A space–time code (STC) is a method employed to improve the reliability of data transmission in wireless communication systems using multiple transmit antennas. STCs rely on transmitting multiple, redundant copies of a data stream to the receiver in the hope that at least some of them may survive the physical path between transmission and reception in a good enough state to allow reliable decoding.

Space time codes may be split into two main types:

STC may be further subdivided according to whether the receiver knows the channel impairments. In coherent STC, the receiver knows the channel impairments through training or some other form of estimation. These codes have been studied more widely because they are less complex than their non-coherent counterparts. In noncoherent STC the receiver does not know the channel impairments but knows the statistics of the channel. In differential space–time codes neither the channel nor the statistics of the channel are available.

A timecode (alternatively, time code) is a sequence of numeric codes generated at regular intervals by a timing system.

In video production and filmmaking, SMPTE timecode is used extensively for synchronization, and for logging and identifying material in recorded media. During filmmaking or video production shoot, the camera assistant will typically log the start and end timecodes of shots, and the data generated will be sent on to the editorial department for use in referencing those shots. This shot-logging process was traditionally done by hand using pen and paper, but is now typically done using shot-logging software running on a laptop computer that is connected to the time code generator or the camera itself.

The SMPTE family of timecodes are almost universally used in film, video and audio production, and can be encoded in many different formats, including:

Keykode, while not a timecode, is used to identify specific film frames in film post-production that uses physical film stock. Keykode data is normally used in conjunction with SMPTE time code.

In physics, spacetime (or space-time, space time, space-time continuum) is any mathematical model that combines space and time into a single continuum. Spacetime is usually interpreted with space as being three-dimensional and time playing the role of a fourth dimension that is of a different sort from the spatial dimensions. From a Euclidean space perspective, the universe has three dimensions of space and one dimension of time. By combining space and time into a single manifold, physicists have significantly simplified a large number of physical theories, as well as described in a more uniform way the workings of the universe at both the supergalactic and subatomic levels.

In non-relativistic classical mechanics, the use of Euclidean space instead of spacetime is appropriate, as time is treated as universal and constant, being independent of the state of motion of an observer. In relativistic contexts, time cannot be separated from the three dimensions of space, because the observed rate at which time passes for an object depends on the object's velocity relative to the observer and also on the strength of gravitational fields, which can slow the passage of time.

Charles "Chuck" Missler is an author, evangelical Christian, Bible teacher, former businessman and US Naval officer. He is the founder of the Koinonia House ministry based in Coeur d'Alene, Idaho.

Missler was for several years the chairman, the chief executive, and the largest shareholder of Western Digital. In 1983 he became the chairman and chief executive of Helionetics Inc., another technology company. After teaching for many years at Calvary Chapel Costa Mesa, Missler moved to Coeur d'Alene in 1992 and founded Koinonia House. Through this organization, Missler distributes a monthly newsletter, Bible study tapes, and a radio show, and speaks at conferences.

Missler is a prominent speaker on the subject of bible prophecy. Missler has had numerous programs aired on the Christian television station GOD TV, namely the DVD versions of his biblical studies "Learn the Bible in 24 Hours", "The Book of Revelation", "The Book of Genesis", and "The Book of Daniel".^{[citation needed]} A Los Angeles Times article reported that Missler and co-author Hal Lindsey had plagiarized a portion of Miami University Professor Edwin Yamauchi's 1982 book Foes From the Northern Frontier in their own 1992 book The Magog Factor. A YouTube video in which Missler uses a jar of peanut butter to attempt to disprove evolution attracted media attention in 2007-2008.

Ronald Lawrence Mallett (born March 3, 1945) is an American theoretical physicist, academic, and author. He has taught physics at the University of Connecticut since 1975. He is best known for his scientific position on the possibility of time travel.

Mallett was born in Roaring Spring, Pennsylvania, on March 30, 1945 and grew up in The Bronx in New York City, New York. When he was 10 years old, his father died at age 33 of a heart attack. Inspired by a Classics Illustrated comic book version of H.G. Wells' The Time Machine, Mallett resolved to travel back in time to save his father. This idea became a lifelong obsession. His brother is artist Keith Mallett.

In 1973 when he was 28 years old, Mallett received a Ph.D. from Penn State University. Also that year, he received the Graduate Assistant Award for Excellence in Teaching.

In 1975, Mallett was appointed a job as Assistant Professor at the University of Connecticut, where he continues to work today. His research interests include general relativity, quantum gravity, and time travel.