- #1

- 222

- 9

## Main Question or Discussion Point

Based on the paper by Visinelli (https://arxiv.org/abs/1605.06449),

He stated in page 6 that the scalar spectral index as given by the Planck 2013 data (https://arxiv.org/abs/1303.5076) is,

##n_s = 0.9655 \pm 0.0062~~## (##68\%## C.L.)

but when I looked into the Planck 2013 paper, I did not see that constraint, so I tried to read the much later paper by the Planck team which is the Planck 2015 (arxiv.org/abs/1502.02114) and I saw it, also it is very strange for Visinelli to cite the 2013 results given that his paper had been published in 2016, so it makes more sense for him to cite the 2015 paper by the Planck team.

The problem is, he also stated in Figure 1. on page 13 that "the light blue band showed the ##95\%## confidence region" but he did not state any range for it unlike the ##68\%## above. I tried to search for it in the Planck 2013 and 2015 paper but I can't seem to find the range given by the Planck team for the ##95\%## confidence region. Can anyone help me with this?

Also, I noticed that in Visinelli's paper, equation (3.10) seems wrong, I think it should be ##n_s -1## instead of ##1-n_s## since if you try to compute for ##n_s## it would give an answer that is out of the range (far out). Any comment?

He stated in page 6 that the scalar spectral index as given by the Planck 2013 data (https://arxiv.org/abs/1303.5076) is,

##n_s = 0.9655 \pm 0.0062~~## (##68\%## C.L.)

but when I looked into the Planck 2013 paper, I did not see that constraint, so I tried to read the much later paper by the Planck team which is the Planck 2015 (arxiv.org/abs/1502.02114) and I saw it, also it is very strange for Visinelli to cite the 2013 results given that his paper had been published in 2016, so it makes more sense for him to cite the 2015 paper by the Planck team.

The problem is, he also stated in Figure 1. on page 13 that "the light blue band showed the ##95\%## confidence region" but he did not state any range for it unlike the ##68\%## above. I tried to search for it in the Planck 2013 and 2015 paper but I can't seem to find the range given by the Planck team for the ##95\%## confidence region. Can anyone help me with this?

Also, I noticed that in Visinelli's paper, equation (3.10) seems wrong, I think it should be ##n_s -1## instead of ##1-n_s## since if you try to compute for ##n_s## it would give an answer that is out of the range (far out). Any comment?