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Gateways, which serve as entry points that can allow people to reach areas that are different from their own, play critical roles in a variety of situations and contexts. For example, gateways are important plot devices in many science fiction works, where they often take the form of wormholes, which are openings that allow people to move from one point in space (or time) to another without actually having to physically cross the distance between those two points, in a manner similar to teleportation. The idea of wormholes originated from the fact some scientists once speculated that black holes could serve as instantaneous “bridges” to other locations in space. Although scientists now generally believe that humans will not be able to use wormholes to travel through space, that has not stopped science fiction writers from using this concept in their novels.
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