Does CAMB include the parameterisation (w0, wa) for the dark energy equation of state?

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Does CAMB include the parameterisation (w0, wa) for the dark
Hi Everyone,
Does CAMB include the parameterisation (w0, wa) for the dark energy equation of state? It looks like the general code assumes w0 is a constant. There is a new 'quintessence' patch, but I can't figure out if this works for the (w0, wa) parameterisation (the link to the notes is broken).
Thanks, Anais.
Does CAMB include the parameterisation (w0, wa) for the dark energy equation of state? It looks like the general code assumes w0 is a constant. There is a new 'quintessence' patch, but I can't figure out if this works for the (w0, wa) parameterisation (the link to the notes is broken).
Thanks, Anais.
Re: Does CAMB include the parameterisation (w0, wa) for the
Hi Anais!
You can add the parametrization just by changing the equations.f90 file properly (do not forget to change the equations for the dark energy perturbations as well, since now the time derivative of w is not zero) and by adding the extra parameter wa in the params.ini file. You should also change the inidriver.f90 file, of course...
Let me know if that works!
Olga
You can add the parametrization just by changing the equations.f90 file properly (do not forget to change the equations for the dark energy perturbations as well, since now the time derivative of w is not zero) and by adding the extra parameter wa in the params.ini file. You should also change the inidriver.f90 file, of course...
Let me know if that works!
Olga

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Re: Does CAMB include the parameterisation (w0, wa) for the
The notes are at
http://cosmologist.info/notes/CAMB.pdf
Of course if adding w_a you either need to restrict to models where w doesn't cross 1, or ignore problems that occur when it does.
http://cosmologist.info/notes/CAMB.pdf
Of course if adding w_a you either need to restrict to models where w doesn't cross 1, or ignore problems that occur when it does.

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Re: Does CAMB include the parameterisation (w0, wa) for the
Thanks Olga and Antony. I'll have a look at this.

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Does CAMB include the parameterisation (w0, wa) for the dark
Also, you can have a look at the Mathematica Interface for CAMB, which allows for any 2 parameter w(z) equation of state, and can be found at (binaries, demo videos of the interface and documentation):
http://nesseris.physics.uoi.gr/
Cheers,
Savvas
http://nesseris.physics.uoi.gr/
Cheers,
Savvas