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arXiv · 1512.02947

On the Green and Wald formalism

Jan J. Ostrowski·Boudewijn F. Roukema
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Abstract

Backreaction in the cosmological context is a longstanding problem that is especially important in the present era of precise cosmology. The standard model of a homogeneous background plus density perturbations is most probably oversimplified and is expected to fail to fully account for the near-future observations of sub-percent precision. From a theoretical point of view, the problem of backreaction is very complicated and deserves careful examination. Recently, Green and Wald claimed in a series of papers to have developed a formalism to properly describe the influence of density inhomogeneities on average properties of the Universe, i.e., the backreaction effect. A brief discussion of this framework is presented, focussing on its drawbacks and on misconceptions that have arisen during the "backreaction debate".

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Jan J. Ostrowski, Boudewijn F. Roukema. 2015-12-09. On the Green and Wald formalism. https://doi.org/10.1142/9789813226609_0264

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