Mathematician, popular science writer, and sf novelist Ian Stewart will be __Science Guest at Worldcon 75__ in Helsinki.

An Emeritus Professor of Mathematics at the University of Warwick, England, Stewart is an active research mathematician __with over 180 published papers__.

He also is one of the UK’s most prolific popularizers of mathematics and has published more than 120 books on various fields of science. He wrote the “Mathematical Recreations” column for *Scientific American* from 1991 to 2001.

He co-authored *The Science of Discworld* with Terry Pratchett and Jack Cohen, a 2000 Hugo nominee, as well as three sequels, *The Science of Discworld II: The Globe, The Science of Discworld III: Darwin’s Watch*, and *The Science of Discworld IV: Judgement Day*. Each book follows a *Discworld *story with scientific exposition. Pratchett made Stewart and Cohen both “Honorary Wizards of the Unseen University” at the same ceremony where the University of Warwick gave Pratchett an honorary degree.

Stewart also has written two science fiction novels with Cohen, *Wheelers *and *Heaven*, and one of his own called *Jack of All Trades*. His latest novel *The Living Labyrinth* (with Tim Poston) came out last year with a sequel on the way.

Stewart finds that writing in more than one mode has benefits. “Writing for a different audience makes you rethink everything – often you find that as you try to explain things to an audience who do not understand things perfectly well, you realize you don’t understand it as well as you thought. And so you get feedback in both directions.”

Ooh, very cool. Maybe he can be talked into presenting a panel or two on “catastrophe theory” in everyday life, or something cool along those lines.