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Dichronauts

gregegan.net

100 pointssohkamyung29 comments

I recently read Greg Egan's previous trilogy set in an alternate-physics universe, the Orthogonal trilogy, and it was excellent. (In Orthogonal, time is a space-like dimension, and relativity, optics, and chemistry change accordingly.)

Not only does Egan invent weird universes and let the reader follow the math involved to whatever extent they want, he also tells great stories in the universes he invents.

Orthogonal tells of a society's quest through deep space, searching for a way to survive and save their home planet, using technology they have to invent along the way. (The characters can speak in diagrams, with which they explain the science to each other and to the reader.) It builds up to include some plot twists that are only made possible by the strange nature of time and space.

Dichronauts seems to be an iteration on this formula (now there are two time-like dimensions), which sounds more bewildering and constraining to the plot, but I trust Egan to do it well.

Exciting! Egan is one of my favorite authors; he has an incredible imagination, and is one of few sci-fi authors who often puts an extensive list of citations in at the end of his books. No doubt the physics in this book are very carefully thought out. Looks like there are descriptions of the alternative spacetime he's using at the bottom of the page, so I'll have to give those a read!

Neat. I noticed that the summary for this popped up on Egan's site a few months back, but there wasn't nearly enough detail for me to wrap my head around the premise. Gonna take another look at it now.

For anyone who finds this interesting, you might want to check out Christopher Priest's Inverted World, which is based on a vaguely similar premise. (Although much more closely tied to the "real world", and not nearly as mathematically rigorous.)

Just posting a follow-up comment to say that the interactive simulation is really the highlight of this set of pages. I was expecting a trivial demo widget, along the lines of the animated GIFs in the article, but it's actually a full 3D rigid-body simulation.

Playing around with blocks and ramps in a browser does a great job of taking the mathematical analysis given in the article, and making it at least somewhat intuitively understandable. But on the other hand, it doesn't exactly make a convincing case that a world built according to these rules could ever be stable!

http://gregegan.customer.netspace.net.au/DICHRONAUTS/02/Inte...

I've just come here to say that I came here after literally finishing _Permutation City_ around two hours back. It was great.

I can't wait to try Schild's Ladder -- differential geometry, yay!

Is it 'Into Darkness' that has the idea of a space where you can only move forwards, not sideways? This sounds like that mixed with the rigorous alternative physics of the Clockwork Rocket series.

That is, it sounds fun, for quite difficult values of fun.

I've always been really disappointed in Egan's work. He's been praised to the stars, so my expectations were kind of high. But when I actually read his work, I found it to be pretty shallow and dry, with cardboard characters, like much hard scifi. He kind of reminds me of Vernor Vinge, for whom I'd also had high hopes, as both authors deal with the singularity a lot -- an idea I really find compelling. Unfortunately, I find their execution to be pretty weak, and even their ideas are mediocre.

Do you have, in mind, superior works that deal with similar concepts? I'm looking for new reading material & would appreciate more author/book recommendations.

Well, they don't exactly deal with the same concepts, but my favorite scifi authors are: Philip K Dick, Frank Herbert, and Stanislaw Lem.

> with cardboard characters, like much hard scifi

I think a lot of sci-fi fans (myself included) don't pay much attention to that because, well, it's not why we read sci-fi. People are boring. Cool science and weird technologies and interplanetary-scale politics are fun. For every story you'd like to tell to make a character "deep", there's a whole genre dealing with it in real-world settings already. Troubled teenagers? Sure, there's a section on Amazon just for that. People in love? Every other book is about this. Etc.

Just my 2¢.

Well said.

I dunno, man. SF exists as a lens to say something about people. The whiz-bang technology is...I want to say "wank", but I don't mean it pejoratively. That stuff just doesn't mean much. I have great admiration for folks like Robert Forward as people, but...once you take away the technology, they're not saying much. It's potboiler stuff. And that's fine, but I look at that, and then I look at somebody like Spider Robinson, whose inclusion in Analog got Ben Bova no end of shitty emails, and...he's actually sayin' stuff. Like, you don't have to agree with it, but there's something, once you put the book down, that you can take away.

I don't care how hard your SF is: it is always and without exception about what technology does to people--otherwise it's an engineering manual for something that doesn't exist. A lot of the "greats" of hard SF never got that. (Forward, again, comes to mind.) I have a more charitable opinion of Egan than the OP does, to be sure, but I have a strong reaction to the notion that the human element of this should ever, ever be played down. Everything, ultimately, is about people. We miss that at our peril.

This is why most of Heinlein (the tail end of his career notwithstanding--we all know it gets weird, let it lie) still holds up so well despite so much of technology and society having changed in the interim. Even books that weren't trying to be hard SF (his juveniles, which IMO are some of his weakest books, tended towards this) had engineering and mathematical verisimilitude, but it was a concern set well behind the characters who had stuff to do and learn and grow through. (Most of the time. Lookin' at you, Red Planet.)

> The whiz-bang technology is wank

Egan is good because nothing in his books is "whiz-bang". He's not writing about turboencabulators or laser guns; he's writing about worlds in which nature itself is fundamentally different, and in a much more fulfilling way than you would find in a fantasy book (because you know Egan's worlds are at least as mathematically viable as our own).

I disagree that SF exists to say something about people. Authors like Egan use it to say something about the universe itself, which is a much more vast and beautiful topic than the everyday goings-on of humans. Perhaps your focus is too anthropocentric to enjoy it.

> I dunno, man. SF exists as a lens to say something about people...otherwise it's an engineering manual for something that doesn't exist.

I don't think you're appreciating how much other people's tastes differ from yours. I love to read an engineering manual for something that doesn't exist. That is exactly why I read Greg Egan books. The plot is a motivation to get me to think about physics, not vice versa.

As I said, some readers don't care that much about "people stuff". Personally I do, but I also independently care about the sci/tech stuff, and "an engineering manual for something that doesn't exist" sounds really exciting to me. Hell, I spent better part of my youth writing such manuals for technology of Star Trek and some other sci-fi universes.

For example, I've been reading Weber's "Safehold" series recently. Sure, characters are interesting. But I'm as much - if not more - interested in how the characters solve problems within the constraints of the environment they live in. I love to read about politics, I love to learn about naval and ground warfare strategy, about how development of technology transforms the society (not individuals).

I believe both kinds of preferences deserve to be satisfied. But the "people stuff" is done by 99% of the books out there. So I don't see lack of character-focus as a valid criticism of the remaining 1%.

> I dunno, man. SF exists as a lens to say something about people.

That sounds incredibly boring to me. Count me as one sci-fi fan who doesn't think about it that way at all.

In some sense, science fiction isn't really a genre. It's really more the lifting of certain restrictions that are in the other genres. You want alternate rules of physics, which is how Greg Egan rolls? Well, you're pretty much automatically in science fiction... even if the story you subsequently tell within those alternate rules of physics are an otherwise normal romance, or adventure, or whatever.

So whereas a when you read a western, you basically know everything about all the basics of the world, from the basic laws of physics through having a pretty decent idea of why "the Claytons would like to burn down the town" (despite having just those nine words, a genre-savvy Western reader has already got three or four basic plots in mind), and thus those things do not need to be explained, in science fiction you need at least some explanation of how the world is different.

Jamming that into a story pretty much has to come from somewhere else. Even in non-science fiction, seeing a novel perfectly balance Character, Plot, and Dialogue, to say nothing of the other elements of a story, is extremely unusual. I mean, like, award-winning unusual. Throw in the requirement that you have World Building in there and you'll generally have to pay the penalty somewhere else. It's just part of reading science fiction.

I can not recall if I first saw this argument from Niven or Asimov (or, worst case, one of the other classic writers); anyone who does please reference if you'd like. Unfortunately, my science fiction bookshelf is all meatspace and the indexing is terrible.

Honestly, that just sounds like an excuse for bad writing. There are science fiction authors who can do a good job at maintaining this balance. For me, Greg Egan just hasn't been one of them.

Yes, there are science fiction authors who do good characters. Lots of them, even.

However, I would ask you to consider how many of those stories take place in a literally different shape of space-time.

Not just lip service to vaguely handwaved "strange space-times" in the style of Lovecraft, either, but extensively realized alternate geometries that drive the story.

There's a reason you don't get all of these things at once. At least, I can't think of a story that hits all these points at once.

Btw, I'm not expecting you to change your mind about Egan's work. Even by the standards of science fiction, I'd consider him a niche taste. If he's not to yours, party on and enjoy what you want to. I'm just trying to explain his work.

Axiomatic is probably the best collection of Egan's short stories if you're interested in people.

> and even their ideas are mediocre

I don't recognise Greg Egan's work from this description.

It's true Egan's characters are extremely dry with weak character development but that's the beside the point. The plot and the characters are just a facade on the exploration of new physics.

You might like Neal Stephenson's novels. They deal with very interesting concepts but also have great plots and character development.

I tried reading Snow Crash and found it to be childish.

Compared the rest of his work, it is childish.

Cryptonomicon, Anathem, and The Baroque Cycle are anything but.

I agree it was, but his other stuff is a lot better. Diamond Age is a favorite of mine.

For Vinge, I recommend Marooned in Real Time. To me, that is his best novel.

I read Marooned in Real Time, and was disappointed, as with everything else I've read by him. By now, I think I've given both Vinge and Egan enough of a chance.

I'll check out Diamond Age, however, as I'm a fan of nanotech and am interested in how far scifi can push it.

Ha don't bother, you won't like it either.

Snow Crash is a loving parody of the cyberpunk genre. Everything is way over the top. Every trope is turned up to 11. When you look at it that way, you'll see why it comes across as childish (and in many ways, it is).

If you like tales of the singularity and you haven't read it yet, try Charles Stross's Accelerando. It's a hell of a yarn and has no lack of character.

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