Physical Evidence for Dark Energy

R. Scranton; A. J. Connolly; R. C. Nichol; A. Stebbins; I. Szapudi; D. J. Eisenstein; N. Afshordi; T. Budavari; I. Csabai; J. A. Frieman; J. E. Gunn; D. Johnston; Y. Loh; R. H. Lupton; C. J. Miller; E. S. Sheldon; R. S. Sheth; A. S. Szalay; M. Tegmark; Y. Xu

arXiv · astro-ph/0307335

Physical Evidence for Dark Energy

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Abstract

We present measurements of the angular cross-correlation between luminous red galaxies from the Sloan Digital Sky Survey and the cosmic microwave background temperature maps from the Wilkinson Microwave Anisotropy Probe. We find a statistically significant achromatic positive correlation between these two data sets, which is consistent with the expected signal from the late Integrated Sachs-Wolfe (ISW) effect. We do not detect any anti-correlation on small angular scales as would be produced from a large Sunyaev-Zel'dovich (SZ) effect, although we do see evidence for some SZ effect for our highest redshift samples. Assuming a flat universe, our preliminary detection of the ISW effect provides independent physical evidence for the existence of dark energy.

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R. Scranton, A. J. Connolly, R. C. Nichol, A. Stebbins, I. Szapudi, D. J. Eisenstein, N. Afshordi, T. Budavari, I. Csabai, J. A. Frieman, J. E. Gunn, D. Johnston, Y. Loh, R. H. Lupton, C. J. Miller, E. S. Sheldon, R. S. Sheth, A. S. Szalay, M. Tegmark, Y. Xu. 2003-07-20. Physical Evidence for Dark Energy. https://arxiv.org/abs/astro-ph/0307335

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