arXiv subjects

Jonghee Kang

Publications and source records attributed to Jonghee Kang.

3 recordsLinked to original sources

arXiv2019

Gauged Galileons

We discuss the gauging of non-linearly realized symmetries as a method to systematically construct spontaneously broken gauge theories. We focus in particular on galileon fields and, using a coset construction, we show how to recover massive gravity by gauging the galileon symmetry. We then extend our procedure to the special galileon, and obtain a theory that couples a massive spin-2 field with a traceless symmetric field, and is free of pathologies at quadratic order around flat space.

hep-th↗

arXiv2018

Anisotropic tensor modes from icosahedral inflation

For icosahedral inflation, we compute the tensor modes' two-point function in the presence of higher derivative corrections, and show that in general this features anisotropies that are aligned with the underlying icosahedral structure. The effect is small within the regime of validity of the effective theory, but it is the leading contribution to a mixed correlator between the two different helicities. We also estimate the magnitude of a similar effect for a mixed scalar-tensor correlator, whose detailed computation we leave for future work. Along the way, we clarify a number of aspects of the spin decomposition of generic icosahedral-invariant physical quantities.

hep-th↗

arXiv2015

Platonic solids back in the sky: Icosahedral inflation

We generalize the model of solid inflation to an anisotropic cosmic solid. Barring fine tunings, the observed isotropy of the cosmological background and of the scalar two-point function isolate the icosahedral group as the only possible symmetry group of such a solid. In such a case, higher-point correlation functions---starting with the three-point one---are naturally maximally anisotropic, which makes the standard detection strategies highly inefficient and calls for a dedicated analysis of CMB data. The tensor two-point function can also be highly anisotropic, but only in the presence of sizable higher-derivative couplings.

hep-th↗