SAN DIEGO (AP) — A University of California San Diego scientist was able to use his math and physics knowledge to argue his way out of a $400 traffic ticket.

In a paper titled “The Proof of Innocence,” senior research scientist Dmitri Krioukov successfully appealed his failure-to-stop ticket by explaining that he may have appeared to an officer that he didn’t stop when he actually did, according to the Los Angeles Times.

“All you need to know is classical mechanics and a little bit of geometry,” Krioukov told the Times.

The calculations were very simple and took five to ten minutes, and writing the four-page paper took a few hours, Krioukov said.

The time spent on the paper was a minor inconvenience considering the cost of a lawyer and the ticket, he said.

According to Krioukov’s calculations, a car moving at a constant speed can appear to move in the same way as a car that is moving quickly and briefly stops before accelerating again.

Krioukov also told the judge that a campus building obstructed the officer’s view of the incident.

The scientist posted his paper online for any other motorists who may be accused of running a stop sign.