Simply as a technical exercise, Alfonso Cuaron’s outer-space survival story is as amazing an accomplishment as “2001: A Space Odyssey” was forty-five years ago. But though it’s filled with breathless action (presumably not only to generate excitement but also to obscure the implausibility that builds to unbearable proportions by the end), “Gravity” offers no larger a sense of humanity, and far less one of mystery and awe, than Kubrick’s masterpiece did.

The narrative is an extremely simple one. Three American astronauts are working on the exterior of their craft in orbit over earth. The veteran commander, Matt Kowalksi (George Clooney), makes wisecracks as he shoots about using his suit’s jet pack. A second, Shariff (Phaldut Sharma), is but a speck in the distance while he fiddles with what look to be a solar panel. The third, scientist Ryan Stone (Sandra Bullock), is installing some sort of innovative gizmo of her own devising among the external instruments, though there seems to be a problem that will require adjustment.

Suddenly Houston, in the voice of Ed Harris, orders the crew to immediately abort their mission. A collision of a Russian rocket with a satellite has left debris in its wake, causing a chain reaction that’s sending masses of metal hurtling through space, and perhaps toward the Americans. Before they can scramble back into the ship, the debris field hits, killing Shariff and severing the tether that connects Stone to the ship. Adrift in space, she’s eventually saved by Kowalski, but with their vessel inoperable, they’re forced to make their way to a nearby Russian space station. In the process Kowalski sacrifices himself with nonchalant courage, leaving Stone to try to maneuver a damaged escape pod to another possible refuge, a Chinese station, and then find some means of getting back to earth.

The physical depiction of all this is simply stunning; Cuaron seems to take special delight in challenging Kubrick on his own turf (or off it, since it’s all in space) and doing him not one but several steps better. So the opening sequence outside the shuttle, with the camera waltzing around the action, is leagues beyond the “Blue Danube” ballet between the space shuttle and the revolving circular station of “2001,” and that in which Kowalski retrieves the spinning, tumbling Stone is a much more complicated reworking of the one in which Keir Dullea’s Bowman tracks down Poole’s inert corpse. He certainly shows the enormous advances made in special-effects technology over the decades, and seizes on the possibilities with a master’s touch, both in those two sequences and the ones in which Bullock swims in zero gravity, stripped down to her skivvies in what might be a homage to “Alien,” through the corridors of the space stations as bits of debris float around her and puffs of flame shoot out from a short that will lead to an explosion.

But while one must marvel at what the film achieves visually, it becomes increasingly evident that it offers nothing more than a simple-minded survival story in which characterization doesn’t get beyond the sketch pad. Though Clooney can deliver even the banalities Cuaron and his son Jonas have devised for Kowalski with engaging flippancy, in the end the commander is merely a stock figure whose main function is to encourage Stone to keep struggling. More effort is made to invest Ryan with depth, but the means employed—the revelation of a domestic tragedy in her past that threatens her will to live—is trite, and in the end Bullock doesn’t give the character much more than a generalized teeth-gritting determination. (The final scene, which is meant to symbolize her rebirth—and perhaps that of humanity itself—falls flat in more ways than one. Given the escalating implausibility at each stage along Stone’s journey—especially in a sequence when she miraculously escapes harm from yet another debris assault—one wonders whether it might not have been better for the script to go the way of William Golding’s “Pincher Martin,” a survival story with a far darker concluding twist.) In fact, the most intense human feeling in the entire film comes when Cuaron focuses on a photo of Shariff’s family on his lifeless body, which captures for an instant the real cost of his loss.

Of course, one can observe that the characters in “2001” were even less developed that those here. That’s fair enough, but also beside the point. Kubrick’s Bowman and Poole weren’t intended to be “human” in the conventional dramatic sense; they were symbols of a mankind from which passion had been drained in favor of cool calculation and pure techno-pragmatism. That’s not the case with Cuaron’s characters, with whom we’re meant to identify on an emotional level, but can’t because they’re so casually drawn.

The result is a film that is perhaps more representative than any other similarly extravagant piece of technical wizardry—“Avatar,” say, of “The Life of Pi”—of the reality that in cinema today technique is, if not everything, the main thing. “Gravity” is an astonishing technical tour de force and an exciting thrill ride, but as a human drama it barely registers, and it carries none of the metaphysical weight of a film like “2001,” however one might assess Kubrick’s ambitions to profundity. Recognition is certainly due Cuaron, cinematographer Emmanuel Lubezki, production designer Andy Nicholson, art direction Mark Scruton, the special effects team led by Neil Corbould and Manex Efrem, and the visual effects crew supervised by Tim Webber and Charles Howell, who all worked together to fashion a world incredible in its detail and complexity—as well as for using the 3D format with such vividness and subtlety, especially on an Imax screen. But one winds up admiring their film for its technical virtuosity while regretting that ultimately it’s devoid of any ideas of consequence.