3,604 research outputs found
Anharmonic Oscillators with Infinitely Many Real Eigenvalues and PT-Symmetry
We study the eigenvalue problem in the complex plane
with the boundary condition that decays to zero as tends to infinity
along the two rays , where
for complex-valued polynomials of degree at most
. We provide an asymptotic formula for eigenvalues and a necessary
and sufficient condition for the anharmonic oscillator to have infinitely many
real eigenvalues
Trace Formulas for Non-Self-Adjoint Periodic Schr\"odinger Operators and some Applications
Recently, a trace formula for non-self-adjoint periodic Schr\"odinger
operators in associated with Dirichlet eigenvalues was proved
in [9]. Here we prove a corresponding trace formula associated with Neumann
eigenvalues.
In addition we investigate Dirichlet and Neumann eigenvalues of such
operators. In particular, using the Dirichlet and Neumann trace formulas we
provide detailed information on location of the Dirichlet and Neumann
eigenvalues for the model operator with the potential , where
.Comment: 26 pages, no figure
The potential (iz)^m generates real eigenvalues only, under symmetric rapid decay conditions
We consider the eigenvalue problems -u"(z) +/- (iz)^m u(z) = lambda u(z), m
>= 3, under every rapid decay boundary condition that is symmetric with respect
to the imaginary axis in the complex z-plane. We prove that the eigenvalues
lambda are all positive real.Comment: 23 pages and 1 figur
Neutrino Flavor Ratio on Earth and at Astrophysical Sources
We present the reconstruction of neutrino flavor ratios at astrophysical
sources. For distinguishing the pion source and the muon-damped source to the
3 level, the neutrino flux ratios,
and
, need to be measured in accuracies better
than 10%.Comment: 3 pages, 8 figures. Talk presented by T.C. Liu in ERICE 2009, Sicily
- …