Erica Klarreich

Freelance Mathematics and Science Journalist

Berkeley, California

Erica Klarreich

My work has appeared in Quanta, Nature, New Scientist, Science News, and many other publications, and has been reprinted in the 2010, 2011, and 2016 volumes of "The Best Writing on Mathematics."


How to Quantify (and Fight) Gerrymandering

April 4, 2017 — Powerful new quantitative tools are now available to combat partisan bias in the drawing of voting districts.
Quanta Magazine Link to Story

Graph Isomorphism Vanquished — Again

January 14, 2017 — It’s been a whiplash-inducing couple of weeks for theoretical computer scientists. On January 4, László Babai, a professor at the University of Chicago, sent shock waves through the community by retracting a claim which, back in November 2015, researchers had hailed as the theoretical computer science advance of the decade.
Quanta Magazine Link to Story

Complexity Theory Problem Strikes Back

January 5, 2017 — The theoretical computer scientist László Babai has retracted a claim that amazed the computer science community when he made it just over a year ago. In November 2015, he announced that he had come up with a “quasi-polynomial” algorithm for graph isomorphism, one of the most famous problems in theoretical computer science.
Quanta Magazine Link to Story

Learning Securely

November 8, 2016
Communications of the ACM Link to Story

All Is Not Fair in Cake-Cutting and Math

October 7, 2016 — A pair of computer scientists recently settled one of the key questions in the theory of fair division: How can you allocate cake slices among a group of people in such a way that no one envies anyone else? Yet envy-freeness is just one of several competing notions of fairness. It’s all well and good to divide a cake in a way that won’t produce envy, but you might instead want to find an “efficient” allocation, one that can’t be improved for anyone without harming someone else.
Quanta Magazine Link to Story

How to Cut Cake Fairly and Finally Eat It Too

October 6, 2016 — Two young computer scientists have figured out how to fairly divide cake among any number of people, setting to rest a problem mathematicians have struggled with for decades. Their work has startled many researchers who believed that such a fair-division protocol was probably impossible. People have known at least since biblical times that there’s a way to divide such an object between two people so that neither person envies the other: one person cuts the cake into two slices that she values equally, and the other person gets to choose her favorite slice.
Quanta Magazine Link to Story

The Oracle of Arithmetic

June 28, 2016 — In 2010, a startling rumor filtered through the number theory community and reached Jared Weinstein. Apparently, some graduate student at the University of Bonn in Germany had written a paper that redid “Harris-Taylor” — a 288-page book dedicated to a single impenetrable proof in number theory — in only 37 pages.
Quanta Magazine Link to Story

Simple Set Game Proof Stuns Mathematicians

May 31, 2016 — In a series of papers posted online in recent weeks, mathematicians have solved a problem about the pattern-matching card game Set that predates the game itself. The solution, whose simplicity has stunned mathematicians, is already leading to advances in other combinatorics problems. Invented in 1974, Set has a simple goal: to find special triples called “sets” within a deck of 81 cards.
Quanta Magazine Link to Story

Sphere Packing Solved in Higher Dimensions

March 30, 2016 — In a pair of papers posted online this month, a Ukrainian mathematician has solved two high-dimensional versions of the centuries-old “sphere packing” problem. In dimensions eight and 24 (the latter dimension in collaboration with other researchers), she has proved that two highly symmetrical arrangements pack spheres together in the densest possible way.
Quanta Magazine Link to Story

Mathematicians Discover Prime Conspiracy

March 13, 2016 — Two mathematicians have uncovered a simple, previously unnoticed property of prime numbers — those numbers that are divisible only by 1 and themselves. Prime numbers, it seems, have decided preferences about the final digits of the primes that immediately follow them. Among the first billion prime numbers, for instance, a prime ending in 9 is almost 65 percent more likely to be followed by a prime ending in 1 than another prime ending in 9.
Quanta Magazine Link to Story

Landmark Algorithm Breaks 30-Year Impasse

December 14, 2015 — A theoretical computer scientist has presented an algorithm that is being hailed as a breakthrough in mapping the obscure terrain of complexity theory, which explores how hard computational problems are to solve. Last month, László Babai, of the University of Chicago, announced that he had come up with a new algorithm for the “graph isomorphism” problem, one of the most tantalizing mysteries in computer science.
Quanta Magazine Link to Story

‘Outsiders’ Crack 50-Year-Old Math Problem

November 24, 2015 — In 2008, Daniel Spielman told his Yale University colleague Gil Kalai about a computer science problem he was working on, concerning how to “sparsify” a network so that it has fewer connections between nodes but still preserves the essential features of the original network. Network sparsification has applications in data compression and efficient computation, but Spielman’s particular problem suggested something different to Kalai.
Quanta Magazine Link to Story


Erica Klarreich

I have been writing about mathematics and science for a popular audience for more than fifteen years. A mathematician before I became a full-time journalist, I try to convey the essence of complex mathematical ideas to non-mathematicians, and give them a sense of the beauty and depth of mathematics.

I also enjoy plunging into topics far from my mathematical roots, and have written about fields such as economics, computer science, medicine, and biology — often as these fields relate to mathematics, but often simply for their own sake.

As a freelance journalist based in Berkeley, California, I have written for many publications, including Nature, Quanta Magazine,, New Scientist, American Scientist,, Nautilus, and Science News, for which I was the mathematics correspondent for several years. I was also the Journalist in Residence at the Mathematical Sciences Research Institute in Berkeley. My work has been reprinted in the 2010, 2011, and 2016 volumes of "The Best Writing on Mathematics."

I am a graduate of the science writing program at the University of California, Santa Cruz, and I have a Ph.D. in mathematics from Stony Brook University.

For the Fall 2016 semester, I am the Journalist in Residence at the Simons Institute for the Theory of Computing at the University of California, Berkeley.

Contact me at

Follow me on Twitter at @EricaKlarreich