Somebody Else's Problem field
From Wikipedia, the free encyclopedia
The Somebody Else's Problem field (SEP field) is a fictional technology from The Hitchhiker's Guide to the Galaxy "trilogy" by Douglas Adams. It is a cheaper and more practical alternative to an invisibility field.
[edit] Concept
An SEP field is a generated energy field which affects perception. Entities within the field will be perceived by an outside observer as "Somebody Else's Problem", and will therefore be effectively invisible unless the observer is specifically looking for the entity. This effect is greatly heightened if the entity within the field is already unexpected or out of place. The primary example of this was given in the third book Life, the Universe and Everything, when a spaceship built to look like an upside down bistro utilizes a SEP field to land unobserved in the middle of Lord's Cricket Ground. Another example occurs when the aforementioned ship's field is extended so that the characters fail to notice the fact that they cannot breathe or the fact that the asteroid that they are standing on does not have enough gravitational force to hold them down, and thus are able to breathe and stay grounded. It should be noted that a SEP field won't render an object invisible if it is expected to be there, and an SEP-cloaked object may be noticed out of the corner of the eye.
The SEP field requires much less energy than a normal invisibility field (a single torch battery can run it for over a hundred years) due to the natural propensity of people to see things as Somebody Else's Problem. This is very close to the idea suggested by Terry Pratchett (who has often been compared to Douglas Adams): people do not see whatever they are sure cannot be there.
A similar concept is shown on the BBC programme Torchwood when Captain Jack Harkness and Gwen Cooper rise out of the pavement in the middle of Roald Dahl Plass in Cardiff on Torchwood Three's "invisible lift" and are completely ignored by the people around them due to what he describes as a 'perception filter'.
[edit] Real life example
The idea of the SEP field has some grounding in the real life idea known as static filtering, in which people immediately disregard information contrary to what is expected. An example of malicious use of static filtering is the theory of subliminal messages in visual media. This theory is also put to practice in the film Fight Club; viewers are shown brief glimpses of a specific character as he suddenly appears and disappears, yet first-time viewers will generally disregard the flash unless they are told about its significance.
There exists a related phenomenon known as inattentional blindness. Essentially, when a person is paying close attention to a specific object or task, they are unlikely to remember anything else about the scene. This was reported on clearly by Daniel J Simons and Christopher F Chabris of Harvard University in their study "Gorillas in our midst: sustained inattentional blindness for dynamic events" (Harvard University, 1999). This study discusses subjects who were told to carefully watch a televised basketball game and count the number of passes made or other similar tasks. Most of the subjects failed to notice when the scene changed in various ways, such as the ball being thrown off court (with the players continuing to mimic passes), or exchanging all the male players for women. In the most dramatic example, nearly half the viewers failed to notice a woman carrying an umbrella and a man in a gorilla suit walking across the screen in the middle of the video.
