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Problems with the definition of renormalized Hamiltonians for momentum-space renormalization transformations

79   0   0.0 ( 0 )
 Publication date 1998
  fields Physics
and research's language is English




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For classical lattice systems with finite (Ising) spins, we show that the implementation of momentum-space renormalization at the level of Hamiltonians runs into the same type of difficulties as found for real-space transformations: Renormalized Hamiltonians are ill-defined in certain regions of the phase diagram.



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