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16 papers found.
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Ghostbusters in f (R) supergravity

Abstract f (R) supergravity is known to contain a ghost mode associated with higher-derivative terms if it contains R n with n greater than two. We remove the ghost in f (R) supergravity by introducing auxiliary gauge field to absorb the ghost. We dub this method as the ghostbuster mechanism [1]. We show that the mechanism removes the ghost super-multiplet but also terms...

Ghost-free vector superfield actions in supersymmetric higher-derivative theories

We systematically construct ghost-free higher-derivative actions of Abelian vector supermultiplets in four-dimensional \( \mathcal{N}=1 \) global supersymmetric theories. After giving a simple example which illustrates that a naive introduction of a higher-derivative term gives rise to a ghost, we discuss possible building blocks for a ghost-free action and explicitly show that...

Large-N ℂP N − 1 sigma model on a finite interval

We analyze the two-dimensional ℂP N − 1 sigma model defined on a finite space interval L, with various boundary conditions, in the large N limit. With the Dirichlet boundary condition at the both ends, we show that the system has a unique phase, which smoothly approaches in the large L limit the standard 2D ℂP N − 1 sigma model in confinement phase, with a constant mass generated...

Small winding-number expansion: vortex solutions at critical coupling

We study an axially symmetric solution of a vortex in the Abelian-Higgs model at critical coupling in detail. Here we propose a new idea for a perturbative expansion of a solution, where the winding number of a vortex is naturally extended to be a real number and the solution is expanded with respect to it around its origin. We test this idea on three typical constants contained...

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

AbstractWe 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...

Cosmic R-string in thermal history

Abstract We study stabilization of an unstable cosmic string associated with spontaneously broken U(1) R symmetry, which otherwise causes a dangerous roll-over process. We demonstrate that in a gauge mediation model, messengers can receive enough corrections from the thermal plasma of the supersymmetric standard model particles to stabilize the unstable modes of the string.

Cosmic R-string, R-tube and vacuum instability

We show that a cosmic string associated with spontaneous U(1) R symmetry breaking gives a constraint for supersymmetric model building. In some models, the string can be viewed as a tube-like domain wall with a winding number interpolating a false vacuum and a true vacuum. Such string causes inhomogeneous decay of the false vacuum to the true vacuum via rapid expansion of the...

Higher Derivative Corrections to Non-Abelian Vortex Effective Theory

We give a systematic method to calculate higher derivative corrections to low-energy effective theories of solitons, which are in general nonlinear sigma models on the moduli spaces of the solitons. By applying it to the effective theory of a single BPS non-Abelian vortex in U(N) gauge theory with N fundamental Higgs fields, we obtain four-derivative corrections to the effective...

Supersymmetric Completion of an R2 Term in Five-Dimensional Supergravity

We analyze the structure of a particular higher derivative correction of five-dimensional ungauged and gauged supergravity with eight supercharges. Specifically, we determine all the purely bosonic terms which are connected by the supersymmetry transformation to the mixed gauge-gravitational Chern-Simons term, W ∧ tr R ∧ R. Our construction utilizes the superconformal formulation...

Gauge and Non-Gauge Tensor Multiplets in 5D Conformal Supergravity

Taichiro Kugo 0 Keisuke Ohashi 0 0 Department of Physics, Kyoto University , Kyoto 606-8502, Japan An off-shell formulation of two distinct tensor multiplets, a massive tensor multiplet and a tensor

Superconformal Tensor Calculus on an Orbifold in 5D

Taichiro Kugo 0 Keisuke Ohashi 0 0 Department of Physics, Kyoto University , Kyoto 606-8502, Japan Superconformal tensor calculus on an orbifold S1/Z2 is given in five-dimensional (5D) spacetime

Superconformal Tensor Calculus in Five Dimensions

Tomoyuki Fujita 0 Keisuke Ohashi 0 0 Department of Physics, Kyoto University , Kyoto 606-8502, Japan We present a full superconformal tensor calculus in five spacetime dimensions in which the Weyl

Off-Shell d=5 Supergravity Coupled to a Matter-Yang-Mills System

We present an off-shell formulation of a matter-Yang-Mills system coupled to supergravity in five-dimensional space-time. We give an invariant action for a general system of vector multiplets and hypermultiplets coupled to supergravity as well as the supersymmetry transformation rules. All the auxiliary fields are retained, so that the supersymmetry transformation rules remain...

Supergravity Tensor Calculus in 5D from 6D

Taichiro Kugo 0 Keisuke Ohashi 0 0 Department of Physics, Kyoto University , Kyoto 606-8502, Japan Supergravity tensor calculus in five spacetime dimensions is derived by dimensional reductionfrom

Off-Shell Formulation of Supergravity on an Orbifold

Tomoyuki Fujita 0 ) Taichiro Kugo 0 Keisuke Ohashi 0 0 Department of Physics, Kyoto University , Kyoto 606-8502, Japan An off-shell formulation is given for the supersymmetry in singular spaces that