The images penetrate. Michael, sometimes known as Shelly, whippet thin, shirtless, kohl-smeared rings around her eyes, extends a rosary toward the camera like an offering. Sarah’s green T-shirt pulls taut over the curve of her shoulder as she bends to insert a needle into the back of her hand. Tears squeeze out of Sonya’s swollen eyes, her face ragged and red; in her arms, she cradles a small black kitten. And in an almost surreal scene, Takeesha and Deja, dressed in the brightly colored knits and laddered leggings of sex workers, peer at Saturn’s rings through a telescope set up in a city alley.

The photography of Chris Arnade, PhD ’94, as seen in his Flickr series, “Faces of Addiction,” as well as on his blog and Facebook page, exposes a range of human experience in the Hunts Point neighborhood of the South Bronx, most of it inseparable from the ravages of heroin addiction that affect the people in this community, whom Arnade regards as friends. The images are raw and provoke a range of reactions—from sympathy to anger to disparagement—from those who view his work. The text accompanying the photos attempts to make order of the chaos of street life and of Arnade’s own shifting consciousness. “I am a believer in withholding judgment and being open to suggestions,” he writes in the post below Sonya’s picture. “This is not one of those times. I will tell everyone I know and anyone who will listen. DON’T EVER DO HEROIN. EVER.”

How did someone with a PhD in physics and a two-decade career on Wall Street become a chronicler of urban street life? Blame it on a predilection for long walks in neighborhoods where most outsiders never venture, a love of photography as a way of engagement in unfamiliar environments, and a profound vocational shift.

“I was always drawn to neighborhoods I was told not to go to,” explains Arnade, who says he enjoyed his first 10 years on Wall Street as a trader. “But after the [finance] culture shifted, I started finding myself not being sure this was the right thing to do with my life.

“I spent more and more time walking. And I found myself in Hunts Point photographing the people I was talking to.”

Fourteen months ago, Arnade decided to quit his full-time job, live off of his savings for a while, and spend more time in this deeply challenged community. Since then, Arnade has photographed Hunts Point’s pigeon keepers and street hustlers, stray cats, sex workers, and men and women deep in the throes of heroin addiction. He visits the neighborhood daily, leaving his house in the late afternoon or early evening and returning home well after midnight to write his blog and post photos.

Arnade had explored and photographed unfamiliar neighborhoods prior to Hunts Point. He recalls his first weekend in Baltimore, in 1987, where he’d come to study at Hopkins. He left his house on Guilford Avenue, walked south down Greenmount and then across North Avenue to Broadway down to Fells Point. It was the first of many long walks in Baltimore.

“It was never meant to be a project,” he says of his Hunts Point work, which he admits is hard to categorize. “The whole point was to take respectful pictures to force you to look at people. …Pictures were a good way to force people to read.”

Raising awareness and initiating conversations about addiction, homelessness, and abuse has clearly become a goal of his work. Arnade’s Facebook page has 20,000 followers and his Flickr page has garnered more than 20 million views. He is considering writing a book about his experiences. And he also has ideas about buying a house that would be converted into what he calls a harm reduction center. “Addicts can’t get clean until they want to get clean,” Arnade says matter-of-factly, “but small things—like Internet access or information on detox centers, just a safe place—can make their lives better and give them some equilibrium.”

While Arnade may have left Wall Street and physics behind, the latter hasn’t entirely left him. He uses physics analogies in conversation, comparing the micro detail of life he sees in Hunts Point to “looking at particles…the quark, as it were.” And he keeps his telescope with him in his car, and gets immense pleasure introducing people who have never seen the moon or the planets up close to the instrument. Arnade recalls an early morning when he was trying to help a woman who had been sleeping in her car and was “distracted by the sky and the rising nebula—a jarring reminder of the very different things that are going on in my life,” he says. “There are times I feel guilty about the immense beauty you can see and the immense pain beneath it.”