General relativistic analysis of peculiar velocities

Abstract

Abstract. We give a careful general relativistic and (1+3)-covariant analysis of cosmological peculiar velocities induced by matter density perturbations in the presence of a cosmological constant. In our quasi-Newtonian approach, constraint equations arise to maintain zero shear of the non-comoving fundamental worldlines which define a Newtonian-like frame, and these lead to the (1+3)-covariant dynamical equations, including a generalized Poisson-type equation. We investigate the relation between peculiar velocity and peculiar acceleration, finding the conditions under which they are aligned. In this case we find (1+3)-covariant relativistic generalizations of well-known Newtonian results.PACS numbers: 98.80.Hw, 98.65.Dx, 95.30.Sf

Light propagation and the average expansion rate in near-FRW universes

“…Nevertheless, if we assume that the observer moves along a geodesic (which is the realistic case in the late universe), the smallness of the deviation of u α follows from the assumptions about metric perturbations and their derivatives. It would be useful to have a definition of the peculiar velocity that would be valid in a general cosmological spacetime [51] and that would correspond to the observational use of the term, so that the observed smallness of this quantity could be used as an input.…”

“…In linear theory and in the Poisson gauge, it is simple to identify u i as the physical velocity around the mean flow. However, defining the peculiar velocity in a more general context and translating the observational constraint into a well-defined mathematical statement is not straightforward [49,51].…”

Supersymmetry status and phenomenology at the Large Hadron Collider

“…4. The A-annihilation funnel, which occurs at very large values of tan β ∼ 45-60 [22][23][24][25][26][27]. In this case, one has m A ∼ 2m Z1 .…”

Relativistic approach to the kinematics of large-scale peculiar motions

“…The subject has a fairly long research history that goes back several decades. Nevertheless, although there are many structure-formation studies that incorporate peculiar velocities, essentially all the work that focuses on the evolution of the peculiar-velocity field is Newtonian, or quasi-Newtonian, in nature (see [2][3][4] and [5,6] respectively). In addition, to the best of our knowledge, all these studies are conducted in the rest-frame of the smooth Hubble expansion.…”