5 papers
Covariant scalar-tensor theories beyond second derivatives
Mohammad Ali Gorji, Pavel Petrov, Karim Noui
We propose a covariant, gauge-independent construction of foliation-based scalar-tensor theories, yielding diffeomorphism-invariant operators involving only gradients on the hypers…
Bounds on Gravitational Wave Production from Unitarity in an Early NEC-Violating Model
Pavel Petrov, Jianing Wang
We study a cosmological scenario featuring an early phase of null energy condition (NEC) violation. Within this framework, we show that perturbative unitarity bounds place strong c…
Abelian and non-Abelian mimetic black holes
Mohammad Ali Gorji, Susmita Jana, Pavel Petrov
We investigate black hole solutions in the mimetic extension of the Einstein-Yang-Mills system, in which the Yang-Mills term is constrained to be constant. In the Abelian U(1) case…
Linear Higher-Order Maxwell-Einstein-Scalar Theories
Mohammad Ali Gorji, Shinji Mukohyama, Pavel Petrov +1
In the context of the Higher-Order Maxwell-Einstein-Scalar (HOMES) theories, which are invariant under spacetime diffeomorphisms and gauge symmetry, we study two broad subcl…
Genesis--Starobinsky inflation can explain the ACT data
Han Gil Choi, Pavel Petrov, Seong Chan Park
We propose a novel non-singular cosmological scenario within the framework of Horndeski gravity, consisting of three successive stages: (i) a Genesis phase, in which the Universe s…