The Chronovisor

A device that allows the viewing of history, as it literally happened. This is a non-disruptive / non-destructive time-viewing technology that does not interact with frozen space-time, and so does not result in the creation of additional universes.

The Chronovisor was developed by lawful robots after they had developed Replicators, and using those technologies enabled them to eventually surround everything in every universe. Later, they were able to exert interruptive control over any process they chose to disrupt or modify, which led to the elimination of instances of time travel (except to the current moment of already existing universes).

See: The Vatican, Langley (CIA)