The Physics of Information

Information is carried, stored, retrieved and processed by machines, whether they be electronic computers or living organisms. All information, which in an abstract sense one may think of as a string of zeros and ones, has to be carried by a physical substrate, be it paper, silicon chips or holograms, and the handling of this information is physical, so information is ultimately constrained by the fundamental laws of physics. It is therefore not surprising that physics and information share a rich interface.

Below: Digital art for IBM Journal cover, based on cryptography,
featuring articles on the ‘Physics of Information’, quantum computing.