64 citations · 112 across the 10 of their papers we have counts for
10 papers
Constraints on Coupled Dark Energy in the DESI Era
Adrià Gómez-Valent, Ziyang Zheng, Luca Amendola
We investigate the current viability of a well-known coupled dark energy scenario in which cold dark matter (DM) interacts with a spin-0 dark energy component through a non-trivial…
Testing the cosmological Euler equation: viscosity, equivalence principle, and gravity beyond general relativity
Ziyang Zheng, Malte Schneider, Luca Amendola
We investigate how the cosmological Euler equation can be tested in the presence of viscous dark matter, violations of the equivalence principle (EP), and modifications of gravity,…
One-loop kernels in scale-dependent Horndeski theory
Ziyang Zheng, Hanqiong Jia, Bilal Tüdes +3
We investigate the nonlinear evolution of cosmological perturbations in theories with scale-dependent perturbation growth, first in general and then focusing on Horndeski gravity.…
Model-independent forecasts for the cosmological anisotropic stress
Ziad Sakr, Ziyang Zheng, Santiago Casas
The effective anisotropic stress is a key variable in the characterization of many classes of modified gravity theories, as it allows the testing for a long-range force additio…
Testing the equivalence principle across the Universe: a model-independent approach with galaxy multi-tracing
Sveva Castello, Ziyang Zheng, Camille Bonvin +1
We present a test of the equivalence principle on cosmological scales. This cornerstone of general relativity has been tested with high precision for standard matter, but its valid…
Testing the cosmological Poisson equation in a model-independent way
Ziyang Zheng, Ziad Sakr, Luca Amendola
We show how one can test the cosmological Poisson equation by requiring only the validity of three main assumptions: the energy-momentum conservation equations of matter, the equiv…
Coupled and uncoupled early dark energy, massive neutrinos and the cosmological tensions
Adrià Gómez-Valent, Ziyang Zheng, Luca Amendola +2
Some cosmological models with non-negligible dark energy fractions in particular windows of the pre-recombination epoch are capable of alleviating the Hubble tension quite efficien…
Early dark energy in the pre- and post-recombination epochs
Adrià Gómez-Valent, Ziyang Zheng, Luca Amendola +2
Many quintessence models possess scaling or attractor solutions where the fraction of dark energy follows the dominant component in previous epochs of the expansion, or phase trans…
Extremal rotating black holes, scalar perturbation and superradiant stability
Jia-Mao Lin, Ming-Jian Luo, Zi-Han Zheng +2
A (charged) rotating black hole may be unstable against a (charged) massive scalar field perturbation due to the existence of superradiance modes. The stability property depends on…
Analytic study of superradiant stability of Kerr-Newman black holes under charged massive scalar perturbation
Jun-Huai Xu, Zi-Han Zheng, Ming-Jian Luo +1
The superradiant stability of a Kerr-Newman black hole and charged massive scalar perturbation is investigated. We treat the black hole as a background geometry and study the equat…