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arXiv · 1907.03606

Cosmological Number Counts in Einstein and Jordan frames

Jérémie Francfort·Basundhara Ghosh·Ruth Durrer
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Abstract

Even though we know that physical observations are frame independent, the frame dependence of cosmological perturbations is relatively subtle and has led to confusion in the past. In this paper we show that while the (unobservable) matter power spectrum is frame dependent, the observable number counts are not. We shall also determine how the frame dependence of the power spectrum depends on scale.

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Jérémie Francfort, Basundhara Ghosh, Ruth Durrer. 2019-07-08. Cosmological Number Counts in Einstein and Jordan frames. https://doi.org/10.1088/1475-7516%2F2019%2F09%2F071

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