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Sunday, January 30, 2022

Self-referential humor

From Wikipedia, the free encyclopedia
 
A sign on the wall reading "No thumbtacks on wall", held up with thumbtacks. A sticky note is on the sign with a question mark, and arrows pointing to the thumbtacks. A sticky note is below that sticky note reading "No sticky notes on signs", also on the sign. A sticky note is on that sticky note reading "Sticky note on sign!", with an arrow pointing to the note it is on. A sticky note is on that sticky note reading "No sticky notes on sticky notes". A sticky note is on that sticky note reading "No purple sticky notes", the note is purple.
An example of self-referential humor on a shared noticeboard.

Self-referential humor, also known as self-reflexive humor or meta humor, is a type of comedic expression that—either directed toward some other subject, or openly directed toward itself—is self-referential in some way, intentionally alluding to the very person who is expressing the humor in a comedic fashion, or to some specific aspect of that same comedic expression. Self-referential humor expressed discreetly and surrealistically is a form of bathos. In general, self-referential humor often uses hypocrisy, oxymoron, or paradox to create a contradictory or otherwise absurd situation that is humorous to the audience.

History

Old Comedy of Classical Athens is held to be the first—in the extant sources—form of self-referential comedy. Aristophanes, whose plays form the only remaining fragments of Old Comedy, used fantastical plots, grotesque and inhuman masks and status reversals of characters to slander prominent politicians and court his audience's approval.

Self-referential humor was popularized by Douglas Hofstadter who wrote several books on the subject of self-reference, the term meta has come to be used, particularly in art, to refer to something that is self-referential.

Classification

Meta-jokes are a popular form of humor. They contain several somewhat different, but related categories: joke templates, self-referential jokes, and jokes about jokes (meta-humour).

Joke template

This form of meta-joke is a sarcastic jab at the endless refitting of joke forms (often by professional comedians) to different circumstances or characters without a significant innovation in the humor.

Three people of different nationalities walk into a bar. Two of them say something smart, and the third one makes a mockery of his fellow countrymen by acting stupid.

Three blokes walk into a pub. One of them is a little bit stupid, and the whole scene unfolds with a tedious inevitability. —Bill Bailey

How many members of a certain demographic group does it take to perform a specified task?
A finite number: one to perform the task and the remainder to act in a manner stereotypical of the group in question.

Self-referential jokes

Self-referential jokes must refer to themselves rather than to larger classes of previous jokes.

What do you get when you cross a joke with a rhetorical question?

Three blind mice walk into a bar, but they are unaware of their surroundings so to derive humour from it would be exploitative.

When I said I was going to become a comedian, they all laughed. Well, they're not laughing now, are they?

Jokes about jokes ("meta-humor")

Meta-humour is humour about humour. Here meta is used to describe that the joke explicitly talks about other jokes, a usage similar to the words metadata (data about data), metatheatrics (a play within a play, as in Hamlet), and metafiction.

Other examples

graffiti art on a wall stating "SORRY ABOUT YOUR WALL"
A self-referencing work of graffiti apologizing for its own existence

Alternate punchlines

Another kind of meta-humour makes fun of poor jokes by replacing a familiar punchline with a serious or nonsensical alternative. Such jokes expose the fundamental criterion for joke definition, "funniness", via its deletion. Comedians such as George Carlin and Mitch Hedberg used metahumour of this sort extensively in their routines.

Anti-humor

Anti-humor is a type of indirect and alternative comedy that involves the joke-teller delivering something that is intentionally not funny, or lacking in intrinsic meaning. The humor of such jokes is based on the surprise factor of absence of an expected joke or of a punch line in a narration that is set up as a joke. It depends upon reference to the audience's expectations on what a joke is.

Breaking the fourth wall

Self-referential humor is at times combined with breaking the fourth wall to make explicit reference directly to the audience or to make self-reference to an element of the medium the characters should not be aware of.

Class-referential jokes

This form of meta-joke contains a familiar class of jokes as part of the joke.

Bar jokes

A guy walks into a bar and says "ouch!"

A baby seal walks into a club.

A dangling participle walks into a bar. Enjoying a cocktail and chatting with the bartender, the evening passes pleasantly.

A misplaced modifier walks into a bar owned by a man with a glass eye named Ralph.

A dyslexic man walks into a bra.

A bar was walked into by the passive voice.

A verb walks into a bar, sees a beautiful noun, and suggests they conjugate. The noun declines.

A non sequitur walks into a bar. In a strong wind, even turkeys can fly.

Three logicians walk into a bar. The bartender asks "Do all of you want a drink?" The first logician says "I don’t know." The second logician says "I don’t know." The third logician says "Yes!"

Comedian jokes

The process of being a humorist is also the subject of meta-jokes; for example, on an episode of QI, Jimmy Carr made the comment, "When I told them I wanted to be a comedian, they laughed. Well, they're not laughing now!"— a joke previously associated with Bob Monkhouse.

Limericks

A limerick referring to the anti-humor of limericks:

The limerick packs laughs anatomical
Into space that is quite economical.
But the good ones I've seen
So seldom are clean
And the clean ones so seldom are comical.

W. S. Gilbert wrote one of the definitive "anti-limericks":

There was an old man of St. Bees,
Who was stung in the arm by a wasp;
When they asked, "Does it hurt?"
He replied, "No, it doesn't,
But I thought all the while 'twas a Hornet."

Tom Stoppard's anti-limerick from Travesties:

A performative poet of Hibernia
Rhymed himself into a hernia
He became quite adept
At this practice, except
For the occasional non-sequitur.

Metaparody

Metaparody is a form of humor or literary technique consisting "parodying the parody of the original", sometimes to the degree that the viewer is unclear as to which subtext is genuine and which subtext parodic.

RAS Syndrome

RAS syndrome refers to the redundant use of one or more of the words that make up an acronym or initialism with the abbreviation itself, thus in effect repeating one or more words. However, "RAS" stands for Redundant Acronym Syndrome; therefore, the full phrase yields "Redundant Acronym Syndrome syndrome" and is self-referencing in a comical manner. It also reflects an excessive use of TLAs (Three Letter Acronyms).

Examples

Hedberg

Stand-up comedian Mitch Hedberg would often follow up a joke with an admission that it was poorly told, or insist to the audience that "that joke was funnier than you acted."

Rehnquist

Marc Galanter in the introduction to his book Lowering the Bar: Lawyer Jokes and Legal Culture cites a meta-joke in a speech of Chief Justice William Rehnquist:

I've often started off with a lawyer joke, a complete caricature of a lawyer who's been nasty, greedy, and unethical. But I've stopped that practice. I gradually realized that the lawyers in the audience didn't think the jokes were funny and the non-lawyers didn't know they were jokes.

White

E. B. White has joked about humour, saying that "[h]umour can be dissected, as a frog can, but the thing dies in the process and the innards are discouraging to any but the pure scientific mind."

 

New mysterianism

From Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/New_mysterianism

New mysterianism—or commonly just mysterianism—is a philosophical position proposing that the hard problem of consciousness cannot be resolved by humans. The unresolvable problem is how to explain the existence of qualia (individual instances of subjective, conscious experience). In terms of the various schools of philosophy of mind, mysterianism is a form of nonreductive physicalism. Some "mysterians" state their case uncompromisingly (Colin McGinn has said that consciousness is "a mystery that human intelligence will never unravel"); others believe merely that consciousness is not within the grasp of present human understanding, but may be comprehensible to future advances of science and technology.

Name

Owen Flanagan noted in his 1991 book Science of the Mind that some modern thinkers have suggested that consciousness may never be completely explained. Flanagan called them "the new mysterians" after the rock group Question Mark and the Mysterians. "But the new mysterianism is a postmodern position designed to drive a railroad spike through the heart of scientism". The term "new mysterianism" has been extended by some writers to encompass the wider philosophical position that humans do not have the intellectual ability to solve (or comprehend the answers to) many hard problems, not just the problem of consciousness, at a scientific level. This position is also known as anti-constructive naturalism.

According to Flanagan, "The 'old mysterians' were dualists who thought that consciousness cannot be understood scientifically because it operates according to nonnatural principles and possesses nonnatural properties." Apparently, some apply the terms to thinkers throughout history who suggested some aspect of consciousness may not be knowable or discoverable, including Gottfried Leibniz, Samuel Johnson, and Thomas Huxley. Thomas Huxley wrote, "[H]ow it is that anything so remarkable as a state of consciousness comes about as a result of irritating nervous tissue, is just as unaccountable as the appearance of the Djinn, when Aladdin rubbed his lamp."

The consciousness of brutes would appear to be related to the mechanism of their body simply as collateral product of its working, and to be completely without any power of modifying that working, as the steam-whistle which accompanies the work of a locomotive engine is without influence upon its machinery. Their volition, if they have any, is an emotion indicative of physical changes, not a cause of such changes... The soul stands to the body as the bell of a clock to the works, and consciousness answers to the sound which the bell gives out when it is struck... To the best of my judgment, the argumentation which applies to brutes holds good of men... We are conscious automata.

— Thomas Huxley, "On the Hypothesis that Animals are Automata, and its History", 1874

Philosophy

In the view of the new mysterians, their contention that the hard problem of consciousness is unsolvable is not a presupposition, but rather a philosophical conclusion reached by thinking carefully about the issue. The standard argument is as follows:

Subjective experiences by their very nature cannot be shared or compared side-by-side. Therefore, it is impossible to know what subjective experiences another person is having.

Noam Chomsky distinguishes between problems, which seem solvable, at least in principle, through scientific methods, and mysteries, which do not seem solvable, even in principle. He notes that the cognitive capabilities of all organisms are limited by biology, e.g. a mouse will never be able to navigate a prime number maze. In the same way, certain problems may be beyond our understanding.

Adherents

Historical

  • William James, American philosopher, in his essay "Is Life Worth Living?" (1896). James makes the point that much human mental activity (e.g. reading) is forever closed to the mind of a dog, even though we may share the same household and have a deep friendship with each other. So, by analogy, the human mind may be forever closed to certain aspects of the larger universe. This was a concept which James found liberating, and which gave an implicit significance to certain distressing aspects of the human condition. James makes an analogy with the suffering of a dog during a vivisection: the meaning of the vivisection is inaccessible to the dog. But that does not mean that the vivisection is meaningless. So it may be with our suffering in this world.
  • Carl Jung, Swiss psychiatrist and psychoanalyst, who, in the first chapter of his last work, "Man and His Symbols" (1964), wrote: "...even when our senses react to real phenomena, sights and sounds, they are somehow translated from the realm of reality into that of the mind. Within the mind they become psychic events whose ultimate nature is unknowable (for the psyche cannot know its own psychical substance)."

Contemporary

  • Colin McGinn is the leading proponent of the new mysterian position among major philosophers.
  • Thomas Nagel, American philosopher.
  • Jerry Fodor, American philosopher and cognitive scientist.
  • Noam Chomsky, American linguist, philosopher, cognitive scientist, logician, and political commentator/activist.
  • Martin Gardner, American mathematics and science writer, considered himself to be a mysterian.
  • John Horgan, American science journalist.
  • Steven Pinker, American psychologist; favoured mysterianism in How the Mind Works, and later wrote: "The brain is a product of evolution, and just as animal brains have their limitations, we have ours. Our brains can't hold a hundred numbers in memory, can't visualize seven-dimensional space and perhaps can't intuitively grasp why neural information processing observed from the outside should give rise to subjective experience on the inside. This is where I place my bet, though I admit that the theory could be demolished when an unborn genius—a Darwin or Einstein of consciousness—comes up with a flabbergasting new idea that suddenly makes it all clear to us."
  • Roger Penrose, English physicist, mathematician and philosopher of science.
  • Edward Witten, American string theorist.
  • Sam Harris, American neuroscientist, has endorsed mysterianism by stating that "This situation has been characterized as an “explanatory gap” and the “hard problem of consciousness,” and it is surely both. I am sympathetic with those who, like ... McGinn and ... Pinker, have judged the impasse to be total: Perhaps the emergence of consciousness is simply incomprehensible in human terms."

Opponents

  • Daniel Dennett, American philosopher, who has explicitly attacked McGinn's notion of mysterianism.

Epiphenomenalism

From Wikipedia, the free encyclopedia

Epiphenomenalism is a position on the mind–body problem which holds that physical and biochemical events within the human body (sense organs, neural impulses, and muscle contractions, for example) are causal with respect to mental events (thought, consciousness, and cognition). According to this view, subjective mental events are completely dependent for their existence on corresponding physical and biochemical events within the human body yet themselves have no causal efficacy on physical events. The appearance that subjective mental states (such as intentions) influence physical events is merely an illusion. For instance, fear seems to make the heart beat faster, but according to epiphenomenalism the biochemical secretions of the brain and nervous system (such as adrenaline)—not the experience of fear—is what raises the heartbeat. Because mental events are a kind of overflow that cannot cause anything physical, yet have non-physical properties, epiphenomenalism is viewed as a form of property dualism.

Development

During the seventeenth century, René Descartes argued that animals are subject to mechanical laws of nature. He defended the idea of automatic behavior, or the performance of actions without conscious thought. Descartes questioned how the immaterial mind and the material body can interact causally. His interactionist model (1649) held that the body relates to the mind through the pineal gland. La Mettrie, Leibniz, and Spinoza all in their own way began this way of thinking. The idea that even if the animal were conscious nothing would be added to the production of behavior, even in animals of the human type, was first voiced by La Mettrie (1745), and then by Cabanis (1802), and was further explicated by Hodgson (1870) and Huxley (1874).

Thomas Henry Huxley agreed with Descartes that behavior is determined solely by physical mechanisms, but he also believed that humans enjoy an intelligent life. In 1874, Huxley argued, in the Presidential Address to the British Association for the Advancement of Science, that animals are conscious automata. Huxley proposed that psychical changes are collateral products of physical changes. Like the bell of a clock that has no role in keeping the time, consciousness has no role in determining behavior.

Huxley defended automatism by testing reflex actions, originally supported by Descartes. Huxley hypothesized that frogs that undergo lobotomy would swim when thrown into water, despite being unable to initiate actions. He argued that the ability to swim was solely dependent on the molecular change in the brain, concluding that consciousness is not necessary for reflex actions. According to epiphenomenalism, animals experience pain only as a result of neurophysiology.

In 1870, Huxley conducted a case study on a French soldier who had sustained a shot in the Franco-Prussian War that fractured his left parietal bone. Every few weeks the soldier would enter a trance-like state, smoking, dressing himself, and aiming his cane like a rifle all while being insensitive to pins, electric shocks, odorous substances, vinegar, noise, and certain light conditions. Huxley used this study to show that consciousness was not necessary to execute these purposeful actions, justifying the assumption that humans are insensible machines. Huxley's mechanistic attitude towards the body convinced him that the brain alone causes behavior.

In the early 1900s scientific behaviorists such as Ivan Pavlov, John B. Watson, and B. F. Skinner began the attempt to uncover laws describing the relationship between stimuli and responses, without reference to inner mental phenomena. Instead of adopting a form of eliminativism or mental fictionalism, positions that deny that inner mental phenomena exist, a behaviorist was able to adopt epiphenomenalism in order to allow for the existence of mind. George Santayana (1905) believed that all motion has merely physical causes. Because consciousness is accessory to life and not essential to it, natural selection is responsible for ingraining tendencies to avoid certain contingencies without any conscious achievement involved. By the 1960s, scientific behaviourism met substantial difficulties and eventually gave way to the cognitive revolution. Participants in that revolution, such as Jerry Fodor, reject epiphenomenalism and insist upon the efficacy of the mind. Fodor even speaks of "epiphobia"—fear that one is becoming an epiphenomenalist.

However, since the cognitive revolution, there have been several who have argued for a version of epiphenomenalism. In 1970, Keith Campbell proposed his "new epiphenomenalism", which states that the body produces a spiritual mind that does not act on the body. How the brain causes a spiritual mind, according to Campbell, is destined to remain beyond our understanding forever (see New Mysterianism). In 2001, David Chalmers and Frank Jackson argued that claims about conscious states should be deduced a priori from claims about physical states alone. They offered that epiphenomenalism bridges, but does not close, the explanatory gap between the physical and the phenomenal realms. These more recent versions maintain that only the subjective, qualitative aspects of mental states are epiphenomenal. Imagine both Pierre and a robot eating a cupcake. Unlike the robot, Pierre is conscious of eating the cupcake while the behavior is under way. This subjective experience is often called a quale (plural qualia), and it describes the private "raw feel" or the subjective "what-it-is-like" that is the inner accompaniment of many mental states. Thus, while Pierre and the robot are both doing the same thing, only Pierre has the inner conscious experience.

Frank Jackson (1982), for example, once espoused the following view:

I am what is sometimes known as a "qualia freak". I think that there are certain features of bodily sensations especially, but also of certain perceptual experiences, which no amount of purely physical information includes. Tell me everything physical there is to tell about what is going on in a living brain... you won't have told me about the hurtfulness of pains, the itchiness of itches, pangs of jealousy....

According to epiphenomenalism, mental states like Pierre's pleasurable experience—or, at any rate, their distinctive qualia—are epiphenomena; they are side-effects or by-products of physical processes in the body. If Pierre takes a second bite, it is not caused by his pleasure from the first; If Pierre says, "That was good, so I will take another bite", his speech act is not caused by the preceding pleasure. The conscious experiences that accompany brain processes are causally impotent. The mind might simply be a byproduct of other properties such as brain size or pathway activation synchronicity, which are adaptive.

Some thinkers draw distinctions between different varieties of epiphenomenalism. In Consciousness Explained, Daniel Dennett distinguishes between a purely metaphysical sense of epiphenomenalism, in which the epiphenomenon has no causal impact at all, and Huxley's "steam whistle" epiphenomenalism, in which effects exist but are not functionally relevant.

Arguments for

A large body of neurophysiological data seems to support epiphenomenalism. Some of the oldest such data is the Bereitschaftspotential or "readiness potential" in which electrical activity related to voluntary actions can be recorded up to two seconds before the subject is aware of making a decision to perform the action. More recently Benjamin Libet et al. (1979) have shown that it can take 0.5 seconds before a stimulus becomes part of conscious experience even though subjects can respond to the stimulus in reaction time tests within 200 milliseconds. The methods and conclusions of this experiment have received much criticism (e.g., see the many critical commentaries in Libet's (1985) target article), including recently by neuroscientists such as Peter Tse, who claim to show that the readiness potential has nothing to do with consciousness at all. Recent research on the Event Related Potential also shows that conscious experience does not occur until the late phase of the potential (P3 or later) that occurs 300 milliseconds or more after the event. In Bregman's auditory continuity illusion, where a pure tone is followed by broadband noise and the noise is followed by the same pure tone it seems as if the tone occurs throughout the period of noise. This also suggests a delay for processing data before conscious experience occurs. Popular science author Tor Nørretranders has called the delay the "user illusion", implying that we only have the illusion of conscious control, most actions being controlled automatically by non-conscious parts of the brain with the conscious mind relegated to the role of spectator.

The scientific data seem to support the idea that conscious experience is created by non-conscious processes in the brain (i.e., there is subliminal processing that becomes conscious experience). These results have been interpreted to suggest that people are capable of action before conscious experience of the decision to act occurs. Some argue that this supports epiphenomenalism, since it shows that the feeling of making a decision to act is actually an epiphenomenon; the action happens before the decision, so the decision did not cause the action to occur.

Arguments against

The most powerful argument against epiphenomenalism is that it is self-contradictory: if we have knowledge about epiphenomenalism, then our brains know about the existence of the mind, but if epiphenomenalism were correct, then our brains should not have any knowledge about the mind, because the mind does not affect anything physical.

However, some philosophers do not accept this as a rigorous refutation. For example, Victor Argonov states that epiphenomenalism is a questionable, but experimentally falsifiable theory. He argues that the personal mind is not the only source of knowledge about the existence of mind in the world. A creature (even a zombie) could have knowledge about mind and the mind-body problem by virtue of some innate knowledge. The information about mind (and its problematic properties such as qualia) could have been, in principle, implicitly "written" in the material world since its creation. Epiphenomenalists can say that God created immaterial mind and a detailed "program" of material human behavior that makes it possible to speak about the mind–body problem. That version of epiphenomenalism seems highly exotic, but it cannot be excluded from consideration by pure theory. However, Argonov suggests that experiments could refute epiphenomenalism. In particular, epiphenomenalism could be refuted if neural correlates of consciousness can be found in the human brain, and it is proven that human speech about consciousness is caused by them.

Some philosophers, such as Dennett, reject both epiphenomenalism and the existence of qualia with the same charge that Gilbert Ryle leveled against a Cartesian "ghost in the machine", that they too are category mistakes. A quale or conscious experience would not belong to the category of objects of reference on this account, but rather to the category of ways of doing things.

Functionalists assert that mental states are well described by their overall role, their activity in relation to the organism as a whole. "This doctrine is rooted in Aristotle's conception of the soul, and has antecedents in Hobbes's conception of the mind as a 'calculating machine', but it has become fully articulated (and popularly endorsed) only in the last third of the 20th century." In so far as it mediates stimulus and response, a mental function is analogous to a program that processes input/output in automata theory. In principle, multiple realisability would guarantee platform dependencies can be avoided, whether in terms of hardware and operating system or, ex hypothesi, biology and philosophy. Because a high-level language is a practical requirement for developing the most complex programs, functionalism implies that a non-reductive physicalism would offer a similar advantage over a strictly eliminative materialism.

Eliminative materialists believe "folk psychology" is so unscientific that, ultimately, it will be better to eliminate primitive concepts such as mind, desire and belief, in favor of a future neuro-scientific account. A more moderate position such as J. L. Mackie's error theory suggests that false beliefs should be stripped away from a mental concept without eliminating the concept itself, the legitimate core meaning being left intact.

Benjamin Libet's results are quoted in favor of epiphenomenalism, but he believes subjects still have a "conscious veto", since the readiness potential does not invariably lead to an action. In Freedom Evolves, Daniel Dennett argues that a no-free-will conclusion is based on dubious assumptions about the location of consciousness, as well as questioning the accuracy and interpretation of Libet's results. Similar criticism of Libet-style research has been made by neuroscientist Adina Roskies and cognitive theorists Tim Bayne and Alfred Mele.

Others have argued that data such as the Bereitschaftspotential undermine epiphenomenalism for the same reason, that such experiments rely on a subject reporting the point in time at which a conscious experience and a conscious decision occurs, thus relying on the subject to be able to consciously perform an action. That ability would seem to be at odds with early epiphenomenalism, which according to Huxley is the broad claim that consciousness is "completely without any power… as the steam-whistle which accompanies the work of a locomotive engine is without influence upon its machinery".

Adrian G. Guggisberg and Annaïs Mottaz have also challenged those findings.

A study by Aaron Schurger and colleagues published in PNAS challenged assumptions about the causal nature of the readiness potential itself (and the "pre-movement buildup" of neural activity in general), thus denying the conclusions drawn from studies such as Libet's and Fried's.

In favor of interactionism, Celia Green (2003) argues that epiphenomenalism does not even provide a satisfactory solution to the problem of interaction posed by substance dualism. Although it does not entail substance dualism, according to Green, epiphenomenalism implies a one-way form of interactionism that is just as hard to conceive of as the two-way form embodied in substance dualism. Green suggests the assumption that it is less of a problem may arise from the unexamined belief that physical events have some sort of primacy over mental ones.

A number of scientists and philosophers, including William James, Karl Popper, John C. Eccles and Donald Symons, dismiss epiphenomenalism from an evolutionary perspective. They point out that the view that mind is an epiphenomenon of brain activity is not consistent with evolutionary theory, because if mind were functionless, it would have disappeared long ago, as it would not have been favoured by evolution.

Ultraviolet astronomy

From Wikipedia, the free encyclopedia
 
A GALEX image of the spiral galaxy Messier 81 in ultraviolet light. Credit:GALEX/NASA/JPL-Caltech.

Ultraviolet astronomy is the observation of electromagnetic radiation at ultraviolet wavelengths between approximately 10 and 320 nanometres; shorter wavelengths—higher energy photons—are studied by X-ray astronomy and gamma ray astronomy. Ultraviolet light is not visible to the human eye. Most of the light at these wavelengths is absorbed by the Earth's atmosphere, so observations at these wavelengths must be performed from the upper atmosphere or from space.

Overview

Ultraviolet line spectrum measurements (spectroscopy) are used to discern the chemical composition, densities, and temperatures of the interstellar medium, and the temperature and composition of hot young stars. UV observations can also provide essential information about the evolution of galaxies. They can be used to discern the presence of a hot white dwarf or main sequence companion in orbit around a cooler star.

The ultraviolet universe looks quite different from the familiar stars and galaxies seen in visible light. Most stars are actually relatively cool objects emitting much of their electromagnetic radiation in the visible or near-infrared part of the spectrum. Ultraviolet radiation is the signature of hotter objects, typically in the early and late stages of their evolution. In the Earth's sky seen in ultraviolet light, most stars would fade in prominence. Some very young massive stars and some very old stars and galaxies, growing hotter and producing higher-energy radiation near their birth or death, would be visible. Clouds of gas and dust would block the vision in many directions along the Milky Way.

Space-based solar observatories such as SDO and SOHO use ultraviolet telescopes (called AIA and EIT, respectively) to view activity on the Sun and its corona. Weather satellites such as the GOES-R series also carry telescopes for observing the Sun in ultraviolet.

The Hubble Space Telescope and FUSE have been the most recent major space telescopes to view the near and far UV spectrum of the sky, though other UV instruments have flown on smaller observatories such as GALEX, as well as sounding rockets and the Space Shuttle.

Pioneers in ultraviolet astronomy include George Robert Carruthers, Robert Wilson, and Charles Stuart Bowyer.

Andromeda Galaxy - in high-energy X-ray and ultraviolet light (released 5 January 2016).

Ultraviolet space telescopes

Astro 2 UIT captures M101 with ultraviolet shown in purple

See also List of ultraviolet space telescopes

Ultraviolet instruments on planetary spacecraft

  • United States - UVIS (Cassini) - 1997 (at Saturn from 2004 to 2017)
  • United States - MASCS (MESSENGER) - 2004 (at Mercury from 2011 to 2015)
  • United States - Alice (New Horizons) - 2006 (Pluto flyby in 2015)
  • United States - UVS (Juno) - 2011 (at Jupiter since 2016)
  • United States - IUVS (MAVEN) - 2013 (at Mars since 2014)

George Gamow

George Gamow (March 4, 1904 – August 19, 1968), born Georgiy Antonovich Gamov (Russian: Георгий Антонович Гамов), was a Russian-born American polymath, theoretical physicist and cosmologist. He was an early advocate and developer of Lemaître's Big Bang theory. He discovered a theoretical explanation of alpha decay by quantum tunneling, invented the liquid drop model and the first mathematical model of the atomic nucleus, and worked on radioactive decay, star formation, stellar nucleosynthesis and Big Bang nucleosynthesis (which he collectively called nucleocosmogenesis), and molecular genetics.

In his middle and late career, Gamow directed much of his attention to teaching and wrote popular books on science, including One Two Three... Infinity and the Mr Tompkins series of books (1939–1967). Some of his books are still in print more than a half-century after their original publication.

Early life and career

Gamow was born in Odessa, Russian Empire. His father taught Russian language and literature in high school, and his mother taught geography and history at a school for girls. In addition to Russian, Gamow learned to speak some French from his mother and German from a tutor. Gamow learned English in his college years and became fluent. Most of his early publications were in German or Russian, but he later used English for both technical papers and for the lay audience.

He was educated at the Institute of Physics and Mathematics in Odessa (1922–23) and at the University of Leningrad (1923–1929). Gamow studied under Alexander Friedmann in Leningrad, until Friedmann's early death in 1925, which required him to change dissertation advisors. At the university, Gamow made friends with three other students of theoretical physics, Lev Landau, Dmitri Ivanenko, and Matvey Bronshtein. The four formed a group they called the Three Musketeers, which met to discuss and analyze the ground-breaking papers on quantum mechanics published during those years. He later used the same phrase to describe the Alpher, Herman, and Gamow group.

Upon graduation, he worked on quantum theory in Göttingen, where his research into the atomic nucleus provided the basis for his doctorate. He then worked at the Theoretical Physics Institute of the University of Copenhagen from 1928 to 1931, with a break to work with Ernest Rutherford at the Cavendish Laboratory in Cambridge. He continued to study the atomic nucleus (proposing the "liquid drop" model), but also worked on stellar physics with Robert Atkinson and Fritz Houtermans.

In 1931, Gamow was elected a corresponding member of the Academy of Sciences of the USSR at age 28 – one of the youngest in its history. During the period 1931–1933, Gamow worked in the Physical Department of the Radium Institute (Leningrad) headed by Vitaly Khlopin [ru]. Europe's first cyclotron was designed under the guidance and direct participation of Igor Kurchatov, Lev Mysovskii and Gamow. In 1932, Gamow and Mysovskii submitted a draft design for consideration by the Academic Council of the Radium Institute, which approved it. The cyclotron was not completed until 1937.

Bragg Laboratory staff in 1931: W. H. Bragg (sitting, center): physicist A. Lebedev (leftmost), G. Gamow (rightmost)

Radioactive decay

In the early 20th century, radioactive materials were known to have characteristic exponential decay rates, or half-lives. At the same time, radiation emissions were known to have certain characteristic energies. By 1928, Gamow in Göttingen had solved the theory of the alpha decay of a nucleus via tunnelling, with mathematical help from Nikolai Kochin. The problem was also solved independently by Ronald W. Gurney and Edward U. Condon. Gurney and Condon did not, however, achieve the quantitative results achieved by Gamow.

Classically, the particle is confined to the nucleus because of the high energy requirement to escape the very strong nuclear potential well. Also classically, it takes an enormous amount of energy to pull apart the nucleus, an event that would not occur spontaneously. In quantum mechanics, however, there is a probability the particle can "tunnel through" the wall of the potential well and escape. Gamow solved a model potential for the nucleus and derived from first principles a relationship between the half-life of the alpha-decay event process and the energy of the emission, which had been previously discovered empirically and was known as the Geiger–Nuttall law. Some years later, the name Gamow factor or Gamow–Sommerfeld factor was applied to the probability of incoming nuclear particles tunnelling through the electrostatic Coulomb barrier and undergoing nuclear reactions.

Defection

Gamow worked at a number of Soviet establishments before deciding to flee the Soviet Union because of increased oppression. In 1931, he was officially denied permission to attend a scientific conference in Italy. Also in 1931, he married Lyubov Vokhmintseva (Russian: Любовь Вохминцева), another physicist in Soviet Union, whom he nicknamed "Rho" after the Greek letter. Gamow and his new wife spent much of the next two years trying to leave the Soviet Union, with or without official permission. Niels Bohr and other friends invited Gamow to visit during this period, but Gamow could not get permission to leave.

Gamow later said that his first two attempts to defect with his wife were in 1932 and involved trying to kayak: first a planned 250-kilometer paddle over the Black Sea to Turkey, and another attempt from Murmansk to Norway. Poor weather foiled both attempts, but they had not been noticed by the authorities.

In 1933, Gamow was suddenly granted permission to attend the 7th Solvay Conference on physics, in Brussels. He insisted on having his wife accompany him, even saying that he would not go alone. Eventually the Soviet authorities relented and issued passports for the couple. The two attended and arranged to extend their stay, with the help of Marie Curie and other physicists. Over the next year, Gamow obtained temporary work at the Curie Institute, University of London, and the University of Michigan.

Move to America

In 1934, Gamow and his wife moved to the United States. He became a professor at George Washington University (GWU) in 1934 and recruited physicist Edward Teller from London to join him at GWU. In 1936, Gamow and Teller published what became known as the "Gamow–Teller selection rule" for beta decay. During his time in Washington, Gamow would also publish major scientific papers with Mário Schenberg and Ralph Alpher. By the late 1930s, Gamow's interests had turned towards astrophysics and cosmology.

In 1935, Gamow's son, Igor Gamow was born (in a 1947 book, Gamow's dedication was "To my son IGOR, Who Would Rather Be a Cowboy"). George Gamow became a naturalized American in 1940. He retained his formal association with GWU until 1956.

During World War II, Gamow did not work directly on the Manhattan Project producing the atomic bomb, in spite of his knowledge of radioactivity and nuclear fusion. He continued to teach physics at GWU and consulted for the US Navy.

Gamow was interested in the processes of stellar evolution and the early history of the Solar System. In 1945, he co-authored a paper supporting work by German theoretical physicist Carl Friedrich von Weizsäcker on planetary formation in the early Solar System. Gamow published another paper in the British journal Nature in 1948, in which he developed equations for the mass and radius of a primordial galaxy (which typically contains about one hundred billion stars, each with a mass comparable with that of the Sun).

Big Bang nucleosynthesis

Gamow's work led the development of the hot "big bang" theory of the expanding universe. He was the earliest to employ Alexander Friedmann's and Georges Lemaître's non-static solutions of Einstein's gravitational equations describing a universe of uniform matter density and constant spatial curvature. Gamow's crucial advance would provide a physical reification of Lemaître's idea of a unique primordial quantum. Gamow did this by assuming that the early universe was dominated by radiation rather than by matter. Most of the later work in cosmology is founded in Gamow's theory. He applied his model to the question of the creation of the chemical elements and to the subsequent condensation of matter into galaxies, whose mass and diameter he was able to calculate in terms of the fundamental physical parameters, such as the speed of light c, Newton's gravitational constant G, Sommerfeld's fine-structure constant α, and Planck's constant h.

Gamow's interest in cosmology arose from his earlier interest in energy generation and element production and transformation in stars. This work, in turn, evolved from his fundamental discovery of quantum tunneling as the mechanism of nuclear alpha decay, and his application of this theory to the inverse process to calculate rates of thermonuclear reaction.

At first, Gamow believed that all the elements might be produced in the very high temperature and density early stage of the universe. Later, he revised this opinion on the strength of compelling evidence advanced by Fred Hoyle and others, that elements heavier than lithium are largely produced in thermonuclear reactions in stars and in supernovae. Gamow formulated a set of coupled differential equations describing his proposed process and assigned, as a PhD dissertation topic, his graduate student Ralph Alpher the task of solving the equations numerically. These results of Gamow and Alpher appeared in 1948 as the Alpher–Bethe–Gamow paper. Before his interest turned to the question of the genetic code, Gamow published about twenty papers on cosmology. The earliest was in 1939 with Edward Teller on galaxy formation, followed in 1946 by the first description of cosmic nucleosynthesis. He also wrote many popular articles as well as academic textbooks on this and other subjects.

In 1948, he published a paper dealing with an attenuated version of the coupled set of equations describing the production of the proton and the deuteron from thermal neutrons. By means of a simplification and using the observed ratio of hydrogen to heavier elements, he was able to obtain the density of matter at the onset of nucleosynthesis and from this the mass and diameter of the early galaxies. In 1953 he produced similar results, but this time based on another determination of the density of matter and radiation, at the time at which they became equal. In this paper, Gamow determined the density of the relict background radiation, from which a present temperature of 7 K was predicted – a value which was slightly more than twice the presently-accepted value.

In 1967, he published reminiscences and recapitulation of his own work as well as the work of Alpher and Robert Herman (both with Gamow and also independently of him). This was prompted by the discovery of the cosmic background radiation by Penzias and Wilson in 1965; Gamow, Alpher, and Herman felt that they did not receive the credit they deserved for their theoretical predictions of its existence and source. Gamow was disconcerted by the fact that the authors of a communication[27] explaining the significance of the Penzias/Wilson observations failed to recognize and cite the previous work of Gamow and his collaborators.

DNA and RNA

In 1953, Francis Crick, James Watson, Maurice Wilkins and Rosalind Franklin discovered the double helix structure of the DNA macromolecule. Gamow attempted to solve the problem of how the ordering of four different bases (adenine, cytosine, thymine and guanine) in DNA chains might control the synthesis of proteins from their constituent amino acids. Crick has said that Gamow's suggestions helped him in his own thinking about the problem. As related by Crick, Gamow observed that the 43 = 64 possible permutations of the four DNA bases, taken three at a time, would be reduced to 20 distinct combinations if the order was irrelevant. Gamow proposed that these 20 combinations might code for the twenty amino acids which, he suggested, might well be the sole constituents of all proteins. Gamow's contribution to solving the problem of genetic coding gave rise to important models of biological degeneracy.

The specific system that Gamow was proposing (called "Gamow's diamonds") proved to be incorrect. The triplets were supposed to be overlapping, so that in the sequence GGAC (for example), GGA could produce one amino acid and GAC another, and also non-degenerate (meaning that each amino acid would correspond to one combination of three bases – in any order). Later protein sequencing work proved that this could not be the case; the true genetic code is non-overlapping and degenerate, and changing the order of a combination of bases does change the amino acid.

In 1954, Gamow and Watson co-founded the RNA Tie Club. This was a discussion group of leading scientists concerned with the problem of the genetic code, which counted among its members the physicists Edward Teller and Richard Feynman. In his autobiographical writings, Watson later acknowledged the great importance of Gamow's insightful initiative. However, this did not prevent him from describing this colorful personality as a "zany", card-trick playing, limerick-singing, booze-swilling, practical–joking "giant imp".

Late career and life

Gamow's grave in Green Mountain Cemetery, Boulder, Colorado, US
 
The George Gamow Tower at the University of Colorado Boulder

Gamow worked at George Washington University from 1934 until 1954, when he became a visiting professor at the University of California, Berkeley. In 1956, he moved to the University of Colorado Boulder, where he remained for the rest of his career. In 1956, Gamow became one of the founding members of the Physical Science Study Committee (PSSC), which later reformed teaching of high-school physics in the post-Sputnik years. Also in 1956, he divorced his first wife. Gamow later married Barbara Perkins (an editor for one of his publishers) in 1958.

In 1959, Gamow, Hans Bethe, and Victor Weisskopf publicly supported the re-entry of Frank Oppenheimer into teaching college physics at the University of Colorado, as the Red Scare began to fade (J. Robert Oppenheimer was the older brother of Frank Oppenheimer, and both of them had worked on the Manhattan Project before their careers in physics were derailed by McCarthyism). While in Colorado, Frank Oppenheimer became increasingly interested in teaching science through simple hands-on experiments, and he eventually moved to San Francisco to found the Exploratorium. Gamow would not live to see his colleague's opening of this innovative new science museum, in late August 1969.

In his 1961 book The Atom and its Nucleus, Gamow proposed representing the periodic system of the chemical elements as a continuous tape, with the elements in order of atomic number wound round in a three-dimensional helix whose diameter increased stepwise (corresponding to the longer rows of the conventional periodic table).

Gamow continued his teaching at the University of Colorado Boulder and focused increasingly on writing textbooks and books on science for the general public. After several months of ill health, surgeries on his circulatory system, diabetes, and liver problems, Gamow was dying from liver failure, which he had called the "weak link" that could not withstand the other stresses.

In a letter written to Ralph Alpher on August 18, he had written, "The pain in the abdomen is unbearable and does not stop". Prior to this, there had been a long exchange of letters with his former student, in which he was seeking a fresh understanding of some concepts used in his earlier work, with Paul Dirac. Gamow relied on Alpher for deeper understanding of mathematics.

On August 19, 1968, Gamow died at age 64 in Boulder, Colorado, and was buried there in Green Mountain Cemetery. The physics department tower at the University of Colorado at Boulder is named after him.

Personal life

Gamow had a son, Igor Gamow, with his first wife Rho. The son later became a professor of microbiology at the University of Colorado, as well as an inventor.

Gamow was a well-known prankster, who delighted in practical jokes and humorous twists embedded in serious scientific publications. His most famous prank was the pioneering Alpher–Bethe–Gamow paper, which was serious in its style and content. However, Gamow could not resist adding his colleague Hans Bethe to the list of authors, as a pun on the first three letters of the Greek alphabet.

Gamow was an atheist.

Writings

Gamow was a highly successful science writer, with several of his books still in print more than a half-century after their initial publication. As an educator, Gamow recognized and emphasized fundamental principles that were unlikely to become obsolete, even as the pace of science and technology accelerated. He also conveyed a sense of excitement with the revolution in physics and other scientific topics of interest to the common reader. Gamow himself sketched the many illustrations for his books, which added a new dimension to and complemented what he intended to convey in the text. He was unafraid to introduce mathematics wherever it was essential, but he tried to avoid deterring potential readers by including large numbers of equations that did not illustrate essential points.

In 1956, he was awarded the Kalinga Prize by UNESCO for his work in popularizing science with his Mr. Tompkins... series of books (1939–1967), his book One, Two, Three...Infinity, and other works.

Before his death, Gamow was working with Richard Blade on a textbook Basic Theories in Modern Physics, but the work was never completed or published under that title. Gamow was also writing My World Line: An Informal Autobiography, which was published posthumously in 1970.

A collection of Gamow's writings was donated to The George Washington University in 1996. The materials include correspondence, articles, manuscripts and printed materials both by and about George Gamow. The collection is currently under the care of GWU's Special Collections Research Center, located in the Estelle and Melvin Gelman Library.

Cryogenics

From Wikipedia, the free encyclopedia https://en.wikipedia.org/wiki/Cryogenics...