Hi all,(adsbygoogle = window.adsbygoogle || []).push({});

I'm hoping someone can help me out as I'm really stuck.

With reference to the top of page 7 at http://faculty.washington.edu/mrdepies/Survey_of_Dark_Energy2.pdf

I'd like to know how to get the quoted energy density and pressure of phi from the stress-energy tensor. Im very new to tensors and the notation involved. There are times I think I understand what is going on, but then I find I can't do simple problems, like get the pressure from the stress energy tensor.

The way I'd get the energy density is by setting all indices in the stress-energy tensor to 0, but I'm not sure if that's correct?

What would help me out massivly is a step by step way to get these answers (or point me to a site that explains how to get them, I've yet to find one). Once I understand this, I suspect a lot of other stuff I've been reading about will fall into place.

Thanks in advance to anyone who can help

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# Scalar field pressure and energy density

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