3 papers
gr-qc2026
Degrees of freedom of a quadratic scalar-nonmetricity theory
Jia-Jun Chen, Zheng Chen, Xian Gao
We study the number of degrees of freedom (DOFs) in quadratic scalar-nonmetricity (QSN) theory, whose Lagrangian is the linear combination of five quadratic nonmetricity invariants…
gr-qc2024
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…
gr-qc2024
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…