50 Fun Facts About Time Travel

Which author's 1895 novella popularised the idea of travelling through the years by mechanical means?

He coined the term 'time machine', and sends his Time Traveller to the year 802,701 to meet the Eloi and the Morlocks.

In H.G. Wells's The Time Machine, the Time Traveller journeys to which year?

Humanity has split into the childlike Eloi and the subterranean Morlocks, a jab at Victorian class divisions.

Samuel Madden's 1733 Memoirs of the Twentieth Century is a set of letters from which years?

British ambassadors of the future write back to diplomats of the past about politics and religion.

Enrique Gaspar's 1887 novel El Anacronópete may be the first story to feature what?

It beat Wells's Time Machine by eight years.

In Washington Irving's 1819 tale, what mechanism sends Rip Van Winkle into the future?

It is an early example of the 'time slip' device that Twain later used with a knock on the head.

In Mark Twain's A Connecticut Yankee in King Arthur's Court, how is Hank Morgan sent back to Camelot?

Twain was inspired by a dream of being a knight, badly inconvenienced by the weight of his armour.

In Slaughterhouse-Five, Billy Pilgrim is abducted by aliens from which planet?

They see in four dimensions and greet every death with 'So it goes'.

In Back to the Future, what speed must the DeLorean reach to travel through time?

Marty triggers it by accident fleeing the terrorists who shot Doc.

How much power does the DeLorean's flux capacitor need for time travel?

In 1955 the only source is a lightning bolt, so Doc wires up the clock tower.

In the first draft of Back to the Future, the time machine was attached to what instead of a car?

Marty was to climb inside and ride it into a Nevada atomic bomb test to harness the energy.

Which actor was originally cast as Marty McFly and replaced by Michael J. Fox after filming began?

Reshooting his scenes added $4 million to the budget; the film still became 1985's biggest hit.

In Back to the Future, Doc sets the destination to November 5, 1955. What happened that day?

Marty ends up there without plutonium and has to make sure his parents fall in love.

What does TARDIS stand for in Doctor Who?

The first story in 1963 used the singular 'Dimension'.

The Doctor's TARDIS is stuck in the shape of what obsolete British object?

The BBC now holds the trademark on the design, even though the Metropolitan Police created it.

In which year did Doctor Who first air on the BBC?

Guinness lists it as the longest-running science-fiction series in the world.

In The Terminator, the cyborg is sent back from which year to 1984?

Its mission is to kill Sarah Connor before her son can lead the resistance against Skynet.

James Cameron got the idea for The Terminator from what?

It struck during the release of his first film, Piranha II: The Spawning.

Terry Gilliam's 12 Monkeys is based on which 1962 French short film?

Chris Marker's short is told almost entirely in still photographs.

In 12 Monkeys, James Cole is sent back from which year, 29 years after the virus?

Brad Pitt earned an Oscar nomination and won a Golden Globe for the film.

In Bill & Ted's Excellent Adventure, what shape is the time machine?

Rufus brings it to San Dimas so the boys can pass their history report.

In Groundhog Day, Phil Connors relives which date over and over?

Filming took place in Woodstock, Illinois, not Punxsutawney.

In Hot Tub Time Machine, four men are sent back to which year?

It happens at the Kodiak Valley Ski Resort, where they had partied as youths.

In Somewhere in Time, Christopher Reeve's character travels to 1912 by what method?

He is yanked back to the present when he finds a penny minted in 1979 in his pocket.

In Outlander, nurse Claire Randall is transported from the 1940s to which era of Scottish history?

She passes through a stone circle at Craigh na Dun near Inverness and meets Jamie Fraser.

Octavia Butler's Kindred (1979) sends Dana from 1976 Los Angeles to a plantation in which state?

She is repeatedly pulled back to the early 19th century and must survive slavery to return home.

In The Time Traveler's Wife, Henry DeTamble's involuntary time travel is caused by what?

It is later named Chrono-Impairment; Audrey Niffenegger's 2003 debut became a film and an HBO series.

Shane Carruth's cult time-travel film Primer was made for roughly how much?

It won the Grand Jury Prize at Sundance in 2004 with a crew of five.

In Avengers: Endgame, the heroes reach the past through what?

Scott Lang's escape from it after five years gives them the idea for the 'time heist'.

Timecop stars Jean-Claude Van Damme as a policeman in 1994 who by 2004 works as what?

It was directed by Peter Hyams and based on a Dark Horse comic.

In physics, what are spacetime loops that would let an object return to its own past called?

Solutions of general relativity contain them, but their physical plausibility is uncertain.

Which logician's 1949 rotating-universe solution to Einstein's equations would allow travel to the past?

It made his friend Einstein doubt his own theory; the catch is that our universe does not seem to rotate.

The classic causality problem of killing an ancestor before you are conceived is known as what?

Novikov and Deutsch offered ways around it via self-consistency or interacting many-worlds.

The Novikov self-consistency principle gives what probability to any event that changes the past?

Larry Niven's 'law of conservation of history' is the science-fiction version of the same idea.

Stephen Hawking's suggestion that the laws of nature forbid time travel is called what?

He also proved you cannot build a certain kind of time machine with positive energy density everywhere.

Wormholes are also known as bridges named after which two physicists?

John Archibald Wheeler later gave them the catchier name.

Which physicist coined the term 'wormhole'?

He was inspired by Hermann Weyl's work; Kip Thorne later advised on Interstellar's wormhole.

In relativity's twin thought experiment, what happens to the sibling who travels at relativistic speed and returns?

Paul Langevin first laid it out in 1911; the acceleration at turnaround is what breaks the symmetry.

Thanks to time dilation, cosmonaut Sergei Krikalev is about how much younger than if he had stayed on Earth?

He spent 803 days in orbit, then the fourth-most of anyone.

Which real-world technology has to correct for relativistic time dilation to work?

Satellite clocks run at a different rate from clocks on the ground, and the offset is built into the system.

The Hafele-Keating experiment tested time dilation by doing what?

The airborne clocks disagreed with those left on the ground by exactly the predicted nanoseconds.

In Time Bandits, how many dwarfs spill out of young Kevin's wardrobe with a stolen map?

Randall leads Fidgit, Strutter, Og, Wally and Vermin; the Supreme Being wants his map back.

In the Hindu Vishnu Purana, King Kakudmi returns from visiting which god to find ages have passed?

The Japanese legend of Urashima Tarō tells a similar tale of a fisherman back from an undersea palace.

In the Talmud, Honi HaMe'agel sleeps for 70 years after watching a man plant what?

He wakes to find the man's grandson harvesting its fruit.

Which Japanese legend has a fisherman return after three days to find centuries gone?

He had been visiting an undersea palace.

Louis-Sébastien Mercier's 1770 dream-novel about a sleeper waking in the future was set in which year?

Edward Bellamy's Looking Backward (1888) and Wells's When the Sleeper Awakes (1899) used the same device.

In which newspaper did Edward Page Mitchell's 1881 story 'The Clock that Went Backward' appear?

It is among the first stories to use a machine for time travel, though the clock's workings are never explained.

Which physicist's 1974 analysis showed a dense, infinitely long spinning cylinder could allow travel to the past?

Van Stockum (1936) and Lanczos (1924) had found the solution without spotting the closed timelike curves.

What did a Baltimore group calling itself the Krononauts host in 1982?

MIT's Time Traveler Convention and Stephen Hawking's reception tried the same trick; nobody from the future showed up.

Which Australian city's 'Destination Day' advertised a permanent meeting place for future time travellers?

Such events can only ever prove time travel exists, never that it does not.

Which Buddhist Pāli Canon text has Kumara Kassapa explain that time flows differently in the heavens?

It sits alongside Hindu and Japanese legends as an ancient tale of leaping forward in time.