Parameterized Post-Friedmann Formalism for the Dark Scattering Model
DOI:
https://doi.org/10.2218/esjs.10094Keywords:
Parameterized Post-Friedmann, Dark Energy, Dark Matter, S8 Tension, Dark Scattering ModelAbstract
Recent results from the Dark Energy Spectroscopic Instrument find a preference for dynamical dark energy. This motivates improving the accuracy of predictions for dynamical dark energy models, including those which can resolve current tensions in the data, such as the dark scattering model. We improve the parameterized post-Friedmann approach for this model, reducing the error from approximately 1.3% to only 0.1%. Additionally, we show that the commonly used scale-independent approximation may not be completely accurate and, when applying the best-fit values from DESI on the dark scattering model, we predict an enhancement of the power spectrum at late times, worsening the S8 tension.
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Copyright (c) 2025 Durrah Alessa, Dr. Pedro Carrilho
This work is licensed under a Creative Commons Attribution 4.0 International License.
