IT'S entirely possible that there are happy, well-adjusted people who never traffic in regret or ponder what their lives would be like if they'd accepted a certain job offer years ago, had married A instead of B or had planned their financial futures differently. If they exist, these living-inthe-moment individuals are not to be found in the Palo Alto of "Come With Me," Helen Schulman's strikingly original, compelling and beautifully written sixth novel. In this Palo Alto, you'll find people who not only wonder about the other paths they might be following, but have access to technology that helps them explore those alternative lives. This is, don't forget, Silicon Valley. Using algorithms and the accouterments of virtual reality (headphones and special glasses, for starters), one resident entrepreneur has crafted a way to "visit" the life that might have been. "Math can tell you what would happen if you altered history?" he's asked. His reply: "Math plus info, sure. At least a fairly good approximation." ("Info" refers here to the indelible fingerprints left by social media posts and internet searches.) Welcome to your multiverse. This perhaps suggests that Schulman has left behind the hyper-realism of her two most recent novels for the realms of speculative fiction. Fortunately, that's true only in a small way. Multiverse theory functions primarily as a thematic framework here, and the headphones and glasses make only a few appearances. In "Come With Me," Schulman's central preoccupations continue to be the endless complexities of marriage, midlife and family and the ever-pressing need for people, even in Silicon Valley, to connect. Her writing in this new novel has the humor and wit, the careful eye for social detail and astute character development, that made her previous novel, 2011's "This Beautiful Life," a best seller. Amy and Dan have been married for 20plus years. They have three sons - Jack, a love-struck teenager, and 8-year-old twins, Miles and Theo, fondly and hilariously referred to as Thing One and Thing Two, or The Things. Dan is an idealistic print journalist, which is to say he's unemployed and lacking viable options for re-entering the work force. Amy has abandoned her hopes for a benefits-stuffed job at Google and is supporting the family doing P.R. for Invisible E-nk, a start-up founded by Donny, her best friend's 21-year-old son. Donny is a genius, a Mark Zuckerberg wannabe who's seen "The Social Network" ("a generational call to arms") at least a dozen times. He has the audacity of a first-world dictator and an aversion to deodorant, and he's one of several vivid secondary characters who steal scenes from the sympathetic but less colorful leads. Amy describes her lush neighborhood as a "ludicrously perfect patch" of the world. Naturally, there's trouble in paradise. Amy and Dan's marriage is sliding into passionless discontent. Sex is infrequent and money is scarce. Dan has started flirting with a brilliant photojournalist, and Amy has obsessively taken up running, in order to "pretend she was unencumbered again." For her, this isn't exercise so much as a cherished "vacation from her life." The novel covers three nonconsecutive days during which Amy will be persuaded to test out Donny's potentially lucrative algorithms and venture into her multiverse. There she will glimpse lost loves and - she hopes - the fate of the daughter she might have had if she hadn't terminated her first pregnancy. Dan will fly off to Fukushima, Japan, to pursue a possible story but mostly to pursue Maryam, a beautiful, hyper-talkative transgender woman with a multinational background. (Maryam is a fascinating character, but the ease with which she walks through the world and the near shrug with which Dan accepts her gender seem more like the ideal than the real.) Back at home, a decision made by teenage Jack's best friend will create a crisis that exposes betrayals and threatens to unravel the fragile threads that have been holding the family together. Schulman's work has often had elements of reportage, from the precisely noted details of 9/11 in "A Day at the Beach" to the sexting scandal at the heart of "This Beautiful Life." Despite its speculative elements, "Come With Me" continues in this vein. In an author's note, Schulman cites as the starting points for the novel her interest in and extensive research into the tragic events at Fukushima, the perils and possibilities of the internet and the mystery of teenage suicide clusters in Palo Alto. The section of the novel devoted to Fukushima is unsettling in its immediacy. It's also strangely beautiful even if, at moments, the author's research feels blended in a bit insistently: "Fukushima City was never evacuated," Maryam announces. "It's the capital of the prefecture. Evacuation orders started small in an expanding radius surrounding the nuclear power station. Some residents of this city didn't even know about the nuclear accident until 10 or 11 days later." And so on. Discussions of multiverse theory are nearly as thorough. Even so, Schulman weaves all this material - along with multiple points of view - into a tight, urgent narrative that builds in tension until, about a hundred pages in, I found it difficult to put the book down. The disparate sections of the novel create a collective, coherent portrait of a world that's catastrophically out of balance, despite the comforts and privileges of certain corners. Radiation is leaking into the soil and ocean at Fukushima, and radioactive waste is deposited in trash bags left beside the road. In the buffered world of Silicon Valley, teenagers with keys to the future in their hands are following one another in copycat acts of self-destruction. The most loving and intimate relationships are perhaps ones like Jack's with his girlfriend, Lily, which is conducted mostly in virtual fashion. Amy and Dan's family sits down to eat organic vegetables from the farmer's market with a place set for Lily, who will be Skyped in from Texas on Jack's laptop. Even virtual sex, from Jack's perspective, can be "better" than the real thing. "What was so amazing about Lily was when they did this, when they had phone sex, she just obeyed him. In real life, she sometimes talked." In the end, all the travel in the novel - both real and virtual - leads back to the relatively conventional question of whether or not Amy and Dan can stay together after engaging in their different styles of straying. Amy arrives at her answer with the help of Donny, the least socially adept character we meet. Perhaps "math plus info" can be put to some good use after all. The final pages of the novel don't tie up all the loose ends and don't offer promises of happily-ever-after for anyone. Instead, Schulman delivers an ending that's ambiguous but hopeful about human connections, tender without being sentimental about fated love. That's about as much as these characters can expect in their out-ofbalance world and probably as much as we readers can expect in ours. One of the many triumphs of "Come With Me" is that Helen Schulman makes it enough. Stephen McCauley'S seventh novel, "My ExLife," was published last spring.