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Review of Probability Moon by

Probability Moon

by Nancy Kress

This is exactly what I needed after the disappointing Clan of the Cave Bear. Nancy Kress is an author whose ability to make me think never fails, even if I don't always enjoy her characterization. She doesn't just touch on or grapple with Big Ideas; she stalks them, lassos them, and puts them to work doing her bidding. And she is really, really smart. Wikipedia doesn't tell me what she specialized in during her formal education, so I'm not sure how much of the knowledge that shines through her stories comes from that and how much is the result of careful research. In any event, Nancy Kress is a truly amazing author. I've read several of her novels, but they have all been set in the near future. Probability Moon, on the other hand, is hard science fiction set in a universe where humanity has begun colonizing the stars. I couldn't wait to see Kress' take on this.

This book has great back cover copy. I read it aloud in a dramatic voice twice, and it rocks. It could be the opening narration for a video game cutscene. To summarize the summary: humans get around using space tunnel technology left behind by a long-gone species. They're in a war with another species, the Fallers. They've discovered a planet whose inhabitants experience "shared reality". More importantly for the human military, one of the moons orbiting that planet is an ancient weapon built by the same species who built the space tunnels. It's Nancy Kress, and it's hard science fiction. So it's going to be awesome, right?

In hindsight, I confess my expectations for this book were probably too high. As the first in a trilogy, it concludes one of its plots but leaves the larger mystery behind Orbital Object #7 unresolved. When I finished, I felt like I could have begun Probability Sun immediately, and I was sorely tempted to do so. I have avoided that temptation, partly because I don't yet have a copy of Probability Space. But these books are short and the action and dialogue makes them snappy reads; I could easily devour this trilogy in a weekend.

As has been typical in my experience with Kress, we differ when it comes to characterization. I found the villain in Beggars in Spain to be rather disappointing. Occasionally, Kress' characters approach a level of caricature that does not reflect well upon the story. The same thing happens here with David Allen, graduate student in xenoanthropology who accompanies the expedition to World and slowly succumbs to delusions of grandeur and megalomania.

Antagonists who are mad are much less interesting, in my opinion, than run-of-the-mill garden variety sane antagonists. There is something of a loss of volition that accompanies madness, or at least a loss of judgement, that makes these characters less threatening in an ideological sense. In that respect, someone like Jennifer Sharifi from the Beggars trilogy is a superior antagonist to someone like David Allen—she might have seemed cold and inhuman, but she was rational and all of her faculties were functioning. That made her much scarier. If the choice is between a villain who is aware of what he or she is doing but utterly believes in his or her position and a villain whose actions are the result of a medical condition, the former is always going to be more imposing. I couldn't take David Allen very seriously, and I found the parts of the book where the narrator visits upon his perspective more annoying than anything else.

I am relieved and happy to report that this is the only major flaw with Probability Moon. Although the other two plots do not quite approach the levels of epic awesomeness required to make my head explode, they still combine to create a decent science-fiction novel.

On World, everyone experiences "shared reality". This is a very interesting and, at least at first, poorly-explained concept. Basically, Worlder who does not "share reality" will experience headaches of increasing intensity. "Sharing reality", as far as I interpret Kress' explanation, means sharing the way other people look at the world. We don't actually get that many concrete examples aside from how people who do share reality regard those people who don't—the unreal, as they are called, who are ignored or driven out until the government department of Reality and Atonement declares them real once again. One of the central issues in Probability Moon surrounds the ambiguous status of the Terran expedition: are they real or unreal? Until Reality and Atonement makes that call, they live in a limbo where other Worlders deal with them, but always somewhat uncomfortably. The Terrans take steps to ensure they give the appearance of sharing reality, but of course it's difficult. One of their goals is to uncover the source of shared reality—is it a pathogen, is it genetic, is it a neurological feature? In the end, as one might expect, it turns out to be related to the mechanism of Orbital Object #7.

The weapon orbiting World and military physicist Syree Johnson's attempts to understand it are the most interesting parts of Probability Moon for me. Don't get me wrong: the combination of both plots are what make this book so interesting and, ultimately, successful. Probability Moon is, to use a term I hate using even though I've used it several times in this review, "hard" science fiction in the way Kress treats space travel and technology in general. Yet it is also "social" science fiction. It is a blending that testifies to Kress' talents as a writer and belies the very possibility of meaningful distinctions like "hard" and "soft" or "social" science fiction. Probability Moon is just science fiction, really good science fiction.

Still, I will own up to favouring the investigation of Orbital Object #7 over what's happening on World. I'm a technophile, OK? I can't help it. I love technobabble, and to Kress' credit, she is either familiar enough with these concepts or has done an impressive amount of research to make her technobabble sound plausible to people who are actually familiar with these areas. For example, here's how she describes Orbital Object #7:

The artifact emitted no radiation of any kind, had no magnetic field, and no thermal gradations. The hull, 0.9765 centimeters thick, was made mostly of an allotropic form of carbon that resembled a known class of fullerenes but was subtly different. The artifact contained no heavy metals, nothing with atomic number above seventy-five. It massed slightly less than a million tons. Inside was mostly hollow, although unidentifiable structures were suspended inside (how?) in an extremely complex but partial manner, without direct connection to each other. These unknown but stable structures appeared to be without any mass—an impossibility. When the computer ran mathematical analyses, the suspensions suggested a complicated web wherein each curve folded back on itself many times, a sort of multidimensional fractal. Computer breakdown further suggested a strange attractor, a region in which all sufficiently close trajectories were attracted in the limit, but in which arbitrarily close points over time became exponentially separated. Syree figured the Hausdorff dimension of the suggested fractal. It was 1.2, the same dimension as the galactic filling of the universe.

I admit I have no idea how to build a space tunnel myself, and I'm not quite sure what Kress means when she says "galactic filling of the universe" (quantum foam, maybe?). Regardless, it tickled me to see her talk about fractals and Hausdorff dimension. I was reading this while having lunch with my friend Aaron, who is actually studying such areas of mathematics for his masters degree. So I immediately distracted him from the Dresden Files book I had lent him to make him read that paragraph. This is, as far as I can recall, the first time I have seen the Hausdorff dimension mentioned in a science-fiction book. Go Kress! Later references to concepts like Swarzschild radii, while less exotic, were still quite welcome.

Syree Johnson is also probably the most interesting character, such as she is. Kress gives us quite a bit of her backstory, explaining how she comes from a long line of strict military families and thus excuses herself nothing when it comes to weakness. Nevertheless, Syree is obviously not just a military officer but a genuinely curious scientist who wants to understand how Orbital Object #7 works. She is torn between that curiosity and her duty to destroy the object before it can fall into Faller hands. And she's also the face, for us, of the human military.

In Probability Moon, humans sort of drop out of the sky (TVTropes alert) to visit the World. They are mindful of possible contamination but still rather blasé about the entire business. Worse still, it's all just a cover so that the human military can steal one of the planet's moons. Sure, the moon happens to be an ancient superweapon. But still. It's a moon. It's kind of important, not to mention nominally the World's. We don't see any sort of arguments related to cultural imperialism or the fact that taking Orbital Object #7 without even asking is nothing short of theft. Nevertheless, I think it's implied in the way Kress frames the entire situation: at least, to me, it was clear that we humans were waltzing into the system, taking what we wanted, and leaving little if anything of value behind. It could happen. (TVTropes)

Probability Moon has its fair share of action and tension; as far as drama and pacing goes, this book is pretty good. As is common for trilogies, it leaves me wishing I had learned more about the war with the Fallers—in particular, I'm curious to learn about the political fallout from what happens regarding Orbital Object #7. The book ends rather abruptly, not so much with a cliffhanger but with a definite sense that the story is far from over. This is definitely not something I would read if I were looking for a standalone novel, although your mileage may vary. I enjoyed this new facet to Nancy Kress' writing; I liked reading a story by her that involves space ships and relativistic weapons and quantum phenomena. It makes me look forward to the rest of the trilogy, which I'm sure will have more answers. Probability Moon did not, unfortunately, quite manage to make my head explode—but as with anything Kress writes, it still took me hostage.


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