29 citations · 65 across the 20 of their papers we have counts for
21 papers
Complex oscillations of non-definite Sturm-Liouville problems, II
Angelo B. Mingarelli
We correct and update a result of R.G.D. Richardson [13] dealing with the separation of zeros of the real and imaginary parts of non-real eigenfunctions of non-definite Sturm-Liouv…
On the non-existence of oscillation numbers in Sturm-Liouville theory
Angelo B. Mingarelli
We prove an old conjecture that relates the existence of non-real eigenvalues of Sturm-Liouville Dirichlet problems on a finite interval to the non-existence of oscillation numbers…
On a converse of Sturm's comparison theorem
Angelo B. Mingarelli
We show that Sturm's classical comparison theorem (SCT) on the interlacing of zeros of solutions of pairs of real second order two-term ordinary differential equations necessarily…
On the basic theory of some generalized and fractional derivatives
Leila Gholizadeh Zivlaei, Angelo B. Mingarelli
We continue the development of the basic theory of generalized derivatives as introduced in \cite{JPA} and give some of their applications. In particular, we formulate versions of…
The converse of Sturm's Separation Theorem
L. Gholizadeh, A. B. Mingarelli
We show that Sturm's classical separation theorem on the interlacing of the zeros of linearly independent solutions of real second order two-term ordinary differential equations ne…
Uncertainty Principles in Krein Space
Sirous Homayouni, Angelo B. Mingarelli
Uncertainty relations between two general non-commuting self-adjoint operators are derived in a Krein space. All of these relations involve a Krein space induced fundamental symmet…