"The Dead Past" is a science fiction short story by American writer Isaac Asimov, first published in the April 1956 issue of Astounding Science Fiction. It was later collected in Earth Is Room Enough (1957) and The Best of Isaac Asimov (1973), and adapted into an episode of the science-fiction television series Out of the Unknown. Its pattern is that of dystopian fiction, but of a subtly nuanced flavor. It is considered by some people to be one of his best short stories. Plot summary Asimov extrapolates the twin trends towards centralization of academic research and scientific specialization, to portray a world in which state control of scientific research is overseen by a vast bureaucracy, and scholars are effectively forbidden from working outside their narrow field of specialization. Working innocently under these constraints is Arnold Potterley, a professor of ancient history. Potterley, an expert on ancient Carthage, wishes to gain access to the chronoscope, a device which allows direct observation of past events, to establish whether the Carthaginians really sacrificed children by fire. Pioneered by a neutrino physicist named Sterbinski many years before, the chronoscope is now exclusively controlled by the government. When the government bureaucracy, in the person of bureaucrat Thaddeus Araman, denies Potterley's request for chronoscope access, Potterley sets in motion a clandestine research project to build a chronoscope of his own. Two people assist his quest: a young physics researcher named Jonas Foster and the physicist's uncle, a professional (i.e., licensed by the government) science writer, Ralph Nimmo. As a result of this work, the team makes a series of discoveries. First, they learn that the government has been suppressing research into chronoscopy; nevertheless, Foster invents a way to construct a chronoscope that is much more compact and energy-efficient than that of its pioneer inventor. Though this discovery delights Potterley, Foster soon proves that no chronoscope can see more than about 120 years into the past. In any attempt to observe an earlier time, the inevitable noise totally drowns out the signal. The government's reports of chronoscope observations of earlier years are thus clear fabrications. Personality conflicts and clashes of motivation cause the team members to fall out with each other. Potterley and his wife both remain disturbed by the death of their baby daughter in a house fire many years earlier, and there is the suggestion that he is subconsciously trying to exonerate the Carthaginians of