October the First Is Too Late is a science fiction novel by astrophysicist Fred Hoyle. It was first published in 1966 says wiki, laconically. There is more to be said but you'll enjoy the book more without this review, so read it first. I guess that's a recommendation. But don't let me get too carried away: whilst it is written by yer Notable Physicist and while it is based on a quasi-respectable idea it is tosh.The plot: our hero, a composer - and making the hero a composer is cute, and lends nice colour to the book - goes on holiday with a scientist, and mysteriously the scientist goes missing for a bit, before reappearing. Life goes on. Then it is discovered that - somehow, inexplicably, obvs - the sun is acting as a giant transmitter, beaming vast streams of information off somewhere. I don't think anyone ever bothers to try to work out exactly where it is being sent, because as it turns out that doesn't matter, which obviously the characters know in advance. Then, while they're in Hawaii, the world mysteriously fractures into multiple zones, each corresponding to a different time: Hawaii in the "present" of the book's narrative, England the same except a few months off, Europe back in WWI, Greece at the time of Sophocles, Russia in the unimaginably far future where the Earth has been through scouring by an enlarged sun and is now a flat glass plain. The characters talk about the "solar transmitter" and realise the bandwith is what you'd need to xferring the full state-of-the-Earth, and deduce that errm this somehow relates to the splitting. Out hero goes off to visit antient Greece, cue various hilarities, gets into a music competition and is whisked off to another bit - Mexico - where the folks from 6 kyr ahead have ended up. Where his scientist friend mysteriously turns up. Cue much discussion - about the moving spotlight theory of time and so on - but since none of it made any sense I paid little attention. The end.
The book doesn't even pretend to trouble itself about who might be making the Sun do this stuff, or who my have fractured the Earth, or why; so inevitably as the book ends with none of that explored let alone explained, a sense of disappoinment ensues. The people 6 kyr ahead have, as usual, a mixture of super powers and comedy levels of tech already superseded by mobile phones; such is the fate of all such. Hoyle attempts some naive and rather dreadful politics: after about our time the world goes through cyces of expansion, collapse, the same expansion and so on; until eventually folk realise that having lots of population is really awful - think of all those dreadful plebs, watching those ghastly football matches, my dear it just doesn't bear thinking about - and the world would be better with - let's pluck a random number out of the air - 5 million people. The idea that people, thining, might actually be valuable never occurs to him, because naturally he, being a valuable and indeed notable astronomer, is going to be one of the saved. See-also Derek Parfit's Repugnant Conclusion.
Trivia: I mentioned the scientist-going-missing bit, and indeed this occupies a fair slice of the intro. It turns out that he comes back - ta da! - without a birthmark he formerly had. Towards the end, when it gets all science-y, we are told that he came back as a copy, but an imperfect copy. But... why would the vague impersonal copying process choose to make such a mistake? Why not turn him blue, or come back without a spleen, or any of a million other possibilities? If it wanted to send a signal, why not tattoo him with a message? And why did this one guy get a copy / exchange, months before the real action of the rest of the book kicks off? It makes no sense at all, unless our Fred hadn't plotted it all out in advance, had this one bit written, and decided not to remove it at the end even though it had become irrelevant.
