8 papers
Inflation on the lattice: scalar Gauss-Bonnet single field inflation
Fei-Yu Chen, Jing-Zhi Zhou, Zhi-Chao Li +1
We use lattice methods to study inflation in the scalar Gauss-Bonnet (SGB) gravity theory. We focus on the ultra-slow-roll scenario with the peak frequency falls into the PTA band.…
Lorentz-Violating (Regular) Black Holes in Einstein Gravity
Zhi-Chao Li, H. Lu
We introduce a minimally coupled dark sector based on a nonlinear electrodynamics to generate regular spacetime textures that interpolate from a regular core to an asymptotic Loren…
When Bumblebee Meets NLED: Lorentz-Violating Black Holes and Regular Spacetimes
Zhi-Chao Li, H. Lu
We construct charged black hole solutions in bumblebee gravity coupled to a general class of nonlinear electrodynamics (NLED) using an auxiliary Maxwell-scalar formalism. The norm-…
Matter Maps to Geometry in Gravitational Collapse
H. Khodabakhshi, Zhi-Chao Li, H. Lu +1
We establish an exact bidirectional map between the effective homogeneous interior density of a collapsing star and the exterior metric function in generalized Oppenheimer--Snyder…
Tensor induced gravitational waves
Fei-Yu Chen, Jing-Zhi Zhou, Di Wu +2
Primordial gravitational waves on small scales are not tightly constrained by current cosmological observations, which allows for the possibility of large amplitudes at small scale…
Probing small-scale primordial power spectra with induced gravitational waves
Di Wu, Zhi-Chao Li, Peng-Yu Wu +2
Large-scale primordial perturbations have been well constrained by current cosmological observations, but the properties of small-scale perturbations remain elusive. This study foc…