- #1

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- 152

- Summary:
- I am trying to understand why the simple inflationary model with potential ##V(\phi) \propto \phi^2## is disfavored compared to models predicting a smaller tensor-to-scalar ratio.

I am reading Planck 2015 results. In particular, I focused on "Power law potentials" subsection.

The issues I have are

1. I do not understand why the validity of the model can be determined by the value of the ##B## mode.

2. Why the ##B## mode values ##\ln B = −11.6## and ##\ln B = −23.3## for the cubic and quartic potentials , respectively, are regarded as "strongly disfavored" and ##\ln B = −4.7## for the quadratic potential as "moderately disfavored"? What I mean is: what is the threshold value at which we can consider the potential as favored and why?

Thank you!

The issues I have are

1. I do not understand why the validity of the model can be determined by the value of the ##B## mode.

2. Why the ##B## mode values ##\ln B = −11.6## and ##\ln B = −23.3## for the cubic and quartic potentials , respectively, are regarded as "strongly disfavored" and ##\ln B = −4.7## for the quadratic potential as "moderately disfavored"? What I mean is: what is the threshold value at which we can consider the potential as favored and why?

Thank you!