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1.
The O(3) sigma model and abelian Higgs model in two space dimensions admit topological (Bogomol'nyi) lower bounds on their
energy. This paper proposes lattice versions of these systems which maintain the Bogomol'nyi bounds. One consequence is that
instantons/solitons/vortices on the lattice then have a high degree of stability.
Received: 29 February 1996 / Accepted: 5 August 1996 相似文献
2.
REN Ji-Rong XU Dong-Hui ZHANG Xin-Hui DUAN Yi-Shi 《理论物理通讯》2008,49(6):1627-1630
We study the properties of the Ginzburg-Landau model at the dual point for the superconductors. By making use of the U(1) gauge potential decomposition and the φ-mapping theory, we investigate the topological inner structure of the Bogomol'nyi equations and deduce a modified decoupled Bogomol'nyi equation with a nontrivial topological term, which is ignored in conventional model. We find that the nontrivial topological term is closely related to the N-vortex, which arises from the zero points of the complex scalar field, Furthermore, we establish a relationship between Ginzburg Landau free energy and the winding number. 相似文献
3.
Jerome P. Gauntlett Neil D. Lambert Peter C. West 《Communications in Mathematical Physics》1999,202(3):571-592
The fivebrane worldvolume theory in eleven dimensions is known to contain BPS threebrane solitons which can also be interpreted
as a fivebrane whose worldvolume is wrapped around a Riemann surface. By considering configurations of intersecting fivebranes
and hence intersecting threebrane solitons, we determine the Bogomol'nyi equations for more general BPS configurations. We
obtain differential equations, generalising Cauchy–Riemann equations, which imply that the worldvolume of the fivebrane is
wrapped around a calibrated submanifold.
Received: 20 April 1998 / Accepted: 16 November 1998 相似文献
4.
M. Temple-Raston 《International Journal of Theoretical Physics》1997,36(4):871-881
A tensor product generalization ofB ∧F theories is proposed that has a Bogomol'nyi structure. Nonsingular, stable, finite-energy particle-like solutions to the
Bogomol'nyi equations are studied. Unlike Yang-Mills(-Higgs) theory, the Bogomol'nyi structure does not appear as a perfect
square in the Lagrangian. Consequently, the Bogomol'nyi energy can be obtained in more than one way. The added flexibility
permits electric monopole solutions. 相似文献
5.
M. Faber 《Few-Body Systems》2001,30(3):149-186
We introduce a model designed to describe charged particles as stable topological solitons of a field with values on the
internal space S
3. These solitons behave like particles with relativistic properties like Lorentz contraction and velocity dependence of mass.
This mass is defined by the energy of the soliton. In this sense this model is a generalization of the Sine-Gordon model1(We do not chase the aim to give a four-dimensional generalization of Coleman’s isomorphism between the Sine-Gordon model
and the Thirring model which was shown in 2-dimensional space-time) from 1 + 1-dimensions to 3 + 1-dimensions, from S
1 to S
3. For large distances from the centre of solitons this model tends to a dual U(1)-theory with freely propagating electromagnetic waves. Already at the classical level it describes important effects, which
usually have to be explained by quantum field theory, like particle-antiparticle annihilation and the running of the coupling.
Received November 30, 1999; revised June 20, 2000; accepted for publication October 2, 2000 相似文献
6.
M. Temple-Raston 《Letters in Mathematical Physics》1991,23(2):91-97
We examine a class of topological field theories defined by Lagrangians that under certain conditions can be written as the sum of two characteristic numbers or winding numbers. Therefore, the action or the energy is a topological invariant and stable under perturbations. The sufficient conditions required for stability take the form of first-order field equations, analogous to the self-duality and Bogomol'nyi equations in Yang-Mills(-Higgs) theory. Solutions to the first-order equations automatically satisfy the full field equations. We show the existence of nontrivial, nonsingular, minimum energy spherically symmetric dyon solutions and that they are stable. We also discuss evidence for a dual field theory to Yang-Mills-Higgs in topological field theory. The existence of dual field theories and electric monopoles is predicted by Montonen and Olive. 相似文献
7.
Peng-Ming Zhang Xi-Guo Lee Shao-Feng Wu 《International Journal of Theoretical Physics》2007,46(12):3234-3241
We investigate the solitons in the CP
N
model in terms of the decomposition of gauge potential. Based on the φ-mapping topological current theory, the charge and position of solitons is determined by the properties of the typical component.
Furthermore, the motion and the bifurcation of multi-soliton is discussed. And the knotted solitons in high dimension is explored
also. 相似文献
8.
The role that the auxiliary scalar field φ plays in Brans–Dicke cosmology is discussed. If a constant vacuum energy is assumed
to be the origin of dark energy, then the corresponding density parameter would be a quantity varying with φ; and almost all
of the fundamental components of our universe can be unified into the dynamical equation for φ. As a generalization of Brans–Dicke
theory, we propose a new gravity theory with a complex scalar field ϕ which is coupled to the cosmological curvature scalar.
Through such a coupling, the Higgs mechanism is naturally incorporated into the evolution of the universe, and a running density
of the field vacuum energy is obtained which may release the particle standard model from the rigorous cosmological constant
problem in some sense. Our model predicts a running mass scale of the fundamental particles in which the gauge symmetry breaks
spontaneously. The running speed of the mass scale in our case could survive all existing experiments. 相似文献
9.
We consider the axion field and electromagnetic waves with rapid time dependence, coupled to a strong time independent, asymptotically approaching a constant at infinity “mean” magnetic field, which takes into account the back reaction from the axion field and electromagnetic waves with rapid time dependence in a time averaged way. The direction of the self consistent mean field is orthogonal to the common direction of propagation of the axion and electromagnetic waves with rapid time dependence and parallel to the polarization of these electromagnetic waves. Then, there is an effective U(1) symmetry mixing axions and photons. Using the natural complex variables that this U(1) symmetry suggests we find localized planar soliton solutions. These solutions appear to be stable since they produce a different magnetic flux than the state with only a constant magnetic field, which we take as our “ground state”. The solitons also have non-trivial U(1) charge defined before, different from the uncharged vacuum. These solitons represent a new, non-gravitational mechanism, of trapping light. They could also affect the vacuum structure in models of the QCD vacuum that incorporate a magnetic condensate, introducing may be gluon axion solitons. 相似文献
10.
This paper presents experimental evidence that orthogonally crossed dark soliton stripes form quasi-two-dimensional spatial
solitons with a soliton constant equal to that of singly charged optical vortices. Besides the pairs of oppositely charged
optical vortex solitons, the snake instability of the dark formation at moderate saturation is found to lead to generation
of steering mixed edge–screw phase dislocations with zero total topological charges.
Received: 26 October 1998 / Revised version: 19 January 1999 / Published online: 12 May 1999 相似文献
11.
C. Adam J. Sánchez-Guillén A. Wereszczyński 《The European Physical Journal C - Particles and Fields》2006,47(2):513-524
Field theories with a S2-valued unit vector field living on S3×ℝ space-time are investigated. The corresponding eikonal equation, which is known to provide an integrable sector for various
sigma models in different spaces, is solved giving static as well as time-dependent multiply knotted configurations on S3 with arbitrary values of the Hopf index. Using these results, we then find a set of hopfions with topological charge QH=m2, m∈Z, in the integrable subsector of the pure CP1 model. In addition, we show that the CP1 model with a potential term provides time-dependent solitons. In the case of the so-called “new baby Skyrme” potential we
find, e.g., exact stationary hopfions, i.e., topological Q-balls. Our results further enable us to construct exact static
and stationary Hopf solitons in the Faddeev–Niemi model with or without the new baby Skyrme potential. Generalizations for
a large class of models are also discussed. 相似文献
12.
We present a summary of the topological and non-topological solitons of a two component field in 1+1 dimensions with application in field theory and in condensed matter physics. We note several intriguing analytical and numerical relationships between these solutions, which we believe to suggest that the relevant coupled nonlinear differential equations may be integrable exactly. 相似文献
13.
14.
J. C. Liang Z. B. Cai Y. Z. Sun L. Yi H. C. Wang 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,55(3):685-689
In this paper we answer the question: “what types of
spatial soliton can be formed based on two-photon-isomerisation (TPI)”. The
conclusion that anti-dark solitons are not supported by monotonic
nonlinearity should cast light on the notion of fundamental spatial
solitons. The idea to obtain a bright TPI soliton with the joining of a
background light or with the coupling of a dark soliton offers new schemes
of light-controlling-light. 相似文献
15.
《Physica D: Nonlinear Phenomena》1986,19(2):268-281
We show that discreteness effects which are known to exist for topological solitons exist also for non-topological kink solitons in nonlinear lattices. Extending the technique previously proposed for topological kinks we exhibit three cases where the properties of narrow kinks in nonlinear lattices are qualitatively different. Supersonic solitons in a monoatomic chain can propagate at constant speed without losing energy due to discreteness. Subsonic kinks in a monoatomic chain permanently radiate small amplitude oscillations. In a diatomic chain both supersonic and subsonic kinks lose energy due to discreteness. The characteristics of the small amplitude oscillations radiated by the kinks, when they exist, are well determined by our theoretical approach. Additional weak nonlinear effects are also described and discussed. 相似文献
16.
《Physics letters. [Part B]》1988,214(1):91-97
We show how Witten's topological Yang-Mills and gravitational quantum field theories may be obtained by a straightforward BRST gauge fixing procedure. We investigate some aspects of the renormalization of the topological Yang-Mills theory. It is found that the beta function for the Yang-Mills coupling constant is not zero. 相似文献
17.
J. Zhu 《Applied Physics A: Materials Science & Processing》2007,88(4):673-677
The local electric field components in the dielectric wall with a long gold nanowire in its core are calculated based on quasi-static
theory. The calculated results show that the complete polarized incident light does not only stimulate same directional complete
polarized local electric field. The same directional polarized electric field only locates close to the poles of the core
wire and is parallel or perpendicular to the polarized direction of the incident radiation. On the other hand, incident light
also stimulates perpendicular directional polarization, which densely locates close to the poles of the core wire in the direction
with an included angle π/4 or 3π/4 makes with polarization direction of incident light. Furthermore, local electric field
components in the wall also depend on the dielectric constant of dielectric wall and surrounding medium. When dielectric constant
of the wall is less than that of surrounding, the areas of perpendicular directional polarized local field in the wall reduce
and shift greatly. At the same time, more parallel directional polarized local field focus in the poles of the wall along
the incident polarization.
PACS 78.67.Bf; 73.20.Mf; 36.40.Gk; 78.66.Bz; 73.20.Mf 相似文献
18.
We describe a class of topological field theories called “balanced topological field theories”. These theories are associated
to moduli problems with vanishing virtual dimension and calculate the Euler character of various moduli spaces. We show that
these theories are closely related to the geometry and equivariant cohomology of “iterated superspaces” that carry two differentials.
We find the most general action for these theories, which turns out to define Morse theory on field space. We illustrate the
constructions with numerous examples. Finally, we relate these theories to topological sigma-models twisted using an isometry
of the target space.
Received: 2 September 1996 / Accepted: 3 October 1996 相似文献
19.
The Skyrme model is a classical field theory which has topological soliton solutions. These solitons are candidates for describing nuclei, with an identification between the numbers of solitons and nucleons. We have computed numerically, using two different minimization algorithms, minimum energy configurations for up to 22 solitons. We find, remarkably, that the solutions for seven or more solitons have nucleon density isosurfaces in the form of polyhedra made of hexagons and pentagons. Precisely these structures arise, though at the much larger molecular scale, in the chemistry of carbon shells, where they are known as fullerenes. 相似文献
20.
Jos D. Edelstein 《Physics letters. [Part B]》1997,390(1-4)
We study the cosmological constant problem in a three-dimensional N = 2 supergravity theory with gauge groupSU (2)global × U(1)local. The model we consider is known to admit string-like configurations, the so-called semi-local cosmic strings. We show that the stability of these solitonic solutions is provided by supersymmetry through the existence of a lower bound for the energy, even though the manifold of the Higgs vacuum does not contain non-contractible loops. Charged Killing spinors do exist over configurations that saturate the Bogomol'nyi bound, as a consequence of an Aharonov-Bohm-like effect. Nevertheless, there are no physical fermionic zero modes on these backgrounds. The exact vanishing of the cosmological constant does not imply, then, Bose-Fermi degeneracy. This provides a non-trivial example of the recent claim made by Witten on the vanishing of the cosmological constant in three dimensions without unphysical degeneracies. 相似文献