Card Colm is a bimonthly column sponsored by the Mathematical Association of America.
This column explores mathematical card principles and effects for fun, very much inspired by the extensive writings of Martin Gardner (1914-2010) on the subject, going back to his seminal Mathematics, Magic and Mystery (1956).
Colm Mulcahy has been exploring mathematical card tricks in earnest for over a decade now. For more on this topic, including a guide to material explored in previous Card Colms, see Colm's Cards.
Colm hails from Ireland, where he earned bachelor's and master's degrees in Mathematical Science at UCD. He then went to Cornell — more or less along arcs of two great circles — where he did research in the algebraic theory of quadratic forms for his PhD, under Alex FTW Rosenberg. He is Professor of Mathematics at Spelman College, where he has taught since 1988. Music and food are among his passions.