For thousands of years, if you wanted to send a secret message, there was basically one way to do it. You’d scramble the message using a special rule, known only to you and your intended audience.

Hard problems are usually not a welcome sight. But cryptographers love them. That’s because certain hard math problems underpin the security of modern encryption. Any clever trick for solving them ...

Recently, I co-authored and published a math paper that solved a 15-year-old mystery. But, unlike a book or a gadget, the work cannot be copyrighted or bought and sold. In fact, my co-author and I ...