214 citations · 274 across the 5 of their papers we have counts for
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The universe as a black hole in isotropic coordinates
Nikodem J. Poplawski
We show that the radial geodesic motion of a particle inside a black hole in isotropic coordinates (the Einstein-Rosen bridge) is physically different from the radial motion inside…
A variational formulation of relativistic hydrodynamics
Nikodem J. Poplawski
We combine Taub's and Ray's variational approaches to relativistic hydrodynamics of perfect fluids into another simple formulation.
The cosmic snap parameter in f(R) gravity
Nikodem J. Poplawski
We derive the expression for the snap parameter in f(R) gravity. We use the Palatini variational principle to obtain the field equations and regard the Einstein conformal frame as…
On the nonsymmetric purely affine gravity
Nikodem J. Poplawski
We review the vacuum purely affine gravity with the nonsymmetric connection and metric. We also examine dynamical effects of the second Ricci tensor and covariant second-rank tenso…
A Lagrangian description of interacting dark energy
Nikodem J. Poplawski
We propose a relativistically covariant model of interacting dark energy based on the principle of least action. The cosmological term in the gravitational Lagrangian is a func…