All visual art, by definition, exists in space. In addition to interpreting space, at least traditionally, by presenting a window into a fictional world, every painting or photograph, like every sculpture, is a physical object. Even examples of new media with a negligible physical dimension -- video art, for example -- involve hardware such as monitors.

Rarer, though, is work that -- like Jennifer Steinkamp's "Loop," a site-specific sound-and-light environment designed for the Corcoran Gallery of Art's Rotunda -- doesn't just depict or take up room, but transforms it.

The works in "Conversions," a juried group show at the Ellipse Arts Center organized in conjunction with the Washington Project for the Arts/Corcoran, attempt to negotiate these distinctions. Most successful among the varied offerings, which were selected from artist proposals by jurors Sam Gilliam, Dennis O'Neil and Heather and Tony Podesta, is Rene Butler's "Movement in B Flat."

Given a room all to itself, with a door to shut out extraneous sound and light, Butler's two-channel video installation is an immersive experience; you don't watch it so much as feel it. Against a sonic backdrop of seemingly random, toy piano-like plinks (B-flat, naturally) that suggest a John Cage composition, Butler projects quasi-abstract videotaped images from her travels: undulating blue water, strolling pedestrians, fireworks, neon lights, miscellaneous industrial textures, a train.

In a way, it's quite restful. Observed from one of a couple of couches in the room, the images are initially unchallenging; there are no scenes of war or starvation. Yet Butler shatters the seeming placidity of each image, breaking them up into disorienting fragments by means of mirrors and hanging silk panels. Underscored by the music, "Movement" creates an increasing sense of discordance and unease, a cocktail lounge where all the pretty drinks will leave you with a hell of a hangover.

Kathryn Cornelius makes a more direct run at anomie. Constructed in and around what appears to be a closet, the artist's claustrophobic "Address" utilizes even more jarring audio (partially recorded from the screams of roller coaster riders) and an uncomfortable bed of crushed white marble between white picket fencing to make a statement about the violence and trauma that occasionally underlie the quiet domestic exteriors of our homes.

Less political, but no less dramatic, are the spatial transformations of Ami Martin Wilber and Michele Kong. Not unlike the way Jim Lambie's "Zobop," an installation of colored vinyl tape currently adorning the floor of the Hirshhorn Museum and Sculpture Garden's lobby, attempts to eliminate edges, Kong's "Reticula," a lacy "curtain" made entirely of glue, calls into question the notion of "wall" and the transitions between indoor and outdoor space. Wilber's elegant window treatment in coiled wire, "Three Fates," accomplishes something similar.

Other intriguing works include Tomás Rivas's carved drywall panels -- Home Depot as art supply store -- and Susan Eder and Craig Dennis's photographs. In their collaboration, natural cloud formations appear to spell out the letters of "Which Image Never Fades Away?" It's both the work's title and a pretty good question.

Other works fit in less well with the show's theme, including a series of photographs from Joan Sarah Wexler's "Tearooms and Restaurant Interiors" series. They're less about formal space than about social ritual.

Then there's Tai Hwa Goh's intaglio-on-hand-waxed-paper prints. Sure, they benefit from a bit of creative installation -- including use of the gallery floor -- to display the artist's origami-like cubes and ruffles. Unfortunately, they merely displace the air in the room, rather than energize it.

CONVERSIONS Through Sept. 29 at the Ellipse Arts Center, 4350 N. Fairfax Dr., Arlington (Metro: Ballston-MU). 202-228-7710. Open Wednesday-Friday 11 to 7; Saturdays 11 to 2. Free.

Public programs associated with the exhibition include:

Sept. 21 from 7 to 9 Artists' talk.