Abstract
A generic prediction of general relativity is that the cosmological linear density growth factor is scale independent. But in general, modified gravities do not preserve this signature. A scale dependent can cause time variation in gravitational potential at high redshifts and provides a new cosmological test of gravity, through early time integrated Sachs-Wolfe (ISW) effect-large scale structure (LSS) cross correlation. We demonstrate the power of this test for a class of gravity, with the form . Such gravity, even with degenerate expansion history to , can produce detectable ISW effect at and . Null-detection of such effect would constrain to be at confidence level. On the other hand, robust detection of ISW-LSS cross correlation at high will severely challenge general relativity.
- Received 8 November 2005
DOI:https://doi.org/10.1103/PhysRevD.73.123504
©2006 American Physical Society