Bruce Scott TOK wrote:
Basically, although we see objects at distance we also see them in the
past and it is that which is relevant. We can see that the state of the
universe is different at high redshift than at zero redshift, and due to
the redshift distance relation this is interpreted as a difference
between past and present epoch. Note that this has a frame-independent
definition: proper time since the initial singularity. When we speak of
the age of the cosmos, we are really giving a number to this coordinate
in the Robertson-Walker metric. We can extrapolate from observations
enough to tell that there is a fundamental limit to this epoch of cosmic
time regardless of how much of the spatial extent of the universe we can
see.

I assume you're talking about things like quasars, which we see lot of
in the past and in the distance, but not so much nearby. Is it possible
that these locations are so far off, that we only see the brightest
objects from there?

Yousuf Khan