Manheim Effect
The Manheim Effect, named after Dr. Paul Manheim, was a term coined by Lieutenant Commander Data aboard the USS Enterprise-D in 2364, to describe the unusual temporal distortions created by Manheim's experiments into time. Manheim had created the effect when he opened a "window" into another dimension on Vandor IV.
A collapse of the time continuum causes Jean-Luc Picard, William T. Riker and Data to encounter themselvesThe Effect consisted of a moment in time looping or of people seeing a preview or repeat of the near future or near past caused by simultaneity of events otherwise taking place at different points on the time continuum. When this happened, it was possible for the participants in the events to interact with each other across the events, as Data did when he shut down the window of time. The Effect was felt throughout a radius of a few thousand light years from Vandor, notably on the USS Lalo, Coltar IV, and the Ilecom system. It was stopped when the "window" was sealed by Data. (TNG: "We'll Always Have Paris")