Time travel in the context of "Paranormal romance"

Science fiction (often shortened to sci-fi or abbreviated SF) is the genre of speculative fiction that imagines advanced and futuristic scientific or technological progress. The elements of science fiction have evolved over time: from space exploration, extraterrestrial life, time travel, and robotics; to parallel universes, dystopian societies, and biological manipulations; and, most lately, to information technology, transhumanism (and posthumanism), and environmental challenges. Science fiction often specifically explores human responses to the consequences of these types of projected or imagined scientific advances.

The precise definition of science fiction has long been disputed among authors, critics, scholars, and readers. It contains many subgenres, including hard science fiction, which emphasizes scientific accuracy, and soft science fiction, which focuses on social sciences. Other notable subgenres are cyberpunk, which explores the interface between technology and society; climate fiction, which addresses environmental issues; and space opera, which emphasizes pure adventure in a universe in which space travel is common.

Faster-than-light (superluminal or supercausal) travel and communication are the conjectural propagation of matter or information faster than the speed of light in vacuum (c). The special theory of relativity implies that only particles with zero rest mass (i.e., photons) may travel at the speed of light, and that nothing may travel faster.

Particles whose speed exceeds that of light (tachyons) have been hypothesized, but their existence would violate causality and would imply time travel. The scientific consensus is that they do not exist.

Herbert George Wells (21 September 1866 – 13 August 1946) was an English writer, prolific in many genres. He wrote more than forty novels and dozens of short stories. His non-fiction output included works of social commentary, politics, history, popular science, satire, biography, and autobiography. Wells is most known today for his groundbreaking science fiction novels; he has sometimes been called the "father of science fiction", a title that has also been given to Jules Verne and Hugo Gernsback.

In addition to his fame as a writer, he was prominent in his lifetime as a forward-looking, even prophetic social critic who devoted his literary talents to the development of a progressive vision on a global scale. As a futurist, he wrote a number of utopian works and foresaw the advent of aircraft, tanks, space travel, nuclear weapons, satellite television and something resembling the World Wide Web. His science fiction imagined time travel, alien invasion, invisibility, and biological engineering before these subjects were common in the genre. Brian Aldiss referred to Wells as the "Shakespeare of science fiction", while Charles Fort called him a "wild talent".

Science fiction (or sci-fi) is a film genre that uses speculative, science-based depictions of phenomena that are not fully accepted by mainstream science, such as extraterrestrial lifeforms, spacecraft, robots, cyborgs, mutants, interstellar travel, time travel, or other technologies. Science fiction films have often been used to focus on political or social issues, and to explore philosophical issues like the human condition.

The genre has existed since the early years of silent cinema, when Georges Méliès' A Trip to the Moon (1902) employed trick photography effects. The next major example (first in feature-length in the genre) was the film Metropolis (1927). From the 1930s to the 1950s, the genre consisted mainly of low-budget B movies. After Stanley Kubrick's landmark 2001: A Space Odyssey (1968), the science fiction film genre was taken more seriously. In the late 1970s, big-budget science fiction films filled with special effects became popular with audiences after the success of Star Wars (1977) and paved the way for the blockbuster hits of subsequent decades.

Suspended animation in fiction refers to the temporary cessation of life processes experienced by fictional characters, followed by their subsequent revival. This process is commonly employed as a plot device in science fiction narratives. It is frequently utilized to transport a character from the past to the future, a form of forward-only time travel, or to facilitate interstellar space travel, which necessitates an extended journey for months or years, referring to space travel in fiction. In addition to accomplishing the character's primary objective in the future, they often encounter the unfamiliarity of a new world, which may bear only faint resemblance to their previous surroundings. On occasion, a character is portrayed as possessing skills or abilities that have become lost to society during their period of suspension, enabling them to assume a heroic role in their new temporal setting.

Alternate history (also called alternative history, allohistory, althist, or simply A.H.) is a subgenre of speculative fiction in which one or more historical events have occurred but are resolved differently than in real history. As conjecture based upon historical fact, alternate history stories propose "what if?" scenarios about pivotal events in human history, and present outcomes very different from the historical record. Some alternate histories are considered a subgenre of science fiction, or historical fiction.

Since the 1950s, as a subgenre of science fiction, some alternative history stories have featured the tropes of time travel between histories, the psychic awareness of the existence of an alternative universe by the inhabitants of a given universe, and time travel that divides history into various timestreams.

Science fiction is a genre of speculative fiction that deals with imaginative, futuristic and scientific concepts. These concepts may include information technology and robotics, biological manipulations, space exploration, time travel, parallel universes, and extraterrestrial life. The genre often explores human responses to the consequences of projected or imagined scientific advances.

Science fiction is related to fantasy, horror, and superhero fiction, and it contains many subgenres. The genre's precise definition has long been disputed among authors, critics, scholars, and readers. Major subgenres include hard science fiction, which emphasizes scientific accuracy, and soft science fiction, which focuses on social sciences. Other notable subgenres are cyberpunk, which explores the interface between technology and society, climate fiction, which addresses environmental issues, and space opera, which emphasizes pure adventure in a universe in which space travel is common.