Cryptographers want to know which of five possible worlds we inhabit, which will reveal whether truly secure cryptography is even possible. Many computer scientists focus on overcoming hard computational problems.

Cryptographers want to know which of five possible worlds we inhabit, which will reveal whether truly secure cryptography is even possible. Many computer scientists focus on overcoming hard computational problems.

It's a testament to Turing's fascination with nearly everything that 76 years since his first major paper, there's still so much to write about his work. Expect this week to offer more events and glimpses into these projects: Neuro-computational studies into the functional basis of cognition. The ever forward march for genuine artificial intelligence. New methods of simulating the complexity of biological forms nearly 60 years after Turing's paper on the chemical basis of morphogenesis (indeed this area of complexity theory is now an established area of major research). The slippery mathematical formalist discoveries which define what can or cannot be computed. And not forgetting key historical developments in cryptography, perhaps the field which Turing is most respected for. Moreover, Turing wasn't just one of the greatest mathematicians of the 20th Century, but also one of the greatest creative engineers; someone who wasn't afraid of putting his ideas into automation, through the ne

Gleick makes his case in a sweeping survey that covers the five millenniums of humanity’s engagement with information, from the invention of writing in Sumer to the elevation of information to a first principle in the sciences over the last half-century or so. It’s a grand narrative if ever there was one, but its key moment can be pinpointed to 1948, when Claude Shannon, a young mathematician with a background in cryptography and telephony, published a paper called “A Mathematical Theory of Communication” in a Bell Labs technical journal. For Shannon, communication was purely a matter of sending a message over a noisy channel so that someone else could recover it. Whether the message was meaningful, he said, was “irrelevant to the engineering problem.” Think of a game of Wheel of Fortune, where each card that’s turned over narrows the set of possible answers, except that here the answer could be anything: a common English phrase, a Polish surname, or just a set of license plate numbers

Steganography is the art and science of writing hidden messages in such a way that no one, apart from the sender and intended recipient, suspects the existence of the message, a form of security through obscurity. The word steganography is of Greek origin and means "concealed writing" from the Greek words steganos (στεγανός) meaning "covered or protected", and graphein (γράφειν) meaning "to write". The first recorded use of the term was in 1499 by Johannes Trithemius in his Steganographia, a treatise on cryptography and steganography disguised as a book on magic. Generally, messages will appear to be something else: images, articles, shopping lists, or some other covertext and, classically, the hidden message may be in invisible ink between the visible lines of a private letter.

The advantage of steganography, over cryptography alone, is that messages do not attract attention to themselves. Plainly visible encrypted messages—no matter how unbreakable—will arouse suspicion, and may in