Extra relativistic components?

Matter-radiation horizon scale depends on matter density (Wmh2) and relativistic density (=1.68 rCMB for 3 light neutrinos).

Suppose rrel = X (1.68 rCMB ) so apparent Wmh = Wmh X-1/2 and Wm=1 h=0.5 works if X=8

But extra radiation affects CMB too. Maintaining peak location needs h=0.5X1/2 if Wm=1

If w=-1, 2dFGRS+CMB measure h X-1/2 = 0.71 +- 5% with HST h = 0.72 +- 11%, hence

1.68X = 1.70 +- 0.24 (3.1 +- 1.1 neutrinos)

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