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Causality and the Doppler Peaks

Neil Turok
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Abstract

Could cosmic structure have formed by the action of causal physics within the standard hot big bang, or was a prior period of inflation required? Recently there has been some discussion of whether causal sources could reproduce the pattern of Doppler peaks of the standard scale-invariant adiabatic theory. This paper gives a rigorous definition of causality, and a causal decomposition of a general source. I present an example of a simple causal source which mimics the standard adiabatic theory, accurately reproducing the behaviour of the local intrinsic temperature perturbations.

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Neil Turok. 1996-07-26. Causality and the Doppler Peaks. https://doi.org/10.1103/physrevd.54.r3686

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