80 citations · 111 across the 6 of their papers we have counts for
6 papers
The Coupled Cluster Method and Entanglement
Péter Lévay, Szilvia Nagy, János Pipek +1
The Coupled Cluster (CC) and full CI expansions are studied for three fermions with six and seven modes. Surprisingly the CC expansion is tailor made to characterize the usual SLOC…
On an economic prediction of the finer resolution level wavelet coefficients in electron structure calculations
Szilvia Nagy, János Pipek
In wavelet based electron structure calculations introducing a new, finer resolution level is usually an expensive task, this is why often a two-level approximation is used with ve…
A study of two-qubit density matrices with fermionic purifications
Szilárd Szalay, Péter Lévay, Szilvia Nagy +1
We study 12 parameter families of two qubit density matrices, arising from a special class of two-fermion systems with four single particle states or alternatively from a four-qubi…
The kinetic energy operator in the subspaces of wavelet analysis
J. Pipek, Sz. Nagy
At any resolution level of wavelet expansions the physical observable of the kinetic energy is represented by an infinite matrix which is ``canonically'' chosen as the projection o…
Refinement trajectory and determination of eigenstates by a wavelet based adaptive method
J. Pipek, Sz. Nagy
The detail structure of the wave function is analyzed at various refinement levels using the methods of wavelet analysis. The eigenvalue problem of a model system is solved in gran…
An elementary formula for entanglement entropies of fermionic systems
Péter Lévay, Szilvia Nagy, János Pipek
An elementary formula for the von Neumann and Renyi entropies describing quantum correlations in two-fermionic systems having four single particle states is presented. An interesti…