"The cameras are literally everywhere," he said. "But when you turn the camera around, you reclaim that public space."
That's a topic that Elahi explores with his College Park students, freshmen and sophomores who are majoring in a broad range of topics but who share an interest in art and technology. The students have grown up with social networking sites and are constantly grooming what Elahi calls their "digital doppelgangers."
"How do you manage your online identity? It's something I talk about with my students all the time," he said. In other words, he said, if people fail to monitor their online personas, the Internet might portray them inaccurately.
Meanwhile, other personal information is being tracked by various entities. Anyone who uses a cellphone, searches in a web browser or swipes a credit card leaves a trail of easily accessible data, said Jeramie Scott, a national security fellow with the Electronic Privacy Information Center, a District of Columbia-based watchdog group.
Government investigators don't need warrants to sift through much of that information, such as the records tracking your Internet preferences that are sold to advertisers. Surveillance cameras — those operated by police and private businesses — license plate readers and EZ-Pass toll booths can all be used to track movements of people or vehicles, he said.
And short of giving up cellphones, computers and bank cards, there are few ways to hide, said Scott.
"If you really wanted to protect your privacy, you'd really have to go off the grid," he said.
Elahi likes to think of himself as hiding in plain sight. While he has posted a plethora of information about himself online — his site even includes photos of urinals and toilets he has used — he reveals little insight into his personal life.
"You can't necessarily delete, but you can bury," he said. "It basically becomes camouflage — a massive amount of noise."
A sense of loneliness pervades Elahi's images, in part because he intentionally avoids photographing people. Subway platforms and airport waiting lounges are empty, save for a few people lingering far away. Hallways gleam, but no one casts a shadow in the stark lighting. The only hint of the presence of others are shots that show two plates of food or a bed rumpled on both sides.
But, says Elahi, a close observer could pick out clues to his intimate world. When he adopted a cat, shots of a cat box appeared. After his fiancee moved in with him, she hung new curtains in their apartment.
As Elahi sees it, the fascination with being observed — and ducking observation — is an integral part of human identity.
"The concept of surveillance is ingrained in our beings," he said. "God was the original surveillance camera."