Comment on 'Quantum Backreaction on "Classical" Variables'

It is argued that the bracket of Anderson's canonical theory should have been antisymmetric otherwise serious controversies arise like violation of both hermiticity and the Leibniz rule of differentiation.Comment: 3 pages, LaTe

Alien Registration- Boucher, Marie A. (Augusta, Kennebec County)

https://digitalmaine.com/alien_docs/18378/thumbnail.jp

Mixed Heisenberg Chains. II. Thermodynamics

We consider thermodynamic properties, e.g. specific heat, magnetic susceptibility, of alternating Heisenberg spin chains. Due to a hidden Ising symmetry these chains can be decomposed into a set of finite chain fragments. The problem of finding the thermodynamic quantities is effectively separated into two parts. First we deal with finite objects, secondly we can incorporate the fragments into a statistical ensemble. As functions of the coupling constants, the models exhibit special features in the thermodynamic quantities, e.g. the specific heat displays double peaks at low enough temperatures. These features stem from first order quantum phase transitions at zero temperature, which have been investigated in the first part of this work.Comment: 12 pages, RevTeX, 12 embedded eps figures, cf. cond-mat/9703206, minor modification

The stiff-man syndrome

In 1956 Moersch and Woltman first recorded a state of 'progressive fluctuating rigidity and spasm', for which they coined the term 'stiff-man syndrome', signifying that the aetiology and pathogenesis of the condition were unknown. At the time of writing only 16 cases have been described. It. is suggested that the case under consideration falls into this syndrome, although there are a number of features at variance with the published cases

Alien Registration- Boucher, Anna Marea A. (Lewiston, Androscoggin County)

https://digitalmaine.com/alien_docs/30589/thumbnail.jp

Absence of classical and quantum mixing

It is shown, under mild assumptions, that classical degrees of freedom dynamically coupled to quantum ones do not inherit their quantum fluctuations. It is further shown that, if the assumptions are strengthen by imposing the existence of a canonical structure, only purely classical or purely quantum dynamics are allowed.Comment: REVTeX, 4 page