Where ’ s the matter ?
The answer seems to be : “ distributed according to a power spectrum with at least one feature ( local maximum ) near 120–130 h ^ { -1 } Mpc ” .
Analyses of the Iovino , Clowes & Shaver quasar candidate catalogue at z \sim 2 and the 2dF Quasar Survey 10K Release ( 2QZ-10K ) support this claim , which has previously been made both for low redshift survey analyses and for high ( z \sim 3 ) redshift surveys will be presented .
This feature ( i ) offers a comoving standard ruler which can lift the matter density–cosmological constant ( \Omega _ { \mbox { \small m } } – \Omega _ { \Lambda } ) degeneracy and ( ii ) might be due either to baryonic acoustic oscillations or to Planck epoch physics which survives through inflation .
( i ) The 95 % confidence constraint from the 2QZ-10K is \Omega _ { \mbox { \small m } } = 0.25 \pm 0.15 , \Omega _ { \Lambda } = 0.60 { \pm 0.35 } .
This constraint is independent of cosmic microwave background constraints and type Ia supernovae constraints .
The only assumptions required are ( a ) that the Universe satisfies a perturbed Friedmann-Lemaître-Robertson-Walker model with a possibly non-zero cosmological constant , ( b ) that the density perturbations in this model on large scales ( \gg 10 h ^ { -1 } Mpc ) remain small ( “ linear ” ) and approximately spatially fixed in comoving coordinates , ( c ) that the statistics ( power spectrum or correlation function ) of the perturbations are redshift independent , and ( d ) that quasar redshifts are cosmological .