Kevin Hartnett
@KSHartnett
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Chief editor @stripe. Formerly math editor @quantamagazine and Brainiac columnist @bostonglobe.
Joined July 2011
RT @fsgbooks: Quanta Books will publish its first book in Spring 2026. Kevin Hartnett’s THE PROOF IN THE CODE is the definitive account of…
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I'm excited to share that my book, "The Proof in the Code," will be the first title released by @QuantaBks, a new imprint from @FSG_books and @SimonsFdn. It's the story of how @leanprover is transforming math research. Coming Spring 2026.
🚨New book announcement!🚨 @KSHartnett's THE PROOF IN THE CODE (coming 2026) tells the gripping story of the birth and rise of Lean, a Microsoft program transforming the world of mathematics. A timely challenge to our assumptions about who–or what–can do math.
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@MIT researchers discovered a riddle: In experiments, running mice stopped faster than observed brain activity justified. The explanation? The brain compares competing signals to take a type of derivative, enabling mice (and humans) to stop on a dime. My piece in @QuantaMagazine.
The brain uses basic calculus to quickly halt fast movements — a surprisingly clever way to control behaviors that need to be more precise than the commands from the brain can be. @KSHartnett reports:
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RT @patio11: If you’d like to read more about card testing specifically, see It has some recent figures about the…
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The circular economy turns one industry (or person's) trash into another's treasure. Fantastic piece this morning on @stripe Newsroom featuring comments from @wef, @BiaSolFoods, @Raeburn_Design, @UrbanOutfitters, and more.
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The first big "proof" I ever covered was Mochizuki's work on the ABC conjecture. Which came out of nowhere. Which made it hard to read and provoked (ultimately warranted) skepticism.
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Today on the @stripe Newsroom we look at how @dwell is thriving with an innovative approach to digital subscriptions and brand extensions...including becoming a homebuilder itself. With quotes from @zachklein.
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Lots of tech optimizations shaping the trucking industry today. We take a look in a new piece on the @stripe Newsroom, with insights from @emilygsands, head of data science at Stripe.
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@AliWolfEcon Hard to know where to set the baseline bc the top was so frothy, but in the towns around Portland ME prices are clearly well off their late-spring highs.
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An amazing discovery wrapped in great story that exemplifies how new knowledge lives (or almost dies) in mathematics. One of my favorite stories I've reported for @QuantaMagazine.
Topology questions are often easier in higher dimensions because mathematicians have more room to maneuver. Dimensions 3 and 4 are tighter and questions there are harder.
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I enjoyed talking with @jeffjarvis for this piece. He makes the point that newspapers need to expand the possibilities for consumer revenue sources and reduce the friction surrounding them.
.@stripe tries to help the news business: The financial future of news
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Legacy newspapers are experimenting with new revenue models. Today on the @stripe Newsroom we take a look at some of the most promising approaches including tipping (@thenewsmovement) and micropayments (@axate).
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@7homaslin I've read a little about this, Tom, but haven't been able to determine: What is the evidence that Niemann cheated? Is it just that it's improbable he beat Carlsen or is there more?
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RT @NautilusMag: Kevin Hartnett (@KSHartnett) digs into the heart of Claude Shannon's theory of information from his epochal 1948 paper, "A…
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I chatted with Richard Rusczyk of @AoPSNews earlier this year and since then, I'm glad to see they've launched Beast 1, which my second-grade son loves. I also enjoyed this conversation between Richard and @EricaKlarreich for @QuantaMagazine.
My kid loved @TheBeastAcademy's math comics, so I was excited to talk to @AoPSNews founder Richard Rusczyk about his ambition to bring the joy of problem-solving into classrooms everywhere:
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For weeks now I've been quizzing my friends: Does it take more information to communicate the results of flipping a loaded coin or a fair coin? Glad to have had a chance to learn the answer while reporting this piece.
In his epochal 1948 paper, “A Mathematical Theory of Communication,” Claude Shannon mathematically quantified the amount of information needed to accurately send and receive a message. @KSHartnett explains how this information entropy works:
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"You can teach a physicist finance but you cannot teach a finance person physics." Feeling grateful to the @googlenews algorithm for finding me this recent interview with Jim Simons, @SimonsFdn.
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