41 citations · 108 across the 10 of their papers we have counts for
10 papers
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…
Background-dependent and classical correspondences between and gravity
Cheng Wu, Xin Ren, Yuhang Yang +2
and gravity are based on fundamentally different geometric frameworks, yet they exhibit many similar properties. This article provides a comprehensive summary and com…
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…
Lowering the strong coupling mode of modified teleparallel gravity theories
Yu-Min Hu, Bi-Chu Li, Yang Yu +3
We investigate the strong coupling problem in modified teleparallel gravity theories using the effective field theory (EFT) approach, demonstrating that it is possible to shift the…
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…
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…
The effective field theory approach to the strong coupling issue in gravity
Yu-Min Hu, Yaqi Zhao, Xin Ren +3
We investigate the scalar perturbations and the possible strong coupling issues of around a cosmological background, applying the effective field theory (EFT) approach. We r…
Covariant 3+1 correspondence of the spatially covariant gravity and the degeneracy conditions
Yu-Min Hu, Xian Gao
A necessary condition for a generally covariant scalar-tensor theory to be ghostfree is that it contains no extra degrees of freedom in the unitary gauge, in which the Lagrangian c…
Spatially covariant gravity with two degrees of freedom: perturbative analysis
Yu-Min Hu, Xian Gao
We revisit the problem of building the Lagrangian of a large class of metric theories that respect spatial covariance, which propagate at most two degrees of freedom and in particu…
Higher derivative scalar-tensor theory and spatially covariant gravity: the correspondence
Xian Gao, Yu-Min Hu
We investigate the correspondence between generally covariant higher derivative scalar-tensor theory and spatially covariant gravity theory. The building blocks are the scalar fiel…