Abstract
Let ℳ be a von Neumann algebra with a cyclic and separating vector Ω. Let δ=i[H, ·] be the spatial derivation implemented by a selfadjoint operatorH, such thatHΩ=0. Let Δ be the modular operator associated with the pair (ℳ, Ω). We prove the equivalence of the following three conditions:
1)H is essential selfadjoint onD(δ)Ω, andH commutes strongly with Δ.
2) The restriction ofH toD(δ)Ω is essential selfadjoint onD(Δ1/2) equipped with the inner product
(ξ|η)#=(ξ|η)+(Δ1/2ξ|Δ1/2η), ξ, η ∈D(Δ1/2).
3) exp (itH) ℳ exp (−itH)=ℳ for anyt∈ℝ.
We show by an example, that the first part of 1),H is essential selfadjoint onD(δ)Ω, does not imply 3). This disproves a conjecture due to Bratteli and Robinson [3].
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References
Arveson, W.: On groups of automorphisms of operator algebras. J. Funct. Anal.15, 217–243 (1974)
Bogolubov, N. N., Lagunov, A. A., Todorov, I. T.: Introduction to axiomatic quantum field theory. Reading, Mass.: Benjamin 1975
Bratteli, O., Robinson, D. W.: Unbounded derivations of von Neumann algebras. Ann. Inst. Henri Poincaré A25, 139–164 (1976)
Bratteli, O., Robinson, D. W.: Unbounded derivations and invariant trace states. Commun. math. Phys.46, 31–35 (1976)
Bratteli, O., Robinson, D. W.: Greens functions, Hamiltonians, and modular automorphisms. Commun. math. Phys.50, 135–156 (1976)
Bratteli, O., Herman, R. H., Robinson, D. W.: Quasianalytic vectors and derivations of operator algebras. Math. Scand.39, 371–381 (1976)
Bratteli, O.: Unbounded derivations and invariant states. ZIF Preprint, unpublished (1976)
Connes, A.: Une classification de facteurs de type III. Ann. Sci. Ecole Norm. Sup.6, 133–252 (1973)
Digernes, T.: Duality for weights on covariant systems and its application. U.C.L.A. Thesis (1975)
Gallavotti, G., Pulvirenti, M.: Classical KMS condition and Tomita-Takesaki theory. Commun. math. Phys.46, 1–9 (1976)
Greenleaf, F. P.: Invariant means on topological groups. New York: van Nostrand 1969
Haag, R., Kastler, D.: An algebraic approach to quantum field theory. J. Math. Phys.5, 848–861 (1964)
Haagerup, U.: On the dual weights for von Neumann algebras. I. Preprint, Odense (1975)
Herman, R. H.: Implementation and the core problem. ZIF Preprint (1975)
Kato, T.: Perturbation theory for linear operators. Berlin-Heidelberg-New York: Springer 1966
Leeuw, K. de: On the adjoint semigroup and some problems in the theory of approximation. Math. Z.73, 219–239 (1960)
Nelson, E.: Notes on non-commutative integration. J. Funct. Anal.15, 103–116 (1974)
Nelson, E.: Analytic vectors. Ann. Math.70, 572–615 (1959)
Pedersen, G. K., Takesaki, M.: The Radon-Nikodym theorem for von Neumann algebras. Acta Math.130, 53–87 (1973)
Pulvirenti, M., Tirozzi, B.: Time evolution of a quantum lattice system. Commun. math. Phys.30, 83–98 (1973)
Robinson, D. W.: Statistical mechanics for quantum spin systems. Commun. math. Phys.7, 337–348 (1968)
Robinson, D. W.: Dynamics in quantum statistical mechanics. Proceedings of the ZIF Conference, Bielefeld 1976 (to appear)
Segal, I.: A non-commutative extention of abstract integration. Ann. Math.58, 595–596 (1953)
Streater, R.: On certain non-relativistic quantized fields. Commun. math. Phys.7, 93–98 (1968)
Takesaki, M.: Tomitas theory of modular Hilbert algebras and its applications. Lecture notes in mathematics, Vol. 128. Berlin-Heidelberg-New York: Springer 1970
Takesaki, M.: The structure of a von Neumann algebra with a homogenuous periodic state. Acta Math.131, 79–121 (1973)
Takesaki, M.: Duality for crossed products and the structure of von Neumann algebras of type III. Acta Math.131, 249–310 (1973)
Winnink, M.: In: Statistical mechanics and field theory (eds. R. Sen, C. Weil). Jerusalem: Keter Publishing House 1971
Kadison, R.: Remarks on the type of von Neumann algebras of local observables in quantum field theory. J. Math. Phys.4, 1511–1516 (1963)
Dixmier, J., Marechal, O.: Vecteurs totalisateurs d'une algèbre de von Neumann. Commun. math. Phys.22, 44–50 (1970)
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Communicated by H. Araki
Part of this work was done while O.B. was a member of Zentrum für interdisziplinäre Forschung der Universität Bielefeld
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Bratteli, O., Haagerup, U. Unbounded derivations and invariant states. Commun.Math. Phys. 59, 79–95 (1978). https://doi.org/10.1007/BF01614156
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DOI: https://doi.org/10.1007/BF01614156