- Communication with Extraterrestrial Intelligence
CETI (Communication with Extraterrestrial Intelligence) is a branch of
SETI research that focuses on composing and deciphering messages that could theoretically be understood by another technological civilization. The best-known CETI experiment was the 1974Arecibo message composed byFrank Drake andCarl Sagan .CETI research has focused on four broad areas: mathematical languages, pictorial systems such as the Arecibo message, algorithmic communication systems (ACETI) and computational approaches to detecting and deciphering 'natural' language communication.
History
In the nineteenth century there were many books and articles about the possible inhabitants of other planets. Many people believed that intelligent beings might live on the
Moon ,Mars , andVenus ; but since travel to other planets was not yet possible, some people suggested ways to signal the extraterrestrials even before radio was discovered.Karl Gauss suggested that a giant triangle and three squares, thePythagoras , could be drawn on the Siberian tundra. The outlines of the shapes would have been ten-mile wide strips of pine forest, the interiors could be rye or wheat.Joseph Johann Littrow proposed using the Sahara as a blackboard. Giant trenches several hundred yards wide could delineate twenty-mile wide shapes. Then the trenches would be filled with water, and then enough kerosene could be poured on top of the water to burn for six hours. Using this method, a different signal could be sent every night.Meanwhile, other astronomers were looking for signs of life on other planets. In 1822,
Franz von Gruithuisen thought he saw a giant city and evidence of agriculture on the moon, but astronomers using more powerful instruments refuted his claims. Gruithuisen also believed he saw evidence of life onVenus . "Ashen light" had been observed on Venus, and he postulated that it was caused by a great fire festival put on by the inhabitants to celebrate their new emperor. Later he revised his position, stating that the Venusians could be burning their rainforest to make more farmland.Fact|date=April 2008By the late 1800s, the possibility of life on the moon was put to rest. Astronomers at that time believed in the Kant-Laplace hypothesis, which stated that the farthest planets from the sun are the oldest--therefore Mars was more likely to have advanced civilizations than Venus. It was evident that Venus was perpetually shrouded in clouds, so the Venusians probably wouldn't be very good astronomers. Subsequent investigations focused on contacting Martians. In 1877
Giovanni Schiaparelli announced he had discovered "canali" ("channels" in Italian, and mistranslated as "canals") on Mars--this was followed by thirty years of Mars enthusiasm.The inventor
Charles Cros was convinced that pinpoints of light observed on Mars and Venus were the lights of large cities. He spent years of his life trying to get funding for a giant mirror with which to signal the Martians. The mirror would be focused on the martian desert, where the intense reflected sunlight could be used to burn figures into the martian sand.Inventor
Nikola Tesla mentioned many times during his career that he thought his inventions such as hisTesla coil , used in the role of a "resonant receiver", could communicate with other planets [cite book| last =Seifer| first =Marc J.| title =Wizard: the life and times of Nikola Tesla: biography of a genius| publisher =Carol Pub.| date =1996| location =Secaucus, New Jersey| pages =157|chapter=Martian Fever (1895-1896)| isbn = 978-1-55-972329-9 | oclc = 33865102] [Citation| date=July 20, 1931| year=1931| title=Tesla at 75| periodical=Time (magazine)|volume=18|issue=3|pages=3|url=http://www.time.com/time/magazine/article/0,9171,742063-3,00.html.] and even observed repetitive signals of what he believed were Extraterrestrial radio communications coming from Venus or Mars in1899 . However, these "signals" turned out to be terrestrial radiation from nearby planets.Around 1900, The
Guzman Prize was created; the first person to establish interplanetary communication would be awarded 100,000 francs under one stipulation: Mars was excluded because Madame Guzman thought communicating with Mars would be too easy to deserve a prize. [Ley, Willy. Rockets, Missiles, and Space Travel (revised). New York: The Viking Press (1958)]When the Martian canals proved illusory, it seemed that humans were alone in the solar system.
Mathematical and scientific languages
Astraglossa
Published in
1953 byLancelot Hogben describes a system for combining numbers and operators in a series of short and long pulses. In Hogben's system, short pulses represent numbers, while trains of long pulses represent symbols for addition, subtraction, etc.Lincos (Lingua cosmica)
"Lincos: Design of a Language for Cosmic Intercourse", published in
1960 byHans Freudenthal , expands upon Astraglossa to create a general-purpose language derived from basic math and logic symbols.Carl Sagan
The
science fiction novel "Contact" byCarl Sagan explored in some depth how a message might be constructed to allow communication with an alien civilization, using theprime number s as a starting point, followed by various universal principles and facts of mathematics and science. Sagan also authored a non-fiction book on the subject. [Sagan, Carl. Communication with Extraterrestrial Intelligence. MIT Press, 1973, 428 pgs.]Jack McDevitt
In his science fiction novel "
The Hercules Text ",Jack McDevitt describes an extra-terrestrial message based on powers of 2 as a starting point.A language based on the fundamental facts of science
Published in
1992 byCarl Devito andRichard Oehrle , is similar in syntax to Astraglossa and Lincos but builds its vocabulary around known physical properties.Pictorial messages
Pictorial communication systems seek to describe fundamental mathematical or physical concepts via simplified diagrams sent as bitmaps. These messages assume that the recipient has similar visual capabilities (weak assumption) and can understand basic math and geometry (strong assumption because both are prerequisites for building the optimal shape for a radio or optical telescope). A common critique of these systems is that they assume a shared understanding of special shapes, which may not be the case with a species with substantially different vision, and therefore a different way of interpreting visual information.
Pioneer probes
The two
Pioneer plaque s were launched onPioneer 10 andPioneer 11 in 1972 and 1973, depicting the location of the Earth in the galaxy and the solar system, and the form of the human body.Voyager probes
Launched in
1977 , the Voyager probes carried two golden records that were inscribed with diagrams depicting the human form, our solar system and its location. Also included were recordings of pictures and sounds from Earth.The Arecibo message
The
Arecibo message , transmitted in 1974, was a 1679pixel image with 73 rows and 23 columns. It shows the numbers one through ten, the atomic numbers of hydrogen, carbon, nitrogen, oxygen, and phosphorus, the formulas for the sugars and bases in the nucleotides of DNA, the number of nucleotides in DNA, the double helix structure of DNA, a figure of a human being and its height, the population of Earth, our solar system, and an image of the Arecibo telescope with its diameter.Cosmic Call messages
The "
Cosmic Call " messages consisted of few digital sections - "Rosetta Stone", copy of Arecibo Message, Bilingual Image Glossary, the Braastad message, as well as text, audio, video and other image files submitted for transmission by everyday people around the world. The "Rosetta Stone" was composed byStephane Dumas andYvan Dutil and represents a multi-page bitmap that builds a vocabulary of symbols representing numbers and mathematical operations. The message proceeds from basic math to progressively more complex concepts, including physical processes and objects (such as ahydrogen atom). The message is designed with noise resistant format and characters, which make it resistant to alteration by noise. These messages were transmitted in 1999 and 2003 fromEvpatoria Planetary Radar under scientific guidance ofAlexander Zaitsev . Richard Braastad coordinated the overall project.Stars to which messages were sent, are the following: [ [http://www.cplire.ru/rus/ra&sr/VAK-2004.html Передача и поиски разумных сигналов во Вселенной ] ]
Multi-modal messages
Teen-Age Message
The "Teen-Age Message", composed by
Russia n scientists (Zaitsev, Gindilis, Pshenichner, Filippova) and teens, was transmitted from the 70-m dish of Evpatoria Deep Space Center to six Sun-like stars on August 29 and September 3 and 4, 2001. The message consists of three parts:Section 1 represents a coherent-sounding radio signal with slow Doppler wavelength tuning to imitate transmission from the Sun's center. This signal was transmitted in order to help extraterrestrials detect the TAM and diagnose the radio propagation effect of the interstellar medium.
Section 2 is analog information and represents musical melodies, performed on the
Theremin . This electric musical instrument produces a quasi-monochromatic signal, which is easily detectable across interstellar distances. There were seven musical compositions in the 1st Theremin Concert for Aliens.Section 3 represents a well-known Arecibo-like binary digital information: the logotype of the TAM, bilingual Russian and English Greeting to Aliens, and Image Glossary.
Stars to which the message was sent are the following: [ [http://www.cplire.ru/rus/ra&sr/VAK-2004.html Передача и поиски разумных сигналов во Вселенной ] ]
Cosmic Call 2003 message
The "Cosmic Call 2003" message contained text, images, video, music, the Dutil/Dumas message, a copy of the 1974 Arecibo message, BIG = Bilingual Image Glossary, the AI program "Ella", and the Braastad message.
Algorithmic messages
Algorithmic communication systems are a relatively new field within CETI. In these systems, which build upon early work on mathematical languages, the sender describes a small set of math and logic symbols that form the basis for a rudimentary programming language that the recipient can run on a
virtual machine . Algorithmic communication has a number of advantages over static pictorial and mathematical messages, including: localized communication (the recipient can probe and interact with the programs within a message, without transmitting a reply to the sender and then waiting years for a response),forward error correction (the message might contain algorithms that process data elsewhere in the message), and the ability to embed proxy agents within the message. In principle, a sophisticated program when run on a fast enough computing substrate, may exhibit complex behavior and perhaps intelligence.CosmicOS
"
CosmicOS ", designed by Paul Fitzpatrick atMIT , describes avirtual machine that is derived fromlambda calculus .Logic Gate Matrices
"
Logic Gate Matrices " (a.k.a. LGM), developed by Brian McConnell, describes a universalvirtual machine that is constructed by connecting coordinates in an n-dimensional space via math and logic operations, for example: (1,0,0) <-- (OR (0,0,1) (0,0,2)). Using this method, one can describe an arbitrarily complex computing substrate as well as the instructions to be executed on it.Natural Language Messages
This research focuses on the event that we receive a signal / message that is either not directed at us (eavesdropping) or one that is in its natural communicative form. To tackle this difficult but probable scenario, methods are being developed that will first detect if a signal has intelligent-like structure, categorize the type of structure detected and then decipher its content: from its physical level encoding and patterns to the parts-of-speech, which encode internal and external ontologies (Elliott, 2004; Elliott, Atwell & Whyte, 2001).
Primarily, this structure modeling focuses on the search for generic human and inter-species language universals to devise computational methods by which language can be discriminated from non-language and core structural syntactic elements of unknown languages can be detected (Elliott & Atwell, 2000). Aims of this research include: contributing to the understanding of language structure and the detection of intelligent language-like features in signals, to aid the search for extra-terrestrial intelligence (Elliott, 2002a; Elliott 2002b).
The problem goal is therefore to separate language from non-language without dialogue, and learn something about the structure of language in the passing. The language may not be human (animals, aliens, computers...), the perceptual space can be unknown, and we cannot assume human language structure but must begin somewhere. We need to approach the language signal from a naive viewpoint, in effect, increasing our ignorance and assuming as little as possible (Elliott, Atwell & Whyte, 2000; Elliott, 2007).
CETI researchers
*
Frank Drake (SETI Institute):SETI pioneer, composed theArecibo message withCarl Sagan
*Dr John Elliott [http://www.seti-uk.co.uk (SETI Research UK)] : research into developing strategies, which are based on receiving a 'natural' language message, that look at developing algorithms to detect if an ET signal has intelligent-like structure and if so, then how to decipher its content. Author of many papers in this area and a contributor to SETI's book on interstellar communication. Other contributions include message design and construction; member of: International Academy of Astronautics, SETI Permanent Study Group; International Task Group for the Post-detection identification of unknown radio signals.
*Laurence Doyle (SETI Institute): studies animal communication, and has developed statistical measures of complexity in animal utterances as well as human language.
*Stephane Dumas: developed "Cosmic Call" messages, as well as a general technique for generating 2-D symbols that remain recognizable even if corrupted by noise.
*Yvan Dutil : developed "Cosmic Call" messages with Stephane Dumas.
*Paul Fitzpatrick (MIT ): developed "CosmicOS" system based onlambda calculus
*Brian McConnell: developed framework for algorithmic communication systems (ACETI) from 2000-2002.
*Marvin Minsky (MIT AI researcher): first proposed the idea of including algorithms within an interstellar message.
*Carl Sagan (deceased): co-authored the Arecibo message, and was heavily involved inSETI throughout his life.
*Douglas Vakoch (SETI Institute): studies CETI and has published numerous articles, as well as an upcoming book from MIT Press about interstellar communication.
*Alexander Zaitsev (IRE, Russia): composed "Teen Age Message" with Boris Pshenichner, Lev Gindilis, Lilia Filippova, et al., composed "Bilingual Image Glossary" for "Cosmic Call 2003 Message", Scientific Manager of transmitting from Evpatoria Planetary Radar the Cosmic Call 1999, the Teen Age Message 2001, and the Cosmic Call 2003.ee also
*
Active SETI
*Time capsule
*Message in a bottle
*Pioneer plaque References
*Braastad, Richard, The Extraterrestrial Sermons, http://www.richardb.us/project.html
*Dumas, Stepane. The 1999 and 2003 messages explained, http://www3.sympatico.ca/stephane_dumas/CETI/messages.pdf
*Dutil, Dumas, ACTIVE SETI PAGE, http://www3.sympatico.ca/stephane_dumas/CETI/default.htm
*Elliott, J. (2007) A Post-Detection Decipherment Matrix: Acta Astronautica, Journal of the International Academy of Astronautics Elsevier Science Ltd, England, AA2853.
*Elliott, J. (2004) ‘Unsupervised Discovery of Language Structure in Audio Signals, Proceedings of IASTED International Conference on Circuits, Signals and Systems, (CSS 2004), Clearwater Beach, Florida, USA
*Elliott, J. (2002b) ‘The filtration of inter-galactic objets trouvés and the identification of the Lingua ex Machina hierarchy’, Proceedings of World Space Congress: The 53rd International Astronautical Congress, pp. IAA-02-IAA.9.2.10.
*Elliott, J. (2002a) ‘Detecting languageness’, Proceedings of 6th World Multi-Conference on Systemics, Cybernetics and Informatics (SCI 2002), vol. IX, pp. 323-328.
*Elliott, J, Atwell, E & Whyte, B. (2001) ‘First stage identification of syntactic elements’, An extraterrestrial signal in Proceedings of IAC '2001: the 52nd International Astronautical Congress, pp. IAA-01-IAA.9.2.07
*Elliott, J and Atwell, E. (2000) ‘Is anybody out there: the detection of intelligent and generic language-like features’, Journal of the British Interplanetary Society, Vol. 53, pp. 13-22. ISSN: 0007-084X.
*Elliott, J, Atwell, E & Whyte, B. (2000) ‘Increasing our ignorance of language: identifying language structure in an unknown signal’, in Daelemans, W (ed.) Proceedings of CoNLL-2000: International Conference on Computational Natural Language Learning, pp. 25-30 Association for Computational Linguistics
*Martin, Martin C. 1991 SETI Puzzle, posted to sci.crypt, sci.astro, sci.space, rec.arts.sf-lovers and rec.puzzles. http://www.metahuman.org/martin/SETIPuzzle.html
*Communication with Alien Intelligence, 1985, Marvin Minsky, http://web.media.mit.edu/~minsky/papers/AlienIntelligence.html
*Devito, C. and Oerle, R. A Language Based on the Fundamental Facts of Science, Journal of the British Interplanetary Society, 1990, Vol 43, pp. 561-568
*EllaZ Systems, http://www.ellaz.com/AI/Default.aspx
*Freudenthal H 1960 Lincos: Design of a Language for Cosmic Intercourse. North-Holland, Amsterdam.
*Hogben, Lancelot. Science in Authority. New York: W. W. Norton (1963)
*Ley, Willy. Rockets, Missiles, and Space Travel (revised). New York: The Viking Press (1958)
*McConnell, Brian S. 2001 Beyond Contact: A Guide to SETI and Communicating with Alien Civilizations. O'Reilly, Cambridge, MA
*McConnell, Brian S. 2002 Algorithmic Communication with ETI & Mixed Media Message Composition
*McConnell, Brian S at al, 2006?, Between Worlds, SETI Institute/MIT Press
*Minsky, Marvin, talk given at Communication With Extraterrestrial Intelligence (CETI), Proceedings of a conference held at the Byurakan Astrophysical Observatory, Yerevan, USSR, 5-11 September, 1971. Edited by Carl Sagan. Cambridge, MA: The Massachusetts Institute of Technology, 1973., p.ix
*Morrison, P. "Interstellar Communication." Bulletin of thePhilosophical Society of Washington , 16, 78 (1962). Reprinted in A. G. W. Cameron, ed., Interstellar Communication.
*Team Encounter, Cosmic Call 2003, http://web.archive.org/web/20040406151735/www.teamencounter.com/missions/message.asp
*Zaitsev, A. Teen-Age Message, http://www.seti.housenet.org/msg_idx_tam.html
*Zaitsev, A. Interstellar Radio Messages (http://www.cplire.ru/html/ra&sr/index.html in English, http://www.cplire.ru/rus/ra&sr/index.html in Russian)
*Zaitsev, A. Messaging to Extraterrestrial Intelligence (METI), [http://arxiv.org/abs/physics/0610031]
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