Line #32 Main/FirstContactMath


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6	->''"How about we just talk to them before we start throwing math problems at them?"''
7	-->-- '''Louise Banks''', ''Film/{{Arrival}}''
8
9	FirstContact situations with StarfishAliens have an inherent problem -- since the aliens are so incomprehensible, how will you even realize that they're intelligent? For that matter, how can you convince them that you are?
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11	The generally accepted universal signal of intelligence in this situation is the ability to produce a sequence of prime numbers: numbers that are only divisible by the number one and themselves. Why? Because it doesn't matter what number base you are using or what you call the numbers, 7 rocks cannot be divided up into any whole number of equal groups of rocks without breaking them. '''If''' the aliens have [[UsefulNotes/{{Mathematics}} math]], they'll get this -- resource allocation is one of the first tricks any group has to figure out. The idea is that they're too irregular to arise from any natural process[[note]]Although reproduction cycle periods of some insects tend to be a prime number of years to prevent matching another kind and then predators synchronising on them[[/note]] (i.e., no mathematical equation is known that will ''exhaustively'' produce them in reasonable time[[note]]There are equations that can produce an unlimited amount of prime numbers, but not all of them, and methods that will get them all, but the computation time is by brute force and thus enormous.[[/note]]), but mathematically simple enough that it's assumed any intelligent being can recognize them as non-random. More generally, anything obviously recognizable as simple math (such as digits of pi, or a proof of the Pythagorean theorem) can serve the same function. Of course, the digits of pi will change if the aliens don't have a base-10 system ([[AlternativeNumberSystem odds are that they don't]]), while the prime numbers will not change if you represent them properly.
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13
14	Often this can look like an instance of OnlySmartPeopleMayPass (just like plenty of humans do not know about prime numbers or basic math, plenty of otherwise intelligent aliens won't know what to do with the puzzle). However, while OnlySmartPeopleMayPass happens in the context of a pre-created puzzle or situation, the entire point of First Contact Math is that it provides the best hope we might have of communicating without having any context at all.
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16	See also FirstContactTeam, for when First Contact Math might fail and you need to plan for ''any'' contingency.
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18	----
19	!!Examples:
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21	[[foldercontrol]]
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23	[[folder:Comic Books]]
24	* ''[[http://en.wikipedia.org/wiki/Life_on_Another_Planet Life on Another Planet]]'' (1978) by Creator/WillEisner. An artificial radio signal from Barnard's Star listing prime numbers (although the term "prime" is never used in the story) is received at the Mesa Radio Astronomy Observatory.
25	* Averted in a [[ComicBook/DisneyMouseAndDuckComics Mickey Mouse]] comic: Mickey was kidnapped by aliens and treated as a [[HumanPet pet]]. When he wrote complex mathematics on the walls of the spaceship, it was dismissed as random scribbling. How he got the aliens to recognize him as an intelligent being? [[spoiler: Cooking.]]
26	* ''ComicBook/SupermanUnchained'': On the brink of World War II in 1938, US scientists sent a mathematical equation into space, but the mathematical equation was incorrect, and added up to more than the sum of its parts, to signify the message "let us add up to more, together." Eleven seconds later, The Wraith's ship crash landed on Earth, with a similar, more complex equation.
27	* ''ComicBook/UltimateFantasticFour'': When Reed makes contact with some residents of the Negative Zone, their first few exchanges are conducted in binary. After Reed sends them Pi and the human symbol for "hydrogen", their computer takes over and downloads the first contact package he prepared.
28	[[/folder]]
29
30	[[folder:Fan Works]]
31	* The basic story of ''Fanfic/Arrow18MissionLogs'' is of first contact between humans and ponies. After Twilight Sparkle leaves Randy (the human astronaut who just landed in Equestria) a basket with some food, he leaves a sheet of paper with basic math problems on them (including a chart indicating that "1" means one, "2" means two, etc.) Twilight's reaction when she figures out that the "stridetaur" is trying to communicate with math is one of [[{{Squee}} unbridled glee]].
32	* Discussed but ultimately averted in ''Fanfic/TheNextFrontier''. The odds of anything remotely recognisable as prime numbers or similar at interstellar distances are pretty much nil, but a single repeating tone or a noise like [[http://en.wikipedia.org/wiki/File:Radio_beacon_of_distress_on_121,5_MHz.ogg this]] could carry much further. [[spoiler: And by the time first contact actually happens, the aliens have LearntEnglishFromWatchingTelevision anyway.]]
33	* Notably averted in ''Fanfic/MassEffectClashOfCivilizations''. Both the [[Franchise/{{Halo}} UNSC]] and [[Franchise/MassEffect Citadel]] have their own method of deciphering language, neither of which involve mathematics.
34	* PlayedForLaughs in ''FanFic/SomeoneHasHeardThemScream''. When the SA ship first encounters the Council survey ship, they start by transmitting the prime number sequence. The Citadel ship crew recognizes the prime number sequence pretty quickly... and then gets sidetracked trying to guess what a sequence of numbers is supposed to convey.
35	--> So, what are they saying? That they are a race of mathematicians? That they only want to talk to mathematicians? That they need help with a math problem?
36	** After guessing that the prime numbers were a generic "I am intelligent and want to talk about intelligent things" signal, the Citadel ship responds by sending back all the ''non''-prime numbers in between the numbers the humans sent, to try and signal that they are willing to meet the humans halfway. The humans are, unsurprisingly, baffled.
37	* ''FanFic/TheMissionStaysTheSame'': When they leave Illium, the ''Normany'' crew picks up a Gyrinx, a large alien feline that communicates through {{Telepathy}} with other psykers. In order to prove its sapience to the Citadel Council and get FirstContact rolling, Mordin has the Gyrinx (named M'tarr) answer some basic math questions in a recording while [[SpaceElf Maeteris]] translates more complex language. Not only does M'tarr answer the questions correctly, she also displays several other signs of sapience that Mordin was watching for: emotions (flattening her ears in annoyance and asking through Maeteris if Mordin thinks she's stupid when he gives M'tarr a very basic question), creative thinking (answering his second question with a riddle), and understanding of astronomy (said riddle being an accurate calculation of the lunar cycle of M'tarr's homeworld Moarheff).
38	[[/folder]]
39
40	[[folder:Films -- Animation]]
41	* Queen Watevra Wa'Nabi in ''WesternAnimation/TheLegoMovie2TheSecondPart'' tells the gang she's going to talk to them in the universal language. Princess Unikitty guesses it's math, but it turns out to be song, [[MusicalNumberAnnoyance to Lucy's horror]].
42	[[/folder]]
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44	[[folder:Films -- Live-Action]]
45	* ''Film/{{Arrival}}'': One of the first things attempted for meaningful communication with the aliens. It doesn't work until they try sending extremely advanced mathematics rather than simple ones. Turns out the aliens' minds are structured very differently, so what is simple and easily understandable for humans is not so for them.
46	* ''Film/ColossusTheForbinProject'': How Colossus establishes a common language with the Soviet MasterComputer Guardian. It starts with 1+1=2 and in a few hours has developed an entire new language for them to communicate. Unfortunately this alarms both governments as they can't be sure strategic secrets aren't being leaked, so the President and Premier decide to break the link. [[NukeEm The computers do not react well]].
47	* ''Film/{{Contact}}'' has aliens contact Earth by sending a sequence of prime numbers. Later, they send instructions for building a machine to reach them by embedding basic universal math principles into the instructions so any race with knowledge of mathematics can decode it and build the machine.
48	* Attempted by Lob in the Soviet cult classic ''Film/MoscowCassiopeia'', when he encounters a pair of HumanAliens (actually, they're RidiculouslyHumanRobots, but he doesn't know that yet) on a planet seemingly devoid of intelligent life. Despite possessing a UniversalTranslator, he tries this trope by writing out the "(a + b)[[superscript:2]]" formula and turning it into "a[[superscript:2]] + 2ab + b". One of the aliens grabs his marker and adds the "[[superscript:2]]" to the last symbol.
49	[[/folder]]
50
51	[[folder:Literature]]
52	* In Creator/ArthurCClarke's novel version of ''Film/TwoThousandOneASpaceOdyssey'', Dave Bowman tries (unsuccessfully) to talk to the Iapetus monolith by broadcasting primes at it.
53	%% The monolith ratios in 2001 are not an example. The humans know the monoliths are artifacts because they're perfect rectangular prisms, not because they have any particular ratio; when Bowman understands the reason, it's heavily implied to be something inscrutable and alien, not because the monolith-builders were trying to make something that would demonstrate their intelligence.
54	* ''Literature/TheActionHerosHandbook'' has a chapter on communicating with extraterrestrials, and suggests starting with basic concepts like numbers and shapes because the authors of the book believe that no matter how alien the culture is, they would still be able to have dialogue about that, especially if they're able to go into space.
55	* The alien ship in ''Literature/{{Anathem}}'' has a proof of the Pythagorean Theorem on its hull for this reason.
56	* How the writings written on the Mecha were deciphered in "The Themis Files". With their own Base-8 system but the formulas were consistent with Earth's
57	* In ''The Andromeda Affair'', the aliens are transmitting a sequence of bits whose length is the product of two primes. The hero assumes correctly that this implies the bits should be arranged in a two-dimensional grid to be understood.
58	* Creator/IsaacAsimov:
59	** ''Literature/TheLeftHandOfTheElectron'': This NonFiction book describes the concept of "parity" in physics, and creates a FramingDevice where you are sending an interstellar radio message to an alien culture. How do you describe the concepts of "right" and "left"? Start with math.
60	** "Literature/NotFinal": Birnam describes how first contact with Jovians involved a lot of back-and-forth on math, such as adding, square roots, and factorials. This went on for over five years, as human scientists on Ganymede communicated by radio clicks to the surface of UsefulNotes/{{Jupiter}}.
61	* This fails in ''Calculating God'' by Creator/RobertJSawyer; transmissions to Delta Pavonis go unnoticed by the native Wreed, because the Wreed have a brain structure that makes them incapable of doing math. (They can automatically recognize numbers of up to 46, and that's it.) They are very good at ethical problems and analog simulations, though. The Forhilnor also admit that they were astonished to find a civilization on the Wreed homeworld, but stoutly defend their intelligence, noting that the Wreed build beautiful cities out of the sparse available materials there.
62	* In the French novel ''Ceux de nulle part'', the protagonist tries to communicate with an alien by using basic math and fails. Then again, [[EldritchAbomination normal physical laws do not seem to apply]] to said alien.
63	* ''Literature/ChildrenOfTime2015'':
64	** The human project to fill the galaxy with life involves terraforming planets, introducing monkeys infected with a virus that will [[UpliftedAnimal uplift]] them over generations, then putting a satellite in orbit to broadcast a radio message containing a simple mathematical sequence at the planet over and over again. The expectation is that, as the monkeys attain human-like intelligence, they will develop the means to detect the message and reply to it with the next steps of the sequence, signaling that they're ready to meet their makers. However, circumstances cause all but one world to suffer ecological collapse, and on that world, the monkeys never arrived. What arises instead is a sentient species of jumping spider, and [[AgainstMyReligion cultural]] and [[BizarreAlienPsychology psychological factors]] prevent them from responding to the message until centuries after they first detect it, and the interstellar human empire imploded thousands of years before that.
65	** In [[Literature/ChildrenOfRuin the sequel]], the ''Voyager'' attempts something similar with the new octupi species. All octupi communications involves an underlayer of mathematics, so the Humans and Portiids figure they can just respond in kind. As it turns out, the octupi are multi-brained creatures, and the logical brains that are sending the math are not the ones making the decisions. The linguist has to figure out how to interpret the ''far'' more confusing color-based emotional language to get her point across. She also notes that, despite what the mathematicians claim, all communication cannot actually be reduced to math.
66	* In "Literature/ColdSnap" by Creator/KimNewman, the villain has revived a dormant non-human intelligence that existed before all other life on Earth. While the hero is trying to figure out how the villain communicates with it, he goes through several of the standard options including numbers, but concludes that the creature is too alien even for those to be common ground. "A being on her scale has no use for any number other than 'one'."
67	* ''Literature/{{Contact}}'': The alien transmission begins with a sequence of prime numbers, before continuing on to more useful mathematics and science. The novel by Carl Sagan (who also championed the use of primes in this context in RealLife SETI) makes considerably more of this, also using prime numbers in the encoding of the more complex layers of the transmission.
68	* In James Cambias' ''A Darkling Sea'', when one of the Ilmataran tried to properly establish communication with a human on their planet (after the FirstContactFauxPas that cause conflicts between humans and Sholens over AlienNonInterferenceClause issue on contacting Ilmatarans), Rob, the main character, tried to tap 1+1=2 and 2+2=4 to see if the Ilmataran can realize that he's an intelligent being and try to start learning to communicate. It works. This is probably helped by the fact that non-echolocation-based component of Ilmataran language is based on math and mapping words to numbers.
69	* In ''Literature/{{Dreamcatcher}}'' by Creator/StephenKing, a population of infected send pleading messages interspersed with a recitation of prime numbers. One of the characters speculates it is to prove they're an intelligent species. They must not be that intelligent though, since they include 27 and 117 in their list. (Also 1, but that's somewhat reasonable, depending on how you define primes.) This deviation from the primes isn't noted in the novel though, and was probably either unintentional or done because the numbers have significance to Derry, the novel's setting.
70	* The RealLife attempts by SETI are described in ''Literature/EarthTheBook'' or, as Jon Stewart calls it, "drunk-dialing the universe".
71	* Used, then subverted in the series beginning with ''Emprise''. An alien transmission is recognized and eventually translated into a simple depiction of the aliens and their system. However, one mathematician claims to have found many more levels of meaning embedded in the message, à la ''The Bible Code''. Ultimately, it turns out that these new levels are the product of his overactive imagination. Double subverted in that the message turns out to be from [[spoiler:the remnants of a human colony from humanity's ''first'' attempt at interstellar colonization '''during the last ice age''', which came to an abrupt end when the ''real'' StarfishAliens wiped out (almost) all of the colonies and bombed Earth back into the stone age.]]
72	* In Creator/HGWells' ''Literature/TheFirstMenInTheMoon'', Cavor discusses using math to communicate with his alien captors, but he doesn't really have any idea how to do so.
73	* ''Literature/GiantsSeries'': In a related "First Contact Chemistry", in James P. Hogan's ''Inherit the Stars'', the key to deciphering an alien language comes when someone recognizes a Periodic Table of the Elements in an alien book.
74	* The Polish short story "Koła na piasku" by Adam Pietrasiewicz parodies this: a human and an alien talk to each other friendlily by radio before realizing what the other is. They immediately proceed to follow the "standard first contact procedures"; the human draws a Pythagorean triangle, while the alien draws some squiggly lines. They then go back to their vehicles and complain by radio that they can't comprehend what the other one drew (and none of them knows math very well, so they don't even know what they drew, only that they were told to draw them).
75	* In ''[[Literature/TheLongEarth The Long Utopia]]'', human scientists use this when trying to communicate with the silver beetle creatures. They are summarily ignored, and Lobsang admits that he'd probably just laugh if he saw some strange creature counting out basic numbers with rocks.
76	* In ''Literature/AMartianOdyssey'' by Stanley Weinbaum, the human explorer communicates with the Martian first with the words "one" and "two" demonstrated with rocks. The bird creature learns a few English words, at one point saying "No One One Two" to describe a creature that is unintelligent, and "One One Two Yes, Two Two Four No" for a creature of very rudimentary intelligence.
77	* Creator/LarryNiven and Jerry Pournelle's ''Literature/TheMoteInGodsEye'' has the human exploration party and the Moties use this method for initiating communications.
78	-->Cargill and Horvath's team worked together to answer the pulses. ''One, two, three, four'' blinked the light, and Cargill used the forward batteries to send ''five, six, seven''. Twenty minutes later the light sent ''three one eight four eleven'', repeated, and the ship's brain ground out: ''Pi, base twelve''. Cargill used the computer to find ''e'' to the same base and replied with that.\
79	But the true message was, ''We want to talk to you''. And ''[=MacArthur=]'''s answer was, ''Fine''.\
80	Elaborations would have to wait.
81	* ''Literature/ChanurNovels'': In ''The Pride of Chanur'', when the human Tully is cornered by the [[CatFolk felinoid Hani]], he writes out (in his own blood) numbers from zero on up. When he gets to 10, they realize that he might be using a [[http://en.wikipedia.org/wiki/Positional_notation positional notation system]].
82	* The ''Murderous Maths'' book discussing the properties of numbers discusses this trope.
83	* Referenced in ''Literature/NoughtsAndCrosses''. Callum and Sephy are discussing their favourite school subjects, and Sephy can't believe that Callum likes maths. Callum references the countless ways maths is essential, including this trope, in response.
84	* Creator/HBeamPiper's "Literature/{{Omnilingual}}": This {{novelette}} uses the Periodic Table as [[CommonTongue a universal key]]. It helps that the Martian language tends to make new words by combining existing ones, so that (for example) the word for "metal" is part of the names of various metallic elements.
85	* In ''Literature/SchildsLadder'' by Creator/GregEgan, the protagonists realize that there's intelligent life inside a pseudovacuum when they notice that a series of pulses coming from it represent consecutive prime numbers.
86	* The Creator/BarbaraHambly novel ''Literature/TheSiliconMage'' shows Antryg and Joanna communicating with an extra-dimensional via Pi and Planck's Constant.
87	* In Creator/MichaelCrichton's ''Literature/{{Sphere}}'' this is the way Harry manages to first make meaningful contact with the mysterious alien presence.
88	* ''Literature/TomSwift Jr.'' and his father communicate with some aliens by sending mathematical symbols at them (and vice versa) throughout his entire series. Exactly what is meant by "mathematical symbols" is never made particularly explicit.
89	* In ''Cauldron'', Literature/PriscillaHutchins realises that SpaceClouds they are observing have formed a GiantEyeOfDoom looking back at them. While everyone else freaks out, she tries flashing her navigation lights at the 'eye', and gets flashes of 'lightning' inside the cloud as a response. Eventually by using the lights to perform basic math, they're able to start rudimentary communication.
90	* In ''Literature/StarsReach'' by Creator/JohnMichaelGreer, both humanity and the Cetans tried this to find out whether there was other life in the universe. However, it took a while for both sides to realize they were receiving messages, because [[BizarreAlienPsychology their math systems are fundamentally different]] — Cetans, being [[BlobMonster amorphous and shifting]], think in terms of "flows" from one value to another, and their basic math has more in common with calculus, while they can only conceive of our regular math with difficulty.
91	[[/folder]]
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93	[[folder:Live-Action TV]]
94	* Subverted in an episode of ''Series/BabylonFive''. A probe sent out by an advanced species containing mathematical riddles appears to be this at first... until it's found out the thing's actually a way for the isolationist species to figure out which other races are a threat and destroy them. Fortunately, the probe's fairly stupid.
95	* In the ''Film/CloseEncountersOfTheThirdKind'' parody short "Closet Cases of the Nerd Kind", which features aliens coming down to Earth and hitting people in the face with pies for no apparent reason, some researchers keeps receiving the number 3.14159 and don't understand why. Finally, one character speaks up.
96	-->'''Exposition Guy:''' I was a scientist before I became a bad actor. I know what that number means.\
97	'''Other Character:''' Well? What is it?\
98	'''Exposition Guy:''' It's... pi.
99	* In ''Series/DoctorWho'', this problem is usually absent due to the presence of the TARDIS's [[TranslatorMicrobes Universal Translator]], However, it arises in the episode "[[Recap/DoctorWhoS34E9Flatline Flatline]]" when the Doctor encounters strange 2-dimensional beings, who are so alien that even the TARDIS cannot translate them. The creatures had been abducting and killing people, with the Doctor having hoped they were {{Non Malicious Monster}}s, who are simply so alien and confused by a 3-D world they don't realise they're harming sentient beings. He attempts to communicate with them using the digits of pi. They respond with the number on the jacket of the man they killed, and then [[EvilGloating the number of the one they're about to]].
100	* In the ''Series/{{Farscape}}'' episode "Through The Looking-Glass", Crichton realizes an extradimensional being is trying to communicate with the crew rather than hunt them when he recognises that the talon slashes that it makes in reality are the first few successive prime numbers.
101	%%* On ''Stargate SG-1'', one of several tests set by the Asgard to see whether a colony of humans under their protection was sufficiently advanced to meet the Asgard in person was whether they knew the meaning of pi. This is not an example of this trope, since the Asgard already know that the humans in question are sentient. It actually belongs and is listed under OnlySmartPeopleMayPass, but it's staying here in a comment because people keep trying to add it.
102	* ''Franchise/StarTrek'':
103	** ''Series/StarTrekTheNextGeneration''
104	*** In "Allegiance", Captain Picard is kidnapped by unknown aliens; he attempts to convince them that he's intelligent by repeatedly tapping out the first six prime numbers.
105	*** Downplayed in "Darmok" where the Children of Tama make known their intent to make first contact by sending a SubspaceAnsible transmission that Data describes as a "standard mathematical progression" that doesn't carry any message. Turns out the Tamarians are {{Strange Syntax Speaker}}s and so the rest of the episode involves Picard and the Tamarian captain trying to establish a dialogue.
106	** ''Series/StarTrekVoyager'':
107	*** In "Blink of an Eye", an alien species living on a planet where time moves extremely fast attempt to communicate with ''Voyager'' (or, as they call it, the Sky Ship) via radio by using prime numbers and universal constants. Since, by the time they receive and recognize the signals, the scientist who sent them is long dead, the ''Voyager'' crew don't bother responding.
108	*** Amusingly played with in "Future's End", where after being sent back in time to Earth in the year 1996, they're picked up by an astronomer who attempts to communicate with the "aliens" in orbit by sending the SETI message. A crewman asks Harry if they should respond, to which Harry says, "Absolutely not."
109	* The Twilight Zone episode [[Recap/TheTwilightZone1959S3E28TheLittlePeople The Little People]] has one of a pair of stranded astronauts contact the titular group. When his partner arrives, the first explorer explains that he used math to establish communication with the alien society. He soon uses his ability to communicate with them for a much darker purpose...
110	[[/folder]]
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112	[[folder:Video Games]]
113	* In ''VideoGame/{{Rama}}'' (based on the novel ''Literature/RendezvousWithRama''), the Ramans put many math-based obstacles in your path, presumably for this reason.
114	[[/folder]]
115
116	[[folder:Web Comics]]
117	* ''Webcomic/SchlockMercenary'': When investigating the ancient, planet-sized artifact Oisri, it doesn't take long for people to start noticing that there are too many mathematical coincidences to be anything but intentional. To start with, there's a large effect that is exactly 2063 times the planetoid's radius. This is the first step to deciphering the tools to reading the data Oisri contains.
118	-->'''Kevyn:''' Did you know that the radius of Oisri's grav-mask is exactly--\
119	'''Dietz:''' ''[interrupting]'' Two thousand and sixty three times her radius. We know this. Also, 2063 is the 311th prime number. 311 is the sixty-fourth prime number, and prime factorization of 64 gives us 2 to the 6th.\
120	'''Kevyn:''' Ah. So you've been down this rathole before, then.\
121	'''Dietz:''' Rathole? Irony! Captain. How do you think we knew where to dig?
122	[[/folder]]
123
124	[[folder:Web Original]]
125	* In ''Band'' by Creator/{{Tailsteak}}, [[http://tailsteak.com/archive.php?num=126 intelligence is established]] with square numbers (1, 4, 9, 16)
126	* In ''Literature/FineStructure'', "Eka", AKA "The Script", starts out from prime numbers and works its way up to describe the entire physics of the universe.
127	* Parodied in ''Website/TheOnion'': [[https://www.theonion.com/earth-contacted-by-extraterrestrial-nerds-1819563984 Earth Contacted By Extraterrestrial Nerds]].
128	[[/folder]]
129
130	[[folder:Real Life]]
131	* Conspiracy theorists might believe otherwise, but it is generally accepted that we haven't had any first contact yet to see if this works. Some of the messages we've beamed into space have included prime numbers just in case.
132	* In the free e-book released by NASA ''[[http://www.nasa.gov/connect/ebooks/archaeology_anthropology_and_interstellar_communication.html#.U4xUcij3O2B Archaeology, Anthropology, and Interstellar Communication]]'' it is posited that while math may be great for first contact we may run into some stumbling blocks trying to understand language without any further context to assist a translation. The book cites how for years the Mayan number system was decoded and understood, however scholars were stumped for many years after by the written language. If we had that much trouble with a human language, things may be even harder working out an alien language, even if we can agree on math.
133	* "[[http://www.math.dartmouth.edu/~carlp/PDF/extraterrestrial.pdf Prime Numbers and the Search for Extraterrestrial Intelligence]]" by Carl Pomerance is an academic paper which discusses the idea in depth.
134	* Space probes we sent out of the Solar System (like Pioneer 10) usually contain this in some form. [[note]]Pioneer 10 included a star map telling them [[WeComeInPeaceShootToKill where we are]], even if the probabilities of the probe being found by aliens is ''[[SciFiWritersHaveNoSenseOfScale very low]]''. [[NakedPeopleAreFunny And naked people]]. (That last one to show what humans actually look like. ItMakesSenseInContext -- otherwise the aliens might assume that the probe itself is the intelligent life!)[[/note]]
135	* [[http://en.wikipedia.org/wiki/Lincos_%28language%29 Lincos]] is one possible example of ''how'' to extend the message into actual communication, building up to a complete language from only the natural numbers (fiction, being written by [[WritersCannotDoMath writers]], usually skips this bit).
136	* The notion mentioned above for ''The Andromeda Affair'' ("a repeating sequence with a period that is the product of two primes is an indicator that it represents a [unique] rectangular grid[[note]] A unique rectangle with only two possible useful rotations, thereby reducing arrangement of the data to a ''maximum'' of two simple brute-force attempts[[/note]]") is not a stunning leap of logic for anyone familiar with SETI, since [[http://en.wikipedia.org/wiki/Arecibo_message it's been used in human broadcasts as well]].
137	* The idea of First Contact Math is OlderThanRadio, albeit back then it was more about proving that Earth is inhabited by a sentient species, rather than communicating after having already found out about each other. These early ideas involved sending messages to the Martians by means such as Pythagorean triangles in form of tracts of farmland in the Siberian woods, or ditches filled with burning oil in nighttime Sahara.
138	[[/folder]]

Context Main / FirstContactMath