6 citations · 23 across the 22 of their papers we have counts for
16 papers · 1 filter
On a recent calculation of the mass spectra of quarkonia using the Cornell potential with spin-spin interactions
Francisco M. Fernández
We analyse a recent application of the Cornell potential with spin-spin interaction to the mass spectra of quarkonia and show that the authors have in fact used the Kratzer-Fues po…
On some one-dimensional quantum-mechanical models with a delta-potential interaction
Francisco M. Fernández
We discuss a systematic construction of dimensionless quantum-mechanical equations. The process reduces the number of independent model parameters to a minimum and, at the same tim…
On the effective secular equation
Francisco M. Fernández
We show that the effective secular equation proposed several years ago is suitable for estimating the location of the exceptional points of eigenvalue equations. As an illustrative…
Algebraic analysis of non-Hermitian quadratic Hamiltonians
Francisco M. Fernández
We study a general one-mode non-Hermitian quadratic Hamiltonian that does not exhibit -symmetry. By means of an algebraic method we determine the conditions for the e…
On the interaction of a magnetic quadrupole moment with an electric field in a rotating frame
Francisco M. Fernández
We discuss results obtained recently for a quantum-mechanical model given by a neutral particle with a magnetic quadrupole moment in a radial electric field and a scalar potential…
On the problem of the vanishing discriminant
Francisco M. Fernández
We show that the straightforward application of the discriminant to some physical problems may yield a trivial useless result. If the symmetry of the model matrix does not change w…
On the application of the Adomian-based methods
Francisco M. Fernández
We analyze a recent application of two Adomian-based approximate methods to the Chen-Lee-Liu equation. We prove that the outcome of these approaches is merely the Taylor expansion…
Quantum particles in a suddenly accelerating potential
Paolo Amore, Francisco M. Fernández, Jose Luis Valdez
We study the behavior of a quantum particle trapped in a confining potential in one dimension under multiple sudden changes of velocity and/or acceleration. We develop the appropri…
Extremely broken generalized symmetry
Francisco M. Fernández
We discuss some simple Hückel-like matrix representations of non-Hermitian operators with antiunitary symmetries that include generalized (parity transformation foll…
On the Rayleigh-Ritz variational method
Francisco M. Fernández
We give a simple proof of the well known fact that the approximate eigenvalues provided by the Rayleigh-Ritz variational method are increasingly accurate upper bounds to the exact…
On the misinterpretation of conditionally-solvable quantum-mechanical problems
Francisco M. Fernández
We apply the Frobenius (power-series) method to some simple exactly-solvable and conditionally-solvable quantum-mechanical models with supposed physical interest. We show that the…
On the Q-BOR-FDTD method
Francisco M. Fernández
We discuss a recently proposed approach termed Q-BOR-FDTD method and develop its main equations in a clearer and more rigorous way. We show that it is unsuitable for the calculatio…
Alternative solution to a quantum-mechanical four-particle system in one dimension
Francisco M. Fernández
We propose an alternative solution to a quantum-mechanical four-particle system in one dimension with two- and three-particle interactions. The solution of the eigenvalue equation…
On the quantum-mechanical singular harmonic oscillator
Francisco M. Fernández
We obtain the eigenvalues and eigenfunctions of the singular harmonic oscillator by means of the simple and straightforward Frobenius (power-series) method. F…
A most misunderstood conditionally-solvable quantum-mechanical model
Francisco M. Fernández
In this paper we show that several authors have derived wrong physical conclusions from a gross misunderstanding of the exact eigenvalues and eigenfunctions of a conditionally-solv…
On a class of non-Hermitian Hamiltonians with tridiagonal matrix representation
Francisco M. Fernández
We show that some non-Hermitian Hamiltonian operators with tridiagonal matrix representation may be quasi Hermitian or similar to Hermitian operators. In the class of Hamiltonian o…