Please show me how to solve this paradox(adsbygoogle = window.adsbygoogle || []).push({});

cos the Friedmann equation is:

[tex]

H^{2}= \frac{8*pi*G*rho}{3}-\frac{k*c^{2}}{R^{2}}

[/tex]

but the concordance model says that k=0, so we can eliminate the last term of the equation

then we isolate rho, the density of energy:

[tex]

rho=\frac{3*H^{2}}{8*pi*G}

[/tex]

but however, the formula for the critical energy density is

[tex]

rho_{crit}=\frac{3*H^2*c^2}{8*pi*G}

[/tex]

but the concordance model says that rho=rho_{crit}

but you see that the 2 formulae are not equal, there's an extra c^{2}in the formula for rho_{crit}

I can't figure where is the mistake

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# Friedmann paradox

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