The media franchise Star Trek has borrowed freely from the scientific world to provide storylines. Episodes are replete with references to tachyon beams, baryon sweeps, quantum fluctuations and event horizons. Many of the technologies "created" for the Star Trek universe were done so out of simple economic necessity—the transporter was created because the budget of the original series in the 1960s did not allow for expensive shots of spaceships landing on planets.
Outside observers have used both Star Trek's strengths and its weaknesses for educational purposes. Physicist Lawrence Krauss has written The Physics of Star Trek, a book which postulates what phenomena might make some Star Trek technology feasible, while detailing the blunders the show has made. He followed this book with a sequel, Beyond Star Trek, which applies the same approach as Independence Day, The X-Files and others. Astronomer Phil Plait takes a similar attitude in his "Bad Astronomy" website, a regular feature of which is reviews discussing the scientific mistakes in popular movies and TV shows. Software developer and hyperreality theorist Alan N. Shapiro has written Star Trek: Technologies of Disappearance, examining the physics and computer science of all major Star Trek technologies, as well as posing the sociological question of why exactly our culture is so interested in building these technologies.
In most Star Trek series, subspace communications are a means to establish nearly instantaneous contact with people and places that are light-years away. The physics of Star Trek describe infinite speed (expressed as Warp 10) as an impossibility; as such, even subspace communications which putatively travel at speeds over Warp 9.9 may take hours or weeks to reach certain destinations. Since subspace signals do not degrade with the square of the distance as do other methods of communication utilizing conventional bands of the electromagnetic spectrum (i.e. radio waves), signals sent from a great distance can be expected to reach their destination at a predictable time and with little relative degradation (barring any random subspace interference or spatial anomalies).