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arXiv · 2102.02098

Lost in the Log-Polynomial Expansion: Comment on arXiv:2101.08278

Aritra Banerjee·Eoin Ó Colgáin·Misao Sasaki·M. M. Sheikh-Jabbari
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Abstract

In [1] we highlighted the fact that the log polynomial expansion employed in Nature Astron. 3, no.3, 272-277 (2019) [2] is a poor approximation to flat $\Lambda$CDM, so using it to infer deviations from flat $\Lambda$CDM is not well-motivated. The "orthogonalized logarithmic polynomials" recently presented in arXiv:2101.08278 [3] are an attempt to respond to the earlier criticism [1]. Here we demonstrate that this new technique [3] - interesting though it may be - fails to address the fundamental problem raised in [1]. Unfortunately, the claim made in [2] may still be lost in the expansion.

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Aritra Banerjee, Eoin Ó Colgáin, Misao Sasaki, M. M. Sheikh-Jabbari. 2021-02-03. Lost in the Log-Polynomial Expansion: Comment on arXiv:2101.08278. https://arxiv.org/abs/2102.02098

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