I want to dicuss what large galaxy surveys
which go out to redshift z=1 or more truly measure.
I shall build my arguments, starting with the
galaxy angular position and redshift and I shall
derive the quantity to which this relates in first order
We shall see that the complications due to the fact
that we only observe on our background lightcone and
that we do not truly know the distance of the
observed galaxy, but only its redshift in not only
an additional difficulty, but especially a new
opportunity for future galaxy surveys.
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