Ansible

An ansible is a category of fictional device or technology capable of instantaneous or superluminal (faster than light) communication. It can send and receive messages to and from a corresponding device over any distance whatsoever with no delay. The term ansible is broadly shared across works of several science fiction authors, settings and continuities.

Ursula K. Le Guin coined the word ansible in her 1966 novel Rocannon's World. Le Guin states that she derived the name from the word "answerable", as the device would allow its users to receive answers to their messages in a reasonable amount of time, even over interstellar distances. Her award-winning 1974 novel The Dispossessed, a book in the Hainish Cycle, tells of the invention of the ansible.

The name of the device has since been borrowed by authors such as Orson Scott Card,Vernor Vinge,Elizabeth Moon,Jason Jones,Kim Stanley Robinson,L.A. Graf, and Dan Simmons.

Similar devices are present in the works of numerous others, such as Frank Herbert and Philip Pullman, who called his a lodestone resonator.

Anne McCaffrey's Crystal Singer series posited an instantaneous communication device powered by rare "Black Crystal" from the planet Ballybran. Black Crystals cut from the same mineral deposit could be "tuned" to sympathetically vibrate with each other instantly, even when separated by interstellar distances, allowing instantaneous telephone-like voice and data communication. Similarly, in Gregory Keyes' series The Age of Unreason, "aetherschreibers" use two halves of a single "chime" to communicate, aided by scientific alchemy. While the speed of communication is important, so is the fact that the messages cannot be overheard except by listeners with a piece of the same original crystal.

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