An edge such as you describe would require the universe to be expanding into some other space. As far as I know, we have no evidence either for or against the existence of such other space. While it may seem counterintuitive, rulers in an expanding universe will grow without the universe itself needing to expand into something that is external to the universe.

@anglophone Perhaps it's expanding into the collapse of a previous universe. I don't know. Just thinking out loud, since it's so far unknown and fun to think about.

@hankster No it is only the beginning of the local universe, the multiverse beyond it may have lasted forever. While it could be infinite in space as well, according to some thought, the edges where we see the cosmic background are caused only by, the limit of time for light to travel stopping us seeing further, our local bubble beyond which there may be alliens seeing other local bubbles out to infinity

@hankster That is also accepted by many, as are several other versions.

@Fernapple @hankster I guess it is almost a philosophical question: we have an observable universe (which appears to be finite), but how might we think about anything that is beyond the limit of observability imposed by both time and space?

@hankster Much within the universe is imaginary, cosmology has not as yet moved much beyond the hypothesis stage, about many things.