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Adnan Khashoggi

Adnan Khashoggi (عدنان خاشقجي; 25 July 1935 – 6 June 2017) was a Saudi businessman and arms dealer known for his lavish business deals and lifestyle. He was estimated to have had a peak net worth of around US$4 billion in the early 1980s.

Early life and education
Khashoggi was born in Mecca, to Muhammad Khashoggi, who was King Abdul Aziz Al Saud's personal doctor, and Samiha Ahmed, a Saudi woman of Syrian origin. Khashoggi's sister was author Samira Khashoggi who married businessman Mohamed Al-Fayed and was the mother of Dodi Fayed. Another sister, Soheir Khashoggi, is a well-known Arab novelist (Mirage, Nadia's Song, Mosaic). He had two brothers, Essam Khashoggi and Adil Khashoggi, and he named Triad Corporation in reference to himself and his two brothers. He was a paternal uncle of murdered journalist, Jamal Khashoggi.

Khashoggi was educated at Victoria College in Alexandria, Egypt, and the American universities Chico State, Ohio State, and Stanford. Khashoggi left his studies in order to seek his fortune in business.

Personal life
In 1961, Khashoggi married 20-year-old Englishwoman, Sandra Daly, who converted to Islam and took the name Soraya Khashoggi. Together they raised one daughter (Nabila) and four sons (Mohamed, Khalid, Hussein, and Omar). They divorced in 1974.

Khashoggi's second wife, the Italian Laura Biancolini, (m. 1978) also converted to Islam and changed her name to Lamia Khashoggi. She was seventeen when she met Adnan; together they had a son, Ali. Khashoggi remained married to Lamia Khashoggi at his death. Adnan's third legal wife was Shahpari Azam Zanganeh (m. 1991-2014). Apart from his marriages, Khashoggi also maintained a harem, and it was reported that he had relationships with at least twelve women who were described as his "pleasure wives". One of them was Jill Dodd, a former model and fashion designer he met in 1980. Dodd has written a memoir named The Currency of Love about their relationship.

In the 1980s, the Khashoggi family occupied one of the largest villa estates in Marbella, Spain, called Baraka, hosting lavish parties. Guests at these parties included film stars, pop celebrities and politicians. In 1985, celebrity reporter Robin Leach reported Khashoggi threw a five-day birthday party in Vienna for his eldest son, and in his heyday, Khashoggi spent $250,000 a day to maintain his lifestyle. He continued to spend lavishly even when he encountered financial problems. His net worth was said to have been down to about $8 million in 1990. Due to his extravagant lifestyle, he was called the Great Gatsby of the Middle East.

Khashoggi also owned Ol Pejeta Conservancy, in Laikipia County, Kenya known at the time as the Mount Kenya Safari Club. His house has since been converted into a hotel which is run by Serena Hotels.

He died on 6 June 2017 while being treated for Parkinson's disease at the St Thomas' Hospital in London. He was 81.

Business career
Khashoggi's early years were spent among some of Saudi Arabia's most influential figures. "While attending school he met Hussein bin Talal, the future King of Jordan. It was at school that Khashoggi first learned the commercial value of facilitating a deal, bringing together a Libyan classmate whose father wanted to import towels with an Egyptian classmate whose father manufactured towels, earning US$1,000 for the introduction. Khashoggi's subsequent education at university would serve as a launchpad for his commercial career."

In one of his first big deals, a large construction company was experiencing difficulties with the trucks that it used on the shifting desert sands. Khashoggi, using money given to him by his father for a car, bought a number of Kenworth trucks, whose wide wheels made traversing the desert considerably easier. Khashoggi made his first US$250,000 leasing the trucks to the construction company, and became the Saudi Arabia-based agent for Kenworth.

In the 1960s and 1970s, Khashoggi helped bring together Western companies and the Saudi Arabian government, to satisfy its infrastructure and defense needs. Between 1970 and 1975, Lockheed paid Khashoggi $106 million in commissions. His commissions started at 2.5% and eventually rose to as much as 15%. Khashoggi "became for all practical purposes a marketing arm of Lockheed. Khashoggi would provide not only an entrée but strategy, constant advice, and analysis", according to Max Helzel, then vice president of Lockheed's international marketing.

A commercial pioneer, he established companies in Switzerland and Liechtenstein to handle his commissions as well as developing contacts with notables such as CIA officers James H. Critchfield and Kim Roosevelt and United States businessman Bebe Rebozo, a close associate of U.S. President Richard Nixon. His yacht, the Nabila, was the largest in the world at the time and was used in the James Bond film Never Say Never Again. After Khashoggi ran into financial problems he sold the yacht to the Sultan of Brunei, who in turn sold it for US$29 million to Donald Trump, who sold it for US$20 million to Prince Al-Waleed bin Talal as part of a deal to keep his Taj Mahal casino out of bankruptcy. Khashoggi gained influence with U.S. President Richard Nixon by donating US$200 million to his 1972 political campaign, through a friendly bank circumventing existing laws that prohibited such large sums from American corporations to political campaigns. Similar arrangements allowed Khashoggi to gain influence with important people throughout the World.

Khashoggi headed a company called Triad International Holding Company which among other things built the Triad Center in Salt Lake City, which later went bankrupt. He was famed as an arms dealer, brokering deals between US firms and the Saudi government, most actively in the 1960s and 1970s. In the documentary series The Mayfair Set, Saudi author Said Aburish states that one of Khashoggi's first deals was providing David Stirling with weapons for a covert mission in Yemen during the Aden Emergency in 1963. Among his overseas clients were defense contractors Lockheed Corporation (now Lockheed Martin Corporation), Raytheon, Grumman Aircraft Engineering Corporation and Northrop Corporation (the last two of which have now merged into Northrop Grumman).

Triad International
Triad International is a multi-national private investment corporation that was owned by Khashoggi. It was named "Triad" after the three brothers, Adnan, Essam and Adil. Its investments include many notable properties and businesses throughout the world. The company consisted of subsidiary companies, including Triad Management, Triad Properties, Triad Energy, Triad Technology, and Triad Financial resources. The global span of the businesses prompted the creation, by the Khashoggi family, of a board-game called Triopoly which was modeled after the classic game of Monopoly. The various game tiles represented properties and companies owned by Khashoggi and his Triad corporation. The game was manufactured and given to family and friends.

Triad International was formed in the early 1960s and as it grew spanned five continents. The company holdings included hotels, shopping centers, banks, oil refineries, a computer manufacturer, a gold mine, construction companies, car and truck franchises, and the Utah Jazz, a professional basketball team. The company was headquartered in Geneva, Switzerland, with its subsidiary companies located in the United States, Canada and Saudi Arabia.

Khashoggi, through Triad, owned the Mount Kenya Safari Club, known as Ol Pejeta Conservancy, a several hundred acre reserve at the foot of Mount Kenya, San Francisco Town Center East, US; a US$250 million property; Long Beach Edgington Oil a US$250 million per year oil refinery in the US; ATV computer systems, Santa Ana, Arizona, US; Colorado Land & Cattle company, Security National bank in Walnut Creek, California, US, Barrick gold mine in Toronto, Canada; Saudi Arabian Kenworth, Chrysler and Fiat car and truck dealerships; the National Gypsum company in Saudi Arabia, and Sahuaro Petroleum in Phoenix, Arizona, US.

The company also had major financial interests in Lloyd's of London; the Manera company; Las Brisas Resort in Acapulco, Mexico; the Houston Galleria; National car rental company; Pyramid Oasis in Cairo, Egypt; Travel Lodge Australia; Pacific Harbor hotel in Fiji; Beirut Riyadh bank; and the bank of Contra Costa.

Khashoggi's Triad real estate holdings included private residences in Beirut; Jeddah; Riyadh; Geneva; Cairo; Salt Lake City, Utah; Cone Ranch, Florida; Rome; Paris; Cannes; London; and a multi-floor penthouse in Olympic Tower in New York.

Khashoggi also owned several private jets, and super-yachts through Triad, including a McDonnell Douglas DC-8 and DC-9, three Boeing 727s, and several smaller business jets and helicopters. His three super-yachts, the Nabila, the Mohammadia, and the Khalidia, were named after his children, Nabila, Mohammed, and Khalid.

Geopolitical involvement
Khashoggi was directly involved in helping to organize and fund the top-secret Operation Moses in 1984 to airlift to safety 14,000 Ethiopian Jews from Sudan to Israel during a famine caused by the Ethiopian Civil War.

Khashoggi was implicated in the Iran–Contra affair as a key middleman in the arms-for-hostages exchange along with Iranian arms dealer Manucher Ghorbanifar and, in a complex series of events, was found to have borrowed money for these arms purchases from the Bank of Credit and Commerce International (BCCI) with Saudi and United States backing. His role in the affair created a related controversy when Khashoggi donated millions to the American University in Washington DC, to build a sports arena which would bear his name. Khashoggi was a member of the university's board of trustees from 1983 until his indictment on fraud and other charges in May 1989. Khashoggi was "principal foreign agent" of the United States and helped establish the supranational intelligence partnership known as the Safari Club.

In 1988, Khashoggi was arrested in Switzerland, accused of concealing funds, and held for three months. Khashoggi stopped fighting extradition when the U.S. prosecutors reduced the charges to obstruction of justice and mail fraud and dropped the more serious charges of racketeering and conspiracy. In 1990, a United States federal jury in Manhattan acquitted Khashoggi and Imelda Marcos, widow of the exiled Philippine President Ferdinand Marcos, of racketeering and fraud.

Khashoggi was a financier behind Genesis Intermedia, Inc. (formerly NASDAQ: GENI), a publicly traded Internet company based in the US. In 2006, Khashoggi was sued by the U.S. Securities and Exchange Commission for securities fraud. The case was dismissed in 2008 and Khashoggi did not admit or deny the allegations.

In January 2003, Seymour Hersh reported in The New Yorker magazine that former U.S. Assistant Secretary of Defense Richard Perle had a meeting with Khashoggi in Marseille in order to use him as a conduit between Trireme Partners, a private venture capital company of which he was one of three principals, and the Saudi government. At the time, Perle was chair of the Defense Policy Board Advisory Committee, a Defense Department advisory group, which provided him with access to classified information and a position to influence defense policy. Khashoggi told Hersh that Perle talked to him about the economic costs regarding a proposed invasion of Iraq. If there is no war,' he told me, 'why is there a need for security? If there is a war, of course, billions of dollars will have to be spent.

Media
In 1991 Khashoggi made an extended appearance on the British television programme After Dark, discussing the Middle East alongside, among others, former Prime Minister Edward Heath and Lord Weidenfeld.

Khashoggi also appeared in Lifestyles of the Rich and Famous in 1985 with host Robin Leach which showcased Khashoggi's extravagant lifestyle.

During his peak, Khashoggi was a well-known figure who frequently appeared in the press and media. He also appeared in various television shows, newspapers, and notable magazine covers such as Time and The Washington Post.

title: Adnan Khashoggi


text:
Talk:Analogy

Multiple Issues
I have replaced reported issues: from unfocused|date=April 2023 overly detailed|date=April 2023 technical|date=April 2023

to

unfocused|date=April 2023 Cite sources|date=June 2023

I think the recent changes have addressed several of the relevant issues in the Talk about over-detailed and technical information, and also have improved the focus in most places (such as by adding a better definition, restructuring, pulling out a lot of material to another article.) So I think the article is in state now where its definition, head and structure are clear, and the worst bamboozling excesses removed; which perhaps leaves the nextmost pressing issue of uncited material. However, if anyone thinks the technical/over detailed is still severe enough to be flagged, please go ahead and add them back.Rick Jelliffe (talk) 16:11, 13 June 2023 (UTC)

Definition
There were several discussions below on the unsatisfactory nature of the definition in the article head.

After a couple of attempts at improving the horrible sentence structure and flow, which made things a little better, but not enough to be useful, I have added as the initial definition the definition from the Oxford Companion to the English language: A comparison or correspondence between two things because of a third element that they are considered to share. (I am not sure how to quote this correctly, so I just put it into double quotes, and gave the citation. Please adjust as appropriate.)

I have also moved the intrusive Etymology to a separate section, as the article on metaphor has.

I have kept the old text, which is aimed at specialists too much, but added a statement about the classic form (A is to B as C is to D) which I think is useful because 1) is is clearer than words, 2) it shows the proportionality aspect (what the text calls analogy of identity, but which I think used to be analogia proportionalitatis.)

Rick Jelliffe (talk) 07:56, 11 June 2023 (UTC)

Vague reference
130.88.0.24 (talk) 22:42, 7 February 2013 (UTC) The reference to Hofsteader in the introduction is vague and it's impossible to find the exact article that is being referred to.

 * I have found a terser link and inserted it. The link is to a seminar overview. But Hofstadter also gives it as chapter 15 of the MIT book The analogical mind: perspectives from Cognitive Science which is in the references section. Rick Jelliffe (talk) 16:27, 13 June 2023 (UTC)

Update category?
Karol, you said that "philosophy" is too general a category. I could agree, but what do you suggest? Analogy comes to philosophy (1) from an argumentative tradition (in "logic", epistemology, metaphysics, ethics, legal theory...) and (2) from present day cognitive studies. It has also very strong (philosophical) connections to language and language related subjects. How should we put it? Actually, I'm starting to think that analogy is indeed a general philosophical subject... Velho 19:35, 10 November 2005 (UTC) Well, I'll change it to "Philosophical arguments"... Velho 19:56, 10 November 2005 (UTC)The

 * It is also a linguistic and theological topic.Rick Jelliffe (talk) 08:34, 11 June 2023 (UTC)

Different Strokes
TWIC ("To Whom It Concerns"), this business with the different arrow directions between source and target has been a headache as long as I can remember, and works against communication between the various traditions, not to mention befuddling novice and expert readers alike. I will work out a more neutral language for relating the different points of view. Jon Awbrey 16:48, 4 January 2006 (UTC)

 * I have removed the section "source and target" because

 * it is fairly incomprehensible
 * it is in the wrong position (certainly not the first section of the article): both because it is too technical and because it could be distributed to specific sections
 * it is partial, not covering all cases
 * it is uncited: while it has a lot of links to other Wikipedia articles, those articles do not support the statement, which means it needs a citation.
 * the information in it seemed to be too obscure or low value: the idea that you go from "typically the more familiar area of experience to the more problematic area of experience" is, apart from the verbosity and being a commonplace of Aristotle, for example. Rick Jelliffe (talk) 08:43, 11 June 2023 (UTC)

Very incomplete and unconclusive article in the Applications in Science and Engineering section
The section called "Aplications on Science and Engineering" is totally incomplete and lacks more analysis and many examples. This presentation underscores the importance that analogies have in the understanding and specially in the teaching of science and Engineering. The article only mentions one of many analogies comparing "electrical circuits to hydraulics". This is not only incomplete, but incorrect as well, since it compares a knowledge field (Hydraulics) to a physical system (electrical circuit); it should say something like: One of the most used analogies is the one comparing several electrical variables to their corresponding hydraulic ones, for example: Voltage is analogous to Pressure, while Current is analogous to fluid Flow, and Electrical Resistance is analogous to fluid flow Restriction (or "Pressure Drop")... therefore, the behaviour of a simple electrical circuit can be easily compared with the behaviour of a familiar and commonly known elevated water tank connected with piping to a lower reservoir, and in that way the modification of a given variable (like elevating the tank or changing the piping diameter) can be easily related and understood, which makes analogy use a powerful tool to predict the effect in an engineering analysis.

There are MANY analogies in Physics, extending between many disciplines, like the analogy of electrical Inductance to Mass (inertia) in an analogous Mechanical system and extending to several other fields. Thus, analogies between separate disciplines can help understand many different phenomena. Just to mention one example: Resonance in the various fields of Acoustics, Mechanics Electronics and even Optics. Analogies can be either strong or "true" or approximate, or "weak", but anyhow useful and important. As it is, the article remains very shallow is these sections. Amclaussen.

 * I have made a minimal change: from "electrical circuits to hydraulics" to "electrical circuits to hydraulic circuits." (I thought hydraulic systems would be better, but I see hydraulic circuit gets used as well.) Rick Jelliffe (talk) 16:49, 13 June 2023 (UTC)

Copy edit
The first paragraph of this article made me cringe. It was so overly complex and difficult to understand:

I changed the first paragraph to:

The rest of the article probably reads just as badly, and is overly complex. I added the tag.

As a law student, I read complex/nasty legislation and cases everyday. My job will be to interpret complex ideas and text. This paragraph was even difficult for me to understand.

Travb (talk) 14:48, 4 March 2007 (UTC)

 * --Agreed, I am not sure if it was changed back or what, but the first paragraph is horrible. Even for those looking for more than a definition, that is quite a confusing and seemingly random way to start an article about a word commonly used to mean "comparison" (slightly simplified, but basically true).Mfergason 14:06, 8 June 2007 (UTC)

 * I'm sure the wording can be improved, but please notice that analogy isn't comparison nor similarity. The word analogy is subject to Wiktionary. In Wikipedia the philosophical and cognitive science subjects of analogy must be addressed. Velho 13:44, 9 June 2007 (UTC)

 * Yes, Analogy is not necessarily a simple comparison A is like B. There is analogy of "proportionality" which means that "the relationship between A and B is like the relationship between X and Y, in some way": for example if you said "the relationship of monarch and subject is like the relation between parent and child": it is not even saying the monarch is directly like a parent or parent is like a monarch but the two relationships are (in some way) alike in that they have the same proportionality.Rick Jelliffe (talk) 06:32, 11 June 2023 (UTC)

At some stage the opening sentence was reverted back, I think correctly. But it was still a mess. I have re-jigged it in two ways, without attempting a better definition:

 * the first is editorial: instead of giving the broad then the narrow definition, I give the narrow then the broader definition. This is less vexing to the grey matter, I think.
 * The second fixes the central problem with the defintion, that it is internally contradictory: it says that analogy is a comparison between two particulars, where one of them is not particular but general! So I have pulled out the "where" sentence and softened it to say that analogies can also have general terms, which is the only thing the original sentence can have meant.

Rick Jelliffe (talk) 06:32, 11 June 2023 (UTC)

 * OK, I bit the bullet and added a new first sentence, see #Definition above.Rick Jelliffe (talk) 16:33, 13 June 2023 (UTC)

Analogy = induction + deduction
In logic, it is pretty obvious that analogy is simply two logical inferences: induction followed by deduction.

Suppose an analogy inference gives p(b) from p(a), this can be reduced to two inferences: By induction: p(a) -> p(x)  (constant a is generalised to a variable x) By deduction: p(x) -> p(b)   (variable x is specialised to a constant b) where p is a predicate symbol, a and b are constants and x is a variable. Clearly there also has to be some additional knowledge that specifies the domain. Presumably the same approach can be extended to more complex logical formulae. Pgr94 14:52, 20 June 2007 (UTC)
 * Charles Sanders Peirce wrote something to this effect. Pgr94 15:46, 20 June 2007 (UTC)

I guess the article already makes clear that sometimes we can go from p(a) to p(b) without accepting (or being able to accept) p(x). See the cited article by Juthe. Besides, what you mean is that analogy gives the same results as induction + deduction give, not that analogy is induction + deduction. Velho 01:52, 22 June 2007 (UTC)
 * The article currently has subsections on reducing analogy to induction ("special case of induction") and reducing analogy to deduction ("Hidden deduction"). Both inferences are inadequate on their own, as you need both.  Not sure about the Juthe paper as it completely fails to mention Peirce who considered the problem nearly a century earlier!  Pgr94 07:30, 22 June 2007 (UTC)

Language needs simplifying
Analogy is both the cognitive process of transferring information from a particular subject (the analogue or source) to another particular subject (the target), and a linguistic expression corresponding to such a process. In a narrower sense, analogy is an inference or an argument from one particular to another particular, as opposed to deduction, induction, and abduction, where at least one of the premises or the conclusion is general. The word analogy can also refer to the relation between the source and the target themselves, which is often, though not necessarily, a similarity, as in the biological notion of analogy.

Some of the language and grammar used within this article needs simplifying. I'm quite highly educated and the first paragraph required me to read over it once or twice to understand fully what it was conveying.--GateKiller (talk) 11:39, 1 September 2008 (UTC)

 * Completely agree with this. I know what an analogy is, but if I didn't then the introductory paragraph would be incredibly difficult to understand. If you happened to be a student trying to brush up on your English then it would be almost incomprehensible. This sentence in particular is extremely poor:

 * "In a narrower sense, analogy is an inference or an argument from one particular to another particular, as opposed to deduction, induction, and abduction, where at least one of the premises or the conclusion is general."

 * In other words, it's a type of argument in which you use a generally accepted example as a comparison to prove a point. Why not simply write that instead of over-complicating a frankly very simple concept. Bandanamerchant (talk) 09:39, 3 August 2013 (UTC)

I have rearranged and split the definition, corrected a contradiction, and adjusted some prepositions, without attempting a much better definition. I think this is an improvement (though improvement would be welcome.) Rick Jelliffe (talk) 06:35, 11 June 2023 (UTC)

full analysis of word origin?
Article refers to 'analogia', translates that as 'proportion'. Does that mean 'analogy' is related to neither 'ana' (as opposed to 'kata'), nor to 'logos'? Or does it simply not make sense to analyze it any further? --84.177.94.31 (talk) 09:52, 13 May 2011 (UTC)

 * No, it means that 'ana' and 'logos' have wider/different meanings than any English term, so when combined they mean something that surprises us. I am surprised by it too, but it is correct that it means 'proportion'. has an explanation.Rick Jelliffe (talk) 08:22, 11 June 2023 (UTC)

Subject or Object
Analogy is both the cognitive process of transferring information from a particular subject (the analogue or source) to another particular subject (the target).

I cannot see in what sense a source and a target can be a subject, and I cannot see how meaning and information can be transferred without knowing at all what information and meaning are, whether they are possible to transfer at all. Like I assume that you are talking about discourse, texts written in a natural language and infomration and meaning are related to those tools.

 * It is horrible. Information is not "transferred" at all, in any idiomatic English sense of "transferring". "Applying" or "asserting" or "arguing" or "positing" or "recognizing" would be better. Rick Jelliffe (talk) 06:40, 11 June 2023 (UTC)

 * In an attempt to be less confusing, I have replaced "from" with "on" and "to" with "onto". This is because transfer denotes that the thing transferred has been removed from its source, which is not the case. I would prefer to use transfer in some way. (I still don't like information/meaning.) Also separated the confusing long sentence by using semi-colon. Please revert if this has made things worse, of course! Rick Jelliffe (talk) 06:53, 11 June 2023 (UTC)

 * OK, I think I can see where the "transferring" terminology comes from: it belongs to the "meta" in "metaphor". Which raises the possibility that it is bogus when describing analogy (outside a direct comparison with metaphor, I guess)...Rick Jelliffe (talk) 08:25, 11 June 2023 (UTC)

Added section on Religion
I have added as section on religion, and given some material in a Catholic section: analogy plays a essential role in theology (according to various recent Popes and theologians) but there is very little material for laymen or on the WWW on it. I am working on a full article on the analogia entis which I will link to when it is up: it is a real gap in Wikipedia, probably because it is so often mentioned only in passing or is an under-the-hood assumption in Catholic material. Rick Jelliffe (talk) 02:36, 27 April 2018 (UTC)

Analogy and complexity: language independence of complexity measure?
In section Analogy, both Kolmogorov complexity and minimum description length is mentioned. In the text, analogical reasoning is implemented by searching for a description (or program) that minimizes some sum of Kolmogorov complexities.

Kolmogorov complexity depends on the description/programming language to be used to describe the various parts of source and target. The existence of a fixed bound $|K_{1}(p) - K_{2}(p)|$ ≤ c1,2, for arbitrary universal programming languages 1 and 2, an appropriate constant c1,2 and every program p, is of no help in establishing that the same program will lead to minimum complexity, no matter in which language it is expressed.

As an example, consider a Turing-complete language ("language 0") that is even more verbose than Cobol, let language 1 be obtained from 0 by adding a very short language construct (say, just "+", as usual) to express addition, and let language 2 be a similar extension of language 0 to express multiplication briefly (say "*"). Then consider the analogy "2 is to 4 as 3 to ?". In language 1, the shortest program will be a description of "x is to x+x" for both source ("2 is to 4") and target ("3 is to ?"), so "?" will be answered as "6". In language 2, the shortest program will amount to "x is to x*x" for both, leading to "? = 9".

So I wonder if the Kolmogorov approach to analogical reasoning depends on the programming language, or not. Likewise, when minimum description length (apparently slightly different from Kolmogorov complexity) is used instead, what about language dependence then? - Jochen Burghardt (talk) 19:42, 6 November 2019 (UTC)

English
What is Analogy 115.147.61.243 (talk) 09:04, 9 September 2022 (UTC)

Dubious
I have marked an uncited paragraph which claims there was no systematic treatment of analogy since Cajetan as dubious. (... perhaps I should have marked it as uncited.) Rick Jelliffe (talk) 05:52, 11 June 2023 (UTC)

Structure-Mapping Theory
There were two very large sections related to Structure Mapping Theory.

 * One set in the Shared Structure section related really to AI/Computer science, so I moved those paragraphs to that subsection.
 * Another large set under Psychology really was unnecessary details on Structure Mapping, with little concerning analogy per se: I have moved it all to the page on Structure mapping. I have kept some paragraphs, which are therefore duplicates, so that the gist/overview is still on the analogy page.

I did these moves boldly, because of the tags that the article had too much tangential etc information. I think it allows the reader to be less bogged down by information that is not quite related to the topic. Rick Jelliffe (talk) 12:06, 11 June 2023 (UTC)

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Talk:Analogy


text:
Talk:Z-order

TODO
TODO:

Please add an example with 3 to 4 windows, how each is refered to.

Add note about z-order of child windows.

Mention different use of X-Y-Z for a physical desktop (horizontal) vs. a computer desktop (typically vertical).

Merge in from z-index
WP:BOLD merge as sufficiently related to add section.Djm-leighpark (talk) 07:25, 24 November 2018 (UTC)

title: Talk:Z-order


text:
Talk:Half-life

Quantum mechanics is important
Yes it IS difficult to understand. How the heck do you know that half sample has "decayed"? You have to measure it! And doing so are you sure that "the moon will still be there"? Please take a look at Schrödinger's cat article first. I suspect that also recent changes performed by people with "UNI physics papers" haven't fully understood its relation with quantum physics even if there is a very interesting wikipedia article about various interpretations of quantum mechanics not to mention the minority ones. Please note that this article has been rated as Start-Class on the project's quality scale and as "High-importance" on the project's importance scale. Have a nice week-end! Maurice Carbonaro (talk) 08:24, 20 July 2012 (UTC)

 * Maurice just put a link to observer (quantum physics), and before that (but I deleted them) links to Measurement in quantum mechanics, Schrödinger's cat, and "Quantum Boolean algebra" . (The last one is strange, the Boolean algebra article says nothing about quantum.) But I don't think any of these links should be there.

 * Decays can often be measured with a Geiger-Müller tube. Every time a particle decays, the computer goes "CLICK". If you start with five atoms, and you hear three CLICKS, then there are two atoms left. You are "observing" it in the same everyday, trivial sense as you would observe anything in the world. Maybe it's true that people generally need to think more deeply about what "observation" means in everyday life, because it is more complicated than it seems---I personally don't think so, but reasonable people can disagree. (The "If a tree falls in a forest" thought experiment has been around for centuries.) But that doesn't mean that every place on wikipedia where some everyday thing is "observed" should include a discussion or link to the deeper analysis of observation. For example, the Tacoma Narrows Bridge (1940) article says in the second paragraph that the bridge was "observed" to rock in the wind. Should we add a link to observer (quantum physics)? In the Wedding of Prince William and Catherine Middleton article, it says the wedding was "watched" by 36.7 million people. Should the word "watched" have a link to observer (quantum physics)? I hope you think these two examples are silly! But really there is no difference between "observing" that my television screen is showing a royal wedding and "observing" that my Geiger-Müller tube has clicked three times. Discussing quantum mechanics is off-topic in both cases. --Steve (talk) 12:40, 20 July 2012 (UTC)
 * Hallo Steve (talk), thanks for giving me the opportunity to exchange views with you on this topic. Please let me tell you that I have been a physics university student albeit dropping out. That was 25 years ago and, believe me, I think I had plenty of time to think about half-life, quantum physics and its relationship to our "trivial everyday world" as we perceive it or, better, how we get conscious about it. Roger Penrose (b.1931), for example, seems to me the scientist that has dedicated a consistent part of his life in analyzing the relationship between consciousness and physics. He wrote and made "trivial" two essays about the subject: The Emperor's New Mind in 1989 which I read thoroughly and Shadows of the Mind which unfortunately I didn't have time to read yet. Citing your examples about the "Tacoma Narrows Bridge (1940) observed to rock in the wind" (well, are we talking about physics here? Then it should be a case of mechanical resonance!) or the "Wedding of Prince William and Catherine Middleton event watched by 36.7 million people"... Ok so people watched it but how? On computers, television sets? These "gadgets" work thanks to millions of transistors that use quantum tunnelling. And even if they weren't like, for example your Geiger-Müller tube this doesn't mean that a many-worlds interpretation is not possible. No, I don't think we should add links to "quantum physics" to the "Weddings of european Royals" as I don't even think these articles should be on any kind of encyclopedia at all like Talk:Wedding dress of Kate Middleton. Last but not least I guess you would think differently about your Geiger-Müller tube if it was in a sealed box containing the Schrödinger's cat: because, let's suppose you have these 5 atoms in the box and this cat would die once your instrument triggers a click at the third atom decaying... How would you know unless you open the box and check if the cat is alive or not? Huh!? So I guess that the main problem here is that we should decide if this encyclopedia should move towards article that have a deeper level of understanding or remain trivial. And for "deeper level of understanding" I mean talking about psychoanalysis like subconscious and collective subconscious. I don't know if you are aware of the fact that physicist Wolfgang Pauli (1900-1958) had a nervous breakdown and a mystical crisis towards the end of his life and he searched Carl Jung (1875-1961) for help. So talking about "this stuff" is not so trivial as it could look like at a superficial glance. What do you think about it? (You are more than welcome to continue this talk with private e-mails) Have a nice Sunday! Maurice Carbonaro (talk) 05:55, 22 July 2012 (UTC)
 * Again, my problem is putting your mention of quantum mechanics here in this article. I have no problem with mentioning quantum mechanics when quantum mechanics is the topic of the article or essential for understanding it. People are reading this article to learn about half life.
 * Quantum mechanics is not necessary to understand half life. For example, you can understand probabilistic decay and half-life by spinning thousands of roulette wheels over and over, and whenever a ball lands on "00" it triggers a mechanism that destroys the wheel. Primary school students for generations have been successfully learning the meaning of probability without understanding a thing about quantum mechanics.
 * Quantum mechanics is not helpful to understand half life. After you have thought deeply about the ontological status of observation, you are not in any better position to understand what the word "half-life" means, nor how to measure or calculate a half-life, nor how to use half-lives to better understand nuclear waste disposal or carbon dating or whatever.
 * Mentioning quantum mechanics is actually counterproductive for understanding half-life. Some readers will say "Yikes, half-life has to do with quantum mechanics?? Better give up on reading this section! This is way beyond my capabilities to understand!"
 * People look up a topic in an encyclopedia to learn about that specific topic--in this case, Half-life. Therefore each article should be about--and only about--that specific topic. Otherwise an encyclopedia would only have one article, called "Things that people ought to know", and that article would be zillions of words long.
 * As for the scientific accuracy of that section, it says "one can start with a single radioactive atom, wait its half-life, and then check whether or not it has decayed". It does not say one word about what the status of the radioactive atom was before the checking occurred. Therefore, the sentence is scientifically accurate, and interpretations of quantum mechanics are irrelevant for this sentence. --Steve (talk) 15:53, 22 July 2012 (UTC)
 * Whateva...! You may find interesting the last changes to the "phenomenon" article in the ==See also section== (I have added a link to the Psychoid archetype). Please feel free to undo... starting a conversation in the talk page. Thanks for your interest in the matter.Maurice Carbonaro (talk) 11:12, 31 July 2012 (UTC)

More on quantum mechanics
As an example, the radioactive decay of carbon-14 is exponential with a half-life of 5730 years. A quantity of carbon-14 will decay to half of its original amount after 5730 years, regardless of how big or small the original quantity was <!--*************"(...) regardless of how big or small the original quantity was (...) "?!?!?!? WOW! Now, I wonder how this latter sentence is NOT connected with 'quantum physics"... How could possibly some "original quantity" "KNOW" which is the amount that we WILL MEASURE IN THE FUTURE in order for us to KNOW if it has decayed or NOT? How is that we are going to pick up and consider the "whole amount of something" and NOT the "wrong half of something" that will NOT decay OR that will decay completely??***********--> --Maurice Carbonaro (talk)
 * I moved this hidden comment out of the main article. Please keep talk on the talk page, that's what it's there for! --Steve (talk) 12:40, 7 August 2012 (UTC)

 * You make it very clear that you have the belief that you are guaranteed to have exactly half the original quantity left after one half-life, and that it cannot happen that all of it has decayed or none of it has decayed after one half-life. If this belief were true, then you would be correct that there would have to be some mystical and supernatural explanation. The atoms would have to magically "know" what you will measure in the future, or Destiny would forbid you from measuring the wrong thing, or who knows what.

 * But this belief is not true!! Not only is it not true, but there is an entire section in the article about how it's not true, and an animation which visually demonstrates the fact that it is not true. I know you read that section because you were discussing it above. But obviously you missed the entire point of it! Sadly, I don't know how to make it any clearer.

 * So it seems to me that this article has been a complete failure in communicating anything about half-life to you. I suggest that you try to learn what half-life is from a different source like  . Maybe one of those will be a more successful teacher. When you finally understand it, you can come back and offer some suggestions about how to make this article clearer. -Steve (talk) 13:03, 7 August 2012 (UTC)
 * Orbital s1.png, which is a  probability distribution  rather than  an orbit . In the figure, the shading indicates the relative probability to "find" the electron, having the energy corresponding to the given quantum numbers, at that point.]]

- Richard Feynman (1918-1988)

 * Hallo there Steve (talk). Thanks for taking my hidden comments to the talk page. I guess you are taking for "deterministically granted" what is instead a "probabilistic measurement". Infact there is an entire section in the article called Half_life. So going back to the half-life article there is a very low probability (IMHO) that the entire "many identical atoms undergoing radioactive decay" could decay ALLTOGETHER just after a microsecond instead of the probabilistic given half-life of "many identical atoms undergoing radioactive decay"' (for instance "zillions of years" like 1.6416 Yottaseconds which is the estimated half-life of the "stable" 20983Bi [ smuth ] radioactive isotope). From this image on the right I have taken from the Electron article/section you will see that in quantum realm we talk about "probabilities". And this is comparable to the "half-life" probabilities we are talking about because in half-life there are mainly beta decays involved. So I am still of the opinion that quantum mechanics is involved in half-life: yes. And I am sure you know that too. Girl and cat.jpg? Better keep on reading this section! This should be in my capabilities to understand!"]] As well as there is a philosophical thought experiment called "If a tree falls in a forest and no one is around to hear it, does it make a sound?" that "has been going on for centuries"... there is also a thought experiment called "Schrödinger's cat" that started "going on" from only last century. What's a cat got to do with quantum mechanics then? There is no failure in communication between us: in one of your previous comments you stated that inserting in the article the concept that half life had to do with quantum mechanics would have "scared" the average reader. (I quote: "Some readers will say "Yikes, half-life has to do with quantum mechanics?? Better give up on reading this section! This is way beyond my capabilities to understand"'') So... what? Cheers. Maurice Carbonaro (talk) 08:04, 8 August 2012 (UTC)

 * As far as I can tell your argument is: "Understanding probability is essential for quantum mechanics. Understanding probability is also essential for understanding half-life. Therefore understanding quantum mechanics is essential for understanding half-life." This is obviously fallacious. If that's not your argument, then you should restate it because I did not catch it.
 * Now you're also making the argument: "Quantum mechanics is important for understanding the mechanism of radioactive decay. Half-life is important for understanding the consequences of radioactive decay. Therefore understanding quantum mechanics is essential for understanding half-life." (If that's not your argument, you should restate it because I did not catch it.) This is also, obviously, fallacious. Half-life can be used to understand any exponential decay, including coin-flipping experiments. While radioactive decay is an important example of exponential decay, understanding its mechanism--which usually involves virtual particles, quantum tunneling, neutrinos, etc.--is not helpful for understanding the exponential decay itself. It is just a distraction, it wastes the reader's time and attention without helping them understand half-life any better.
 * Yes, there is an extremely low but nonzero probability that 100% of 1 trillion atoms of 20983Bi [ smuth ] will all decay within one microsecond. I see how you might have been misled by a sentence in the article so I edited the wording to say "half on average remains" rather than "half remains".
 * By the way, I use quantum mechanics every single day as part of my job. I have taught it to college students. You don't need to explain to me what quantum mechanics is. It is true that I join the overwhelming majority of quantum physicists in believing that quantum mysticism (which you apparently subscribe to) is religion at best, or easily falsified at worst. But that's not the main point. The main point is that discussing quantum mechanics - even if quantum mysticism was true - would be off-topic in this particular article. --Steve (talk) 15:14, 8 August 2012 (UTC)
 * IMHO I understand that you would like the article written under the Copenhagen interpretation which is just one of the many interpretations of quantum mechanics. At this point I suggest to insert a template at the beginning of the article that states this fact like the following:

No. As I explained above in great detail, half-life has nothing to do with quantum mechanics. Or at any rate, it has (more or less) the same amount of relation to quantum mechanics as any random article on wikipedia does. There is no mention of quantum mechanics in this article and it should remain that way. People who subscribe to different interpretations of quantum mechanics will nevertheless have exactly the same understanding of half-life.

I have a guess at what you're trying to get at. This article, like every other article on wikipedia (I mean that literally), implicitly assumes the philosophy of realism -- there is one universe in which things objectively happen. For example, if you are talking to your neighbor, you might say
 * Realism: "It's raining"
 * Non-realism 1: "I have the perception that it is raining"
 * Non-realism 2: "I don't know about what's happening in other universes ... but in this universe, it is raining.
 * Non-realism 3: etc. etc.

Again, look at a random wikipedia article, and you'll see that it uses "realist" descriptions, not the non-realist descriptions, starting from the very first sentence (e.g. "Michael Jackson was a musician..." rather than "I have the perception that Michael Jackson was a musician..."). Do you suggest therefore that every article on wikipedia should have that banner you made above?

In your own everyday life, which kind of description do you use? Realism or non-realism?

I believe that it is possible---indeed, a very good idea---to describe everyday things in realist terms even if realism is not fundamentally true. I don't think that people should apologize or qualify statements like "It is raining". (Or "The atom has radioactively decayed" or whatever.) Regardless of its fundamental truth or falsehood, realism has an obvious practical value in talking to people and making decisions in everyday life ... not to mention writing encyclopedia articles!! :-) --Steve (talk) 12:47, 24 August 2012 (UTC)
 * There is no mechanism in Newtonian mechanics for anything like nuclear decay. That is 100% quantum mechanics. Alpha decay is well modeled by alpha particles moving at the Fermi energy and tunneling out of the nucleus. There is not quite as good a model for beta decay, but it is still related to quantum mechanics. Also, there is no way to describe radioactive decay as other than probabilistic. In some cases, the numbers are large enough that a continuum approximation is close, or even best, but underlying it is probability. Gah4 (talk) 02:09, 6 September 2021 (UTC)
 * There is no mechanism in Newtonian mechanics for anything like nuclear decay. That is 100% quantum mechanics. Alpha decay is well modeled by alpha particles moving at the Fermi energy and tunneling out of the nucleus. There is not quite as good a model for beta decay, but it is still related to quantum mechanics. Also, there is no way to describe radioactive decay as other than probabilistic. In some cases, the numbers are large enough that a continuum approximation is close, or even best, but underlying it is probability. Gah4 (talk) 02:09, 6 September 2021 (UTC)

The acceptance of the Copenhagen interpretation among physicists
Hallo there Steve (talk), back to this talk after almost 5 months. Well I dunno if you have taken a look at the Copenhagen_interpretation article/section. I quote: "''(...) According to a poll at a Quantum Mechanics workshop in 1997, the Copenhagen interpretation is the most widely-accepted specific interpretation of quantum mechanics, followed by the many-worlds interpretation. Although current trends show substantial competition from alternative interpretations, throughout much of the twentieth century the Copenhagen interpretation had strong acceptance among physicists. Astrophysicist and science writer John Gribbin describes it as having fallen from primacy after the 1980s. (...)"  And it's all well referenced as well... it makes you think, huh? We are in the second decade of the XXI century now...   M  aurice    C arbonaro     08:56, 31 January 2013 (UTC)

 * This is the talk page for the article Half-life. We should not be using it for discussions of anything except how to improve this article.

 * I explained above in excruciating detail why I think it would be inappropriate, in the half-life article, to discuss quantum mechanics or put links to quantum mechanics articles. (Just like I think it would be inappropriate to discuss quantum mechanics in the Julius Caesar article.) My argument does not rely on the truth or falsehood of any particular interpretation of quantum mechanics. No matter what interpretation of quantum mechanics is correct, quantum mechanics should not be discussed in the half-life article (any more than the Julius Caesar article). If you think that quantum mechanics should be part of this article, then you need to carefully read what I wrote above and specifically respond to it. If you just generally want to discuss quantum mechanics with someone, do it at User talk:Sbyrnes321 or http://www.physicsforums.com/ :-D --Steve (talk) 04:17, 12 February 2013 (UTC)

 * Please avoid wp:sarcasm and wp:pas. I don't see how "Julius Caesar" could have something to do with quantum mechanics. And anyway I am endorsing the fact that this article seems to be mainly written according to the Copenhagen interpretation, which is just *ONE* of the quantum mechanics interpretations. Usually talk pages shouldn't be used for "general conversations" about the subject of the article. According to the definition of "quantum mechanics" (QM – also known as quantum physics, or quantum theory) is a branch of physics dealing with physical phenomena at microscopic scales, where the action is on the order of the Planck constant.. Considering the concept of "Julius Caesar" in his "wholeness" obviously there is nothing to do with the "quantum world" ... but if we start talking about radioactive decay I guess we have all the right to state that we are dealing with phenomena that belong to the quantum world at a Planck scale. I have checked last 500 contributions made on the Interpretations of quantum mechanics article and didn't find one single contribution by User "Sbyrnes321" (that's you) not to mention Talk:Interpretations of quantum mechanics. I beg your pardon but I must say that I have strong reservations that you haven't wholly understood what all "quantum mechanics" is about. Is not that I am saying that I master the whole subject... but... well... at least I am open to discuss about it. On wikipedia. Not on external links (thanks anyway). BTW "(...) excruciating detail (...)" doesn't apply very much to quantum physics where the Heisenberg uncertainty principle makes sense. Please avoid considering phsyics subjects as ballast tanks that haven't got anything else to do with each other. I wrote <tt>"physics"</tt> not <tt>"ancient Rome history"</tt>. Thanks for reading you. Catch you L8R. (I am available for private e-mailing) . <span style="border:2px solid green;background:black;padding:1px;color:green;text-shadow:green 0.2em 0.2em 0.4em">  M  aurice   <span style="border:2px solid green;background:black;padding:1px;color:green;text-shadow:green 0.2em 0.2em 0.4em"> C arbonaro     09:01, 13 February 2013 (UTC)

 * Which part of the article is written "according to the Copenhagen interpretation"? Can you please point to a specific sentence? If you believe that that sentence is written according to the Copenhagen interpretation, then how would you rewrite it to not be according to the Copenhagen interpretation?

 * It is my opinion that this article, like the Julius Caesar article, is neither "according to the Copenhagen interpretation" nor "according to some other interpretation", because the article has nothing to do with quantum mechanics. As I wrote above, quantum mechanics is related to the mechanism of radioactive decay, while half-life is related to the consequences of radioactive decay. The previous sentence is not evidence of a connection between half-life and interpretations of quantum mechanics. By the same token, rotational inertia is related to the mechanism of flipping coins, while half-life is related to the consequences of flipping coins. The previous sentence is not evidence of a connection between half-life and rotational inertia. Even if there was no such thing as radioactive decay or atoms or quantum mechanics in our universe, we would still invent the exact same concept of half-life, not even slightly modified, to describe other random exponential-decay processes.

 * I do not dogmatically regard different physics subjects as unrelated ballast tanks. When two aspects of physics are related to each other, I am enthusiastic about pointing out the connection. For example, I recently wrote an article describing the various mathematical relations between thermal diffusion, viscosity, electron flow in semiconductors, etc. But I am always opposed to making up a connection where none actually exists (or as I call it, "going off on unrelated tangents"). Just because two things are part of physics does not mean that they are connected. The Tsiolkovsky rocket equation article should not include a discussion of Wannier functions, even though both are physics. My opinion / guess from this conversation (and I could be wrong) is that you don't have a deep, thorough, detailed, quantitative understanding of either quantum mechanics or half-life, and you noticed some superficial overlap between the two things, e.g. they both involve the word "radioactive". I think you jumped from there to the (incorrect) conclusion that these two things are kinda part of the same subject. They're not. It's just superficial.

 * As for credentials, I am a PhD physicist who uses quantum mechanics every day as part of my job. No, I haven't edited the Interpretations of quantum mechanics article. Does that prove my ignorance??? I did write the majority of Measurement in quantum mechanics back in 2007 for what it's worth. And much of density matrix and many many others. But I hope that my arguments stand for themselves! :-D --Steve (talk) 04:34, 14 February 2013 (UTC)

 * Thanks for answering.
 * Okay let's put it this way then Ph.D. Byrnes.
 * This article has been rated for a long time as "Start-Class" on the project's quality scale (i.e. "<tt>Provides some meaningful content, but the majority of readers will need more.</tt>") and as High-importance on the project's importance scale (which is divided in four grades: <tt>Top, High, Mid, Low</tt>).
 * IMHO I don't believe you need a Ph.D. to suspect that there is something strange about this article if we are all stuck at this paradoxical point. This should make us wonder:
 * <tt>does this mean that the article is far for being "complete"?</tt>
 * You are setting a difference between "mechanisms" and "consequences" which IMHO clearly states your holistic causalism view of *all* physics which is something I don't endorse, but which I respect and which AFAIC is known as "Copenhagen interpretation".
 * Consequences of flipping coins? With all due respect I have visited this latter page and honestly I found it a forced oversemplification.
 * Not to mention the "capitalistic interpretation" (not the "Copenhagen" one) of substituting coins for atoms. (and I am not even a communist!) :D LOL.
 * BTW have you ever heard of
 * Fritjof Capra,
 * Brian David Josephson and
 * the concept of synchronicity?
 * Because I would be really interested in what do you think about these two (living) guys and the latter concept. Even privately because I don't like being publicly accused for "<tt>going off on unrelated tangents</tt>". ;-) Stating that you are "<tt>always opposed to making up a connection where none actually exists</tt>" rings me a bell of someone else that opposed speculating on "pure void" <tt>(What was *there* before the Big Bang? Quantum vacuum?)</tt> . Please let's try to have a nice and relaxed week-end. <span style="border:2px solid green;background:black;padding:1px;color:green;text-shadow:green 0.2em 0.2em 0.4em">  M  aurice   <span style="border:2px solid green;background:black;padding:1px;color:green;text-shadow:green 0.2em 0.2em 0.4em"> C arbonaro      08:46, 16 February 2013 (UTC)

 * I'm sorry that I was condescending before...
 * Mechanisms vs consequences: I don't think I am making any deep philosophical point here! Here is a more pedestrian example. (1) The Krebs cycle is an important mechanism for Julius Caesar's being alive. (2) The Roman Empire is an important consequence of Julius Caesar's being alive. (3) Nevertheless, it is OK that the article Roman Empire does not discuss the Krebs cycle. Do you agree with (1-3)? If so, then it seems you have the same philosophical view of consequences versus mechanisms as I do! You're just disagreeing with me about the facts of this one particular case. :-D
 * Is the Julius Caesar article written "according to the Copenhagen interpretation"? What about Tsiolkovsky rocket equation? I'm just trying to understand what you're arguing, these questions are not rhetorical or mocking.
 * There are about 16,000 physics articles on wikipedia right now. Is it your opinion that a discussion of the various interpretations of quantum mechanics (and/or synchronicity, etc. etc.) should be in all 16,000 of these articles? Or half of them? Or 1% of them? Or what? Am I correct to understand that each physics article which lacks a discussion of the various interpretations of quantum mechanics is "written according to the Copenhagen interpretation"? If not, what is the criteria by which you to judge an article to be "according to the Copenhagen interpretation"?
 * If you ask me about Capra, Josephson, and synchronicity, I will give you the same answer as if you ask me about the possibility of extraterrestrial  intelligence, or about financial regulations: This is a topic that has nothing to do with half-life. No matter whether you think Josephson is a visionary or a lunatic, or if you've never heard of him, you can still understand half-life equally well! I hope people formulate knowledgeable opinions about Capra, Josephson, and synchronicity, just like I hope people formulate knowledgeable opinions about the possibility of extraterrestrial intelligence. But I don't think we should be teaching about it in this particular article. :-P
 * I don't see how it's a "paradox" that this article is rated start-class. Quite generally across wikipedia physics articles, almost nobody ever changes that page rating, even when the page gets dramatically better or worse. No one feels that it's their place to change the rating. I personally don't think that this article is start-class. That rating is just one person's opinion, and even worse, it's an opinion about an older version of the article. Can the article be improved by expanding it? Yes, I won't deny that. For example, the article could be improved by adding a table of the half-lives of important nuclides, etc. etc. But the article could also be made worse by expanding it, if the expansion is off-topic (like a discussion of financial regulations, to take an extreme example). I am arguing that discussing interpretations of quantum mechanics is in the latter category. --Steve (talk) 23:13, 17 February 2013 (UTC)
 * Just to add my two cents... Half life is a classical description of reality. See my talk post below which discusses half life in the context of a chemical system. I don't think a discussion of quantum physics is really appropriate for a half-life discussion. First, its meaning breaks down when you move from classical systems described by continuous differential equations (of which half life arises from) to discrete systems based on probabilities. In addition, atomic decay is an odd issue in that most of it can be described by classical physics. For example, neutron energy is a mass problem, not a wavelength issue such as with the photon. So the discussion of quantum mechanics, here, seems like a non sequitur, which puts me in agreement with Steve. Sean Egan (talk) 21:29, 28 February 2013 (UTC)

Proposing section on application of half life to chemistry
Many chemistry students Google "Half-life" only to be forwarded to this page. I want to add a section on the application of half life through a derivation. I know this has been done before, but I feel that it isn't as clear as it could be. Students often need to see steps which spell out not only the math, but the reasoning. I also see a lot of contention regarding quantum mechanics and nuclear decay. (Nuclear decay doesn't really follow QM as much as it does classical physics, but whatever...) I'm proposing a chemical example, which is definitely described by classical physics. Tell me what you guys think! I'd like to add it as an aside or as a collapsable example:

Consider the following first order decay of A to B.

$$A\rightarrow B$$

We could describe half life through this by solving the differential equation which follows the conversion from A to B via a rate constant k, and then solve for the time when half of A is gone.

$$\frac{d[A]}{dt}=-k[A]$$ $$\frac{d[A]}{[A]}=-kdt$$

We will integrate this differential equation from Ai, or the initial concentration of A to Af, or the final concentration of A.

$$\int_{[A]_{i}}^{[A]_{f}}\frac{d[A]}{[A]}=\int_{t=0}^{t}-kdt$$

$$ln[A]_{f}-ln[A]_{i}=-kt+k(0)$$

$$ln\frac{[A]_{f}}{[A]_{i}}=-kt$$

We may raise both sides to the power of e, thus eliminating the natural log:

$$e^{ln\frac{[A]_{f}}{[A]_{i}}}=e^{-kt}$$

$$\frac{[A]_{f}}{[A]_{i}}=e^{-kt}$$

$$[A]_{f}=[A]_{i}e^{-kt}$$

We now have an equation which solves for the final concentration of A. Assume that we want to know at what time only half of A will be left. We could set Af equal to 1/2 of Ai:

$$[A]_{f}=\frac{1}{2}[A]_{i}$$

This simplifies our equation to:

$$\frac{1}{2}[A]_{i}=[A]_{i}e^{-kt}$$

Where we may cancel Ai to yield

$$\frac{1}{2}=e^{-kt}$$

We could then solve for t by taking the natural log of both sides, and then divide by -k to solve for the time at which only half of A remains, which would be the half-life:

$$\frac{ln\frac{1}{2}}{-k}=t$$

$$\frac{0.693}{k}=t$$

I believe this gives a better understanding of where the half comes from in half-life. It's described by these equations as the time at which half of the initial species remains. Does anyone agree? Sean Egan (talk) 21:13, 28 February 2013 (UTC)

 * I like the idea of starting the article with a (brief) discussion of exponential decay in general -- where it comes from, what interesting properties does it have, etc. Some of the text could be copied from exponential decay.

 * But I wouldn't put the differential equation derivation (above) into that discussion. I would guess that 95% of readers of this article don't know the first thing about calculus, then another 4.9% are capable of kinda following the math but only a hazy idea of what it means, and only the last 0.1% will understand the concept better by reading through the math there. (By the way, I'm speaking very specifically about what you proposed, as I understand it. I'm not against math in articles in general -- I've added math to tons of articles including this one -- but it needs to be placed and described appropriately.) Anyway, the differential equation stuff is already in exponential decay, perhaps it could be summarized more briefly with a link to exponential decay. Just my opinion :-D --Steve (talk) 20:19, 19 November 2013 (UTC)

Move Section - Probabilistic Nature of Half Life
Many high school and under graduate students come to this page for a description of half-life which will help them in their studies. I suggest we move the probabilistic nature of half life to the end of the article, as it is furthest from what the average user on this site would be looking for, and is probably the most confusing. Please see my previous talk post as an example of what I believe to be relevant, important aspects of the concept of half life. Sean Egan (talk) 21:34, 28 February 2013 (UTC)

I agree that this section needs to be moved, but I think that the beginning of the article needs a lot more attention. I would recommend that it be rewritten in the standard method of an undergraduate physics text on radioactive decay. That means just a little more history on the term other than mentioning Rutherford, followed by the small set of standard formulas - basically just
 * $$N(t) = N_0 e^{-\lambda t} \,$$

and
 * $$t_{1/2} = \frac{\ln (2)}{\lambda} = \tau \ln(2)$$

Then you introduce the standard units of measurement and give a few examples possibly with a supporting graph or picture.

After that, then one can talk about the probabilistic nature of the phenomenon observed in physics, but this needs to be addressed in terms of the solution of the time dependent Shrodinger equation, the transition probabilty, Fermi's Golden Rule, and the energy-time uncertainty relationship. Not just in terms of the law of large numbers, or focusing too much on the boolean character of the decay phenomenon.

I acknowledge that this is not the Exponential decay article, which offers most of this detail.. But that's also a good reason that the probabalistic interpretation needs to be moved out of the first part of the article (the probabalitic interpretation is only in regards to nuclear decay, or another discrete random process). HappyDa (talk) 05:44, 7 March 2013 (UTC)

 * It's agreed then, we should change up this article. I'll wait to see if anyone else has any thoughts, as I've noticed quite a few recent posts to this talk page. If I don't hear anything else, I'll start moving content around. I also agree with your concern regarding the beginning of the article. I don't think it serves the community well as it is, and should be expanded. I wrote a derivation of half life above this talk post in terms of chemical species, but I could re-write it in terms of nuclear decay. I wouldn't have to copy all the equations, but just the main idea. Does anyone have a problem with that ? Sean Egan (talk) 18:55, 7 March 2013 (UTC)

 * Well I'm not sure I agree, actually.. I don't think this article needs to jump into derivations right off the bat either.  I think that all you need to do is introduce the exponential decay formula, define its variables, and then show what happens when you substitute:
 * $$N = \frac{1}{2} N_o$$
 * That leads you to the second formula, defining the half life. There is no mention of math or physics in that part - it's just a feature of exponential decay.
 * That being said, I think that if there should be any leaning towards a particular branch of science when doing the explanation, I would think it should be physics. This term is widely known for its application in nuclear radioactive decay, as that's where it was coined.  I certainly don't think that the derivation of the term should start by its application in study of chemical species.  If that is mentioned, it should be in a section of its own, but not in the introduction or the first section - it should be more like the Half-life in biology and pharmacology section. HappyDa (talk) 06:37, 8 March 2013 (UTC)
 * So you don't agree that we should move the probabilistic section down the page? If not, I'll let it sit there. In addition, I had some students take a look at the current definitions of half life. It took 4 freshman physics students quite a while to figure out what was being stated. I think there could be some additional clarity. For example, one student was interested in knowing where the exponential and natural logarithms come from. Why do they arise? This isn't currently stated. Sean Egan (talk) 19:31, 14 March 2013 (UTC)
 * I agree that the probabilistic section needs to be moved down, yes. I just didn't agree that the front section should be introduced in terms of chemical species - that's what you were suggesting above, and I think it should be introduced in terms of nuclear radioactive decay, just like it is now.  We just need to expand it a bit, and yes, the probabilistic section is way too prominent, and it is not explained very clearly. HappyDa (talk) 04:01, 15 March 2013 (UTC)

I think the problem with the probabilistic section is not that it is in the wrong place but that it desperately needed shortening and copy-editing. (I think I wrote it originally ... Sorry! :-P ) I just shortened it ... hope that helps ... :-D --Steve (talk) 02:11, 19 November 2013 (UTC)

Simple table at the top
The table at the top of the article simply illustrates the concept in numerical sequence. The introduction of 1/e (in red?) seems to serve no purpose and breaks the "halving sequence" the table illustrates - also the formatting creates errors. The use of math formatting for the simple fractions involved seems rather pointless. Restored original. Vsmith (talk) 13:30, 3 October 2013 (UTC)

How Does Half-Life Decay Stay Constant?
I know that the half-life decay for a given material is extremely consistent. My question is: How does it stay so consistent? Alternatively, how does each atom/molecule/elementary constituent particle know whether or not it ought to decay in order to keep the rate constant? Or is this simply a matter of statistics? I.e.: Each particle has a constant probability of decaying at any given moment, and since matter contains such an absurdly large number of these particles, the average number of particles decaying manages to stay wondrously constant.

I know that the article page mentions the probability idea, but I find it hard to believe that the average is so constant over time. If possible, please elaborate.

Popa910 (talk) 02:09, 19 March 2015 (UTC) If you have a good answer to this, it would be lovely to email it to me at popa910@live.com, since I probably won't be able to remember to check this. Thanks.
 * Half life stays constant, as there is not much from the outside that effects the inside of a nucleus. In the case of K-capture, it can have some dependence on outside effects on the electrons, but otherwise not much at all. Alpha decay is characterized based on tunneling out of the nucleus. Alpha particles moving at the Fermi velocity (a large fraction of c) bounce off the nuclear boundary until they manage to escape. Gah4 (talk) 02:01, 6 September 2021 (UTC)
 * Half life stays constant, as there is not much from the outside that effects the inside of a nucleus. In the case of K-capture, it can have some dependence on outside effects on the electrons, but otherwise not much at all. Alpha decay is characterized based on tunneling out of the nucleus. Alpha particles moving at the Fermi velocity (a large fraction of c) bounce off the nuclear boundary until they manage to escape. Gah4 (talk) 02:01, 6 September 2021 (UTC)

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More detail on rxn order
Maybe it should explain how to find the half-life of a nth order reaction?  Nik ol ai Ho ☎ 21:47, 10 November 2017 (UTC)

Non-exponential decay
I have boldly decided to delete the section on non-exponential decay. Some of it discusses multiple processes with different half lives, but that is covered better in the section Decay by two or more processes. Some of it is a vague made-up example about puddles. And none of it is provided with sources. It is hard to see any use for such a concept, except as evidence of a deviation from exponential decay that needs to be explained. RockMagnetist(talk) 15:37, 27 April 2018 (UTC)

 * I agree that it was mostly bad, but I'm thinking there's a core worth saving. So I just brought it back in a much much abbreviated version. Do you still dislike it? --Steve (talk) 00:54, 28 April 2018 (UTC)
 * Well, I agree with the sentiment and maybe it will protect the article against a little nonsense. It would help if you could find a citation, although I think most people don't think it needs saying. I think I'll remove the link to Rate equation because I have been working on purging the idea from there too. RockMagnetist(talk) 02:03, 28 April 2018 (UTC)
 * Apparently it's pretty common to talk about "first half life", "second half life", etc., in the context of non-exponential decay, even though I hadn't personally heard of it until now. So I put that in too. Google books gave quite a few references supporting this usage, and I just cited the first one on the list. --Steve (talk) 15:51, 28 April 2018 (UTC)
 * Yes, I found some sources that use the dependence of half-life on source concentration to determine the rate equation. Sounds pretty clunky to me, but I guess we have to follow the sources ... RockMagnetist(talk) 18:23, 28 April 2018 (UTC)

Expansion
I think this article needs expansion. Specifically, it tells us what half-lives are, how they are defined, and what concepts they are applied to, but the main problem I have is that after scanning the article, I find there is no content on the history of the term, its past definitions (if any), its etymology, or even when its usage became widespread, except for two very brief sentences, which are in the lead. I would expect an average reader to want at least some of what I am thinking, and certainly I would expect people specialized in nuclear physics or nuclear chemistry to want most—if not all—of that. What do you think? Gamingforfun 3 6 5 02:48, 9 July 2019 (UTC)

some page needed
Very sorry. Using a IP and no time do it myself now. But you know, when I search with google this article, even with the line-in-between, it gives only a screendefull of WP or al. Half-Life - the computer game. We gotta fix this :D Cheers. — Preceding unsigned comment added by 85.76.35.47 (talk) 12:35, 18 September 2019 (UTC)

Remove "Dice" Image?
I would expect the number of dice in each column to decrease with every time step. I imagine this experiment was done by re-rolling the number of dice in the preceding column, and only keeping dice that had a number below a threshold (e.g., 3, 4). Therefore the number of dice should never increase. We should remove this figure. Or explain it much better. What was the algorithm for generating the figure? If one follows the link to the page describing the experiment, they describe the algorithm correctly, stating that they remove the "1" with each subsequent roll. But in each of their data columns, the numbers are not monotonically decreasing. So I think they goofed on the experiment and the figure. I propose we delete this figure and find a better one that explains the concept. Jaredroach (talk) 16:57, 3 July 2020 (UTC)

 * Sorry about the confusion. The students brought up the dice that hit "1" at each role.  This is not half-life, but radiactivity, which also fall expenentially.  I have no opinion on whether or not the figure should be removed.--Guy vandegrift (talk) 04:18, 4 July 2020 (UTC)

Question
Is there anyway to Find the Half-Life of Something? StaleGuy22 (talk) 18:54, 17 September 2020 (UTC)
 * If you know the differential equation, then it comes directly out, after a ln(2) correction. Otherwise you measure it. Gah4 (talk) 02:03, 6 September 2021 (UTC)
 * If you know the differential equation, then it comes directly out, after a ln(2) correction. Otherwise you measure it. Gah4 (talk) 02:03, 6 September 2021 (UTC)

mean lifetime
It seems that, at least for the muon, the mean (or 1/e) life is given. In most cases that makes sense, except for some reason, maybe it is Rutherford's fault, radioactivity is commonly described using half life. It seems that we need to be either consistent, or use both (like giving units in two or more different systems). Gah4 (talk) 02:11, 6 September 2021 (UTC)

history
There is a note that the article should cover the history of half-life better. It seems to me that exponential decay was not new with radioactivity, so why the use of half-life for it, instead of the more traditional exponential decay time, otherwise known as 1/e life? Is it Rutherford? Or the Curies? In many cases, the constant is more obvious, such as RC for a discharging capacitor. The mechanism of radioactive decay isn't visible, so 1/e is less obvious, but otherwise would have been consistent. And it is sometimes used, at least for other than nuclear decay. Gah4 (talk) 11:47, 25 October 2021 (UTC)

Chemistry
Half life as a measure of the stability of a nucleus — Preceding unsigned comment added by 41.191.107.192 (talk) 18:00, 8 June 2022 (UTC)

First sentence, shouldn't the word "quantity" be followed by "of"?
I was just reading the first sentence of article. By all means if someone is an expert on linguistics and English, correct me if I am wrong. I simply feel that the word "quantity" should maybe be followed by a word, even if in brackets (with an "e.g."), like "substance" or "material". 92.238.237.65 (talk) 17:24, 26 October 2022 (UTC)

# of half-lives elapsed
At the bottom of the # of half-lives elapsed chart there is the formula 1/2n for the "fraction left" column and 100/2n for the "percentage left" column. These formulas work for number of half lives: 1 and 2, but not: 0, 3, 4, 5, and so on. For example, 1/2(3) = 1/6, but the chart says 1/8. Am I missing something, or are these 2 formulas incorrect? 104.245.77.198 (talk) 05:18, 13 December 2022 (UTC)

 * I believe the formula for the fl"fraction remaining column should be: N(t)=N0 x (1/2)^n, where N(t) is the total amount left, N0 is the beginning amount and n is the number of half-lives. The formula for percentage left would be the answer to the previous formula x 100. 104.245.77.198 (talk) 05:31, 13 December 2022 (UTC)

On mobile table appears on top before first sentence
I think it should only come after the first sentence. How could this be fixed without changing how it appears on desktop? 94.133.46.118 (talk) 19:16, 11 April 2023 (UTC)

 * @Gah4 94.133.46.118 (talk) 19:17, 11 April 2023 (UTC)
 * @Steve @Gah4 94.133.46.118 (talk) 19:18, 11 April 2023 (UTC)

Hatnote
Should we propose a hatnote, to make it less-redundant, according to this guideline.

which renders

Similar to that, the article Ghost ship was modified to make it shortened, as an example of Hatnote. --168.194.148.255 (talk) 06:00, 19 July 2023 (UTC)

title: Talk:Half-life


text:
Ponsworthy

Ponsworthy is a hamlet on the eastern side of Dartmoor, Devon, England. It lies in the steep valley of the West Webburn River about 3.5 km southwest of the village of Widecombe-in-the-Moor.

Its row of picturesque thatched cottages, climbing up a steep hill, are often the subject of calendars and postcards. It also has a mill and old bakehouse, converted to a house in 1976. Ponsworthy House, built c.1800, has a porch with Doric columns of granite. At the foot of the hill is the ‘Ponsworthy Splash’, where vehicles must drive through a small stream which runs across the road.

The village is also well known for Ponsworthy Bridge over the West Webburn River. It has a single arch and contains a stone engraved with the dates 1666 and 1792 - believed to be when repairs were carried out. It was further repaired in 1911. The bridge has a 7.5 foot width restriction, which is one of the reasons the village is so quiet, for it is impassable to modern coaches.

title: Ponsworthy


text:
Head (linguistics)

In linguistics, the head or nucleus of a phrase is the word that determines the syntactic category of that phrase. For example, the head of the noun phrase boiling hot water is the noun (head noun) water. Analogously, the head of a compound is the stem that determines the semantic category of that compound. For example, the head of the compound noun handbag is bag, since a handbag is a bag, not a hand. The other elements of the phrase or compound modify the head, and are therefore the head's dependents. Headed phrases and compounds are called endocentric, whereas exocentric ("headless") phrases and compounds (if they exist) lack a clear head. Heads are crucial to establishing the direction of branching. Head-initial phrases are right-branching, head-final phrases are left-branching, and head-medial phrases combine left- and right-branching.

Basic examples
Examine the following expressions:

 * big red dog
 * birdsong

The word dog is the head of big red dog since it determines that the phrase is a noun phrase, not an adjective phrase. Because the adjectives big and red modify this head noun, they are its dependents. Similarly, in the compound noun birdsong, the stem song is the head since it determines the basic meaning of the compound. The stem bird modifies this meaning and is therefore dependent on song. Birdsong is a kind of song, not a kind of bird. Conversely, a songbird is a type of bird since the stem bird is the head in this compound. The heads of phrases can often be identified by way of constituency tests. For instance, substituting a single word in place of the phrase big red dog requires the substitute to be a noun (or pronoun), not an adjective.

Trees
Many theories of syntax represent heads by means of tree structures. These trees tend to be organized in terms of one of two relations: either in terms of the constituency relation of phrase structure grammars or the dependency relation of dependency grammars. Both relations are illustrated with the following trees:

 * Funny stories.jpg

The constituency relation is shown on the left and the dependency relation on the right. The a-trees identify heads by way of category labels, whereas the b-trees use the words themselves as the labels. The noun stories (N) is the head over the adjective funny (A). In the constituency trees on the left, the noun projects its category status up to the mother node, so that the entire phrase is identified as a noun phrase (NP). In the dependency trees on the right, the noun projects only a single node, whereby this node dominates the one node that the adjective projects, a situation that also identifies the entirety as an NP. The constituency trees are structurally the same as their dependency counterparts, the only difference being that a different convention is used for marking heads and dependents. The conventions illustrated with these trees are just a couple of the various tools that grammarians employ to identify heads and dependents. While other conventions abound, they are usually similar to the ones illustrated here.

More trees
The four trees above show a head-final structure. The following trees illustrate head-final structures further as well as head-initial and head-medial structures. The constituency trees (= a-trees) appear on the left, and dependency trees (= b-trees) on the right. Henceforth the convention is employed where the words appear as the labels on the nodes. The next four trees are additional examples of head-final phrases:

 * Heads picture 1.jpg

The following six trees illustrate head-initial phrases:

 * Head picture 3.jpg

And the following six trees are examples of head-medial phrases:

 * Head-medial picture.jpg

The head-medial constituency trees here assume a more traditional n-ary branching analysis. Since some prominent phrase structure grammars (e.g. most work in Government and binding theory and the Minimalist Program) take all branching to be binary, these head-medial a-trees may be controversial.

X-bar trees
Trees that are based on the X-bar schema also acknowledge head-initial, head-final, and head-medial phrases, although the depiction of heads is less direct. The standard X-bar schema for English is as follows:

 * Branching7.jpg

This structure is both head-initial and head-final, which makes it head-medial in a sense. It is head-initial insofar as the head X0 precedes its complement, but it is head-final insofar as the projection X' of the head follows its specifier.

Head-initial vs. head-final languages
Some language typologists classify language syntax according to a head directionality parameter in word order, that is, whether a phrase is head-initial (= right-branching) or head-final (= left-branching), assuming that it has a fixed word order at all. English is more head-initial than head-final, as illustrated with the following dependency tree of the first sentence of Franz Kafka's The Metamorphosis:

 * Kafka English tree.jpg

The tree shows the extent to which English is primarily a head-initial language. On the broadest level, the verb phrase "discovered that he had been changed into a monstrous verminous bug" begins with the verb headword "discovered". Structure is descending as speech and processing move (visually in writing) from left to right. Most dependencies have the head preceding its dependent(s), although there are also head-final dependencies in the tree. For instance, the determiner-noun and adjective-noun dependencies are head-final as well as the subject-verb dependencies. Most other dependencies in English are, however, head-initial as the tree shows. The mixed nature of head-initial and head-final structures is common across languages. In fact purely head-initial or purely head-final languages probably do not exist, although there are some languages that approach purity in this respect, for instance Japanese.

The following tree is of the same sentence from Kafka's story. The glossing conventions are those established by Lehmann. One can easily see the extent to which Japanese is head-final:

A large majority of head-dependent orderings in Japanese are head-final. This fact is obvious in this tree, since structure is strongly ascending as speech and processing move from left to right. Thus the word order of Japanese is in a sense the opposite of English.

Head-marking vs. dependent-marking
It is also common to classify language morphology according to whether a phrase is head-marking or dependent-marking. A given dependency is head-marking, if something about the dependent influences the form of the head, and a given dependency is dependent-marking, if something about the head influences the form of the dependent.

For instance, in the English possessive case, possessive marking ('s) appears on the dependent (the possessor), whereas in Hungarian possessive marking appears on the head noun:

Prosodic head
In a prosodic unit, the head is the part that extends from the first stressed syllable up to (but not including) the tonic syllable. A high head is the stressed syllable that begins the head and is high in pitch, usually higher than the beginning pitch of the tone on the tonic syllable. For example:

The ↑bus was late.

A low head is the syllable that begins the head and is low in pitch, usually lower than the beginning pitch of the tone on the tonic syllable.

The ↓bus was late.

title: Head (linguistics)