# Verifying a Claimed Counterexample to the Jacobian Conjecture

DevFeed: [Verifying a Claimed Counterexample to the Jacobian Conjecture](<https://devfeed.tech/articles/trust-nothing-verify-everything-reproducing-the-jacobian-counterexample-from-my-couch-40145.md>)

Original publisher: [Read original article](<https://korbonits.com/blog/2026-07-20-trust-nothing-verify-everything/>)

Published: 2026-07-20T00:00:00Z

Content type: opinion

Language: en

Sources: [Alex Korbonits](<https://devfeed.tech/sources/alex-korbonits.md>)

Topics: [trust](<https://devfeed.tech/topics/trust.md>), [Claude](<https://devfeed.tech/topics/claude.md>), [anthropic](<https://devfeed.tech/topics/anthropic.md>)

Tags: [claude](<https://devfeed.tech/tags/claude.md>), [model](<https://devfeed.tech/tags/model.md>), [trust](<https://devfeed.tech/tags/trust.md>), [verify](<https://devfeed.tech/tags/verify.md>)

## AI overview

The author examines a claimed counterexample to the long-standing Jacobian conjecture, posted in a tweet and attributed to Anthropic's Claude model. They describe checking the polynomial map's constant Jacobian determinant and non-invertibility using symbolic calculations, while noting that no paper or referee report was available.

## Source excerpt

The Jacobian conjecture fell yesterday, during the World Cup final, via a tweet. Wikipedia still says it's open. Here's how I checked it myself in two cells of sympy -- and why the fact that I could is the real story.