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# Obituary

## Latest Articles

### The Mathematician Who Sculpted the Shape of Space

Eugenio Calabi, who died on September 25, conceived of novel geometric objects that later became fundamental to string theory.

### How Steven Weinberg Transformed Physics and Physicists

When Steven Weinberg died last month, the world lost one of its most profound thinkers.

### Isadore Singer Transcended Mathematical Boundaries

A former graduate student reflects on how Isadore Singer, who died on February 11, brought together mathematicians, physicists and anyone else interested in the deeper connections between diverse fields.

### John Conway Solved Mathematical Problems With His Bare Hands

The legendary mathematician, who died on April 11, was curious, colorful and one of the greatest problem-solvers of his generation.

### Remembering the Unstoppable Freeman Dyson

Freeman Dyson — physicist, mathematician, writer and idea factory — died on February 28, but his vitality lives on.

### Ann Nelson Took On the Biggest Problems in Physics

The theoretical particle physicist Ann Nelson, who died on August 4 at age 61, was a font of brilliant ideas and a champion of ending discrimination in the field.

### Why Stephen Hawking’s Black Hole Puzzle Keeps Puzzling

The renowned British physicist, who died at 76, left behind a riddle that could eventually lead his successors to the theory of quantum gravity.

### Physicists Mourn Joe Polchinski, Developer of Deep Ideas and Paradoxes

The theoretical physicist Joe Polchinski, who died February 2, left a tremendous professional and personal legacy, says a friend and collaborator.

### Visionary Mathematician Vladimir Voevodsky Dies at 51

Voevodsky’s friends remember him as constitutionally unable to compromise on the truth — a quality that led him to produce some of the most important mathematics of the 20th century.