10 citations · 11 across the 6 of their papers we have counts for
6 papers
Parity-violating spatially covariant gravity at total derivative order
Jin-Jian Song, Xian Gao
We extend the polynomial construction of parity-violating spatially covariant gravity (SCG) to total derivative order , where counts the tota…
Spatially covariant gravity with two degrees of freedom: A perturbative analysis up to cubic order
Yang Yu, Yu-Min Hu, Xian Gao
There has been considerable interest in constructing modified gravity theories that propagate only two degrees of freedom (DOFs), corresponding to the tensorial gravitational waves…
Interacting hypersurfaces and multiple scalar-tensor theories
Yang Yu, Zheng Chen, Yu-Min Hu +1
We propose a novel method to construct ghost-free multiple scalar-tensor theories. The key idea is to use the geometric quantities of hypersurfaces defined by the scalar fields, ra…
Parity-violating scalar-tensor theory and the Qi-Xiu
Yu-Min Hu, Xian Gao
We investigate the parity-violating scalar-tensor theory and pay special attention to terms that are free of the Ostrogradsky ghost in the unitary gauge, i.e., when the scalar fiel…
Spatially covariant gravity with nonmetricity
Yang Yu, Zheng Chen, Xian Gao
Scalar fields play an important role in constructing modified gravity theories. In the case of a single scalar field with timelike gradient, the corresponding Lagrangian in the uni…
The effective field theory approach to the strong coupling issue in gravity with a non-minimally coupled scalar field
Yu-Min Hu, Yang Yu, Yi-Fu Cai +1
The Hamiltonian analysis for gravity implies the existence of at least one scalar-type degree of freedom (DoF). However, this scalar DoF of gravity does not manifest…