From Wikipedia, Observable Universe page https://en.wikipedia.org/wiki/Observable_universe
Some parts of the Universe are too far away for the light emitted since the Big Bang to have had enough time to reach Earth, so these portions of the Universe lie outside the observable universe.
I have problems in understanding this sentence. (Assume by observable we mean observable by photon detection - which the reference to "light emitted" in the above source seems to imply too). As from my current understanding of the Big Bang cosmological model, the farthest we can see is up to the last scattering surface of the epoch of recombination. This we observe today as the cosmic microwave background (CMB) - and thus we can indeed "see" it. Mustn't all other parts be less far away than that surface of last scattering? So how can there be other parts we aren't (in principle) able to see?
I think i realize my error of thought. I thought that, given that the epoch of recombination occured relatively early in the age of the univers, i.e. around only after 380 kyears after BB, the space beyond the SoLS would be tiny in comparison to the space before. What i didn't realize is that as is currently assumed in inflationary models, space had already risen to enormous dimensions before this epoch and has been considerably expanding since. Which means, the inside volume of our local SoLS might only span a tiny volume of all of the entire universe.