Instruct: Given a question, retrieve relevant passages that answer the question.
Query: What is the Fermi Paradox?
In 2016, Gray published an article in "Scientific American" about the Fermi paradox, which claims that if extraterrestrials existed, we would see signs of them on Earth, because they would certainly colonize the galaxy by interstellar travel. Gray argues that the Fermi paradox, named after Nobel Prize-winning physicist Enrico Fermi, does not accurately represent Fermi's views. Gray states that Fermi questioned the feasibility of interstellar travel, but did not say definitively whether or not he thought extraterrestrials exist.
Attebery credited Le Guin, among others, of reviving generation ship stories in the 1990s, but wrote that these authors shifted the emphasis of such stories away from individuals towards exploring communal action and belief. Le Guin wished to focus on the "middle generations" in such stories; those generations that lived out their journey in isolation. According to Attebery, Le Guin was able to explore these lives because authors before her had written of the beginning and ending of generation ship journeys. A review of "The Found and the Lost" in the online science fiction magazine "Tor.com" compared "Paradises Lost" and "Vaster than Empires and More Slow", stating that while both stories examined the challenges of interstellar travel and the isolation it brought on, the differences between them were "as stark as they are fascinating". It went on to say that "Paradises Lost" explored the issue of isolation in space travel with "compassion and patience", and called the story the "culmination of the collection, [which drew] together the community-building and existential malaise of all the previous stories into a captivating and ambivalent conclusion". Speaking of the volume as a whole, "Tor.com" stated that it readers home to places they've never visited, and making the familiar stranger and stranger still".
For all its usefulness in resolving questions regarding infinite sets, naive set theory has some fatal flaws. In particular, it is prey to logical paradoxes such as those exposed by Russell's paradox. The discovery of these paradoxes revealed that not all sets which can be described in the language of naive set theory can actually be said to exist without creating a contradiction. The 20th century saw a resolution to these paradoxes in the development of the various axiomatizations of set theories such as ZFC and NBG in common use today. However, the gap between the very formalized and symbolic language of these theories and our typical informal use of mathematical language results in various paradoxical situations, as well as the philosophical question of exactly what it is that such formal systems actually propose to be talking about.
The zombie argument is based on a thought experiment proposed by David Chalmers. The basic idea is that one can imagine, and, therefore, conceive the existence of, an apparently functioning human being/body without any conscious states being associated with it.
As time went by, Bradbury tended to dismiss censorship as a chief motivating factor for writing the story. Instead he usually claimed that the real messages of "Fahrenheit 451" were about the dangers of an illiterate society infatuated with mass media and the threat of minority and special interest groups to books. In the late 1950s, Bradbury recounted:In writing the short novel "Fahrenheit 451", I thought I was describing a world that might evolve in four or five decades. But only a few weeks ago, in Beverly Hills one night, a husband and wife passed me, walking their dog. I stood staring after them, absolutely stunned. The woman held in one hand a small cigarette-package-sized radio, its antenna quivering. From this sprang tiny copper wires which ended in a dainty cone plugged into her right ear. There she was, oblivious to man and dog, listening to far winds and whispers and soap-opera cries, sleep-walking, helped up and down curbs by a husband who might just as well not have been there. This was "not" fiction.
In the third edition of "The Encyclopedia of Science Fiction", author and critic John Clute writes of "Inter Ice Age 4": "It is a complex story set in a near-future Japan threatened by the melting polar ice caps. The protagonist, Professor Katsumi, has been in charge of developing a computer/information system capable of predicting human behavior. Fatally for him, this system predicts his compulsive refusal to go along with his associates and his government in the creation of genetically engineered children, adapted for life in the rising seas. Most of the novel, narrated by Katsumi, deals with a philosophical confrontation between his deeply alienated refusal of the future and the computer's knowing representations of that refusal and the alternatives to it. The resulting psychodramas include a mysterious murder and the enlistment of his unborn child into the ranks of the mutated water-breathers."
The notion of using a fission weapon to ignite a process of nuclear fusion can be dated back to 1942. At the first major theoretical conference on the development of an atomic bomb hosted by J. Robert Oppenheimer at the University of California, Berkeley, participant Edward Teller directed the majority of the discussion towards Enrico Fermi's idea of a "Super" bomb that would use the same reactions that powered the Sun itself.
Forrest J Ackerman is credited with first using the term "Sci-Fi" (analogous to the then-trendy "hi-fi") in 1954. As science fiction entered popular culture, writers and fans active in the field came to associate the term with low-budget, low-tech "B-movies" and with low-quality pulp science fiction. By the 1970s, critics within the field such as Knight and Terry Carr were using "sci-fi" to distinguish hack-work from serious science fiction. Peter Nicholls writes that "SF" (or "sf") is "the preferred abbreviation within the community of sf writers and readers". Robert Heinlein found even "science fiction" insufficient and suggested the term speculative fiction to be used instead, which has continued to be applied to "serious" or "thoughtful" science fiction.
Asteroid 2 Pallas is the third-largest belt asteroid.Asteroid 4 Vesta is the second largest of the asteroids.A common depiction of asteroids (and less often, of comets) in fiction is as a threat, whose impact on Earth could result with incalculable damage and loss of life. This scenario is based on such past events as the impact event responsible for the extinction of the dinosaurs. Such events are, however, sufficiently rare that there is no special reason to expect such an impact in the near future.When the theme of interplanetary colonization first entered SF, the Asteroid Belt was quite low on the list of desirable real estate, far behind such planets as Mars and Venus (often conceived as a kind of paradise planet, until probes in the 1960s revealed uninhabitable temperatures with a deadly carbon dioxide and sulfur atmosphere under its clouds). Thus, in many stories and books the Asteroid Belt, if not a positive hazard, is still a rarely visited backwater in a colonized Solar System.Before colonization of the asteroids became an attractive possibility, a main interest in them was theories as to their origin – specifically, the theory that the asteroids are remnants of an exploded planet. This naturally leads to SF plot lines dealing with the possibility that the planet had been inhabited, and if so – that the inhabitants caused its destruction themselves, by war or gross environmental mismanagement. A further extension is from the past of the existing asteroids to the possible future destruction of Earth or other planets and their rendering into new asteroids.
Water has been detected in interstellar clouds within our galaxy, the Milky Way. Water probably exists in abundance in other galaxies, too, because its components, hydrogen and oxygen, are among the most abundant elements in the universe. Based on models of the formation and evolution of the Solar System and that of other star systems, most other planetary systems are likely to have similar ingredients.
There have been four successful robotically operated Mars rovers. The Jet Propulsion Laboratory managed the "Sojourner" rover, the "Opportunity" rover, "Spirit" rover, and, now the "Curiosity" rover. On January 24, 2016 NASA reported that current studies on Mars by the "Curiosity" and "Opportunity" rovers would be searching for evidence of ancient life, including a biosphere based on autotrophic, chemotrophic or chemolithoautotrophic microorganisms, as well as ancient water, including fluvio-lacustrine environments (plains related to ancient rivers or lakes) that may have been habitable. The search for evidence of habitability, taphonomy (related to fossils), and organic carbon on Mars is now a primary NASA objective. Since June 2018, the "Opportunity" rover has been out of contact after going into hibernation mode in a dust storm. NASA has stated they are unsure if they will ever be able to regain contact.
Although he was the man responsible for its technology, Farnsworth appeared only once on a television program. On July 3, 1957, he was a mystery guest ("Doctor X") on the CBS quiz show "I've Got A Secret". He fielded questions from the panel as they unsuccessfully tried to guess his secret ("I invented electronic television."). For stumping the panel, he received $80 and a carton of Winston cigarettes. Host Garry Moore then spent a few minutes discussing with Farnsworth his research on such projects as high-definition television, flat-screen receivers, and fusion power. Farnsworth said, "There had been attempts to devise a television system using mechanical disks and rotating mirrors and vibrating mirrors—all mechanical. My contribution was to take out the moving parts and make the thing entirely electronic, and that was the concept that I had when I was just a freshman in high school in the Spring of 1921 at age 14." When Moore asked about others' contributions, Farnsworth agreed, "There are literally thousands of inventions important to television. I hold something in excess of 165 American patents." The host then asked about his current research, and the inventor replied, "In television, we're attempting first to make better utilization of the bandwidth, because we think we can eventually get in excess of 2,000 lines instead of 525 ... and do it on an even narrower channel ... which will make for a much sharper picture. We believe in the picture-frame type of a picture, where the visual display will be just a screen. And we hope for a memory, so that the picture will be just as though it's pasted on there."
A phenomenon known as false consensus is closely related to the idea of pluralistic ignorance, and refers to the incorrect belief that others are similar, when in reality they are not. For example, heavy drinkers will think that most others consume as much as they do, and will use this belief to justify their behavior. Berkowitz, an independent consultant who works full-time to promote these ideas, describes false consensus and pluralistic ignorance as "mutually reinforcing and self-perpetuating...the majority is silent because it thinks it is a minority, and the minority is vocal because it believes that it represents the majority" (p. 194).
Putting forward health reasons, in 2011 Soon went from full-time employment by the Smithsonian at the Harvard–Smithsonian Center for Astrophysics to a part-time position. The Center's spokesman said "Willie's opinions regarding climate change are his personal views not shared within our research organization". Its former director Irwin Shapiro said no attempt had been made to suppress Soon's views, and there had been no complaints from other scientists there: "As far as I can tell, no one pays any attention to him." Soon has been defended by others agreeing with his views. In 2013, theoretical physicist Freeman Dyson wrote in an email to "The Boston Globe": "The whole point of science is to question accepted dogmas. For that reason, I respect Willie Soon as a good scientist and a courageous citizen." Republican Senator Jim Inhofe has cited Soon, and Inhofe's former director of communications Marc Morano said that "Willie Soon is a hero of the skeptical movement. When you are an early pioneer, you are going to face the scrutiny and attacks." Soon has links with conservative groups which promote his writings to influence the public debate on climate change, including The Heartland Institute, and the Committee for a Constructive Tomorrow. In a speech at The Heritage Foundation, he accused the IPCC of being "a pure bully" engaged in "blatant manipulations of fact", and said "Stop politicizing science! Just stop!"
Also in 1984, a research team led by Peter Armbruster and Gottfried Münzenberg at the Gesellschaft für Schwerionenforschung (GSI; "Institute for Heavy Ion Research") in Darmstadt, Hesse, West Germany, attempted to create element 108. The team bombarded a target of lead with accelerated nuclei of iron. They reported synthesis of 3 atoms of 108.
Pluralistic ignorance may help to explain the bystander effect. If no-one acts, onlookers may believe others believe action is incorrect, and may therefore themselves refrain from acting.
In a paper published October 31, 2018, the discovery of conclusive evidence that Sagittarius A* is a black hole was announced. Using the GRAVITY interferometer and the four telescopes of the Very Large Telescope (VLT) to create a virtual telescope 130 metres in diameter, astronomers detected clumps of gas moving at about 30% of the speed of light. Emission from highly energetic electrons very close to the black hole was visible as three prominent bright flares. These exactly match theoretical predictions for hot spots orbiting close to a black hole of four million solar masses. The flares are thought to originate from magnetic interactions in the very hot gas orbiting very close to Sagittarius A*.
The probes landed in January 2004 in widely separated equatorial locations on Mars.On January 21, 2004, the Deep Space Network lost contact with "Spirit", for reasons originally thought to be related to a thunderstorm over Australia. The rover transmitted a message with no data, but later that day missed another communications session with the Mars Global Surveyor. The next day, JPL received a beep from the rover, indicating that it was in fault mode. On January 23, the flight team succeeded in making the rover send. The fault was believed to have been caused by an error in the rover's flash memory subsystem. The rover did not perform any scientific activities for ten days, while engineers updated its software and ran tests. The problem was corrected by reformatting "Spirit"'s flash memory and using a software patch to avoid memory overload; "Opportunity" was also upgraded with the patch as a precaution. "Spirit" returned to full scientific operations by February 5.
One possible side effect of the parasite single phenomenon is the increase of the average age of the first marriage (though this is also attributable to other factors, such as career prospects and education). While in 1970, Japanese women married on average at age 24 and men at age 27, by 2002, this had increased to 27.4 years for women and 29 years for men. This has also resulted in women having children later in life, and fewer children overall due to the decline in fertility after age 30. Subsequently, while in 1983 there were on average 1.8 children born to every woman over her lifetime, this has decreased to 1.22 children per woman in 2008.
Some scientists argue that the concept of a circumstellar habitable zone is actually limited to stars in certain types of systems or of certain spectral types. Binary systems, for example, have circumstellar habitable zones that differ from those of single-star planetary systems, in addition to the orbital stability concerns inherent with a three-body configuration. If the Solar System were such a binary system, the outer limits of the resulting circumstellar habitable zone could extend as far as 2.4 AU.
Almost every galaxy has a black hole with a mass of one million to one billion times that of the sun. A super-massive black hole, of more than 4 million solar masses, is located in the center of our own Milky Way galaxy. As the universe has evolved, galaxies often collide and merge, creating larger galaxies. This has led to the supposition that galaxies in mid-merge should have a two great black holes (a pair) orbiting one another. Expectations were, that this should be a common observation, hand in hand with mid merge collisions. However, observation has not validated this supposition; only a few orbiting pairs had been found. When observation did not match expectation, this posed problems for theories of how galaxies merge and grow.
In physics, the Fermi–Pasta–Ulam–Tsingou problem or formerly the Fermi–Pasta–Ulam problem was the apparent paradox in chaos theory that many complicated enough physical systems exhibited almost exactly periodic behavior – called Fermi–Pasta–Ulam–Tsingou recurrence (or Fermi–Pasta–Ulam recurrence) – instead of ergodic behavior. One of the resolutions of the paradox includes the insight that many non-linear equations are exactly integrable. Another may be that ergodic behavior may depend on the initial energy of the system.
An alien agency uses the creation of civilizations and the Fermi Paradox as a means of accumulating and collecting valuable resources.
Hart published in 1975 a detailed examination of the Fermi paradox: the contrast between the extreme likelihood of extraterrestrial life somewhere in the universe and the total absence of any evidence for this. Hart’s work has since become a theoretical reference point for much of the research into what is now sometimes known as the "Fermi-Hart paradox". Concerning Hart's contributions to the study of the paradox, Geoffrey A. Landis writes: "A more proper name for [the paradox] would be the Fermi-Hart paradox, since while Fermi is credited with first asking the question, Hart was the first to do a rigorous analysis showing that the problem is not trivial, and also the first to publish his results". Robert H. Gray argues that the term "Fermi paradox" is a misnomer; he argues that it is not the work of Fermi, nor is it an actual paradox (rather an argument). He views Hart as the proper originator of this argument, in his 1975 paper. Gray therefore proposes, that instead of the (standard, but in his view incorrect) name "Fermi paradox", it should be known as the "Hart-Tipler argument"–acknowledging Hart's priority as the argument's originator, but also acknowledging Frank J. Tipler's substantial extension of Hart's arguments in his 1980 paper "Extraterrestrial intelligent beings do not exist".
Although Fermi's name is most commonly associated with the paradox, he was not the first to ask the question. An earlier implicit mention was by Konstantin Tsiolkovsky in an unpublished manuscript from 1933. He noted "people deny the presence of intelligent beings on the planets of the universe" because "(i) if such beings exist they would have visited Earth, and (ii) if such civilizations existed then they would have given us some sign of their existence." This was not a paradox for others, who took this to imply the absence of ETs, but it was for him, since he himself was a strong believer in extraterrestrial life and the possibility of space travel. Therefore, he proposed what is now known as the zoo hypothesis and speculated that mankind is not yet ready for higher beings to contact us. That Tsiolkovsky himself may not have been the first to discover the paradox is suggested by his above-mentioned reference to other people's reasons for denying the existence of extraterrestrial civilizations.