John Cacioppo, Who Studied Effects of Loneliness, Is Dead at 66

She was a brain researcher and an authority on the scientific basis of love. He, too, was a neuroscientist, but with an expertise in loneliness. She was in her mid-30s, he in his late 50s.

Both were wedded to careers in separate hemispheres — until they happened to be seated beside each other, serendipitously, at dinner on the last night of a neuroscience research symposium in Shanghai.

Before going their separate ways, they left the restaurant together. A romantic full moon was rising over the East China Sea. He snapped a photograph. A few weeks later, she emailed him to request a copy (which she later admitted was just a pretext to resume their brief acquaintance).

She, Stephanie Ortigue, was conducting research at the University of Geneva in Switzerland at the time. He, John T. Cacioppo, was doing the same at the University of Chicago. They timed their sporadic subsequent dates to coincide with other scientific conferences.

She fell in love. He felt lonely without her. Within eight months they were engaged. In 2011, they married.