Rather good description of Hypertime…

…found, in of all places, a Doctor Who audio adventure. The Doctor (eighth incarnation – Paul McGann) has been partially possessed by a maleovent energy being called Zagreus (also Paul McGann) – two personalities, two minds, one face, one body. The emotive and slightly panicked Doctor debates with the chilling calm Zagreus:

The Doctor: The Timelords called you Anti-Time, but you are far far more than that.
Zagreus: Anti-Time, as Centrix told you, is the result of hundreds, of thousands, of living breathing beings’s futures and pasts. Was’es and Never-was’es!
The Doctor: Yes, yes, and between them they bore witness to a billion alternatives. I can see things in my mind’s eye. I can see me, thousands of me’s, doing different things in different places, but all at once. Alternative realities or maybe this is an alternative and one of those others is real. You’re part of me can’t you see what I’m seeing?
Zagreus: Always!
The Doctor: Look there! I see myself on the planet Oblivion facing a race called the Hoard. And there, look, a tiny reality where Gallifrey [the Doctor's home planet (probably)] isn’t really a planet but a timeless diamond drifitng through the stars. I can see a universe where the Timelords have terrible mind powers and another where they have ceased to exist – time wound backwards to eliminate their every trace. A planet, Earth, where the Nestines very nearly destroyed everything. And another Earth upon which I have plucked out one of my own hearts. But which is real and which are the alternatives?
Zagreus: There is no alternative.
The Doctor: You mean no one knows which reality is the real one?
Zagreus: They are all real and primary to their inhabitants. In the grand scheme of things it doesn’t matter. Who is there to care? They all exist – occasionally sharing moments and eras, the rest of the time self-contained and unaware – but all are destined to end together… and very soon.
The Doctor: I’m scared.
Zagreus: Good – you should be!

(From about 15 minutes into the first episode of Zagreus (Amazon UK) from Big Finish Productions. And really quite good.)