551 research outputs found
Changing shapes: adiabatic dynamics of composite solitary waves
We discuss the solitary wave solutions of a particular two-component scalar
field model in two-dimensional Minkowski space. These solitary waves involve
one, two or four lumps of energy. The adiabatic motion of these composite
non-linear non-dispersive waves points to variations in shape.Comment: 21 pages, 15 figures. To appear in Physica D: Nonlinear Phenomen
Kink fluctuation asymptotics and zero modes
In this paper we propose a refinement of the heat kernel/zeta function
treatment of kink quantum fluctuations in scalar field theory, further
analyzing the existence and implications of a zero energy fluctuation mode.
Improved understanding of the interplay between zero modes and the kink heat
kernel expansion delivers asymptotic estimations of one-loop kink mass shifts
with remarkably higher precision than previously obtained by means of the
standard Gilkey-DeWitt heat kernel expansion.Comment: 21 pages, 8 figures, to be published in The European Physical Journal
On the semiclassical mass of -kinks
One-loop mass shifts to the classical masses of stable kinks arising in a
massive non-linear -sigma model are computed. Ultraviolet
divergences are controlled using the heat kernel/zeta function regularization
method. A comparison between the results achieved from exact and
high-temperature asymptotic heat traces is analyzed in depth.Comment: RevTex file, 15 pages, 2 figures. Version to appear in Journal of
Physics
On domain walls in a Ginzburg-Landau non-linear S^2-sigma model
The domain wall solutions of a Ginzburg-Landau non-linear -sigma hybrid
model are unveiled. There are three types of basic topological walls and two
types of degenerate families of composite - one topological, the other
non-topological- walls. The domain wall solutions are identified as the finite
action trajectories (in infinite time) of a related mechanical system that is
Hamilton-Jacobi separable in sphero-conical coordinates. The physical and
mathematical features of these domain walls are thoroughly discussed.Comment: 26 pages, 18 figure
The Kink variety in systems of two coupled scalar fields in two space-time dimensions
In this paper we describe the moduli space of kinks in a class of systems of
two coupled real scalar fields in (1+1) Minkowskian space-time. The main
feature of the class is the spontaneous breaking of a discrete symmetry of
(real) Ginzburg-Landau type that guarantees the existence of kink topological
defects.Comment: 12 pages, 5 figures. To appear in Phys. Rev.
Solitary Waves in Massive Nonlinear S^N-Sigma Models
The solitary waves of massive (1+1)-dimensional nonlinear S^N-sigma models
are unveiled. It is shown that the solitary waves in these systems are in
one-to-one correspondence with the separatrix trajectories in the repulsive
N-dimensional Neumann mechanical problem. There are topological (heteroclinic
trajectories) and non-topological (homoclinic trajectories) kinks. The
stability of some embedded sine-Gordon kinks is discussed by means of the
direct estimation of the spectra of the second-order fluctuation operators
around them, whereas the instability of other topological and non-topological
kinks is established applying the Morse index theorem
Supersymmetry versus Integrability in two-dimensional Classical Mechanics
Supersymmetric extensions of Hamilton-Jacobi separable Liouville mechanical
systems with two degrees of freedom are defined. It is shown that supersymmetry
can be implemented in this type of systems in two independent ways. The
structure of the constants of motion is unveiled and the entanglement between
integrability and supersymmetry is explored.Comment: 28 pages, Added reference
Quantum magnetic flux lines, BPS vortex zero modes, and one-loop string tension shifts
Spectral heat kernel/zeta function regularization procedures are employed in
this paper to control the divergences arising from vacuum fluctuations of
Bogomolnyi-Prasad-Sommerfield vortices in the Abelian Higgs model. Zero modes
of vortex fluctuations are the source of difficulties appearing when the
standard Gilkey-de Witt expansion is performed. A modified GdW expansion is
developed to diminish the impact of the infrared divergences due to the vortex
zero modes. With this new technique at our disposal we compute the one-loop
vortex mass shift in the planar AHM and the quantum corrections to the string
tension of the magnetic flux tubes living in three dimensions. In both cases it
is observed that weak repulsive forces surge between these classically non
interacting topological defects caused by vacuum quantum fluctuations.Comment: 25 pages, 2 figure
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