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arXiv · math-ph/9910031

The quantum information manifold for epsilon-bounded forms

M. R. Grasselli·R. F. Streater
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Abstract

Let H be a self-adjoint operator bounded below by 1, and let V be a small form perturbation such that RVS has finite norm, where R is the resolvent at zero to the power 1/2 +epsilon, and S is the resolvent to the power 1/2-epsilon. Here, epsilon lies between 0 and 1/2. If the Gibbs state defined by H is sufficiently regular, we show that the free energy is an analytic function of V in the sense of Frechet, and that the family of density operators defined in this way is an analytic manifold modelled on a Banach space.

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M. R. Grasselli, R. F. Streater. 1999-10-19. The quantum information manifold for epsilon-bounded forms. https://doi.org/10.1016/s0034-4877(00)90003-x

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