saving newtonian potential in CAMB

Use of Cobaya. camb, CLASS, cosmomc, compilers, etc.
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Angela Chen
Posts: 24
Joined: January 11 2019
Affiliation: University of Michigan

saving newtonian potential in CAMB

Post by Angela Chen » May 01 2020

Hi all,

I wonder if there's an easy way to save the Newtonian potential for CAMB outputs? I know CAMB saves Weyl potential and Newtonian potential ~ Weyl potential but it's good to check after some extension model modifications.

Thanks,
Angela

Antony Lewis
Posts: 1941
Joined: September 23 2004
Affiliation: University of Sussex
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Re: saving newtonian potential in CAMB

Post by Antony Lewis » May 02 2020

You can output any variable using the built-in symbolic interpretation, e.g. see round box 28 at

https://camb.readthedocs.io/en/latest/ScalEqs.html

for an example.

Angela Chen
Posts: 24
Joined: January 11 2019
Affiliation: University of Michigan

Re: saving newtonian potential in CAMB

Post by Angela Chen » May 02 2020

Antony Lewis wrote:
May 02 2020
You can output any variable using the built-in symbolic interpretation, e.g. see round box 28 at

https://camb.readthedocs.io/en/latest/ScalEqs.html

for an example.
thanks Antony! But I need rather a way to save things in Fortran CAMB -- so an expression of newtonian potential in terms of the equation.f90 transfer variables would be very helpful. If I want to save k^2*Psi_N, is it k*sigma/adotoa+k*sigmadot?

Antony Lewis
Posts: 1941
Joined: September 23 2004
Affiliation: University of Sussex
Contact:

Re: saving newtonian potential in CAMB

Post by Antony Lewis » May 03 2020

I don't recall off hand, but you can use the camb_fortran() function (see notebook) to get equivalent fortran for symbolic expressions.

Angela Chen
Posts: 24
Joined: January 11 2019
Affiliation: University of Michigan

Re: saving newtonian potential in CAMB

Post by Angela Chen » May 04 2020

Thanks! looks like it is

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