6,407 research outputs found
Generalized scalar field models with the same energy density and linear stability
We study how the properties of a Lagrangian density for a single real scalar
field in flat spacetime change with inclusion of an overall factor depending
only on the field. The focus of the paper is to obtain analytical results. So,
we show that even though it is possible to perform a field redefinition to get
an equivalent canonical model, it is not always feasible to write the canonical
model in terms of elementary functions. Also, we investigate the behavior of
the energy density and the linear stability of the solutions. Finally, we show
that one can find a class of models that present the same energy density and
the same stability potential.Comment: 6 pages, 4 figure
From Kinks to Compactons
This work deals with the presence of localized structures in relativistic
systems described by a single real scalar field in two-dimensional spacetime.
We concentrate on kinks and compactons in models with standard kinematics, and
we develop a procedure that help us to smoothly go from kinks to compactons in
the suggested scenario. We also show how the procedure works in the braneworld
scenario, for flat brane in the five-dimensional spacetime with a single extra
dimension of infinite extent. The brane unveils a hybrid profile when the kink
becomes a compacton, behaving as a thick or thin brane, depending on the extra
dimension being inside or outside a compact space.Comment: 7 pages, 7 figures; new version, to appear in PL
Study of models of the sine-Gordon type in flat and curved spacetime
We study a new family of models of the sine-Gordon type, starting from the
sine-Gordon model, including the double sine-Gordon, the triple one, and so on.
The models appears as deformations of the starting model, with the deformation
controlled by two parameters, one very small, used to control a linear
expansion on it, and the other, which specifies the particular model in the
family of models. We investigate the presence of topological defects, showing
how the solutions can be constructed explicitly from the topological defects of
the sine-Gordon model itself. In particular, we delve into the double
sine-Gordon model in a braneworld scenario with a single extra dimension of
infinite extent, showing that a stable gravity scenario is admissible. Also, we
briefly show that the deformation procedure can be used iteratively, leading to
a diversity of possibilities to construct families of models of the sine-Gordon
type.Comment: 8 pages, 7 figures; Title changed, author and new results included;
version to appear in EPJ
Analytic vortex solutions in generalized models of the Maxwell-Higgs type
This work deals with the presence of analytical vortex configurations in
generalized models of the Maxwell-Higgs type in the three-dimensional
spacetime. We implement a procedure that allows to decouple the first order
equations, which we use to solve the model analytically. The approach is
exemplified with three distinct models that show the robustness of the
construction. In the third model, one finds analytical solutions that exhibit
interesting compact vortex behavior.Comment: 9 pages, 10 figures. To appear in PL
Compact Structures in Standard Field Theory
We investigate the presence of static solutions in models described by real
scalar field in two-dimensional spacetime. After taking advantage of a
procedure introduced sometime ago, we solve intricate nonlinear ordinary
differential equations and illustrate how to find compact structures in models
engendering standard kinematics. In particular, we study linear stability and
show that all the static solutions we have found are linearly stable.Comment: 6 pages, 11 figures; version published in EP
Vortices in a generalized Maxwell-Higgs model with visible and hidden sectors
We investigate the presence of vortices in generalized Maxwell-Higgs models
with a hidden sector. The model engenders symmetry, in a
manner that the sectors are coupled via the visible magnetic permeability
depending only on the hidden scalar field. We develop a first order framework
in which the hidden sector decouples from the visible one. We illustrate the
results with two specific examples, that give rise to the presence of vortices
with internal structure.Comment: 9 two-column pages, 4 figures; version to appear in AHE
First-order formalism for twinlike models with several real scalar fields
We investigate the presence of twinlike models in theories described by
several real scalar fields. We focus on the first-order formalism, and we show
how to build distinct scalar field theories that support the same extended
solution, with the same energy density and the very same linear stability. The
results are valid for two distinct classes of generalized models, that include
the standard model and cover a diversity of generalized models of current
interest in high energy physics.Comment: 9 pages; Version to appear in EPJ
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