Schrödinger's cat in popular culture
Schrödinger's cat is a thought experiment, usually described as a paradox, devised by Austrian physicist Erwin Schrödinger in 1935. It illustrates what he saw as the problem of the Copenhagen interpretation of quantum mechanics, applied to everyday objects. The thought experiment presents a cat that might be alive or dead, depending on an earlier random event. In the course of developing this experiment, he coined the term "Verschränkung" (entanglement). Literature. It was not long before science-fiction writers picked up this evocative concept, often using it in a humorous vein. Several have taken  the thought experiment a step further, pointing out extra complications that could arise should the experiment actually be performed. For example, in his 2001 novel "American Gods," Neil Gaiman has a character observe, "if they don't ever open the box to feed it, it'll eventually just be two different kinds of dead." Likewise, Terry Pratchett's 1992 "Lords and Ladies" adds the issue of a third possible state, in the case of Greebo, "Bloody Furious". (In Pratchett's 2001 novel "The Last Hero", Death attempts the experiment himself, but cannot understand the mechanics of it, wondering if  it implies that he will kill the cat just by looking at it.) In "Will Grayson, Will Grayson", by John Green and David Levithan, the Cat makes an appearance as an analogy for Will and Jane's relationship. Robert Anton Wilson wrote a trilogy of novels dealing with themes related to quantum mechanics, collectively known as the "Schrödinger's Cat Trilogy". Douglas Adams describes an attempt to enact the experiment in his 1987 novel "Dirk Gently's Holistic Detective Agency." By using clairvoyance to see inside the box, it was found that the cat was neither alive nor dead, but  missing, and Dirk's services were employed to recover it, Dirk deducing that the cat had simply grown tired of being subjected to the experiment and wandered off (although he admits later that he was using the experiment as an attempt to determine the mental state of his friend Richard Macduff, Richard's logical arguments about why the experiment was pointless confirmed that he was mentally stable). In Libba Bray's 2009 book "Going Bovine", three stoners argue whether the cat is alive or dead, or whether the person who opens the box creates the possibilities. There are constant references  to a band called Copenhagen Interpretation, who disappear into thin air in the middle of a benefit concert. In Adam Felber's comic first novel, "Schrödinger's Ball" (2006), Dr. Erwin Schrödinger is a character, and there is much exploration of quantum mechanics. In the short story "Schrödinger's Cat-Sitter" by F. Gwynplaine MacIntyre (published in "Analog" magazine, July/August 2001), a time-traveller named Smedley Faversham visits the past to interview Erwin Schrödinger but gets tricked into taking care of Schrödinger's wife's cat while she is away and Schrödinger is visiting Max Planck. In attempting to  take care of the cat, Faversham inadvertently locks it in a cabinet with a Geiger counter, a vial of acid, and a hammer, unintentionally enacting Schrödinger's thought experiment, but with results that remain as uncertain as in the original case. The title character (though not the main character) of Robert A. Heinlein's 1985 novel "The Cat Who Walks Through Walls," a kitten named Pixel, is of indeterminate existence, and as such, can turn up in places that are specifically sealed to outside access. When this ability is questioned, the answer is "He's Schrödinger's cat," leading to  the response, "Then Schrödinger had better come to get him." In Glynne MacLean's 2009 short story "Viennese Meow" Schrödinger's cat tells his version of the famous thought experiment. In the S.M. Stirling ""T2"" novel trilogy, John Connor mentally compares his, Skynet's technology and ultimately everyone's existence to the Schrödinger principle of entropy. In the "Hellsing" manga series by Kouta Hirano, one of the depicted Nazis is an artificial catboy named Schrödinger. He claims that he is everywhere and nowhere at the same time, which is similar to the cat being alive and dead at the same  time. It is also said that he can only exist as long as he is aware of himself. In the second anime adaption, he eventually allows himself to be absorbed by the vampire Alucard, which causes his awareness to be clouded. This then spreads to Alucard, who vanishes for thirty years. Alucard returns after destroying the millions of souls within himself, giving him access to all of Schrödinger's abilities. On a somewhat more serious level, Ian Stewart's 2001 novel "Flatterland" (a sequel to "Flatland") attempts to explain many concepts in modern mathematics and physics through the device of  having a young female Flatlander explore other parts of the "Mathiverse". Schrödinger's Cat is just one of the many strange Mathiverse denizens she and her guide meet; the cat is still uncertain whether it is alive or dead, long after it left the box. Her guide, the Space Hopper, reassures the Cat with a modern view of quantum decoherence. Ursula K. Le Guin wrote a story entitled "Schrödinger's Cat" in 1974 (reprinted in "The Compass Rose," published in 1982), which also deals with decoherence. Greg Egan's 1992 novel "Quarantine," billed as "a story of quantum catastrophe", features  an alternative solution to the paradox: in Egan's version of quantum mechanics, the wave function does "not" collapse naturally. Only certain living things—human beings among them—collapse the wave function of things they observe. Humans are therefore highly dangerous to other lifeforms which require the full diversity of uncollapsed wave functions to survive. In the 2003 novel "Vernon God Little" by DBC Pierre, the concept is discussed by the Vernon and Jesus characters. It is erroneously attributed by Jesus to the German philosopher Immanuel Kant. In the play "Schrödinger's Girlfriend", the future Nobel Prize winner finds himself  falling under the spell of cabaret singer and seductress Hansi Haas, who has already had her way with Einstein, Planck and Bohr. As he wrestles with his love and the problems of wave theory, Haas throws him over for Paul Dirac, revealing a truth that holds for both love and quantum physics: "if you never ask the question, the answer can still be yes." (Review of play at Playbill) "MacSchrödinger's Cat", a 2010 novel by James Conor O'Brien, is a multi-verse romp across the universes centring on Venice and involves a search for a missing scientific experiment concerning  a trans-dimensional cat, with Janis Joplin as God, and a panoply of caricatures of physics and physicists ranging from James Clerk Maxwell and Schrödinger to String Theory, the Big Bang and infinitely annoyed monkeys. Martha Grimes' 2010 mystery novel "The Black Cat," one of the Inspector Jury series, features a black cat named Schrödinger, who is always getting into or blamed for trouble. The 1997 novel "To Say Nothing of the Dog" by Connie Willis tells the tale of a man named Ned Henry who travels back in time from 2057 to 1888 to find and return a cat  named Princess Arjumand to her owner. In his journey back through time, Ned finds the cat packed away in a covered basket and alludes to the lifelessness of her as they travel down the Thames. It is later discovered that in 1888 the butler, Baine, attempted to drown Princess Arjumand by throwing the box she was in into the Thames, only to be rescued by Verity, another time traveler, and brought to 2057. Many descriptions of Princess Arjumand in this book point back to how she might or should have perished in the Thames but was now alive through an  action that occurred and its improbability, alluding specifically to the paradox created in the thought experiment that is created by Schrödinger's cat. "Before Watchmen: Nite Owl/Dr. Manhattan," a 2014 graphic novel written by J. Michael Straczynski with artwork by Adam Hughes, refers to Schrödinger's cat several times in discussing quantum mechanics and the many different paths that history might take. Animals other than cats. Fiction writers have confined other animals besides cats in such contraptions. Dan Simmons's novel "Endymion" begins with hero Raul Endymion sentenced to death by imprisonment in a "Schrödinger box". Kōsuke Fujishima's  manga series "Ah! My Goddess" featured a play on Schrödinger's Cat. During one storyline, a storage room was expanded to infinite proportions and the main characters encountered a Schrödinger's Whale, an extremely rare species with the ability to travel through space-time in a five-dimensional quantum state. The male lead in the series, Keiichi Morisato, befriends the whale and teaches it songs by a real-life musical group The Carpenters (in the original English translation, it was Matthew Sweet) - but their time spent together is short, for the whale must move on or risk its safety as  its wave function collapses. Because of this need to keep moving through quantum states, Schrödinger's Whales hardly ever meet, the reason they are so thin on the ground — but miraculously, Keiichi secured the future of the species by teaching it the songs. After discovering the whale had gone, he found out that it had learned Only Yesterday by itself ("Missing Time" in the translation) - this gave the whales a call that they could locate each other by.