Ben McKenzie

Theses are the show notes and errata for episode 31, “It’s Just a Step to the West“, featuring guest Joel Martin, discussing the 2012 Long Earth novel The Long Earth.

• The episode title is a play on “It’s just a jump to the left”, the first instruction from dance anthem The Time Warp from the musical The Rocky Horror Show. It follows a young couple who are on their way to visit their old science lecturer to tell him they’re engaged, but on the way – actually, no, we can’t explain it. It makes no sense. You just have to experience for yourself.
• “Hard” science fiction is science fiction that attempts to be scientifically accurate, or at least scientifically plausible. Notable authors in this style include Jules Verne, Arthur C. Clarke, Poul Anderson, Larry Niven, Robert Heinlein, Kim Stanley Robinson, Neal Stephenson and Stephen Baxter. (Yes, it’s a bit of a boy’s club; please let us know your favourite hard sci-fi authors of other genders!)
• Joel previously appeared on episode 14, “City-State Lampoon’s Disc-Wide Vacation“, discussing The Colour of Magic on the 35th anniversary of its publication. We still hope to have him back for our episode covering The Light Fantastic on its 35th anniversary in June 2021.
• Stephen Baxter is an English science fiction author with degrees in Engineering and Mathematics who has written nearly sixty novels, giving Terry a run for his money! His most famous book is probably the award-winning 1995 novel The Time Ships, an official sequel to H. G. Wells’ The Time Machine. His Xelee series encompasses thirteen books, beginning with Raft, a novel that evolved out of the short story Joel mentions here. (Not to be confused with the Steven King short story “The Raft”, which is…very different.)
• Indiana Jones and the Kingdom of the Crystal Skull is, unfortunately, the very real fourth film in the Indiana Jones franchise. Released in 2008, and directed by Steven Spielberg, its set in 1957 and stars Harrison Ford as whip-cracking, two-fisted adventure archaeologist Indiana Jones, who alongside old flame Marion (Karen Allen) and her son Mutt (Shia LaBeouf) battles Soviet agent Cate Blanchett for control of an alien crystal skull which can unlock psychic powers. You can probably see why we weren’t into it. A fifth Indiana Jones film is in pre-production and scheduled for release in 2022.
• 1917 is a 2019 World War I film directed by Sam Mendes, and made to look like it happens in two long, continuous shots. It follows two young British soldiers sent across France to deliver orders calling off a doomed offensive.
• Mink Car is the eighth studio album by American alternative rock band They Might Be Giants, released on September 11, 2001. Pratchett appears to have been a fan of the band, as references to their work appear in a few of his books, including the spoof band “We’re Definitely Dwarves” in Soul Music.
• The mulefa are peaceful intelligent creatures from a parallel Earth featured in The Amber Spyglass, the third book in the original His Dark Materials trilogy by Philip Pullman. They have a superficial resemblance to elephants, but have a diamond-shaped skeleton with no spine, and a sophisticated culture, language and tools – including the use of special seed pods as wheels.
• Jasper Fforde is an English author best known for his novels about Thursday Next, beginning with 2001’s The Eyre Affair. Next is a “literary detective” from a not-entirely-serious parallel world, and her investigations sometimes take her inside great works of fiction. She is from her reality’s version of 1985, and many of Fforde’s books are set in worlds which feel like the recent past.
• As one of Liz’s faves, we’ve mentioned English author Diana Wynne Jones many times in previous episodes. Her works include the Chrestomanci series, Howl’s Moving Castle and its sequels, and The Tough Guide to Fantasyland. Jones has been cited as an inspiration by many British writers, including Pratchett.
• The term Datum Earth refers to the concept of a datum reference (or just datum) – an important part of an object nominated as a reference point for measurements. Hence the Datum Earth is the reference point for all travel East and West. The concept of datums – and yes, that’s the correct plural in this sense – sees use in many disciplines, including charting, mapping, engineering and many crafts. Big thanks to listener Nathan J. Phillips for explaining this one over Twitter!
• The North American Discworld Convention is a bi-annual convention which began in 2009, running opposite the UK convention which operates bi-annually in even years. The convention moves around the US; in 2011 it was held in Madison, Wisconsin, hence that city’s prominence in The Long Earth, while the 2019 convention was held in Los Angeles, with a theme of “Hooray for Holy Wood”. (We were very kindly invited, but unable to attend – maybe in 2021!) You can find out more at the official web site, nadwcon.com.
• We have mentioned the film Stargate and its television successor, Stargate SG-1, many times. Both follow an archaeologist and military commander who travel through a “stargate”, an ancient alien device that allows near-instantaneous travel to other worlds with stargates across the galaxy. The television series has often made a plot point out of the possibility of knowledge of the stargate – and the US military’s stargate programme – becoming public.
• Prometheus is Ridley Scott’s 2012 film set in the Alien universe, a prequel in which humans discover an extinct alien civilisation on a distant planet. Oh, and some horrible monsters, of course. It features Michael Fassbender as android David 8 (more on him below) and Noomi Rapace as archaeologist Elizabeth Shaw. It’s not good; maybe archaeologists and aliens just don’t mix?
• Jules Verne (1828 – 1905) was a French science fiction writer in the 19th century whose books were adventures based on scientific ideas. His most famous books are Voyage au centre de la Terre (Journey to the Centre of the Earth), Vingt Mille Lieues sous les mers (20,000 Leagues Under the Sea) and Le Tour du monde en quatre-vingts jours (Around the World in Eighty Days), all of which involve fantastic journeys either to extraordinary places or via extraordinary means. Maître du monde, or Master of the World, was his penultimate novel, published a year before his death. It’s a sequel to the earlier book Robur-le-Conquérant (Robur the Conquerer), and serves as a warning of totalitarianism. In the novel, science tyrant Robur uses his mastery of technology to create an extraordinary craft that can travel on land, sea and through the air so fast it is invisible, and uses it to terrorise the United States.
• Stonehenge is the most famous monument consisting of standing stones, first constructed around 5,000 years ago for purposes which remain mysterious. It’s in Wiltshire, the part of England in which Terry and his family lived much of their lives. The Singing Stones are an invention for the book, but there are stones that resonate when struck in much the same way. These “lithophones” occur naturally, like the “ringing rocks” found in Pennsylvania and New South Wales, and can be made into instruments called lithophones. A famous example are the Musical Stones of Skiddaw, constructed in the 18th century and now on display at the Keswick Museum and Art Gallery in northern England.
• Neal Stephenson is an American speculative fiction author who has written sixteen novels, the most famous probably Snow Crash (1992). Stephenson mixes themes of history, technology, religion and politics with a wry sense of humour – the main character in Snow Crash is named “Hiro Protagonist” – and the comparison to the combined Pratchett/Baxter style is apt. As well as books set in not too distant cyberpunk-ish futures, he has also written historical novels, but most also involve themes of technology and computers.
• “The High Meggas” was written in 1986, but not actually published until 2012, when it was included in Pratchett’s 2012 collection of short fiction, A Blink of the Screen – the same year as The Long Earth! In the short story, reclusive stepper Larry Linsay is minding his own business on an Earth in the High Meggas, avoiding the local “super baboons” and their leader, which he calls Big Yin. He detects the arrive of two security guards from the “gumment”: Joshua Valienté and Anna Shea. He captures them both, and each claims the other poisoned the water supply at Forward Base, the nearest government facility, killing fifty people. He has to decide who to trust, while still pondering the mysteries of the High Meggas… The term “High Meggers” (note different spelling) appears in chapter two of the novel with the same meaning as in the original short story: those earths more than a million steps away from Earth (not just in the high thousands, as Ben mentions). Both the story and chapter two of the book also use the term “Low Earths” to describe worlds only a few steps away from the original. The terms “Datum Earth”, “Long Earth” and even “step” do not appear in the original story, which uses “move” to describe the act of stepping – a term echoed in The Long Earth when Joshua refers to a “Knight’s Move”.
• The names Joshua and Jesus are close to each other in both English and the original Hebrew. In Hebrew, ישוע or “Yeshua” was a common alternative form of יְהוֹשֻׁעַ (“Yehoshua”). While they’re distinct in the source, Greek texts translate them both as Iesous (Ἰησοῦς), which became the Latin Iesus, and then in English, Jesus. In Greek Bibles Joshua is thus also named Jesus, though he is referred to as “Jesus, son of Naue” to differentiate him from Jesus, son of God. There are some English Bibles in which Joshua is referred to as Jesus, as well. The confusion doesn’t usually go back the same way, and some ancient texts seem to make it clear that Jesus only ever used the shorter version of the name, though it’s worth pointing out that Jesus was a pretty common name back then.
• We’ve not been able to find any record of gunmetal covered Bibles being used during the First World War, but there are certainly plenty of stories of Bibles in pockets stopping bullets – most of them probably apocryphal. The stories had an effect, though; metal-covered “heart shield Bibles” were common artefacts carried by American soldiers during World War II.
• The Biblical Joshua (aka Hoshea, Jehoshua or Jesus; see the note above) was Moses’ assistant, as documented in the Books of Exodus and Numbers in the Torah and Old Testament. He was born in Egypt before the exodus, and was present for many of Moses’ famous deeds. Later he spied on Canaan for Moses and after Moses’ death was chosen by God to lead the Israelites, and blessed with invincibility. He led the conquest of Canaan and lived a long life, dying aged 110. His later life is chronicled in the Book of Joshua.
• The toaster episode of The Simpsons is Treehouse of Terror V from the show’s sixth season in 1994, one of the annual Halloween anthologies. In the second segment, “Time and Punishment”, Homer accidentally turns a broken toaster into a time machine and travels to the past, altering history multiple times. As well as the no donuts world, he also creates a dystopia ruled by a despotic Ned Flanders.
• In the fourth Harry Potter novel, Harry Potter and the Goblet of Fire, the Quidditch World Cup stadium is hidden from non-wizards through the use of a “Muggle-Repelling Charm“. Muggles who came too near would suddenly remember an appointment for which they were late and hurry away.
• Celtic mythology is the source of most modern ideas of “the fae” in Western cultures, and belief in the “fair folk” (who go by many epithets) is still common in Ireland, as briefly discussed in episode 15 (and further in an outtake featured in episode three of our subscribers-only bonus podcast, Ook Club). The Otherworld as a concept is older and broader, and present in many religions and belief systems, but the Celtic version – known as Tír na nÓg, Annwn or Avalon in various traditions – matches up pretty well with the way the Trolls and Elves of the Long Earth use stepping to occasionally visit Datum Earth.
• In August 2019, an American musician tweeted about the need to ban assault weapons; in response, another Twitter used asked “How do I kill the 30-50 feral hogs that run into my yard within 3-5 mins while my small kids play?” The hypothetical was widely mocked and quickly became a widespread meme, though it didn’t last long. It resurfaced briefly in September that year after a news report of feral hogs in Canada potentially crossing the border into Montana. It’s worth noting that feral hogs – or feral pigs as we call them in Australia – are definitely real and can be quite destructive to wildlife, especially in countries like the US and Australia where they are not a native species. While they are indeed dangerous, attacks are rare.
• In X-Men comics, Nightcrawler is the alias of the German mutant, circus performer and superhero, Kurt Wagner. His mutation gives him a demonic appearance, with blue skin, red eyes, a prehensile tail, pointed ears and three-fingered hands and two-toed feet. He also has the ability to teleport short distances, disappearing and reappearing in a puff of smoke, with the smell of brimstone. He first appeared in 1975, and has featured in many adaptations of the comics. Nightcrawler is a major character in the 2003 feature film X2, where he is played by Scottish actor Alan Cumming. In the opening scene he attempts to kill the American President, leaping and teleporting to avoid the President’s security. He is often depicted fighting in the same way in various X-Men videogames.
• Sliders is an American science fiction series that ran for five seasons from 1995 to 2000. It starred Jerry O’Connell as Quinn Mallory, a genius physics student who invents a device that creates temporary wormholes into parallel universes. He accidentally traps himself and three others – his physics professor (John Rhys-Davies), his friend Wade (Sabrina Lloyd) and passing soul singer Rembrandt Brown (Cleavant Derricks) – on the other side of a wormhole. Each episode Quinn’s “timer” randomly resets, counting down the time until a new wormhole opens to another alternate reality. The episode Ben describes about a population controlled alternate Earth is “Luck of the Draw”, the first season finale. While there are no Trolls or Elves, Sliders does have the Kromaggs, an intelligent species of apes from a parallel Earth who can also travel between universes, stripping other versions of Earth for resources. (Ben recommends the first two seasons, but it gets a bit rocky after that, with three of the four main cast leaving )
• The Gap is an American clothing company founded in 1969. It grew to prominence in the 1990s, and now has thousands of stores in more than forty countries. The company owns several famous clothing brands, including Banana Republic and Old Navy. It has been involved in controversy over conditions in its factories and those of its suppliers in Saipan, Jordan and India.
• Stephen Baxter’s Xeelee Sequence spans nine novels and more than fifty short stories. It touches on many hard sci-fi ideas drawing on quantum physics, and follows humanity’s expansion into the wider universe and their conflict with the Xeelee, an ancient species of aliens in the “so technologically advanced they are almost gods” mould.
• The song “Step in Time” was written by the Sherman Brothers for the Walt Disney’s 1964 feature film adaptation of Mary Poppins. It’s sung by Mary’s friend Bert (American actor Dick Van Dyke, doing an infamously dodgy Cockney accent) and his fellow chimney sweeps as they dance on the rooftops of London. It’s a lot like “Knees Up Mother Brown”, with each verse identical except for a different repeated dance instruction, like “Kick your knees up”, “Flap like a birdie” and “Link your elbows”. (Later verses change these up for other phrases – including “Votes for women”!) In the 2004 Broadway musical, the song is introduced with the idea that chimney sweeps are like guardian angels who “step in, just in time” when someone is in trouble.
• A potato battery is created by sticking a piece of zinc and a piece of copper into a potato and connecting their exposed ends to an electrical circuit. The acidic potato juice reacts with the metals, resulting in a build up of free electrons in the zinc, and a loss of electrons from the copper. This creates an imbalance in electrical charge, causing electrons to travel from the zinc through the electrical circuit to the copper, producing an electrical current of about 0.5 Volts. (Lemons, the more popular vegetable battery choice, generate a higher voltage because they have more acidic juice.)
• In the 2007 videogame Portal, the player character, Chell, is forced to navigate a series of “test chambers” that can only be escaped through the use of a “portal gun”, which creates pairs of portals that link two locations. The test facility is run by a sinister artificial intelligence named GlaDOS. In the sequel, 2011’s Portal 2, GlaDOS is deposed by another AI and has her “personality core” attached to a potato battery, forcing her to team up with Chell. Neither of them is happy about it.
• Most laptops do contain metallic iron, since most of them still use magnetic hard drives. This form of storage, while susceptible to damage from physical knocks, is still a lot cheaper than hardier solid-state technology, so many laptops – especially ones with large storage capacities – still use it. Modern magnetic drives use iron and cobalt layered over aluminium, but a solid state drive largely depends on silicon, so it wouldn’t be too hard to make laptops that could travel between Earths.
• British glam rock star David Bowie appears on the cover of his 1973 album Aladdin Sane in character as Aladdin Sane, with a stylised red and blue lightning bolt painted across his face.
• Michael Fassbender plays two android characters – David 8 and Walter – in the films Prometheus and Alien: Covenant. Like the androids in the earlier films – particularly Ian Holm’s Ash in Alien, and Lance Henrikson’s Bishop in Aliens and Alien 3 – he is portrayed as an advanced synthetic organism, rather than a metal robot.
• We discussed Thomas and Will Riker, the transporter twins from Star Trek: The Next Generation, in our previous episode, “Looking Widdershins“. See that episode’s show notes for an explanation.
• In the X-Men comics and adaptations, mutants like Nightcrawler are humans who possess a specific genetic mutation, known as the X-gene, which causes them to develop superpowers, usually around puberty. Despite the prevalence of superheroes in the Marvel universe, mutants as a group are subject to mistrust, prejudice and bigotry. Their stories have served as allegories for the struggles of queer folks, people of colour and other marginalised communities. Anti-mutant sentiment is often shown to be political or religious in origin, or at least justified that way. There are many examples of charismatic leaders stirring up hatred against mutants for their own ends, including the Reverend William Stryker in the 1982 graphic novel God Loves, Man Kills, and recurring character Senator Robert Kelly, both of whom appear in the film adaptations.
• For any younger listeners, September 11 refers to the terrorist attacks on September 11, 2001, in which members of the group Al-Quaida highjacked four passenger aircraft and flew two of them into the twin towers of the World Trade Centre in New York, killing nearly 3,000 people.
• A “pilot episode” is the initial episode produced of a television series, especially in the United States, where pilots are ordered by networks to determine if a series will be produced. As a result they are often double the normal length and spend as much time setting up the characters and premise of the show as exploring any particular plot. Many pilots are re-shot after a series has been given the green light to produce more episodes, or are repurposed as flashback material or a later episode.
• The 1999 film Galaxy Quest, directed by Dean Parisot, is about the cast of a 1980s sci-fi show, Galaxy Quest, who now spend most of their time attending conventions. They are contacted for help by the alien Thermians, who believe the TV show was a documentary. The all-star cast includes Tim Allen, Sigourney Weaver, Alan Rickman, Sam Rockwell, Enrico Colantoni, Tony Shalhoub and Justin Long. It’s a loving parody of science fiction television and its fans, but with a heavy emphasis on the “loving”. It’s lasting popularity, especially among Star Trek fans, led to the production of Never Surrender: A Galaxy Quest Documentary, released for the film’s twentieth anniversary in 2019.
• In the world of Harry Potter, a squib is the child of magical parents who is not magical themselves – or at least, not able to do magic, for example the casting of spells. The canonical example is Hogwarts caretaker Argus Filch. We’ve previously talked about squibs, including way back in episode 2, “Murdering a Curry“.
• Stephen Baxter’s The Massacre of Mankind is not the first sequel to The War of the Worlds, but it is the only official one, authorised by the Wells estate. Baxter – who also wrote an official sequel to The Time Machine, The Time Ships – is a vice president of the H. G. Wells Society, a position he has held since 2006. The book is set in 1920 – 13 years after the events of the original book – and follows Julie Elphinstone’s journey through a second Martian invasion. Like many sequels it is also an alternate history, showing how the original invasion changed Europe and the rest of the world.
• Baxter collaborated with Arthur C. Clarke on the Time Odyssey trilogy, which is related to Clarke’s Space Odyssey series (Clarke coined the term “orthequel” for them, which is…unhelpful). They deal with a species of godlike aliens who – in an opposite move to Space Odyssey’s monolith building aliens – seek to remove other intelligent species, but wish to preserve a record of their cultures in an alternate universe. Baxter also wrote the 2000 novel The Light of Other Days, based on a synopsis by Clarke, which explores the consequences of technology allowing instantaneous viewing of events from anywhere in space and time.
• We discussed Good Omens, Pratchett’s collaboration with Neil Gaiman, in episode 15, “It’s the End of the World as We Know It (and We Feel Nice and Accurate)“. Both Pratchett and Gaiman acknowledged that Pratchett was the dominant voice in that book, not least because Gaiman was not an experienced novelist at the time and was busy making the release schedule for his hit comic Sandman. Despite that, elements of Gaiman’s style, and his influence on the plot, are definitely noticeable.
• The short story version of Raft, which Baxter expanded into the first novel of the Xeelee Sequence, was first published in the magazine Interzone in 1989. Finding out if it’s been collected anywhere has proven difficult, but you can find it online here, thanks to UK sci-fi ebook publishers infinity plus. You can also find a lot of short works by Baxter on his official web site, including many excerpts from and additions to the Long Earth series (most of them from later in the series, so beware of spoilers). We’ll add some more recommendations for works by Baxter here when we get them.
• We also mentioned the Moa in episode 29, “Great Rimward Land“. It was a large flightless bird native to New Zealand, now extinct. They were not carnivorous but could certainly kill a human being.
• Logan Paul is an American YouTube star, actor, podcaster and boxer. He became infamous in 2018 after visiting Aokigahara forest near Mount Fuji in Japan and posting footage of a man who had died by suicide there on his YouTube channel. While this was his worst stunt, he has done a lot of other awful stuff, including being cruel to animals, making disparaging remarks about homosexuality, and participating in dangerous trending fads. He was suspended by YouTube for a “pattern of behaviour”, though he claims brain damage sustained playing high school football has impaired his ability to have empathy for others. He’s also a Flat Earther.
• Depending on who you ask there are between four and five thousand varieties of potato. Let that sink in for a second. If you want to find out more, a great place to start is the European Cultivated Potato Database, maintained by SASA, a division of the Scottish Agriculture and Rural Delivery Directorate. The database very happily has all kinds of data, including “Utilisation Characteristics”; Ben’s favourites are “Crisp suitability” and “French fry suitability” (covering both possible meanings of “chips”).
• We’ve mentioned the Chrestomanci series by Diana Wynne Jones before, in episode 22, “The Cat in the Prat“. It consists of six novels and one collection of four novellas, all published between 1977 and 2006. In the books, the “Chrestomanci” is an enchanter – a powerful magician – employed by the government of World 12B to police the user of magic. The current Chrestomanci in nearly all the books is Christopher Chant.
• In Verne’s Hector Servadac (Off on a Comet), first published in 1877, 36 humans are swept away on the surface of comet that briefly collides with Earth near Gibraltar. The title character, a Captain in the French Algerian army, must contend with the English and Spanish solders and other people with whom he is marooned, while experiencing many strange phenomena on a two year orbit away from and then back towards Earth. The original has an anti-Semitic tone concerning one character which drew criticism even at the time, leading to low sales by Verne’s standards. Ben first experienced the story via the Australian animated adaptation made in 1979, which leaves out the offending character. (It’s here on YouTube, though with subtitles and misattributed to a 1976 US cartoon series.)
• There are twelve “series” of alternate worlds in the Chrestomanci series, each one a collection of worlds which are all similar to each other. Christopher Chant is from world 12A, where magic is common; world 12B is the “real world”, i.e. where we live. The worlds were first explored and numbered by the “Great Mages” who live on the worlds of series one.
• In the 2001 film The One, directed by James Wong, Jet Li plays Gabriel Yulaw, an agent of the MultiVerse Authority, who goes rogue and starts killing the alternate versions of himself in other universes, as this makes the remaining versions stronger. Li also plays Gabe Law, the las remaining alternate of Gabriel, who is a police officer in Los Angeles on our world. It’s a cool concept but critics pretty universally panned the film.
• In Diana Wynne Jones’ The Homeward Bounders, demonic entities known only as Them play boardgames with the many alternate universes – not unlike the gods of Dunmanifestin. When twelve-year-old Jamie discovers a group of them playing with his world, they make him a “Homeward Bounder” – forced to “bound” between the worlds, unable to influence Their game, but also virtually unaging and immortal as he searches for his home universe.
• “Dr Tuesday Lobsang Rampa“, aka Cyril Henry Hoskin, wrote and published The Third Eye in 1956. In it he claimed to have awakened his powers of clairvoyance through “the third eye” ritual, in which fellow Lamas drilled a hole in his forehead and implanted a sliver of wood “treated by fire and herbs” in his brain. Afterwards, one of the Lamas told him that for the rest of your life he would “see people as they are and not as they pretend to be”. When Hoskin was uncovered as a potential fraud by private investigators working for a Tibetologist, he did not deny his origins, but claimed that his body was now inhabited by Lobsang Rama. The story only gets weirder and we recommend you read up on it.
• Susan Calvin is a brilliant but emotionless “robopsychologist” who features in a dozen of Isaac Asimov’s short stories about robots. Marvin, the “Paranoid Android”, is a genius robot with a “genuine people personality” that means he is always depressed; he appears in Douglas Adams’ The Hitchhiker’s Guide to the Galaxy in all its incarnations. We discussed the horse from The Dark Side of the Sun in episode 18, “Sundog Gazillionaire“.
• Jeph Jacques’ Questionable Content is a web comic launched in 2003. It’s set in Northampton, Massatuchetts, in either a near future or alternate reality setting, and revolves around the day to day life of indie rock fan Marten Reed and his extended circle of friends, who include several artificial intelligences with robotic bodies. In 2019 it passed 4,000 strips and is still going, with instalments released three times a week. Liz and Ben are fans.
• Jack&Ian is the compound name for biologist Jack Cohen and mathematician Ian Stewart, co-authors of the four Science of Discworld books, as well as What Would a Martian Look Like? and several other fiction and non-fiction books. Jack passed away in 2019.
• The Kardashev scale, created by Russian astronomer Nikolai Kardashev in 1964, is a way of classifying intelligent civilisations based on the amount of energy they are able to use. Type I civilisations harness the energy naturally available on their own planet (as humans currently do); Type II civilisations harness all the power available from their home star; and Type III civilisations harness the power output of an entire galaxy. Extensions to the scale have since added Type IV (the power of an entire universe) and Type V (the power of multiple universes).
• Andre Norton was an American speculative fiction writer, and the first woman to hold many of science fiction’s highest honours. Her novels The Crossroads of Time (1956) and Star Gate (1958) are among the earliest alternate worlds stories to reference the many-worlds interpretation of quantum physics, and blend science ficiton with sword and sorcery.
• InterWorld is a 2007 standalone novel written by Neil Gaiman and Michael Reaves, in which high school student Joey discovers he is a Walker, one of a number of people who can step between alternate realities, and is recruited by InterWorld, an organisation working to keep the forces of magic and science in balance.
• Nine Princes in Amber by American fantasy writer Roger Zelazny is the first in the Chronicles of Amber series. In the series, “Amber” is one of two true worlds; all others, including the regular Earth that we know, are merely shadows caused by the tensions between these two worlds. Nobles of those true worlds are able to gain the power to “walk through Shadow”, travelling to any permutation of reality they can imagine.
• Feels like a while since we referenced 99% Invisible! The episode “Ten Thousand Years” from December 2014 is one of Ben’s favourites, and discusses the difficulty of creating adequate warnings for nuclear waste, which might need to be understood many thousands of years in the future. Stick with it right to the end, it’s amazing.
• The Long Earth audiobook is narrated by English actor and comedian Michael Fenton Stevens, who also narrated the other books in the series, as well as the non-fiction parts of The Science of Discworld books, The Folklore of Discworld, and some of the stories in the collection A Blink of the Screen.