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Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

2009

Dartmouth College

Cosmological constant

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Full-Text Articles in Physical Sciences and Mathematics

Effects Of Gravitational Slip On The Higher-Order Moments Of The Matter Distribution, Scott F. Daniel Oct 2009

Effects Of Gravitational Slip On The Higher-Order Moments Of The Matter Distribution, Scott F. Daniel

Dartmouth Scholarship

Cosmological departures from general relativity offer a possible explanation for the cosmic acceleration. To linear order, these departures (quantified by the model-independent parameter ϖ, referred to as a “gravitational slip”) amplify or suppress the growth of structure in the universe relative to what we would expect to see from a general relativistic universe lately dominated by a cosmological constant. As structures collapse and become more dense, linear perturbation theory is an inadequate descriptor of their behavior, and one must extend calculations to nonlinear order. If the effects of gravitational slip extend to these higher orders, we might expect to see …


Multiparameter Investigation Of Gravitational Slip, Scott F. Daniel, Robert R. Caldwell, Asantha Cooray, Paolo Serra, Alessandro Melchiorri Jul 2009

Multiparameter Investigation Of Gravitational Slip, Scott F. Daniel, Robert R. Caldwell, Asantha Cooray, Paolo Serra, Alessandro Melchiorri

Dartmouth Scholarship

A detailed analysis of gravitational slip, a new post-general relativity cosmological parameter characterizing the degree of departure of the laws of gravitation from general relativity on cosmological scales, is presented. This phenomenological approach assumes that cosmic acceleration is due to new gravitational effects; the amount of spacetime curvature produced per unit mass is changed in such a way that a universe containing only matter and radiation begins to accelerate as if under the influence of a cosmological constant. Changes in the law of gravitation are further manifest in the behavior of the inhomogeneous gravitational field, as reflected in the cosmic …