By cleverly cross-referencing different databases it can be possible for evil adversaries to reveal intimate information about individuals. Given that it's hard these days to keep your details off these databases, what can be done to protect privacy? We talk to Cynthia Dwork from Microsoft, whose talk at the ICM showcases some mathematical tools to keep our details safe.
Researchers from the University of Maryland have devised a new kind of random number generator that is cryptographically secure, inherently private and — most importantly — certified random by the laws of physics. Randomness is important, particularly in the age of the Internet, because it guarantees security. Valuable data and messages can be encrypted using long strings of random numbers to act as "keys", which encode and decode the information. Randomness implies unpredictability, so if the key is truly random, it's next to impossible for an outsider to guess it.
David Spiegelhalter explains that waiting for an infinite number of monkeys to produce the complete works of Shakespeare is not just a probabilistic certainty, it also gives us an insight into how long we can expect to wait for a rare event to happen.
Numbers like Pi have no repeating pattern. So just how accurately do we know what it is?