I am trying to modify the equation file for quintessence for CAMB provided at https://camb.info/equations_quint.f90.

In

**subroutine EvolveBackground**, the energy density of the scalar field is defined as

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`tmp=a2*(0.5d0*phidot**2 + a2*Vofphi(phi,0))`

*prime*denotes the derivative with respect to the conformal time.

But later in the file in

**function Quint_GetOmegaFromInitial**, it is given that

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`Quint_GetOmegaFromInitial=(0.5d0*y(2)**2 + Vofphi(y(1),0))/(3*adot**2)`

But considering the definition

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`y(2)=phidot*astart**2`

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`tmp=a2*(0.5d0*phidot**2 + a2*Vofphi(phi,0))`

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`(0.5d0*y(2)**2 + Vofphi(y(1),0))`

I am not sure if it is an error in the code, or if I am missing something.

Best

Joseph