3,143 research outputs found
Qualitative properties and existence of sign changing solutions with compact support for an equation with a p-Laplace operator
We consider radial solutions of an elliptic equation involving the p-Laplace
operator and prove by a shooting method the existence of compactly supported
solutions with any prescribed number of nodes. The method is based on a change
of variables in the phase plane corresponding to an asymptotic Hamiltonian
system and provides qualitative properties of the solutions
BPS Skyrme neutron stars in generalized gravity
We study the coupling of nuclear matter described by the BPS Skyrme model to
generalized gravity. Concretely, we consider the Starobinsky model which
provides the leading-order correction to the Einstein-Hilbert action. Static
solutions describing neutron stars are found both for the full field theory and
for the mean-field approximation. We always consider the full Starobinsky model
in the nonperturbative approach, using appropriately generalized shooting
methods for the numerical neutron star calculations. Many of our results are
similar to previous investigations of neutron stars for the Starobinsky model
using other models of nuclear matter, but there are some surprizing
discrepancies. The "Newtonian mass" relevant for the surface redshift, e.g.,
results larger than the ADM mass in our model, in contrast to other
investigations. This difference is related to the particularly high stiffness
of nuclear matter described by the BPS Skyrme model and offers an interesting
possibility to distinguish different models of nuclear matter within
generalized gravity.Comment: LaTex, 28 pages, 13 figures; v2: minor change
The effects of retardation on the topological plasmonic chain: plasmonic edge states beyond the quasistatic limit
We study a one-dimensional plasmonic system with non-trivial topology: a
chain of metallic nanoparticles with alternating spacing, which is the
plasmonic analogue to the Su-Schreiffer-Heeger model. We extend previous
efforts by including long range hopping with retardation and radiative damping,
which leads to a non-Hermitian Hamiltonian with frequency dependence. We
calculate band structures numerically and show that topological features such
as quantised Zak phase persist due to chiral symmetry. This predicts parameters
leading to topologically protected edge modes, which allows for positioning of
disorder-robust hotspots at topological interfaces, opening up novel
nanophotonics applications
On Regions of Existence and Nonexistence of solutions for a System of --Laplacians
We give a new region of existence of solutions to the superhomogeneous
Dirichlet problem \quad \begin{array}{l} -\Delta_{p} u= v^\delta\quad
v>0\quad {in}\quad B,\cr -\Delta_{q} v = u^{\mu}\quad u>0\quad {in}\quad B, \cr
u=v=0 \quad {on}\quad \partial B, \end{array}\leqno{(S_R)} where is the
ball of radius centered at the origin in \RR^N. Here
and is the Laplacian
operator for .Comment: 17 pages, accepted in Asymptotic Analysi
- …