Markov Chain Norris May 2026

He began to write a different chapter instead. He called it The Weight of Yesterday: Why the Past Always Returns .

To his astonishment, she laughed—a small, broken sound. “You’re such an asshole, Dad.”

On the last morning, the sun broke through the Cambridge rain. Chloe died at 7:43 a.m., with her hand in his. Alistair Norris returned to his college rooms. He sat at his desk. The silver die-shaped letter opener lay where he’d left it. He opened the drawer marked "Past States." Inside, beneath a folded program from a long-ago conference, was the postcard of the Maine lighthouse. markov chain norris

The rain over Cambridge was the kind that didn’t fall so much as seep—into coats, into bones, into the very margins of notebooks left too long on park benches. Professor Alistair Norris, aged forty-seven, holder of the Chair in Stochastic Processes, stood at the window of his college rooms and watched the students scatter like particles undergoing Brownian motion.

He was a man who believed in the elegance of forgetting. Not memory loss, but conditional independence : the future should depend only on the present, not the past. It was the central tenet of his life’s work—the Markov chain. And for twenty-three years, he had applied it to everything: the movement of gas molecules, the rise and fall of stock prices, the shuffling of a deck of cards. Even to himself. He began to write a different chapter instead

This was the Norris method: a man as a memoryless process. It was clean. It was mathematical. It was, he believed, the only rational way to live.

He put on his coat. The hospital smelled of antiseptic and overcooked carrots. Ward 14 was a long, fluorescent-lit room with six beds. Chloe was in the third. She was thirty-four, but she looked sixty. Her hair was gone. Her skin was the color of damp paper. Tubes ran from her arms like tributaries of a sad river. “You’re such an asshole, Dad

“I should have come sooner,” he said. “I should have never stopped.”