For the widely accepted current value of the Hubble parameter, i.e., $H_0 \simeq 72$ $\rm {km~s^{-1}~Mpc^{-1}}$ (Freedman et al. 1998), no flat CDM model without dark energy (whose age prediction is $H_0t_{\rm {U}} = 2/3$ ) may be compatible either with the direct age estimates from globular clusters or with the indirect age estimates, as provided by SNe Ia and CMB measurements (Tonry 2002; Spergel et al. 2003, 2006).

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As an example, see the debate involving the age estimates for the radio galaxy LBDS 59W069 (Bruzual & Magris 1997; Yi et al. 2000; Nolan et al. 2001).

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... BOOMERANG)

Note that, to avoid double counting of information with SNe Ia and LSS analyses performed in the next sections, we have adopted age estimates obtained from combinations of CMB experiments only.

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