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arXiv · 1911.09689

On the Gauge Invariance of Cosmological Gravitational Waves

V. De Luca·G. Franciolini·A. Kehagias·A. Riotto
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Abstract

The issue of the gauge invariance of gravitational waves arises if they are produced in the early universe at second-order in perturbation theory. We address it by dividing the discussion about the gauge invariance in three parts: the production of gravitational waves, their propagation in the real universe, and their measurement.

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V. De Luca, G. Franciolini, A. Kehagias, A. Riotto. 2019-11-21. On the Gauge Invariance of Cosmological Gravitational Waves. https://doi.org/10.1088/1475-7516%2F2020%2F03%2F014

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