After a historical introduction to Poisson’s equation for Newtonian gravity, its analog for static gravitational fields in Einstein’s theory is reviewed. It appears that the pressure contribution to the active mass density in Einstein’s theory might also be noticeable at the Newtonian level. A form of its surprising appearance, first noticed by Richard Chase Tolman, was discussed half a century...

We present a physical analogy which can be used to understand the issues involved in the Principle of Equivalence in so-called spatial flow theories of gravity, and we discuss the essential kinematic properties of the flow which distinguish its gravitational, non-inertial, and inertial modes. We also point out that the acceleration experienced by a body moving in the flow does not always coinci...

A theoretical investigation has been made of two new ultra-low-frequency electrostatic modes, namely, dust-cyclotron mode and dust-lower-hybrid mode, propagating perpendicular to the external magnetic field, in a self-gravitating magnetized two fluid dusty plasma system. It has been shown that the effect of the self-gravitational force, acting on both dust grains and ions, significantly modifie...

Extreme-mass-ratio inspirals (EMRIs) will be key sources for LISA. However, accurately extracting system parameters from a detected EMRI waveform require self-force calculations at second order in perturbation theory, which are still nascent stage. One major obstacle these is the strong divergences that encountered on worldline of small object. Previously, it was shown by one us [Phys. Rev. D 9...