60 citations · 219 across the 12 of their papers we have counts for
12 papers
Correlated parity violation in gravity and electromagnetism from five-dimensional spacetime
Haomin Rao, Yunlong Zheng, Qi-Zhe Hou +2
Parity violation in the gravitational and electromagnetic sectors has been extensively investigated, yet the two are conventionally treated as independent phenomena. This separatio…
Inflation from entropy
Udaykrishna Thattarampilly, Yunlong Zheng
We investigate cosmological solutions for the modified gravity theory obtained from quantum relative entropy between the metric of spacetime and the metric induced by the geometry…
Extensions of two-field mimetic gravity
Yunlong Zheng, Haomin Rao
Two-field mimetic gravity was recently realized by looking at the singular limit of the conformal transformation between the auxiliary metric and the physical metric with two scala…
GRB 190829A -- A Showcase of Binary Late Evolution
Yu Wang, J. A. Rueda, R. Ruffini +7
GRB 190829A is the fourth closest gamma-ray burst (GRB) to date (). Owing to its wide range of radio, optical, X-ray, and the very-high-energy (VHE) observations by H.E.S…
Scalar and Tensor Perturbations in DHOST Bounce Cosmology
Mian Zhu, Amara Ilyas, Yunlong Zheng +2
We investigate the bounce realization in the framework of DHOST cosmology, focusing on the relation with observables. We perform a detailed analysis of the scalar and tensor pertur…
Emergent Universe and Genesis from the DHOST Cosmology
Amara Ilyas, Mian Zhu, Yunlong Zheng +1
In this article, we present an emergent universe scenario that can be derived from DHOST cosmology. The universe starts asymptotically Minkowski in the far past just like the regul…
Two-field mimetic gravity revisited and Hamiltonian analysis
Liuyuan Shen, Yunlong Zheng, Mingzhe Li
We revisit the two-field mimetic gravity model with shift symmetries recently proposed in the literature, especially the problems of degrees of freedom and stabilities. We first st…
Hamiltonian analysis of Mimetic gravity with higher derivatives
Yunlong Zheng
Two types of mimetic gravity models with higher derivatives of the mimetic field are analyzed in the Hamiltonian formalism. For the first type of mimetic gravity, the Ricci scalar…
Conformal invariant cosmological perturbations via the covariant approach: multicomponent universe
Yunlong Zheng, Yicen Mou, Haomin Rao +1
In recent years there has been a lot of interest in discussing frame dependences/independences of the cosmological perturbations under the conformal transformations. This problem h…
Direct couplings of mimetic dark matter and their cosmological effects
Liuyuan Shen, Yicen Mou, Yunlong Zheng +1
The original mimetic model was proposed to take the role of dark matter. In this paper we consider possible direct interactions of the mimetic dark matter with other matter in the…
On (in)stabilities of perturbations in mimetic models with higher derivatives
Yunlong Zheng, Liuyuan Shen, Yicen Mou +1
Usually when applying the mimetic model to the early universe, higher derivative terms are needed to promote the mimetic field to be dynamical. However such models suffer from the…
Constraints on the ultracompact minihalos using neutrino signals from the gravitino dark matter decay
Yun-Long Zheng, Yu-Peng Yang, Ming-Zhe Li +1
Ultracompact dark matter minihalos (UCMHs) would be formed during the earlier universe if there were large density perturbations. If the dark matter can decay into the standard mod…