THE BROOM OF THE SYSTEM By David Foster Wallace Viking/Penguin. 467 pp. $18.95. Paperback, $7.95

THIS IS a hot book; this is a terrific novel. The publishers are talking Pynchon, and there are definite similarities. The names for one thing: Biff Diggerence, Mindy Metalman, Sigurd Foamwhistle, Judith Prietht. The ramshackle, exfoliating, synchronistic plot reminds one of Pynchon, too, as does the book's fractal tales-within-tales formal structure, as does the author's passionate concern with his characters' lives. But The Broom of the System is assuredly not by Thomas Pynchon; it is by 24-year-old David Foster Wallace, a 1985 graduate of Amherst College.

As a good novelist must, Wallace has an eidetic memory for dialogue. When his characters rap on in their flat-tire Valspeak, we realize that we've heard talk like this for a few years now, even though we've never seen it written down this well. " 'No, I mean I could not believe it. When he said it to me, I just totally freaked out. I totally freaked. I was like:' the girl gestured." How great| Girls are always saying, "I was like:" and then gesturing or making a noise, and Wallace has found a way to write it down. I was like:

" . . . "

" . . . " is another of Wallace's linguistic creations. It's something his characters say instead of mumbling. " . . . " They say it a lot. It's good and it works, though often -- and here we touch on a weak point -- it feels like too much trouble for the reader to trace back through a half-page of unattributed phrases and " . . . "s to figure out who's supposed to be talking. Padding is padding, even when it demonstrates a point. Even so, most of Wallace's book is a fast, pleasant read. By the way, one more nice trope he coins is "Fnoof." That's what his characters say when they're sleeping. "Fnoof fnoof."

The book's main character is Lenore Beadsman. In the first chapter we see her as a teenager in 1981, witnessing an Animal House-style courting scene between two Amherst boys and her Mt. Holyoke sister's roomies. The rest of the book is set in 1990. Lenore is embroiled in a relationship with an older man named Rick Vigorous, who has a really really tiny penis and who has unbelievably foul dreams. "Kind of hard to take a man seriously who wants a spanking for Christmas," as Lenore's friend Candy Mandible says about Rick. He wears a beret to cover his bald spot. Rick represents, I would hazard, the aspect of Wallace's personality that got him to start this book. We often hear Rick talking, and we get to read or hear, verbatim, a number of stories that Rick has made up. They're good stories, in a sick way, but by the end of the book we're as tired of Rick Vigorous as Lenore is: "I think new heights of spasmodic weirdness are being reached."

Early in the book, Lenore's great-grandmother disappears from her rest home. As Lenore searches for her, she bounces into and off of most of the people who have mattered in her life. The book's first Animal House scene takes on deeper and deeper resonances. At the climax, Lenore seems to attain what she's been blindly struggling towards for some nine years: self-determination and adult love. Lenore and her eventual true love might be thought of as representing the aspect of Wallace's personality that got him to finish this book, or rather, the aspect of Wallace's personality which finishing this book has helped him express.

It's a cathartic experience, with a lot of laughs, and a lot of deeper meanings. The missing great-grandmother (who may have absented herself precisely to force Lenore's maturation) was a student of Wittgenstein at Cambridge, which fact ties into a really heavy-duty network of images about language and communication. Lenore works as a switchboard operator. The tunnel for the phonelines is overheating and messages are getting switched. Lenore has a pet bird that learns how to talk. Rick seeks out his initials, carved years earlier in an Amherst toilet-stall. People talk and talk and we have to guess who's talking. The walk-on psychiatrist, Dr. Jay, is obsessed with the distinction between inside and outside and with the way that sex and language can penetrate the "membrane."

The book's title comes out of the communciations network as well. It's from a Wittgensteinian example that asks which part of a broom is more fundamental. Two equally good answers are: the bristles if you use it to sweep; or, the handle if you use it to break windows. "Meaning as fundamentalness. Fundamentalness as use. Meaning as use." Like a real object, The Broom of the System is rich enough to suggest many uses: avant-garde lit, vulgar comedy, Bildungsroman, romance.

One of the loveliest romantic passages of all occurs within a substory about a man who was in love with his neighbor's son. The man watched the boy for years but he only touched him once, as the boy's mother recalls.

"What happened was that in the middle of talking, for no reason, he just reached out a finger, very slowly, and touched Steve. With just one finger . . . . It was like, sometimes when you're standing in front of a clean window, a very clean window, looking out, and the window is so clean it looks like it's not there. You know? And to make sure it's there, even though you know it's there, really, you'll reach out and just . . . touch the window, ever so slightly. Just barely touch it. That's what it was like."

This is a wonderful book. ::

Rudy Rucker's recent novels are "Master of Space and Time" and "The Secret of Life." His science books include "The Fourth Dimension" and the forthcoming "Mind Tools."