arXiv subjects

Yong Hae Ko

Publications and source records attributed to Yong Hae Ko.

3 recordsLinked to original sources

arXiv2019

Quantum consistency in supersymmetric theories with $R$-symmetry in curved space

We discuss consistency at the quantum level in the rigid $\mathcal N=1$ supersymmetric field theories with a $U(1)_R$ symmetry in four-dimensional curved space which are formulated via coupling to the new-minimal supergravity background fields. By analyzing correlation functions of the current operators in the $\mathcal{R}$-multiplet, we show that the quantum consistency with the (unbroken) supersymmetry requires the $U(1)_R$ anomaly coefficient, which depends only on the field content of the theory, to vanish. This consistency condition is obtained under the assumption that the supercurrent Ward identity is non-anomalous and that the vacuum is supersymmetric.

hep-th↗

arXiv2018

Super-Weyl Anomaly from Holography and Rigid Supersymmetry Algebra on Two-Sphere

Operators transform anomalously under the symmetry in the presence of quantum anomalies. We study this aspect of the super-Weyl anomaly in $\mathcal N=(1,1)$ superconformal field theories (SCFTs), in the context of AdS/CFT. In particular, we carry out holographic renormalization for $(1,1)$ pure AdS$_3$ supergravity that is supposed to be a gravity dual of the $\mathcal N=(1,1)$ SCFT, and derive holographic superconformal Ward identities with corresponding anomalies. We show that the obtained super-Weyl anomaly of the $\mathcal N=(1,1)$ SCFT induces a quantum correction term in the transformation law of the supercurrent under the rigid supersymmetry. We demonstrate that the correction term does not affect the $\mathcal N=(1,1)$ rigid supersymmetry algebra on two-sphere.

hep-th↗

arXiv2015

Scalar - Tensor gravity with scalar -matter direct coupling and its cosmological probe

SNIA and CMB datasets have shown both of evolving Newton's "constant" and a signature of the coupling of scalar field to matter. These observations motivate the consideration of the scalar-matter coupling in Jordan frame in the framework of scalar-tensor gravity. So far, majority of the works on the coupling of scalar matter has performed in Einstein frame in the framework of minimally coupled scalar fields. In this work, we generalize the original scalar-tensor theories of gravity introducing a direct coupling of scalar to matter in the Jordan frame. The combined consideration of both evolving Newton's constant and scalar-matter coupling using the recent observation datasets, shows features different from the previous works. The analysis shows a vivid signature of the scalar-matter coupling. The variation rate of the Newton's constant is obtained rather greater than that determined in the previous works.

astro-ph.CO↗