I have seen a couple of talks by Ajahn Brahm in which he says that just like 3-D space is curved (so that, to use an image that I think goes back to Einstein, if we had a strong enough telescope allowing us to see far enough, we would see... the back of our own head) also time si curved, so that we go round and round in samsara. Some philosophers like Nietzsche had also suggested this idea (the Eternal recurrance of the same).
However, if we take this idea seriously, it would mean that if enough time elapses, the world would come back to the same state as now, so that this very moment would repeat itself again and again (just like in space if you travel far enough you come back to the point where you started from). So my question is: how is this teaching compatible with the idea of parinibbana, according to which an arahant would cease to be after death and never be reborn? If time is circular, wouldn't this imply that the arahant will also exist again in the future if we go ahead far enough? And if so, wouldn't this mean that he/she has ceased to exist, and then somehow come into being again?
I really cannot reconcile the idea of circular time with that of arahants reaching parinibbana and 'disappearing' for ever, so I would be grateful for your help in understanding this.