3 papers
gr-qc2026
Non-minimal Effective Scalar-Tensor Gravity in the Early Universe
Oleg Zenin, Roman Stamov, Sergey Kuzmin +1
We study the consistency of several early-Universe scenarios within a framework of non-minimal effective sca\-lar--ten\-sor gravity. We show that bounce, inflation, and genesis sta…
gr-qc2025
Constraints of extended gravity theory in the regime of Universe accelerated extension: turnaround radius
Oleg Zenin, Stanislav Alexeyev
Applying the definition of the turnaround radius and the fact that the best agreement with observational data on extragalactic scales is currently provided by general relativity wi…
gr-qc2025
Black Hole Shadows Modelling in Extended gravity: Rotation Accounting and coupled effects
Stanislav Alexeyev, Oleg Zenin, Artem Baiderin
Using an improved version of the Newman-Janis algorithm, we obtain metrics of rotating black holes for a set of extended gravity theories that extend general relativity in differen…