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General relativistic analysis of peculiar velocities

George F R Ellis·Henk van Elst·Roy Maartens
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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.

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George F R Ellis, Henk van Elst, Roy Maartens. 2001-09-12. General relativistic analysis of peculiar velocities. https://doi.org/10.1088/0264-9381%2F18%2F23%2F308

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