# Mathematical Digest

### Short Summaries of Articles about Mathematics

in the Popular Press

"Can you keep a secret?" by Erica Klarreich. *Nature*, 18 July 2002, pages270-2.

According to the article, if quantum cryptography is used to encrypt electroniccommunication, the answer is yes. The security of many current encryptionalgorithms relies on the difficulty of factoring, but because of the quantummechanics principle that the act of measurement changes that which is beingmeasured, eavesdroppers on quantum communication leave an unmistakable mark onthat communication. Although quantum computers will only be realized far in thefuture, if at all, one researcher is quoted as saying that "quantum computationis very much a reality."

*--- Mike Breen *