(adsbygoogle = window.adsbygoogle || []).push({}); I’ve read that most comoglocial fluids can be modelled as perfect fluids. And that most perfect fluids obey ##p=w/rho##.

I’m wondering (had a look around and can’t seem to find) two things:

i) whenever ##p=w/rho## is obeyed does this always give the 3 descriptions of the universe – 2 open universes expanding at different rates and one closed universe

ii) examples of cosmological fluids which do not obey ##p=w/rho##? And do these fluids still lead to the same 3 fates of the universe. Does any perfect fluid lead to these 3 universes?

Thanks in advance.

I'm new to this and my question is motivated by taking the single case of a couple of fluids, with different w values, which do obey the above equation of state and looking at friedmann equations and finding that it leads to the 3 desriptions of the universe. I'm now wondering how well this generalises - to finidng the same 3 universe fates.

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# 3 fates of universe holds for which cosmological fluids?

**Physics Forums | Science Articles, Homework Help, Discussion**