CAMB: Initial condition phidot

Use of Healpix, camb, CLASS, cosmomc, compilers, etc.
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Christine Fix
Posts: 2
Joined: December 20 2005
Affiliation: University of Ulm

CAMB: Initial condition phidot

Post by Christine Fix » December 20 2005

Hi,

I'm trying to run CAMB with the Quintessence module but with a constant phidot unequal to zero.and I'm a total greenhorn when it comes to programming in Fortran90. The potential I want to use ist [tex]V(\phi) = V0 / (d * sinh(B * \phi) + cosh(B * \phi) - 1)^2[/tex]. It runs wonderfully with phidot=0, that's not the model I want.

Can someone help me with that fast?

Thanks,

Christine

Antony Lewis
Posts: 1413
Joined: September 23 2004
Affiliation: University of Sussex
Contact:

Re: CAMB: Initial condition phidot

Post by Antony Lewis » December 20 2005

You can change the initial conditions in the code - search for phidot in the source.

Incidentally, the non-public quintessence module currently doesn't describe the normalization of V accurately: the output of the Vofphi routine should be in 1/Mpc^2 units. In other words if V is 10^{-122} in natural units, Vofphi should be returning
[tex]
10^{-122}(Mpc/c)^2 /T_{pl}^2 .
[/tex]

Christine Fix
Posts: 2
Joined: December 20 2005
Affiliation: University of Ulm

CAMB: Initial condition phidot

Post by Christine Fix » December 21 2005

Hi!

Sorry for this stupid question, but what is [tex] T^2_{pl}[/tex]??

Christine

(A bit desperate due to presure of time;-)

Antony Lewis
Posts: 1413
Joined: September 23 2004
Affiliation: University of Sussex
Contact:

Re: CAMB: Initial condition phidot

Post by Antony Lewis » December 21 2005

Planck time squared.

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