Inflation in energy-momentum squared gravity in light of Planck2018
Department of Theoretical Physics, Faculty of Science, University of Mazandaran, P. O. Box 47416-95447, Babolsar, Iran
2 ICRANet-Mazandaran, University of Mazandaran, P. O. Box 47416-95447, Babolsar, Iran
Accepted: 10 May 2022
Published online: 16 May 2022
We study cosmological dynamics of the energy-momentum squared gravity. By adding the squared of the matter field’s energy-momentum tensor () to the Einstein–Hilbert action, we obtain the Einstein’s field equations and study the conservation law. We show that, the presence of term, breaks the conservation of the energy-momentum tensor of the matter fields. However, an effective energy-momentum tensor in this model is conserved in time. By considering the FRW metric as the background, we find the Friedmann equations and by which we explore the cosmological inflation in model. We perform a numerical analysis on the perturbation parameters and compare the results with Planck2018 different data sets at and CL, to obtain some constraints on the coupling parameter . We show that, for , the gravity is an observationally viable model of inflation.
© The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2022