Do you remember our April Fool's Day news story last month? In the spoof article, we pretended that the UK's new 50p commemorative coin,which contains Stephen Hawking's famous equation for the entropy of a black hole, contained an error. We claimed that the mistake had been discoveredby 14-year-old French mathematical-physics prodigy "April Lapremiere". She found, we pretended, that Hawking had been out by a factor of two and thatthe coin should have had a "2" on the denominator, rather than a "4". The coin, we lied, was now being withdrawn.

The joke should have been obvious as we laid it on pretty thick. Unfortunately, it went over the head of one reader - Jacob L (who is tooembarrassed to have his full name revealed). A coin-collecting "warehouse grunt" with a keen interest in science, but no formal training, he e-mailedus this week to say he'd heard about the coin and had been interested in getting one for his personal collection. "But when I saw the article byApril Lapremiere, detailing how the coin was recalled due to an error in the equation, I quickly bought two of the silver proof coins for $300," hewrote. "How I wish I knew French! I didn't see the date, nor did I understand that it was a joke - I am no mathematician!"

Part of the problem for Jacob L was that we always "unpublish" our April Fool's stories before 1 April is over to, er, avoid people getting thewrong end of the stick. But not having a way to track down the story, he later could not quite remember what we had written. And that's when hedecided to fork out for two of the coins, which might well have risen in price due to their future rarity (if the story had at all been true).Fortunately, Jacob L saw the funny side and is happy to share his cautionary tale with other readers. "If the story can make someone laugh (though atmy expense), it is worth sharing," he signed off. "Next year, I'll be a bit sharper come April first..."

To read the complete article, see:
Hawking jokeinspires coin collector, Chaos the lion has radiotherapy, how to coil a liquid jet(https://physicsworld.com/a/hawking-joke-inspires-coin-collector-chaos-the-lion-has-radiotherapy-how-to-coil-a-liquid-jet/)

To read an earlier E-Sylum article, see:
NEW STEPHEN HAWKING 50-PENCE COIN(https://www.coinbooks.org/v22/esylum_v22n12a28.html)