## [astro-ph/0408547] Determination of the equation of the state of the Universe using ~ 0.1 Hz Gravitational Wave Detectors

 Authors: Ryuichi Takahashi, Takashi Nakamura Abstract: We show that ten(one) years operation of the ultimate DECIGO (DECihertz Interferometer Gravitational wave Observatory) can determine the cosmic equation of the state with such accuracy that 0.06%(3%), 0.08%(4%) and 0.06%(3%) for $\Omega_m$, $\Omega_w$ and $w$, respectively. This should be compared with the proposed SNAP satellite of 2%, 4% and 5% so that the ultimate DECIGO can give an independent determination of the cosmic equation of the state. [PDF]  [PS]  [BibTex]  [Bookmark]

Discussion related to specific recent arXiv papers
Alessandro Melchiorri
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Joined: September 24 2004
Affiliation: University of Rome
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### [astro-ph/0408547] Determination of the equation of the stat

Did you notice this paper ?
(Future) error bars of the order of 10^-4 for w_0 and 10^-3 for w_1 !

Fergus Simpson
Posts: 27
Joined: September 25 2004
Affiliation: University of Barcelona

### Determination of w with G wave detectors

Yes, it looks promising, until you realise that to produce those figures they are using the "ultimate" sensitivity of the detctor (limited only by quantum fluctuations of the 100kg test mass). They admit that in practice the sensitivity will be 3 orders of magnitude worse. In which case, I'm sure the error bars on w won't be too impressive.

Cheers,
Fergus

Alessandro Melchiorri
Posts: 128
Joined: September 24 2004
Affiliation: University of Rome
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Uhm, yes, definitly the "ultimate decigo" looks too optimistic. Will see in 30 years ! :-)