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35 papers found.
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BPS Alice strings

When a charged particle encircles around an Alice string, it changes the sign of the electric charge. In this paper we find a BPS-saturated Alice string in U(1)×SO(3) gauge theory with charged complex scalar fields belonging to the vector representation. After performing BPS completion we solve the BPS equations numerically. We further embed the Alice string into an \( \mathcal{N} ...

A higher-order Skyrme model

We propose a higher-order Skyrme model with derivative terms of eighth, tenth and twelfth order. Our construction yields simple and easy-to-interpret higher-order Lagrangians. We first show that a Skyrmion with higher-order terms proposed by Marleau has an instability in the form of a baby-Skyrmion string, while the static energies of our construction are positive definite, ...

Some exact Bradlow vortex solutions

We consider the Bradlow equation for vortices which was recently found by Manton and find a two-parameter class of analytic solutions in closed form on nontrivial geometries with non-constant curvature. The general solution to our class of metrics is given by a hypergeometric function and the area of the vortex domain by the Gaussian hypergeometric function.

Topological solitons in the supersymmetric Skyrme model

A supersymmetric extension of the Skyrme model was obtained recently, which consists of only the Skyrme term in the Nambu-Goldstone (pion) sector complemented by the same number of quasi-Nambu-Goldstone bosons. Scherk-Schwarz dimensional reduction yields a kinetic term in three or lower dimensions and a potential term in two dimensions, preserving supersymmetry. Euclidean solitons ...

Stabilizing semilocal strings by polarization

Semilocal strings are vortices in the extended Abelian-Higgs model with two complex Higgs scalar fields among which a global SU(2) symmetry acts. They are known to be stable (unstable against expansion) in type-I (II) superconductors, in which gauge field is heavier (lighter) than the Higgs scalar field. In this paper, we find that vortices can be stabilized in the whole parameter ...

Ghostbusters in higher derivative supersymmetric theories: who is afraid of propagating auxiliary fields?

We present for the first time a ghost-free higher-derivative chiral model with a propagating auxiliary F-term field (highest component of the chiral multiplet). We obtain this model by removing a ghost in a higher derivative chiral model, with Higgsing it in terms of an auxiliary vector superfield. Depending on the sign of the quadratic derivative term of the chiral superfield, the ...

Semilocal fractional instantons

We find semi-local fractional instantons of codimension four in Abelian and non-Abelian gauge theories coupled with scalar fields and the corresponding \( \mathbb{C}{P}^{N-1} \) and Grassmann sigma models at strong gauge coupling. They are 1/4 BPS states in super-symmetric theories with eight supercharges, carry fractional (half) instanton charges characterized by the fourth ...

Fractional instantons and bions in the principal chiral model on \( {\mathrm{\mathbb{R}}}^2\times {S}^1 \) with twisted boundary conditions

Bions are multiple fractional instanton configurations with zero instanton charge playing important roles in quantum field theories on a compactified space with a twisted boundary condition. We classify fractional instantons and bions in the SU(N) principal chiral model on \( {\mathrm{\mathbb{R}}}^2\times {S}^1 \) with twisted boundary conditions. We find that fractional instantons ...

Non-BPS exact solutions and their relation to bions in ℂ P N − 1 models

We investigate non-BPS exact solutions in ℂ P N − 1 sigma models on ℝ 1 × S 1 with twisted boundary conditions, by using the Din-Zakrzewski projection method. We focus on the relation of the non-BPS solutions to the ansatz of multi-instanton (bion)configurations and discuss their significance in the context of the resurgence theory. We find that the transition between seemingly ...

Instantons in Lifshitz field theories

BPS instantons are discussed in Lifshitz-type anisotropic field theories. We consider generalizations of the sigma model/Yang-Mills instantons in renormalizable higher dimensional models with the classical Lifshitz scaling invariance. In each model, BPS instanton equation takes the form of the gradient flow equations for “the superpotential” defining “the detailed balance ...

Fractional instantons and bions in the O(N) model with twisted boundary conditions

Recently, multiple fractional instanton configurations with zero instanton charge, called bions, have been revealed to play important roles in quantum field theories on compactified spacetime. In two dimensions, fractional instantons and bions have been extensively studied in the ℂP N−1 model and the Grassmann sigma model on ℝ1 × S 1 with the ℤ N symmetric twisted boundary ...

A supersymmetric Skyrme model

Construction of a supersymmetric extension of the Skyrme term was a long-standing problem because of the auxiliary field problem; that is, the auxiliary field may propagate and cannot be eliminated, and the problem of having fourth-order time derivative terms. In this paper, we construct for the first time a supersymmetric extension of the Skyrme term in four spacetime dimensions, ...

Gravitating BPS Skyrmions

The BPS Skyrme model has many exact analytic solutions in flat space. We generalize the model to a curved space or spacetime and find that the solutions can only be BPS for a constant time-time component of the metric tensor. We find exact solutions on the curved spaces: a 3-sphere and a 3-hyperboloid; and we further find an analytic gravitating Skyrmion on the 3-sphere. For the ...

Resurgence in sine-Gordon quantum mechanics: exact agreement between multi-instantons and uniform WKB

We compute multi-instanton amplitudes in the sine-Gordon quantum mechanics (periodic cosine potential) by integrating out quasi-moduli parameters corresponding to separations of instantons and anti-instantons. We propose an extension of Bogomolnyi-Zinn-Justin prescription for multi-instanton configurations and an appropriate subtraction scheme. We obtain the multi-instanton ...

2d partition function in Ω-background and vortex/instanton correspondence

We derive the exact vortex partition function in 2d \( \mathcal{N}=\left(2,2\right) \) gauge theory on the Ω-background, applying the localization scheme in the Higgs phase. We show that the partition function at a finite Ω-deformation parameter ϵ satisfies a system of differential equations, which can be interpreted as a quantized version of the twisted F-term equations ...

Classifying bions in Grassmann sigma models and non-Abelian gauge theories by D-branes

We classify bions in the Grassmann $Gr_{N_{\rm F},N_{\rm C}}$ sigma model (including the ${\mathbb C}P^{N_{\rm F}-1}$ model) on ${\mathbb R}^{1}\times S^{1}$ with twisted boundary conditions. We formulate these models as $U(N_{\rm C})$ gauge theories with $N_{\rm F}$ flavors in the fundamental representations. These theories can be promoted to supersymmetric gauge theories and, ...

Kelvin modes as Nambu–Goldstone modes along superfluid vortices and relativistic strings: Finite volume size effects

Michikazu Kobayashi 1 Muneto Nitta 0 Subject Index 0 Department of Physics, and Research and Education Center for Natural Sciences, Keio University , Hiyoshi 4-1-1, Yokohama, Kanagawa 223-8521

Quantum exact non-abelian vortices in non-relativistic theories

Non-Abelian vortices arise when a non-Abelian global symmetry is exact in the ground state but spontaneously broken in the vicinity of their cores. In this case, there appear (non-Abelian) Nambu-Goldstone (NG) modes confined and propagating along the vortex. In relativistic theories, the Coleman-Mermin-Wagner theorem forbids the existence of a spontaneous symmetry breaking, or a ...

Neutral bions in the \( \mathbb{C} \) P N −1 model

Tatsuhiro Misumi 0 Muneto Nitta 0 Norisuke Sakai 0 0 Department of Physics, and Research and Education Center for Natural Sciences, Keio University , Hiyoshi 4-1-1, Yokohama, Kanagawa 223-8521

Color magnetism in non-Abelian vortex matter

We propose color magnetism as a generalization of the ordinary Heisenberg (anti-)ferro magnets on a triangular lattice. Vortex matter consisting of an Abrikosov lattice of non-Abelian vortices with color magnetic fluxes shows a color ferro or anti-ferro magnetism, depending on the interaction among the vortex sites. A prime example is a non-Abelian vortex lattice in rotating dense ...