Time viewer
The Time viewer is a fictional device often used in science fiction. It is usually a device which functions along the same lines as a television, except that the picture depicts events in another time, either the past or the future. The device is also often called a chronoscope, but this name has also been used by the Victorian scientist, Charles Wheatstone.
In stories where time travel is a major plot element, the ability to view the happenings at another time is simply a side effect of the technology, and is little noted. An exception is "Millennium" by John Varley, where the time viewer's behavior (or misbehavior) is an important plot element. For reasons of "temporal censorship" the viewer cannot see into times where the travellers have been or will be, even if the location was far away. Also, the creation of a paradox results in progressive blurring of the image as alternate futures overlap.
Robert Heinlein's seminal time-travel story "By His Bootstraps" features a "time portal" with viewing capability, created by a future race of aliens which reduced humans to docile servants, ripe for exploitation by a 20th century go-getter. The protagonist eventually uses the viewer to see the aliens before they left Earth, but the experience almost unhinges his mind. It is while idly viewing his own home time period that he sets into motion the paradoxes that lead to him attaining his new life.
Other stories feature the time viewer, or some similar technology, as the principal plot element. The best known is The Dead Past, by Isaac Asimov which concerns the clandestine creation of a time viewer when research into the subject is mysteriously suppressed. The reason for this is revealed at the end - the mere existence of a time viewer destroys all notions of privacy, since the device can be used to view events happening only a fraction of a second ago. A similar outcome features in Arthur C. Clarke's "The Light of Other Days". This aspect of the device is almost a "plot killer", because of the profound effects it has. It becomes impossible to use it as a "normal" feature of a society which we can understand.
At least one story attempts to set up a murder in a society where time-viewing makes it virtually impossible to commit one and escape punishment. The protagonist instead sets up an elaborate deception where he appears to be mentally unstable in a situation where the victim cannot help but goad him into an act of senseless violence, the murder weapon being an ornamental letter opener whose presence between them is carefully orchestrated.
A hard to find novellete by T.L. Sherred, "E for Effort" details a time viewer built by a poor genius who cannot get people to take him seriously, so he uses it to create historical movies which he then shows in his decrepit theatre. He is discovered by a Hollywood producer, who is able to exploit the viewer to create first movies, then historical reconstructions, and finally political documentaries. The last part is his undoing, as he exposes every crime committed in the name of patriotism and ideology by world leaders, resulting in the collapse of government and nuclear war.
Stories featuring Time Viewers
With Time Travel
- By His Bootstraps by Robert A. Heinlein.
- Millennium by John Varley.
- The End of Eternity by Isaac Asimov.