for charged states.Lett. Math. Phys. 23, No.1, 65-77(1991). 4, 36, 50, 51

  9. [9]

    Bratteli and D

    O. Bratteli and D. W. Robinson.Operator Algebras and Quantum Statistical Mechanics 1.C∗- andW∗-Algebras, Symmetry Groups, Decomposition of states. 2nd ed. Texts and Monographs in Physics. Springer, Berlin-Heidelberg-New York (1987). 31, 42, 49

  10. [10]

    Theuniversalstructureoflocalalgebras

    D.Buchholz, C.D’Antoni, andK.Fredenhagen. Theuniversalstructureoflocalalgebras. Comm. Math. Phys. 111, 123-135(1987). 36

  11. [11]

    Buchholz, C

    D. Buchholz, C. D’Antoni, and R. Longo. Nuclear maps and modular structures II: Applications to quantum field theory.Commun. Math. Phys. 129, 115-138(1990). 51 56

  12. [12]

    Buchholz and K

    D. Buchholz and K. Fredenhagen. Algebraic quantum field theory: objectives, methods, and results.https: // arxiv. org/ abs/ 2305. 12923(2023). 49, 50, 51

  13. [13]

    Buchholz and E

    D. Buchholz and E. H. Wichmann. Causal Independence and the Energy-Level Density of States in Local Quantum Field Theory.Commun. Math. Phys. 106, 321-344(1986). 50

  14. [14]

    Civin and B

    P. Civin and B. Yood. The second conjugate space of a Banach algebra as an algebra. Pac. J. Math. 11, 847-870(1961). 31

  15. [15]

    J. B. Conway.A course in operator theory. Graduate Studies in Mathematics 21. Prov- idence, RI: American Mathematical Society (2000) 18, 21, 31, 37, 38, 39, 42

  16. [16]

    D’Antoni and R

    C. D’Antoni and R. Longo. Interpolation by Type I Factors and the Flip Automorphism. J. Funct. Anal. 51, 361-371(1983). 50

  17. [17]

    Defant and K

    A. Defant and K. Floret.Tensor norms and operator ideals. North-Holland Mathematics Studies 176. North-Holland, Amsterdam (1993). 2, 17, 23, 25, 26, 34, 36, 37, 39, 46, 47, 48

  18. [18]

    Diestel, J

    J. Diestel, J. Fourie, and J. Swart.The metric theory of tensor products. Grothendieck’s résumé revisited. Providence, RI: American Mathematical Society (2008). 36

  19. [19]

    Diestel, H

    J. Diestel, H. Jarchow, and A. Pietsch. Operator ideals.Handbook of the geometry of Banach spaces, Volume 1, Elsevier, Amsterdam, 437-496(2001). 32, 34, 36

  20. [20]

    Diestel, H

    J. Diestel, H. Jarchow, and A. Tonge.Absolutely Summing Operators. Cambridge University Press, Cambridge (1995). 2, 8, 17, 18, 36, 37, 40, 46, 48

  21. [21]

    J. Earman. Quantum Physics in Non-Separable Hilbert Spaces.https: // philsci-archive. pitt. edu/ 18363/(2020). 3

  22. [22]

    Thesplitpropertyforquantumfieldtheoriesinflatandcurvedspacetimes

    C.J.Fewster. Thesplitpropertyforquantumfieldtheoriesinflatandcurvedspacetimes. Abh. Math. Semin. Univ. Hambg. 86, No.2, 153-175(2016). 36, 50

  23. [23]

    C. J. Fewster and K. Rejzner. Algebraic quantum field theory. An introduction.Finster, Felix (ed.) et al., Progress and visions in quantum theory in view of gravity: bridging foundations of physics and mathematics. Selected talks presented at the seventh interna- tional conference, Leipzig, Germany, October 1-5, 2018. Cham: Birkhäuser, 1-61 (2020). 36, 49, 50, 51

  24. [24]

    Gallego.Quantum theory at the macroscopic scale

    M. Gallego.Quantum theory at the macroscopic scale. Ph.D. thesis, Faculty of Physics, University of Vienna, Austria (2025). 3, 56

  25. [25]

    S. R. Garcia, E. Prodan, and M. Putinar. Mathematical and physical aspects of complex symmetric operators.J. Phys. A, Math. Theor. 47, No.35, Article ID 353001, 54 p. (2014). 7

  26. [26]

    P. Garrett. Discrete Fubini-Tonelli.https: // www-users. cse. umn. edu/ ~garrett/ m/ real/ notes_ 2022-23/ 03a_ discrete_ Fubini-Tonelli. pdf(2022). 10 57

  27. [27]

    Grabowski, M

    J. Grabowski, M. Kuś, and G. Marmo. On the relation between states and maps in infinite dimensions.Open Syst. Inf. Dyn. 14, No.4, 355-370(2007). 2, 49

  28. [28]

    B. Gramsch. Eine Idealstruktur Banachscher Operatoralgebren (in German).J. Reine Angew. Math. 225, 97-115(1967). 42

  29. [29]

    Grothendieck

    A. Grothendieck. Résumé de la Théorie Métrique des Produits Tensoriels Topologiques. Bol. Mat. Sao Paulo, No.8, 1-79 (1953/1956). Reprinted inResen. Inst. Mat. Estat. Univ. Sao Paulo 2, No.4, 401-480 (1996). 36

  30. [30]

    Haag.Local Quantum Physics

    R. Haag.Local Quantum Physics. Fields, Particles, Algebras. 2nd., rev. and enlarged ed. Texts and Monographs in Physics. Springer, Berlin-Heidelberg-New York. (1996). 49

  31. [31]

    Halvorson and M

    H. Halvorson and M. Müger. Algebraic Quantum Field Theory.https: // arxiv. org/ abs/ math-ph/ 0602036(2006). 49, 50, 51

  32. [32]

    Hamhalter.Quantum Measure Theory

    J. Hamhalter.Quantum Measure Theory. Fundamental Theories of Physics, Vol. 134. Kluwer Academic Publishers, Dordrecht (2003) 40, 43, 45, 49

  33. [33]

    Heil.A Basis Theory Primer: Expanded Edition

    C. Heil.A Basis Theory Primer: Expanded Edition. Springer, New York (2011). 10, 17

  34. [34]

    Hollands and A

    S. Hollands and A. Ranallo. Channel Divergences and Complexity in Algebraic QFT. Commun. Math. Phys. 404, 927-962(2023). 50

  35. [35]

    Jarchow.Locally convex spaces

    H. Jarchow.Locally convex spaces. Mathematische Leitfäden. Stuttgart: B. G. Teubner (1981). 2, 17, 19, 22, 24, 34, 36, 37, 40

  36. [36]

    Jarchow and R

    H. Jarchow and R. Ott. On trace ideals.Math. Nachr. 108, 23-37(1982). 34

  37. [37]

    R. V. Kadison and J. R. Ringrose.Fundamentals of the theory of operator algebras. Vol. 1: Elementary theory. Pure and Applied Mathematics, 100. New York-London etc.: Academic Press. XV (1983). 8, 14, 21, 28, 43

  38. [38]

    R. V. Kadison and J. R. Ringrose.Fundamentals of the theory of operator algebras. Vol. 2: Advanced theory. Pure and Applied Mathematics, 100. New York-London etc.: Academic Press. XV (1986). 3, 51, 53

  39. [39]

    N. J. Kalton. An elementary example of a Banach space not isomorphic to its complex conjugate.Can. Math. Bull. 38, No.2, 218-222(1995). 8, 12

  40. [40]

    Laurie, E

    C. Laurie, E. Nordgren, H. Radjavi, and P. Rosenthal. On triangularization of algebras of operators.J. Reine Angew. Math. 327, 143-155(1981). 40

  41. [41]

    Sascha Lill.Time Dynamics in Quantum Field Theory Systems. Ph.D. thesis, Mathematisch-Naturwissenschaftliche Fakultät der Eberhard-Karls-Universität Tübin- gen (2022). 49

  42. [42]

    Lindenstrauss and A

    J. Lindenstrauss and A. Pełczyński. Absolutely summing operators inLp-spaces and their applications.Stud. Math. 29, 275-326(1968). 36 58

  43. [43]

    Meise and D

    R. Meise and D. Vogt.Introduction to Functional Analysis. Transl. from the German by M. S. Ramanujan. Oxford Graduate Texts in Mathematics. Clarendon Press. Oxford (1997). 18, 37

  44. [44]

    G. J. Murphy.C∗-algebras and operator theory. Academic Press, Inc., Boston, MA etc. (1990) 12, 20, 31, 32, 35, 37, 40, 43, 50

  45. [45]

    M. A. Nielsen and I. L. Chuang.Quantum computation and quantum information - 10th Anniversary Edition. Cambridge University Press, Cambridge (2010). 28, 30

  46. [46]

    F. Oertel. Local properties of accessible injective operator ideals.Czech. Math. J. 48, No.1, 119-133(1998). 48

  47. [47]

    F. Oertel. On normed products of operator ideals which containL2 as a factor.Arch. Math. 80, 61-70(2003). 33

  48. [48]

    F. Oertel. On random measures, unordered sums and discontinuities of the first kind. https: // arxiv. org/ abs/ math/ 0609395(2006). 10

  49. [49]

    Oertel and M

    F. Oertel and M. P. Owen. Geometry of polar wedges in Riesz spaces and super- replication prices in incomplete financial markets.Positivity 13, No.1, 201-224(2009). 53

  50. [50]

    Oertel.Upper bounds for Grothendieck constants, quantum correlation matrices and CCP functions

    F. Oertel.Upper bounds for Grothendieck constants, quantum correlation matrices and CCP functions. Lecture Notes in Mathematics 2349. Springer, Cham (2024). 7, 25, 26, 28, 30, 53

  51. [51]

    Oertel.Local structures in quasi-normed operator ideals and trace duality: a unifying framework

    F. Oertel.Local structures in quasi-normed operator ideals and trace duality: a unifying framework. Work in Progress. 15, 39, 47, 48

  52. [52]

    Pankov.Wigner-type theorems for Hilbert Grassmannians

    M. Pankov.Wigner-type theorems for Hilbert Grassmannians. London Mathematical Society Lecture Note Series 460. Cambridge University Press, Cambridge (2020). 7

  53. [53]

    P. Pajot. La revanche d’un théorème oublié (in French).https: // www. larecherche. fr/ la-revanche-dun-théorème-oublié(2015). 36

  54. [54]

    G. K. Pedersen.Analysis now. Graduate Texts in Mathematics 118. Springer, New York (1989). 31, 42, 51

  55. [55]

    G. K. Pedersen.C ∗-Algebras and Their Automorphism Groups. Edited by S. Eilers and D. Olesen. 2nd edition. Pure and Applied Mathematics. Elsevier/Academic Press, Amsterdam (2018). 31, 51

  56. [56]

    Pietsch.Operator ideals

    A. Pietsch.Operator ideals. North-Holland Mathematical Library 20. North-Holland, Amsterdam (1980). 2, 6, 33, 36, 37, 47

  57. [57]

    A. Pietsch. Operator Ideals with a Trace.Math. Nachr. 100, 61-91(1981). 34

  58. [58]

    Pietsch.Eigenvalues and s-numbers

    A. Pietsch.Eigenvalues and s-numbers. Cambridge Studies in Advanced mathematics,

  59. [59]

    34, 46, 47, 48 59

    Cambridge University Press, Cambridge (1987). 34, 46, 47, 48 59

  60. [60]

    A. Pietsch. Traces of operators and their history.Acta Comment. Univ. Tartu. Math. 18, No. 1, 51-64(2014). 17, 18, 34, 46

  61. [61]

    Rédei and S

    M. Rédei and S. J. Summers. When Are Quantum Systems Operationally Independent? Int. J. Theor. Phys. 49, 3250-3261(2010). 36, 50

  62. [62]

    M. A. Rieffel and A. van Daele. A bounded operator approach to Tomita-Takesaki theory.Pacific J. Math. 69, 187-221(1977). 51

  63. [63]

    B. W. Roberts.Reversing the arrow of time. Cambridge University Press, Cambridge - open access (2022). 7

  64. [64]

    Rüßmann.Tensor Product of Hilbert Spaces

    R. Rüßmann.Tensor Product of Hilbert Spaces. M.Sc. thesis, Faculty of Mathematics, TU Kaiserslautern, Germany (2020). 3

  65. [65]

    R. A. Ryan.Introduction to tensor products of Banach spaces. Springer Monographs in Mathematics. Springer, London (2002). 36

  66. [66]

    Schumann

    R. Schumann. Operatorenideale und die statistische Unabhängigkeit in der Quanten- feldtheorie (in German). Dissertation, Georg-August-Universität zu Göttingen (1994). 4, 36, 50, 56

  67. [67]

    Schumann

    R. Schumann. Operator ideals and the statistical independence in quantum field theory. Lett. Math. Phys. 37, No.3, 249-271(1996). 4, 36, 50, 52

  68. [68]

    L. K. Singh and A. Peperko. Sherman-Takeda type theorems for locally C∗-algebras. https: // arxiv. org/ abs/ 2601. 00717(2026). 31

  69. [69]

    S. J. Summers. Tomita-Takesaki Modular Theory.https: // arxiv. org/ abs/ math-ph/ 0511034(2005). 51

  70. [70]

    V. S. Sunder.Operators on Hilbert space. Texts and Readings in Mathematics 71. Springer Science+Business Media Singapore 2016 and Hindustan Book Agency (2016). 34, 35

  71. [71]

    M. Thill. Introduction to Normed∗-Algebras and their Representations, 7th ed.https: // arxiv. org/ abs/ 0807. 4242(2025) 35

  72. [72]

    Trèves.Topological vector spaces, distributions and kernels

    F. Trèves.Topological vector spaces, distributions and kernels. Pure and Applied Math- ematics (Academic Press) 25. New York-London: Academic Press (1967). 9, 12

  73. [73]

    Symmetries and Measurement in Quantum Field Theory - April 7-11, 2025

    R. Verch. Lecture Notes on Operator Algebras and Quantum Field Theory. EMS-IAMP Spring School “Symmetries and Measurement in Quantum Field Theory - April 7-11, 2025”.https: // arxiv. org/ abs/ 2507. 00900(2025). 49, 51

  74. [74]

    G. Warner. Positivity.http://www.math.washington.edu/~warner/Positivity_ Warner.pdf.Unpublished(2008). 31

  75. [75]

    G. Warner. C∗-algebras.http://www.math.washington.edu/~warner/C-star.pdf. Unpublished(2010). 31 60

  76. [76]

    Weidmann.Linear operators in Hilbert spaces

    J. Weidmann.Linear operators in Hilbert spaces. Transl. by Joseph Szücs. Graduate Texts in Mathematics, Vol. 68. Springer, New York (1980). 51

  77. [77]

    Werner.Functional analysis

    D. Werner.Functional analysis. 7th revised edition(in German). Springer, Berlin (2011). 6, 11, 12, 17, 18, 20, 22, 31, 39, 41, 45, 49

  78. [78]

    R. Werner. Local preparability of states and the split property in quantum field theory. Lett Math Phys 13, 325-329(1987). 36

  79. [79]

    Zwarich.Von Neumann Algebras for Abstract Harmonic Analysis

    C. Zwarich.Von Neumann Algebras for Abstract Harmonic Analysis. M.Sc. thesis, University of Waterloo, Canada (2008). Available viahttps://uwspace.uwaterloo. ca/bitstreams/4b497e8c-779f-4c75-b6cf-b397c5f5c315/download. 31 61