10 citations · 34 across the 21 of their papers we have counts for
22 papers
Algebro-geometric approach to a fermion self-consistent field theory on coset space SU(m+n)/S(U(m) x U(n))
Seiya Nishiyama, Joao da Providencia
The integrability-condition method is regarded as a mathematical tool to describe the symmetry of collective sub-manifold. We here adopt the particle-hole representation. In the co…
A quantum system with a non-Hermitian Hamiltonian
Natália Bebiano, João da Providência, S. Nishiyama +1
The relevance in Physics of non-Hermitian operators with real eigenvalues is being widely recognized not only in quantum mechanics but also in other areas, such as quantum optics,…
Fermionic model with a non-Hermitian Hamiltonian
Natália Bebiano, João da Providência, Seiya Nishiyama +1
This paper deals with the mathematical spectral analysis and physical interpretation of a fermionic system described by a non-Hermitian Hamiltonian possessing real eigenvalues. A s…
Remarks on the Mean-Field Theory Based on the SO(2N+1) Lie Algebra of the Fermion Operators
Seiya Nishiyama, Joao Da Providencia
Toward a unified algebraic theory for mean-field Hamiltonian (MFH) describing paired- and unpaired-mode effects, in this paper, we propose a generalized HB (GHB) MFH in terms of th…
Mean-field theory based on the \mathfrak{Jacobi~hsp} := semi-direct sum \mathfrak{h}_N \rtimes \mathfrak{sp}(2N,\mathbb{R})_\mathbb{C} algebra of boson operators
Seiya Nishiyama, Joao Da Providencia
In this paper, we give an expression for canonical transformation group with Grassmann variables, basing on the \mathfrak{Jacobi~hsp} \!:= semi-direct sum \mathfrak{h}_{N} \rtimes…
Velocity operator approach to a Fermion system
Seiya Nishiyama, Joao da Providencia
In this paper, we formulate a velocity operator approach to a three-dimensional (3D) Fermion system. Following Sunakawa, introducing density and velocity operators, we treat 3D qua…