Using CAMB for closed FLRW model with power spectrum in spherical wave numbers

Use of Healpix, camb, CLASS, cosmomc, compilers, etc.
Post Reply
Brajesh Gupt
Posts: 6
Joined: January 04 2015
Affiliation: Pennsylvania State University

Using CAMB for closed FLRW model with power spectrum in sphe

Post by Brajesh Gupt » February 18 2016

I am trying to compute evolve the initial power spectrum at the end of inflation to the CMB in closed model with S^3 topology. The initial power spectrum is as a function of spherical wavenumbers (n) which is discrete, but the CAMB code requires giving input in (k) which is a continuous variable. Is there a way to implement that?

Or, can I just convert 'n' to 'k' and use interpolation to find the missing k's? But, this would introduce some numerical errors because Cl's are now obtained from a discrete sum rather than an integral in k.

Any insight will be very helpful.

Thanks,
Brajesh

Antony Lewis
Posts: 1547
Joined: September 23 2004
Affiliation: University of Sussex
Contact:

Re: Using CAMB for closed FLRW model with power spectrum in

Post by Antony Lewis » February 18 2016

I think CAMB will only call the initial power spectrum function in closed models with values of k that correspond to integer n.

Brajesh Gupt
Posts: 6
Joined: January 04 2015
Affiliation: Pennsylvania State University

Using CAMB for closed FLRW model with power spectrum in sphe

Post by Brajesh Gupt » February 19 2016

Thank you, Antony! I will try that.

B

Post Reply