4 papers
Gravitational Waves from Primordial Black Holes formed by Null Energy Condition Violation during Inflation
Dong-Hui Yu, Jia-Zuo Zhang, Yong Cai
A transient violation of the null energy condition (NEC) during inflation provides a novel mechanism for producing primordial black holes (PBHs) and stochastic gravitational wave (…
Does Eternal Inflation Violate the Smeared Null Energy Condition?
Dong-Hui Yu, Yong Cai
The smeared null energy condition (SNEC) imposes a semilocal bound on the negative energy accumulated along null geodesics. In eternal inflation, rare stochastic upward fluctuation…
Constraints on Genesis Cosmology from the Smeared Null Energy Condition
Dong-Hui Yu, Mian Zhu, Yong Cai
The violation of the null energy condition (NEC) is essential for constructing nonsingular cosmological scenarios, such as Genesis cosmology, which avoids the initial singularity b…
Null energy condition violation and beyond Horndeski physics in light of DESI DR2 data
Gen Ye, Yong Cai
Inflation and dark energy (DE), both featuring accelerated expansion, are crucial components of modern cosmology. As indicated by singularity theorems, null energy condition (NEC)…