LONELY HEARTS OF THE COSMOS The Scientific Quest for the Secret of the Universe By Dennis Overbye HarperCollins. 438 pp. $25

MODERN COSMOLOGY is seething with controversy. New observations keep demolishing old theories, while fantastic new theories sprout like mushrooms. Books, too, are proliferating to meet public curiosity about what is going on. To Dennis Overbye, a science writer who calls himself a "cosmological camp follower," astronomers are a lonely breed. They are lost in the immensity of the universe, battered by the unexpected data pouring out of giant telescopes, and in perpetual conflict with one another.

Overbye's account differs from similar popular books by going into more technical details, and by stressing the appearances and personalities of the leading combatants now struggling to read, as Stephen Hawking has put it, the Mind of God. Swarming with anecdotes, Overbye's book -- it is his first -- is written with such wit and verve that it is hard not to zip through it at one sitting.

Although most of today's cosmologists are covered, the book's central figure is Iowa-born Allan Sandage, who began his legendary career as a disciple of the great Edwin Hubble. It was Hubble who first confirmed Kant's bold conjecture that nebulae are vast islands of stars, and who found that these billions of galaxies are rushing away from one another. Einstein's first model of the cosmos was a static one, prevented from collapsing by what he imagined to be a repulsive force. After the "Hubble flow" became obvious, Einstein called his conjecture the greatest blunder of his life. His model remained closed, like a sphere's surface, but enlarging like an inflation balloon. This expansion clearly implied a moment of creation, or what Fred Hoyle derisively called the Big Bang.

Hoyle's rival theory, the Steady State, had hydrogen atoms constantly entering space from somewhere to preserve an expanding universe that has always been and always will be overall the same. His theory exploded with a bang after the microwave radiation from the primeval fireball was detected.

In Overbye's racy account of this, and of the battles that followed, we are told that Sandage "haunts" the narrative "simply because he has been doing cosmology, trying to solve the universe, so much longer and more intensely than anyone else." I do not know how accurate Overbye's picture of Sandage is, but no one emerges from the book in more incisive detail -- a person Overbye sums up as "a cosmic quipster, edgy as a razor, scat quick, and humorously dry as a lemon."

Sandage's great contributions are set forth for the first time in detail, alongside his many bitter conflicts with colleagues. "You weren't anybody in astronomy," Overbye writes, "if Sandage hadn't stopped speaking to you at one time or another." For years he and Halton ("Chip") Arp were irreconcilable enemies. Arp continues to be a pebble in the shoes of cosmologists because he keeps finding evidence that quasars may not be far distant objects of enormous energy, but nearby objects of low energy. If he is right, the red shift is an unreliable measure of distance and all modern cosmology is wrong.

Hawking, John Wheeler, Roger Penrose, Dennis Sciama, Robert Dicke, Allan Guth, Margaret Geller -- these are just a few of the top cosmologists who weave in and out of Overbye's colorful history. Most of them believe in black holes, but are these invisible monsters really crouching out there, or are they just dubious extrapolations from relativity theory as Philip Morrison suspects? "Black holes are out of sight," reads a sign on Hawking's door. You will learn why Hawking thinks they are not totally black, but radiating energy, and why he thinks the universe may be peppered with tiny black holes that eventually will explode.

You will learn about Vera Rubin's shrewd deduction from the way galaxies rotate that the universe must be saturated with invisible "dark matter." The nature of this matter, and whether it is massive enough to halt the universe's growth and start it shrinking are unsolved mysteries. If there is a Big Crunch, will the universe bounce back or will it "drag itself into oblivion" to become, in another Overbye metaphor, eaten by God?

You will learn about recent evidence that the galaxies are not randomly distributed, but form a soapsudsy structure. Cosmologists are working hard on far-out theories to explain this lumpiness, and why so many local galaxies are streaming the wrong way, against the Hubble flow.

The most bizarre of recent speculations is that the universe spontaneously emerged from nothing. But of course it isn't really nothing because there must have been laws of physics to give the almost nothing what Overbye calls the "twitch" that exploded some 15 billion years ago into our time and space, and a universe capable of producing such peculiar life forms as you and me.

Only a few cosmologists, Sandage among them, have the courage to go against the scientific community's zeitgeist by entertaining the wild notion that basic laws are in God's Mind. Although impressed by the awesome mystery of existence, most cosmologists seem to agree with such atheists as Bertrand Russell that nothing is gained by positing an eternal Creator when eternal laws will do the job just as well.

"Astronomy is an impossible science," Sandage said to Overbye. "It's a wonder we know anything at all."

Martin Gardner is the author of "The Relativity Explosion" and other books about science, mathematics, philosophy and literature. His latest book is "More Annotated Alice."