text:
Talk:Measurement problem

Edit war
An editor, Naeemshahzada, has been repeatedly inserting a sentence into the Interpretations section
 * "It has been recently proposed that biological cells solve the measurement problem being the smallest agents capable of processing quantum information within the framework of the holographic principle, entropic gravity, and emergent dimensionality."

against a consensus of SageGreenRider, Tercer and myself. He has readded it 4 times, , , within about 3 days  --ChetvornoTALK 06:56, 14 March 2024 (UTC)

 * The problem with this addition is that it is inadequately sourced. It is supported by only two WP:primary sources, research papers by the same author, Szymon Łukaszyk.  WP requires secondary sources (WP:PSTS).  After this was pointed out, Naeemshahzada added two additional sources, also research papers by the same author, neither of which mention anything about the measurement problem, the previous papers, or the subject of the sentence.  Any relation of these papers to the topic is WP:SYNTHESIS.  In addition this sentence gives WP:UNDUE WEIGHT to a speculative theory with no support in a section that is limited to the main interpretations of quantum mechanics that have stood the test of time.

 * These are the only edits User:Naeemshahzada has made; this seems to be a WP:single use account whose goal is to insert Szymon Łukaszyk's work into Wikipedia. It seems likely that User:Naeemshahzada is Mr. Łukaszyk and he is using Wikipedia to promote his papers and his career, without the disclosure of WP:COI that Wikipedia requires.--ChetvornoTALK 17:02, 14 March 2024 (UTC)
 * I've opened (yet another) SPI: Sockpuppet_investigations/Guswen. Tercer (talk) 17:41, 14 March 2024 (UTC)
 * The first two sources, in addition to being primary, were below the standard we should adhere to. One was an item in conference proceedings, which in physics typically means no meaningful peer review, and the second was a book chapter in a collection published by a company on Beall's List. The other two were in MDPI journals, which again means that we can't expect any meaningful degree of peer review to have been applied. XOR'easter (talk) 15:23, 21 March 2024 (UTC)

 * You submit that Institute of Physics and MDPI lack credibility, while at the same time unpublished, non-peer-reviewed preprints are commonly used on Wikipedia to debase and discredit valid scientific research, even if they are plainly false.
 * For example, this non-peer-reviewed preprint is an attempt to discredit assembly theory which has been experimentally confirmed through tandem mass spectrometry, nuclear magnetic resonance, infrared spectroscopy, etc. The authors of this preprint claim, for example, (p.9), that an "object with a low assembly index (...) necessarily displays low entropy. In the opposite direction, an object with a high assembly index will (...) necessarily display high entropy". This is untrue (!). For example, two binary strings $$C=[01010101]$$ and $$D=[00010111]$$ have the same lengths $$N=8$$, Hamming weights $$N_1=N/2=4$$, and therefore the same Shannon entropies $$H(C)=H(D)=\log_2(2)=1$$ bit, but different assembly indices!
 * $$a(C)=3$$, while $$a(D)=6$$.
 * When does a fringe idea stop becoming a fringe idea? When it becomes more popular (User:Tercer), gets more support (User:Chetvorno), in particular from physical authorities (User:SageGreenRider)?
 * Will a flat Earth theory stop being a fringe idea when it becomes popular among physicists, as User:Tercer proposes?

 * And what does it mean that the main interpretations of quantum mechanics have stood the test of time? No consensus on any particular interpretation has been reached so far.

 * Perhaps life is an explanation of the measurement problem, then?

 * I am convinced it is.
 * Guswen (talk) 16:55, 21 March 2024 (UTC)

 * There are several important differences between MDPI journals versus arXiv. Journals published by the first two organizations claim to be peer-reviewed, when in fact they are not. (I have seen multiple articles in their journals that do not even appear to have been properly copyedited!) arXiv, however, has never claimed to be other than what it is: a publishing clearinghouse for non-peer-reviewed preprints, many of which subsequently are published in journals having a more rigorous review process (which becomes noted in the articles' publishing history). A second important difference is in their funding sources. MDPI journal article processing charges are generally paid for by the authors, whereas arXiv is funded by Cornell University Library, the Simons Foundation, and various member institutions. MDPI journals are hence considered to be predatory, and many academic institutions and scientific bodies actively discourage their members from publishing in those venues. Indeed, publication in such journals is often considered in a negative light in regards to academic promotion, etc. Crackpots, of course, couldn't care less. Publication in arXiv carries no negative stigma, provided that one has a decent publication history in properly peer-reviewed journals.
 * And no, although it happens, Wikipedia discourages use of arXiv as a source. Prokaryotic Caspase Homolog (talk) 12:19, 22 March 2024 (UTC)

 * I disagree.
 * G Perelman, for example, provided the solution to the Riemann hypothesis in a never-published preprint.
 * Here is a list containing examples of wikipedia relevant articles that rely on non-peer-reviewed preprints for relevant parts of the entry: -https://en.wikipedia.org/wiki/String_theory - https://en.wikipedia.org/wiki/Riemann_hypothesis -https://en.wikipedia.org/wiki/Generative_adversarial_network -https://en.wikipedia.org/wiki/Machine_learning -https://en.wikipedia.org/wiki/Modal_logic.

 * If we apply your logic, User:Chetvorno, User:XOR&, and User:Prokaryotic Caspase Homolog, Wikipedia will not have many of its most relevant articles, or they will be incomplete.

 * Guswen (talk) 13:58, 22 March 2024 (UTC)

 * You misunderstood what I wrote. First of all, Perelman did not publish in a predatory journal, but on arXiv, and his arXiv article was extensively reviewed over a several year period. Second, I did not say that citation of arXiv should be forbidden. I merely pointed out that such citations are discouraged. Sometimes there is no choice, but we editors have to use our best judgement, and ultimately the contributions have to meet consensus. Prokaryotic Caspase Homolog (talk) 15:14, 22 March 2024 (UTC)

 * That makes perfect sense to me: had Grigori Perelman published his proof of Poincaré conjecture in a predatory journal, this proof would be invalid. Guswen (talk) 21:10, 22 March 2024 (UTC)

 * XOR'easter thanks, I should have caught that. --ChetvornoTALK 17:04, 21 March 2024 (UTC)

Bohr paragraph with refs.
The current article has this paragraph:
 * Bohr offered an interpretation that is independent of a subjective observer, or measurement, or collapse; instead, an "irreversible" or effectively irreversible process causes the decay of quantum coherence which imparts the classical behavior of "observation" or "measurement".

I believe this is incorrect. I believe this is actually (at most) Rosenfeld's rationalization, not something Bohr ever said. But I don't have access to the primary ref (Bohr collected works) @ReyHahn WDYT? Johnjbarton (talk) 22:35, 30 April 2024 (UTC)
 * I got access to the book. The page referenced is a letter from Bohr to Pauli where Bohr discusses measurement. I will take a look, but I need a few days.--ReyHahn (talk) 00:02, 3 May 2024 (UTC)
 * I read Bohr to Pauli letter (16 May 1947). Bohr does discuss the role of irreversibility and microscopic dynamics but it is far from clear that it refers to measurement and observation. It mentions measurement/observation three times in the letter, once to say that Edward Teller was looking into the connections between irreversibility and observation, influenced by John von Neumann. The second time it is mentioned it says:
 * "After reconsidering the question, I feel myself that the whole question is purely epistemological and therefore of qualitative rather than quantitative character. On the one hand, it is evident that any practical observational arrangements, making use of photographic plates, cloud chambers or direct sensual impressions, involve a mechanism of amplification in the working of which free energy is spent in amounts out of all proportion with the energy exchanges characterizing the individual atomic processes under investigation. On the other hand, it is equally clear that, for the interpretation of [the] quantum mechanical formalism and the elucidation of the paradoxes involved, the problem is how to account consistently for the phenomena defined by means of measuring agencies and recording devices which serve to fix the external conditions and register the experimental results and which, for this purpose, are to be treated as ideal classical instruments."
 * the next time it is mentioned he proposes some sort of thought experiment:
 * "The irreversibility in any observational problem has its root in a certain degree of complication of the interaction of the object with the measuring agencies and, trying to make the situation more clear to me, I have considered experimental arrangements where the critical element of irreversibility may be arbitrarily far removed from the final macroscopic recording. For instance, we may, for the localization of a particle, instead of catching it directly on a photographic plate, allow it to enter through a small hole in a box from which the probability of escaping is vanishingly small and where, therefore, the presence of the particle can be ascertained in some suitable way at a later time. The degree of irreversibility here depends on the complicated character of the state of motion of the particle in the box, and the problem presents a certain analogy with the entropy increase accompanying irreversible expansion of a gas from a smaller volume v to a larger volume V which pro gas molecule is given by $$k \log V/v$$."
 * The phrase in this wiki article uses modern language that is not at all coherent with Bohr's view of old quantum mechanics. At best he says that it is an epistemological issue.--ReyHahn (talk) 11:05, 3 July 2024 (UTC)
 * @ReyHahn Excellent, thank you! I rewrote the paragraph to avoid using "quantum coherence" in connection with Bohr. That is the part that struck me as uncharacteristic. In addition his comments about amplification are good to know because this concept is used in modern quantum decoherence papers but without reference. Please review. Based on what I've read, summarizing Bohr is famously challenging. Johnjbarton (talk) 16:38, 3 July 2024 (UTC)
 * Yes that is more reliable. It would be nice to investigate what Teller said about it, but Bohr provides no reference.--ReyHahn (talk) 16:58, 3 July 2024 (UTC)

Interpretations
The "Interpretations" section is really just a repeat or summary of the interpretations. As far as I can tell the discussion and refs never cover "the measurement problem" as considered from each interpretation.

This ref covers how each interpretation deals with the measurement problem: It's not perfect because the starting point for the discussion is to assume decoherence in action. Johnjbarton (talk) 22:51, 30 April 2024 (UTC)

 * I thought the paragraph on each major interpretation did a pretty good job of relating how it explains wavefunction collapse, and isn't wavefunction collapse what the measurement problem is all about? --ChetvornoTALK 23:36, 30 April 2024 (UTC)
 * Thanks. I think your perspective clarifies to me why the section seems off to me.
 * Only some interpretations posit that "the measurement problem is about wavefunction collapse". I think the paragraphs for each interpretation should explain how "collapse" addresses the "measurement problem" directly.
 * To be sure, "wavefunction collapse" is so vaguely described that it sounds like "presto" most of the time. Thus one can easily conclude that "collapse is the solution to the measurement problem" simply because collapse can be anything one wants. Johnjbarton (talk) 01:17, 1 May 2024 (UTC)
 * Section 3, The Measurement Problem Reconsidered in
 * Bub, Jeffrey. "Why the quantum?." Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 35.2 (2004): 241-266.
 * clearly does not consider the measurement problem to be equivalent to collapse. Johnjbarton (talk) 03:12, 1 May 2024 (UTC)

 * The section is a summary of the major interpretations, written for general readers, which is the main readership of WP. To address general readers it can't include mathematics.  Given those limitations, I think it is an excellent summary.

 * You say: "I think the paragraph for each interpretation should explain how "collapse" addresses the "measurement problem" directly". I'm not sure what you mean, each paragraph does discuss collapse.  You say collapse is vaguely described: one can conclude that "collapse is the solution to the measurement problem" just because it can be anything one wants.  The section makes clear that in some interpretations like many-worlds and De Broglie-Bohm there is no collapse, and in others like some versions of Copenhagen apparent "collapse" is just updating of information.

 * I would agree that the article does not have a description of the measurement problem itself; of what the "problem of definite outcomes" is. That would include a mathematical definition of eigenstates and what "reduction of the wavefunction" is, as found in Wavefunction collapse.  And discussion of complicated stuff like preferred basis, objective vs subjective definiteness, etc.  But that does not belong in the Interpretations section.  I would suggest a separate section for that.--ChetvornoTALK 02:58, 3 May 2024 (UTC)

The cat
I recently deleted an unsourced section on Schrodinger's annoying cat. Since then I have found references for the Cat in the context of the measurement problem: So there are plenty of refs to rebuild a section with that title. Johnjbarton (talk) 22:44, 1 May 2024 (UTC)
 * Peres, Asher. "Schrödinger's immortal cat." Foundations of physics 18.1 (1988): 57-76.
 * Bell, John. "Against ‘measurement’." Physics world 3.8 (1990): 33.
 * Schlosshauer, Maximilian. "Decoherence, the measurement problem, and interpretations of quantum mechanics." Reviews of Modern physics 76.4 (2005): 1267. "A book has never been observed to be in a state of being both “here” and “there” si.e., to be in a superposition of macroscopically distinguishable positions, nor does a Schrödinger cat that is a superposition of being alive and dead bear much resemblence to reality as we perceive it."
 * Bub, Jeffrey. "Why the quantum?." Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 35.2 (2004): 241-266. "This is the measurement problem, or the problem of Schrodinger’s cat (where the cat plays the role of a macroscopic measuring instrument): it is impossible to extend the Hilbert space theory as a noncommutative mechanics to include the black box measuring instruments."

 * I have no objection to your deleting that unsourced section. But I think the article certainly should have a section on the thought experiment.  Whether or not there are any current physicists who believe that any of the interpretations could result in an alive/dead cat superposition, the experiment was historically used to discuss the measurement problem, is a great way of explaining wavefunction collapse to general readers, and today is constantly referenced in articles about the subject.  And of course today the question raised by the cat, whether a macroscopic object or system can be in a superposition, is no longer hypothetical, it has been shown to be possible.  The issue has extreme practical importance: that is what is required to create a quantum computer.  --ChetvornoTALK 19:01, 2 May 2024 (UTC)
 * Thanks. I will work on a Cat section. Johnjbarton (talk) 01:38, 3 May 2024 (UTC)
 * Ok I put something back with refs. I will add more based on other refs shortly. Johnjbarton (talk) 19:59, 6 May 2024 (UTC)
 * Looks great! --ChetvornoTALK 05:23, 8 May 2024 (UTC)

title: Talk:Measurement problem


text:
Mathesis universalis

Mathesis universalis (from μάθησις, mathesis "science or learning", and universalis "universal") is a hypothetical universal science modelled on mathematics envisaged by Descartes and Leibniz, among a number of other 16th- and 17th-century philosophers and mathematicians. For Leibniz, it would be supported by a calculus ratiocinator. John Wallis invokes the name as title in his Opera Mathematica, a textbook on arithmetic, algebra, and Cartesian geometry.

History
Descartes' most explicit description of mathesis universalis occurs in Rule Four of the Rules for the Direction of the Mind, written before 1628. Leibniz attempted to work out the possible connections between mathematical logic, algebra, infinitesimal calculus, combinatorics, and universal characteristics in an incomplete treatise titled "Mathesis Universalis" in 1695.

Predicate logic could be seen as a modern system with some of these universal qualities, at least as far as mathematics and computer science are concerned. More generally, mathesis universalis, along with perhaps François Viète's algebra, represents one of the earliest attempts to construct a formal system.

One of the perhaps most prominent critics of the idea of mathesis universalis was Ludwig Wittgenstein and his philosophy of mathematics. As Anthropologist Emily Martin notes: "Tackling mathematics, the realm of symbolic life perhaps most difficult to regard as contingent on social norms, Wittgenstein commented that people found the idea that numbers rested on conventional social understandings "unbearable"."

René Descartes
In Descartes' corpus the term mathesis universalis appears only in the Rules for the Direction of the Mind. In the discussion of Rule Four, Descartes' provides his clearest description of mathesis universalis:"; Rule Four [...] I began my investigation by inquiring what exactly is generally meant by the term 'mathematics' and why it is that, in addition to arithmetic and geometry, sciences such as astronomy, music, optics, mechanics, among others, are called branches of mathematics. [...] This made me realize that there must be a general science which explains all the points that can be raised concerning order and measure irrespective of the subject-matter, and that this science should be termed mathesis universalis — a venerable term with a well-established meaning — for it covers everything that entitles these other sciences to be called branches of mathematics. [...]"
 * We need a method if we are to investigate the truth of things.

- René Descartes, Rules for the Direction of the Mind; translated by John Cottingham

Gottfried Leibniz
In his account of mathesis universalis, Leibniz proposed a dual method of universal synthesis and analysis for the ascertaining truth, described in De Synthesi et Analysi universale seu Arte inveniendi et judicandi (1890).

Ars inveniendi
Ars inveniendi (Latin for "art of invention") is the constituent part of mathesis universalis corresponding to the method of synthesis. Leibniz also identified synthesis with the ars combinatoria, viewing it in terms of the recombination of symbols or human thoughts.

Ars judicandi
Ars judicandi (Latin for "art of judgement") is the constituent part of mathesis universalis corresponding to the method of analysis.

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

title: Mathesis universalis


text:
Tyntesfield

Tyntesfield is a Victorian Gothic Revival country house and estate near Wraxall, North Somerset, England. The house is a Grade I listed building named after the Tynte baronets, who had owned estates in the area since about 1500. The location was formerly that of a 16th-century hunting lodge, which was used as a farmhouse until the early 19th century. In the 1830s a Georgian mansion was built on the site, which was bought by English businessman William Gibbs, whose huge fortune came from guano used as fertilizer. In the 1860s Gibbs had the house significantly expanded and remodelled; a chapel was added in the 1870s. The Gibbs family owned the house until the death of Richard Gibbs in 2001.

Tyntesfield was purchased by the National Trust in June 2002, after a fundraising campaign to prevent it being sold to private interests and ensure it would be open to the public. The house was opened to visitors for the first time just 10 weeks after the acquisition, and as more rooms are restored they are added to the tour.

The mansion was visited by 356,766 people in 2019.

Background
The land on which the house and its estate were developed was originally part of the Tynte family estate. The family had lived in the area since the 1500s, but their primary residence was Halswell House in Goathurst, near Bridgwater.

By the late 1700s, John Tynte owned what is now the Tyntesfield estate; at that time the house was approached by an avenue of elm trees, planted after they were bequeathed in the 1678 will of Sir Charles Harbord to the people of Wraxall in memory of two boys he had apprenticed from the village. The Tyntes had originally lived on the estate, but by the early 1800s, John had made Chelvey Court in Brockley his principal residence. Tyntes Place was downgraded to a farmhouse and leased to John Vowles. In 1813, George Penrose Seymour of the adjoining Belmont estate purchased the property and gave it to his son, the Rev. George Turner Seymour. He in turn built a new Georgian mansion on the site of the former Saddler's Tenement, and demolished the old farmhouse. Further remodelling was undertaken by Robert Newton of Nailsea.

Purchase by the Gibbs family
In 1843, the property was bought by businessman William Gibbs, who made his fortune in the family business, Antony Gibbs & Sons. From 1847 the firm had an effective monopoly in the import and marketing to Europe and North America of guano from Peru as a fertilizer. This was mined by indentured Chinese labour on the Chincha Islands in conditions which the Peruvian government acknowledged in 1856 had degenerated "into a kind of Negro slave trade". The firm's profits from this trade were such that William Gibbs became the richest non-noble man in England.

Throughout his life, William Gibbs and his wife Matilda Blanche Crawley-Boevey (known as Blanche), principally lived in London, for the greater part of his marriage at 16 Hyde Park Gardens, which the family owned until Blanche's death. But as he travelled regularly on business to the Port of Bristol he required a residence in the area; thus it was, in 1843, he came to buy Tyntes Place, which he subsequently renamed Tyntesfield. Within a few years of making his purchase, Gibbs began a major program of rebuilding and enlarging of the mansion.

The architectural style selected for the rebuilding was a loose Gothic combining many forms and reinventions of the medieval style. The choice of Gothic was influenced by William and Blanche Gibb's Anglo-Catholic beliefs as a followers of the Oxford Movement. This wing of the Anglican Church advocated the view set out in the architect Augustus Pugin's 1836 book Contrasts, which argued for the revival of the medieval Gothic style, and "a return to the faith and the social structures of the Middle Ages". The Oxford Movement, of which both Pugin and Gibbs were disciples, later took this philosophy a step further and claimed that the Gothic style was the only architecture suitable for Christian worship. Thus it became a symbolic display of Christian beliefs and lifestyle, and was embraced by devout Victorians such as Gibbs. The completion of the mansion's chapel further accentuated the building's medieval monastical air so beloved by the Oxford Movement's devotees. When completed, the ecclesiastical design was reinforced by a dominating square tower with a steeply pitched roof adorned by four tourelles, which was demolished in 1935.

Redevelopment

In 1854 William Gibbs commissioned John Gregory Crace, an architect he was already using elsewhere, to redesign and decorate the principal rooms at Tyntesfield. These new designs included gilded panelling, woodwork, moulding and chimneypieces all in the Gothic style.

Rebuilding work did not begin in earnest until 1863, when William Gibbs had the property substantially remodelled in a Gothic Revival style. William Cubitt & Co. were the builders and John Norton was the architect. Norton's design enveloped the original house. He added an extra floor, two new wings and towers. Norton emphasised the importance of architectural continuity in restoration and rebuilding relating to several historical periods. As a result, while some walls remained plain, others were adorned with Gothic and naturalistic carvings to fit in with the previous architectural styles.

Design
The house is built of two types of Bath Stone, and is highly picturesque, bristling with turrets and possessing an elaborate roof. The combined effect of the architecture and chosen materials has been described by journalist Sir Simon Jenkins as "severe". During restoration, stonemasons either conserved or, on occasion, copy-carving new sections, carving new mouldings to replace standard architectural elements that formed the weathering, as well repointing most of the miles of lime pointing. All stone was accurately matched to the original, with Veyzeys quarry near Tetbury providing Cotswold oolitic limestone. The house, which includes the servants' wing and the chapel, was made a Grade II*listed building in 1973, and has since been upgraded to Grade I.

The front (facing east over the gardens towards Backwell Hill) and north (entrance courtyard) are faced in one shade of ochreous Bath Stone, while the south (rear), which is mainly allocated to the service area and servants quarters, is faced in cheaper red-tinged Draycott marble rubble, and has some plastered finishes. All facades have many Gothic main windows, Tudor oriel windows, chimneys and attic dormers. Norton topped the design with an irregular roof, its various pitches and gables emphasising the building's asymmetrical architecture. The final external addition was a huge ironwork conservatory by Hart, Son, Peard and Co. to the rear. The result was described by novelist Charlotte Mary Yonge, a cousin of Blanche Gibbs, as "like a church in spirit".

The interiors were also in the Gothic style. Crace was again engaged to remodel the interiors, in some places extending or adapting his initial works, in others providing new schemes. Other notable features of the house are glass by Powell and Wooldridge, ironwork by Hart, Son, Peard and Co. and mosaics by Salviati. George Plucknett was Cubitt's foreman, who was related to James Plunkett of Collier and Plucknett, furniture makers of Warwick. The result was that Gibbs ordered a number of specially commissioned pieces from the firm, including a fully fitted bathroom for his wife. All of these fine pieces of craftsmanship were added to by Gibb's expanding collection of artworks.

While the reconstruction on the house was being undertaken, William Gibbs had rented Mamhead Park in Devon. The total cost of redevelopment to create a house with 23 main bedrooms and 47 in total including servants' accommodation came to £70,000 (equivalent to £0 in ). The sum was equivalent to 18 months gross profit from all of Gibbs's business interests. After completion of the main building works, Gibbs created more cash by selling shares in Antony Gibbs & Sons to his nephew Henry Hucks Gibbs (later Lord Aldenham), which enabled him to purchase two adjoining properties – including Belmont to the east from his nephew George Lewis Monck Gibbs – to create a farming estate, founded on dairy production and forestry management. Added to further by later land purchases, at its peak the Tyntesfield estate spanned over 6000 acre, encompassing 1000 acre of forest, from Portishead in the north to south of the valley in which the main house lay. The house and estate employed more than 500 workers.

Chapel
Gibbs' final addition to Tyntesfield was added between 1872 and 1877, when he commissioned Arthur Blomfield to add a Gothic chapel to the north side of the house. Modelled on the Sainte-Chapelle in Paris, it housed an organ by William Hill & Sons, and below a vault in which Gibbs intended to be buried. However, combined opposition from both the vicar of the local All Saints Church, Wraxall and the church's patron, a member of the Gorges family, led to the Bishop of Bath and Wells decreeing that he would not sanction the consecration of Tyntesfield's chapel, through fears that it would take power away from the local population fully into Gibb's hands. Despite this, the chapel formed a central part of life at Tyntesfield, and prayers were said twice-daily by the family and their guests. Throughout their period of residence, the family would also open the chapel to local people on an annual basis, often during Rogation days and at Christmas. In praise of the resultant final building, Yonge described the chapel as the final completion of the Tyntesfield project, providing "a character to the household almost resembling that of Little Gidding". The Little Gidding community in Huntingdonshire was much idealized by 19th-century Anglo-Catholics.

William Gibbs: 1846–75
Seven children were born to William and Matilda. All were devout Anglicans, with William and his wife being supporters of the Oxford Movement. He was a major benefactor of Keble College, Oxford, and dedicated the later part of his life to philanthropic works. Also being teetotal, he added to the estate's holding by buying the local Failand Inn, which enabled him to control any riotous behaviour (it was sold to Courage Brewery in 1962 by the second Lord Wraxall). William Gibbs died in the house on 3 April 1875. After a service at the estate chapel on 9 April, 30 estate workers carried his coffin to All Saints Church, Wraxall. He is buried within the family plot in the church grounds.

Antony Gibbs:1875–1907
The estate then passed to William's eldest son Antony. After graduating with a Master of Arts degree from Exeter College, Oxford, he joined the North Somerset Yeomanry where he attained the rank of Major. He married Janet Louisa Merivale on 22 June 1872, and returned to Tyntesfield to manage the family estate. Antony held various positions of authority, including Justice of the Peace and later Deputy Lieutenant of Somerset. The couple had 10 children.

During the 1880s, Antony had Henry Woodyer redesign the hallway staircase. This allowed more light to permeate the lower floors from the glazed lantern roof, and hence turn the hallway into a reception room. Woodyer also extended the Dining Room by taking in part of the original housekeeper's room. Crace's original wallpaper – a British imitation of Japanese paper, that itself imitated Spanish tooled leather – was lightened by a 14-year-old apprentice who hand-painted in a cream background. The sideboard, which had been commissioned from Collier and Plucknett, was further extended. New items were also ordered from Collier and Plucknett. Simultaneously, Antony had electricity installed, an early UK example of houses being lit in this way. Antony spent the first night after turning on the electrical system watching the main entrance light, to ensure that it did not create a fire and was hence safe for his family. At some point between 1868 and 1884 a water hydraulic lift was installed by Waygood and Co., the remains of which were discovered in 2008. A wooden lift car was discovered on the ground floor and a 55 inch spanning sheave in the roof space.

George Abraham Gibbs, 1st Baron Wraxall: 1907–31
George Abraham Gibbs, 1st Baron Wraxall served as a colonel in the North Somerset Yeomanry and served in the Boer War campaign. On his return to England he married the Hon. Victoria Florence de Burgh Long; the couple moved to Clyst St George in Devon. Between 1918 and 1928, he served as MP for Bristol West and was elevated to the peerage as Baron Wraxall in 1928, for which his appointment as Treasurer of the Household had been instrumental.

Under his ownership, the Drawing Room was redecorated in a Renaissance Venetian style, In the process, Crace's stencilling was over painted and then covered by damasked silk, the Norton fireplace was removed, the furniture replaced with Edwardian pieces, and the carpet dyed by Sketchleys. In 1917, to assist the war effort, the ironwork conservatory was razed, and its ironwork melted down for ammunition.

Survived by a daughter, Albina, George's first wife died at Tyntesfield from influenza in 1920. In 1927, George married Ursula Mary Lawley, a daughter of Sir Arthur Lawley (later the 6th and last Baron Wenlock). The couple had two sons, George (known as Richard) and Eustace. George died at Tyntesfield on 28 October 1931, aged 58.

Ursula, Lady Wraxall: 1931–79
Lord Wraxall's widow, Ursula, Lady Wraxall, was left with two children under two years of age, little income, and a large estate. Noted for her efficiency and practicality, when the clock tower, the focal point of the house, needed substantial repairs in 1935 to overcome dry and wet rot, she simply had it disassembled, stored the metal parts for possible later usage and realigned the roof as if the clock tower had never existed.

During the Second World War, Clifton High School was relocated to the property, and in 1941 the U.S. Army Medical Corps established a facility for wounded soldiers, known as the 74th General Hospital, in the estate grounds. The construction of this temporary tented village resulted in the US Army Engineers breaching what was then England's longest holly hedge. With many tents later replaced by prefabricated buildings and some nissen huts, at one point in the war following D-Day it became the largest US Army hospital in Europe. During the hostilities, management of the estate's farmland was assumed by the Ministry of Agriculture (MoA), leaving Lady Wraxall only the Home Farm.

Bombs often landed on the estate during the blitz of Bristol. In September 1940, during a raid on the Bristol Aeroplane Company factory at Filton, bombs cut off the estate's water supply, and during a later raid, one bomb badly damaged the lantern roof light over the hallway. In 1946, after the end of the war, Lady Wraxall applied to the Ministry of Defence for a repair grant, but was turned down. As a result, damp, and latterly birds, entered the house through the roof light, until the house came into the ownership of the National Trust and was repaired.

Richard Gibbs, 2nd Baron Wraxall: 1979–2001
George Richard Lawley Gibbs, known as Richard, was born on 16 May 1928, and was educated at Eton College and Sandhurst. He spent eight years with the Coldstream Guards. He never married and was succeeded by his brother, Sir Eustace Gibbs, a diplomat, who became the third Baron Wraxall.

Richard died unmarried in 2001 from complications arising from an asthma attack, having reduced his usage of the substantial accommodation within Tyntesfield to just three rooms.

National Trust purchase
Concerned with the demolition and desecration of various historic country houses since the end of the Second World War – 450 great houses were completely demolished in England between 1945 and 1955 – in the 1970s the National Trust commissioned architect Mark Girouard to catalogue and assess the remaining Victorian country houses across the United Kingdom for significance and structural integrity. He published his findings in a report, and later in the book The Victorian Country House, which in the revised second edition of 1976 included Tyntesfield as allowing access. With the Trust as a result placing Tyntesfield second on its list of priorities for preservation, Girouard said of the property: "There is no other Victorian country house which so richly represents its age as Tyntesfield."

In his later life, Richard Gibbs recognised that the diverse interests of the large family, and the need to invest heavily in even basic refurbishment of the house to make it weather-secured and habitable, would require the family to sell Tyntesfield. Recognising also that substantial death duties would become payable on his death, Richard drew up a will based around a trust that would allow his fortune to pass to the surviving children of his brother and half sister, a total of 19 beneficiaries.

When Richard died, the trust he had set up stated that, should the trustees agree by majority that the estate should be sold, such a sale should be completed within 12 months, and to the highest bidder. The house and estate of 1000 acre of farmland, 650 acre of woodlands, plus 30 houses and cottages, were listed for sale by Savills in three main lots (total estimated at £15 million); with Christie's contracted to secure the sale of the house and estate contents via a separate auction (total estimated at a further £15 million).

Having not bought a country house since the 1991 purchase of Chastleton House, which took seven years to open to the public, and competing with no special status amongst the bidders, the rumoured competitors to the Trust were listed by the media to have included composer Lord Andrew Lloyd Webber, and pop stars Madonna and Kylie Minogue. However, the new Director-General of the National Trust, Fiona Reynolds, launched a £35 million appeal in May 2002 via the "Save Tyntesfield" campaign, with support from designer Laurence Llewelyn-Bowen, newsreader Jon Snow and several top architects and historians. The Trust's appeal collected £8.2 million in just 100 days, with: £3 million+ from the public; and two substantial anonymous donations of £1 million and £4 million. The Trust also received funding from the National Heritage Memorial Fund, totaling £17.4 million after negotiations with its chair, Liz Forgan, its largest single grant ever which caused some controversy. The National Lottery has earmarked a further £25 million for the major conservation work that is needed.

As a result of the auction, the former "Tyntesfield Estate" no longer exists. The National Trust purchased only the main central part of the Estate which comprises the house, the kitchen garden, and the park. The trust also sold off additional lands. The resultant preserved house and surrounding gardens sat on a total of 150 acre of land are now simply known as Tyntesfield. Charlton Farm, is now home to Children's Hospice South West, which provides palliative care to children with terminal illnesses. Charlton House was sold into private hands, having been since 1927 the home of the Downs School.

Initial conservation
After taking ownership in 2002, National Trust staff secured the house and gardens, preserving them and the contents, and then catalogued the contents of the house which had been collected by the four generations of the family. Starting out with a staff of 30 volunteers, by 2013 the total of employed and volunteer staff exceeded 600, more than the number engaged by any other National Trust property.

The initial conservation work focused around weatherproofing the house. The repair of the roof, which is 20 times the size of the average British family's home, was made possible by the erection of an extensive free-standing scaffold roof structure. At the height of the restoration works, 28 mi of scaffolding tubes covered the building's entire exterior. This allowed repairs and restoration to take place over 18 months, including the final restoration of the original bold red and black tiled geometric diaper pattern. The entire property was rewired with special cabling, copper sheathed (fire and rodent proofed). Much of the original lead piping was replaced and a fireproofing scheme, mainly through the design of a suitable compartmentation system was designed and implemented. Interior scaffolding was installed in the 43 ft high hallway to repair the lantern rooflight, and to provide access to other high points of the interior. These initial works cost more than £10 million, much of which was raised through donations via the "Save Tyntesfield" campaign and the sale of lottery tickets to visitors.

The Trust had been reluctant to allow visitors to the house while work was underway, especially taking into account the costs of Health and Safety requirements and the delays these could cause to the essential preservation works. But the need for cash dictated the answer, and the Trust learnt that, through giving the public close access to the preservation works, they actually gave more additional donations as a result of seeing where their money was going and how they were making a difference.

House interior
Principal rooms include the Library, Drawing Room, Billiard Room, Dining Room and Chapel. During restoration, the National Trust, for the first time, allowed visitors to become involved in the restoration process and "witness the challenge of bringing Tyntesfield back to life."

The Library is regarded as the most important gentleman's library in the possession of the Trust. The carpet and some of the furnishings in the Library were designed by Crace, whilst the book collection is the most extensive Victorian library collection owned by the Trust.

The centre of the house is occupied by the hallway and staircase, which show the greatest number of changes since the original design.

Once the Trust took ownership, scaffolding was placed in the hallway to repair the roof lantern. While this was in place the architectural paint analyst Lisa Oestreicher was able to examine the decorative scheme that had been used in the spaces and room frequented by the public. Three principal phases were identified: 1860s original; 1870s updates and adaptions; 1887–90 redecoration, which returned the main spaces to the original green colours and motifs created by Crace. Once lantern repairs were complete, the Trust replaced the elderly chenille carpet destroyed by contractors working for Christie's with a new Wilton carpet with a replica design by Linney Cooper, bought with £45,000 from public lottery donations.

Contents
Christie's originally estimated the house contents at in excess of 10,000 items, but by 2008 a total of 30,000 items had been listed including: William Butterfield designed silver; original print books by Pugin and Ruskin; an unexploded Second World War bomb; a jewel-encrusted chalice; a roll of 19th-century flock wallpaper; and a coconut with carved face and hair. By 2013 the inventory had risen to 47,154 items, with still more rooms to unpack and catalog.

Paintings
Many of the family's extensive collection of paintings, most sourced from Spain by William, were donated to the Trust. In part this was due to their poor condition, which involved not just water but also ironically guano damage. The most important painting in the collection is the 17th-century work by Zambrano of St Lawrence, which hangs in the middle of one of the walls of the hall. It was cleaned and repaired by local art conservators Bush and Berry, who are based in a chapel William Gibbs built in the village of Flax Bourton. In 2011 the Trust bought the painting The Mater Dolorosa (Mother of Sorrows) by Bartolomé Esteban Murillo at Christie's auction in New York, which had hung at Tyntesfield since William purchased it until some time after 1910.

Home Farm Visitor Centre
The Home Farm buildings were built in the 1880s, split over two levels. To the south is a two-storey covered yard with a timber roof structure, used for the rearing of farm animals. On the upper level is the main yard, where to the east and west are two wings, one side of which housed the former piggery. The farm offices make up the north wing, to fully enclose the square but gently south-sloping yard.

The Grade II*listed buildings needed full renovation, which took a secondary priority in the Trust's plans after the house. The Trust have converted the buildings into an integrated and self-contained visitor centre, which opened in mid-2011 with:
 * Upper yard:
 * Demonstration area: country crafts from visiting crafts people
 * Plant centre: excess plants raised by the gardeners are sold to raise funds
 * Farm-themed play area
 * Secondhand books stall: proceeds from which raise funds for the Trust
 * Restaurant: the former two-story covered yard has been fully renovated and converted into a cafe/restaurant; it also houses the gift shop. A new-build staircase, lift and bridge walkway all in steel provide access from the upper yard
 * A separate building to the east provides power and heat to the visitor centre, using a combination of solar thermal panels, photovoltaic cells and a biomass boiler.

Park
The house sits within 150 acre of parkland, which the Trust gained from the auction and retained around the property to preserve the house within its environment. The wooded park leads down a tree-lined drive to balustraded terraces, and paths lead to the rose garden, summer houses, the aviary and the former concrete-lined lake, which has been empty since the Second World War.

From the latter part of the nineteenth century onwards, William Gibbs and descendants added interesting specimens to the existing trees in the two areas of parkland to the South and West of the house and gardens. The estate now has fourteen Champion Trees on The National Tree Register.

A five year project by the National Trust, underway in 2022, to conserve ancient, veteran and notable trees, in a number of sites across Bristol, included Tyntesfield. The Tyntesfield site is of additional national significance because its many ancient and veteran trees support populations of rare, vulnerable and endangered invertebrates.

Kitchen garden
The kitchen garden includes glasshouses and frames, the large classical Orangery and quarters for the gardeners.

Orangery
The Grade II*listed Orangery was once the architectural focal point of the kitchen garden complex. But when the Trust bought the property, the Orangery was in such a precarious state of deterioration that it was on English Heritage's Heritage at Risk Register in the highest priority category, A.

Built in 1897, it is a rare surviving example of a late Victorian orangery in the Classical style, constructed from ashlar and red brick. It has a seven-bay east/west plan with central entrances and three bays north–south, topped by a fully glazed ironwork hipped-roof. An entablature with protruding horizontal geison sits above Ionic half-column supports and corner pilasters. The centre entrance bay on the west front towards the kitchen garden breaks forward as a portico, with pairs of giant engaged columns and broken pediment with a small oculus. Between each pair of columns are large round-headed windows with Gibbs surrounds and keystones.

To preserve and restore the Orangery, the Trust teamed-up with City of Bath College and Nimbus Conservation Ltd in an innovative partnership, whereby 12 trainee stonemasons worked alongside professional craftsmen to hone their skills and carry out the specialist stonework needed. The Trust also introduced workshops for other restoration professionals, academics and eventually opened them to interested members of the public, where all were educated in a hands-on environment in the skills required to repair the building. For this crafts-based training initiative, in 2011 the Trust won a Daily Telegraph sponsored English Heritage Angel Award.

The budget for the works was £420,000, with initial work focused on stabilising the foundations and lower masonry. Much of this was achieved through the injection of stabilising materials into the foundations, which needed time to cure and solidify. Works then progressed to the walls and roof, and finally the decorative embellishments. Today, while part of the Orangery is a dedicated café, the rest is used for training new craftsmen and restoration specialists.

Aviary
The aviary at Tyntesfield is situated to the west of the house, adjacent to the footings of the old conservatory. It was built in 1880 to house exotic birds, but was converted into a playhouse for Doreen, the first Lord Wraxall's daughter. The aviary is considered one of the most distinctive features of the estate, and is Grade II listed.

Sawmill
Located on a site originally occupied by a foreman's office when the land was used for quarrying, the new sawmill building was completed in 1899, providing electricity via two enclosed steam engines and pneumatic power across the estate. The engines were housed in what is now called the Engine Room, while the Lantern Room held multiple lead acid batteries. After opening, the decision was made to relocate the estate's entire sawmill to the building, to enable better access to electrical power. The steam engines were replaced by diesel generators, and electricity was provided from the national grid post-WW2. In the 1960s, the sawmill was decommissioned and all wood sold to third party contractors to be converted into sawn wood products.

Under the Trust's ownership the sawmill has been renovated and converted into a combined learning, educational and rentable function space for businesses and members of the public. It is most often used by National Trust staff and volunteers to educate visiting school groups. The building now houses the biomass boiler for the main house, which saves 141 tonnes of CO2 a year over the old oil-fired boiler. Another section of the former wood shed was used as a new roost site for bat species, creating a "bat palace". The centre was opened in May 2009 by Dame Jenny Abramsky, Chair of the Heritage Lottery Fund, who partially funded the works.

Bats
Ten of the seventeen species of UK bat are found on the property, eight within the structure of the house alone. Species found include the rare and threatened lesser horseshoe bat and greater horseshoe bat. Maintenance work is timed to fit in with hibernating and mating schedules, and new roosts are created during any building work. Visitors may see some of the property's bats on a closed-circuit television system.

Visitor access
Visitor access to Tyntesfield is via the B3128 road. The nearest train station is 2 mi away at Nailsea and Backwell. Bus services are available from Bristol. Entry to the house is via timed ticket in 30-minute entry blocks. The grounds include six geocaching trails.

In popular culture
In 2002, after its purchase by the National Trust but before its opening to the public, the house and its contents were explored in the Oxford Films documentary, The Lost World of Tyntesfield, hosted by art historian Dan Cruickshank. The house was featured in the 2017 film Crooked House, an adaptation of the Agatha Christie novel of the same name starring Glenn Close, Terence Stamp, Max Irons and Christina Hendricks. It also featured in the BBC television series Sherlock in the episode "The Abominable Bride" and Doctor Who in the episode "Hide".

title: Tyntesfield


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User:Rune~enwiki

Rune stone

I have contributed on the Slalom and Sail article.

title: User:Rune~enwiki


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Window manager

A window manager is system software that controls the placement and appearance of windows within a windowing system in a graphical user interface. Most window managers are designed to help provide a desktop environment. They work in conjunction with the underlying graphical system that provides required functionality—support for graphics hardware, pointing devices, and a keyboard—and are often written and created using a widget toolkit.

Few window managers are designed with a clear distinction between the windowing system and the window manager. Every graphical user interface based on a windows metaphor has some form of window management. In practice, the elements of this functionality vary greatly. Elements usually associated with window managers allow the user to open, close, minimize, maximize, move, resize, and keep track of running windows, including window decorators. Many window managers also come with various utilities and features such as task bars, program launchers, docks to facilitate halving or quartering windows on screen, workspaces for grouping windows, desktop icons, wallpaper, an ability to keep select windows in foreground, the ability to "roll up" windows to show only their title bars, to cascade windows, to stack windows into a grid, to group windows of the same program in the task bar in order to save space, and optional multi-row taskbars.

History
In 1973, the Xerox Alto became the first computer shipped with a working WIMP GUI. It used a stacking window manager that allowed overlapping windows. However, this was so far ahead of its time that its design paradigm would not become widely adopted until more than a decade later. While it is unclear if Microsoft Windows contains designs copied from Apple's classic Mac OS, it is clear that neither was the first to produce a GUI using stacking windows. In the early 1980s, the Xerox Star, successor to the Alto, used tiling for most main application windows, and used overlapping only for dialogue boxes, removing most of the need for stacking.

The classic Mac OS was one of the earliest commercially successful examples of a GUI that used a sort of stacking window management via QuickDraw. Its successor, macOS, uses a somewhat more advanced window manager that has supported compositing since Mac OS X 10.0, and was updated in Mac OS X 10.2 to support hardware accelerated compositing via the Quartz Compositor.

GEM 1.1, from Digital Research, was a operating environment that included a stacking window manager, allowing all windows to overlap. It was released in the early 1980s. GEM is famous for having been included as the main GUI used on the Atari ST, which ran Atari TOS, and was also a popular GUI for MS-DOS prior to the widespread use of Microsoft Windows. As a result of a lawsuit by Apple, Digital Research was forced to remove the stacking capabilities in GEM 2.0, making its window manager a tiling window manager.

During the mid-1980s, Amiga OS contained an early example of a compositing window manager called Intuition (one of the low-level libraries of AmigaOS, which was present in Amiga system ROMs), capable of recognizing which windows or portions of them were covered, and which windows were in the foreground and fully visible, so it could draw only parts of the screen that required refresh. Additionally, Intuition supported compositing. Applications could first request a region of memory outside the current display region for use as bitmap. The Amiga windowing system would then use a series of bit blits using the system's hardware blitter to build a composite of these applications' bitmaps, along with buttons and sliders, in display memory, without requiring these applications to redraw any of their bitmaps.

In 1988, Presentation Manager became the default shell in OS/2, which, in its first version, only used a command line interface (CLI). IBM and Microsoft designed OS/2 as a successor to DOS and Windows for DOS. After the success of Windows 3.10, however, Microsoft abandoned the project in favor of Windows. After that, the Microsoft project for a future OS/2 version 3 became Windows NT, and IBM made a complete redesign of the shell of OS/2, substituting the Presentation Manager of OS/2 1.x for the object-oriented Workplace Shell that made its debut in OS/2 2.0.

X window managers
On systems using the X window system, there is a clear distinction between the window manager and the windowing system. Strictly speaking, an X window manager does not directly interact with video hardware, mice, or keyboards – that is the responsibility of the display server.

Users of the X Window System have the ability to easily use many different window managers – Metacity, used in GNOME 2, and KWin, used in KDE Plasma Workspaces, and many others. Since many window managers are modular, people can use others, such as Compiz (a 3D compositing window manager), which replaces the window manager. Sawfish and awesome on the other hand are extensible window managers offering exacting window control. Components of different window managers can even be mixed and matched; for example, the window decorations from KWin can be used with the desktop and dock components of GNOME.

X window managers also have the ability to re-parent applications, meaning that, while initially all applications are adopted by the root window (essentially the whole screen), an application started within the root window can be adopted by (i.e., put inside of) another window. Window managers under the X window system adopt applications from the root window and re-parent them to apply window decorations (for example, adding a title bar). Re-parenting can also be used to add the contents of one window to another. For example, a flash player application can be re-parented to a browser window, and can appear to the user as supposedly being part of that program. Re-parenting window managers can therefore arrange one or more programs within the same window, and can easily combine tiling and stacking in various ways.

Microsoft Windows
Microsoft Windows has provided an integrated stacking window manager since Windows 2.0; Windows Vista introduced the compositing Desktop Window Manager (dwm.exe) as an optional hardware-accelerated alternative. In Windows, since GDI is part of the kernel, the role of the window manager is tightly coupled with the kernel's graphical subsystems and is largely non-replaceable, although third-party utilities can be used to simulate a tiling window manager on top of such systems. Since Windows 8, the Direct3D-based Desktop Window Manager can no longer be disabled. It can only be restarted with the hotkey combination Ctrl+Shift+Win+B.

Windows Explorer (explorer.exe) is used by default as the shell in modern Windows systems to provide a taskbar and file manager, along with many functions of a window manager; aspects of Windows can be modified through the provided configuration utilities, modifying the Windows Registry or with 3rd party tools, such as WindowBlinds or Resource Hacker.

A complete X Windows Server, allowing the use of window managers ported from the unixoid world can also be provided for Microsoft Windows through Cygwin/X even in multiwindow mode (and by other X Window System implementations). Thereby, it is easily possible to e.g. have X Window System client programs running either in the same Cygwin environment on the same machine, or on a Linux, BSD Unix etc. system via the network, and only their GUI being displayed and usable on top of the Microsoft Windows environment.

Note that Microsoft and X Window System use different terms to describe similar concepts. For example, there is rarely any mention of the term window manager by Microsoft because it is integrated and non-replaceable, and distinct from the shell. The Windows Shell is analogous to the desktop environment concept in other graphical user interface systems.

ChromeOS
Since 2021 ChromeOS is shipped with its own window manager called Ash. Chromium and ash share common codebase. In the past one could run it by using google-chrome --open-ash on any compatible systems.

Types
Window managers are often divided into three or more classes, which describe how windows are drawn and updated.

Compositing window managers
Compositing window managers let all windows be created and drawn separately and then put together and displayed in various 2D and 3D environments. The most advanced compositing window managers allow for a great deal of variety in interface look and feel, and for the presence of advanced 2D and 3D visual effects.

Stacking window managers
All window managers that have overlapping windows and are not compositing window managers are stacking window managers, although it is possible that not all use the same methods. Stacking window managers allow windows to overlap by drawing background windows first, which is referred to as the painter's algorithm. Changes sometimes require that all windows be re-stacked or repainted, which usually involves redrawing every window. However, to bring a background window to the front usually only requires that one window be redrawn, since background windows may have bits of other windows painted over them, effectively erasing the areas that are covered.

Tiling window manager
Tiling window managers paint all windows on-screen by placing them side by side or above and below each other, so that no window ever covers another. Microsoft Windows 1.0 used tiling, and a variety of tiling window managers for X are available, such as i3, awesome, and dwm.

Dynamic window manager
Dynamic window managers can dynamically switch between tiling or floating window layout. A variety of dynamic window managers for X are available.

Features and facilities of window managers

 * Autohide
 * An autohide facility enables menubars to disappear when the pointer is moved away from the edge of the screen.

 * Borders
 * A border is a window decoration component provided by some window managers, that appears around the active window. Some window managers may also display a border around background windows.

 * Context Menu
 * Some window managers provide a context menu that appears when an alternative click event is applied to a desktop component.

 * Desktop Wallpaper
 * Some window managers provide a desktop wallpaper facility that displays a background picture in the root window.

 * Focus Stealing
 * Focus stealing is a facility some window managers provide. It allows an application not in focus to suddenly gain focus and steal user input intended for the previously focused application.

 * Iconification
 * An iconification facility lets users minimize running applications to a desktop icon or taskpanel icon.

 * Joined Windows
 * Some window managers provide a joined windows facility that lets user join application window frames together.

 * Keyboard Equivalents
 * Some window managers provide keyboard equivalents that enables the keyboard to replicate mouse functionality.

 * Menubar
 * A menubar provides the facility to launch programs via a menu and may contain additional facilities including a start button, a taskbar, and a system tray.

 * Menu Panel
 * A menu panel a component of some window managers that provides the facility to launch programs using a menu. A menu panel is similar to a menubar, but appears as a floating panel, rather than a horizontal or vertical bar.
 * The menu panel may contain additional facilities including a start button, a task panel, and a system tray.

 * Mouse focus
 * The mouse focus model determines how the pointing device affects the input focus within the window manager. The focus model determine which component of the graphical user interface is currently selected to receive input as the pointer is moved around the screen.

 * Mouse warping
 * Mouse warping is a facility that centres the pointer on the current application as it is made active.

 * Multiple Desktops
 * A window manager may provide a multiple desktops facility. This enables switching between several root window desktops. This prevents clutter of the root window, because applications can run on different desktops.

 * Pager
 * Some window managers provide a pager tool that provides the facility to switch between multiple desktops. The pager may appear as an onscreen window or as a gadget in the taskbar or taskpanel.

 * Plugins
 * Some window managers have a modular construction that enables plug-in modules to provide features as required.

 * Rollup
 * A rollup facility enables windows to appear as just a titlebar on the desktop.

 * Root Menu
 * Some window managers provide a root menu, which appears when the root window or desktop background is touched.

 * Shortcuts
 * Some window managers provide a shortcut facility that lets users place icons on the root window that access specific programs or facilities.

 * Tabbed Windows
 * Some window managers provide a tabbed windows facility that groups applications together in common frames.

 * Task Switching
 * The window manager may provide various task switching facilities that let the user change the currently focused application, including:

 * Changing the mouse focus using a pointing device
 * Keyboard task switching facilities (for example, by pressing Alt-Tab)
 * Clicking on the task in a taskbar or taskpanel

 * Taskbar
 * Some window managers provide a taskbar that shows running applications. The taskbar may show all applications that are running including those that have been minimized, and may provide the facility to switch focus between them. The taskbar may be incorporated into a menubar on some window managers.

 * Task Panel
 * A task panel is similar to a taskbar, but appears as a floating panel, rather than a horizontal or vertical bar.

 * Start Button
 * A start button is a desktop widget that provides a menu of programs that can be launched. The start button is typically placed on a menubar at the bottom of the screen.

 * Notification Area
 * A Notification Area is used to display icons for system and program features that have no desktop window. It contains mainly icons to indicate status information and notifications such as arrival of a new mail message. Some systems may also show a clock in the Notification Area.

 * Title Bars
 * A titlebar is a window decoration component some window managers provide at the top of each window. The titlebar is typically used to display the name of the application, or the name of the open document, and may provide title bar buttons for minimizing, maximizing, closing or rolling up of application windows.

 * Title Bar Buttons
 * Title bar buttons are included in the titlebar of some window managers, and provide the facility to minimize, maximize, rollup or close application windows. Some window managers may display the titlebar buttons in the taskbar or task panel, rather than in a titlebar.

 * Virtual Desktop
 * A virtual desktop (also called a scrolling desktop) is a facility some window managers provided that lets the desktop be larger than the actual screen

Windows navigation
An active window is the currently focused window in the current window manager. Different window managers indicate the currently-active window in different ways and allow the user to switch between windows in different ways. For example, in Microsoft Windows, if both Notepad and Microsoft Paint are open, clicking in the Notepad window will cause that window to become active. In Windows, the active window is indicated by having a different colored title bar. Clicking is not the only way of selecting an active window, however: some window managers (such as FVWM) make the window under the mouse pointer active—simply moving the mouse is sufficient to switch windows; a click is not needed.

Window managers often provide a way to select the active window using the keyboard as an alternative to the mouse. One typical key combination is Alt+Tab, used by Windows and KDE (by default, though this is user-configurable); another is apple key-tilde, used by Macintosh. Pressing the appropriate key combination typically cycles through all visible windows in some order, though other actions are possible.

Many, though not all, window managers provide a region of the screen containing some kind of visual control (often a button) for each window on the screen. Each button typically contains the title of the window and may also contain an icon. This area of the screen generally provides some kind of visual indication of which window is active—for example, the active window's button may appear “pushed in”. It is also usually possible to switch the active window by clicking on the appropriate button. In Microsoft Windows, this area of the screen is called the taskbar; in Apple Macintosh systems this area of the screen is called the dock.

The active window may not always lie in front of all other windows on the screen. The active window is simply the window to which keys typed on the keyboard are sent; it may be visually obscured by other windows. This is especially true in window managers which do not require a click to change active windows: FVWM, for example, makes active the window under the mouse cursor but does not change its Z-order (the order in which windows appear, measured from background to foreground). Instead, it is necessary to click on the border of the window to bring it to the foreground. There are also situations in click-to-focus window managers such as Microsoft Windows where the active window may be obscured; however, this is much less common.

title: Window manager


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Talk:Window manager

Merger Proposal
This article should be merger with X window manager as they both serve the same purpose. This article covers the same subject and there is no real need for it. The Windows specific sections of this article could be put into a new section in the X window manager article named something like "Other Platform Window Managers". bobbo (talk) 21:39, 2 January 2008 (UTC)

 * Disagree (Update). I have updated this article to contain more general information about window managers. Although in principle I agree that X window managers is more detailed, many of the articles that link to this article have nothing in particular to do with x windows or linux/UNIX and therefore if it is to be merged into something it should be the Windowing system or another more general article for sure. That is my expert opinion as an information technology professional. Although having an up to date page on window managers is in my opinion very valuable as a way to tie windowing systems, X window managers, compositing window managers (which windows and mac also contain), as well as almost every other platform historical or current which has used windows. It's a nice way to tie it all up in a nice package. I also strongly disagree with the opening comment here. The article, properly written should most certainly not cover the "same subject" and there should be a read need for it. Everyone does not use X window managers. Almost everyone uses a window manager. It's something 90% of people use vs. a fraction of people for X window managers. Putting a section in window manager for X window managers would make sense, since X window managers are window managers. However putting a section in X window managers for window managers would not make sense, since all window managers are not X window managers. Andy16666 (talk) 13:47, 20 April 2008 (UTC)

 * Disagree. Although I agree with all the reasons proposed by the others here, all window managers are not X window managers, and every graphical operating system has at least one. I think you need a general window manager article, unfortunately you also need someone to write one. I think I just found myself a job. :-P Andy16666 (talk) 13:47, 20 April 2008 (UTC)
 * Agree. This article looks very out-of-date, while X window manager looks much more current. MoraSique (talk) 19:26, 12 January 2008 (UTC)
 * Agree with merging the x11 stuff, per nom and MoraSique. Disagree with nom regarding non-x11 stuff, as it's off-topic there. I think Windowing system would be a better place for it (could expand the "other" sentence into a separate subsection about MSWindows platforms). DMacks (talk) 16:44, 16 January 2008 (UTC)
 * Agree. As all but AfterSTEP are window managers for the X11 system, they really should be added to said article, either that or this article should be expanded.  As for AfterSTEP, are there any appropriate places to mention it?  There aren't too many other window managers for Windows, about the only one I can think of (if it even counts) is 98lite.  I agree that having a subsection about window managers on other platforms in the middle of the X11 article seems out of place. Mandanthe1 (talk) 01:46, 22 January 2008 (UTC)
 * Agree. The term "window manager" historically was largely specific to the X11 architecture. IIRC, prior to Vista, MS Windows did not have any component specifically refered to as a window manager in the documentation, and thus the XP discussion is probably OR. 71.134.228.37 (talk) 13:28, 26 November 2008 (UTC)
 * Disagree Window manager doesn't mean X window manager, X window manager is a specific example of a window manager, but is by no means the most common due to the popularity of Windows. This article is also linked to by many articles that are not in reference to the X window manager (such as tiling window manager). – Brandon XLF  (talk) 23:57, 8 December 2019 (UTC)

 * Disagree, per User:BrandonXLF's comment. -- Editor-1 (talk) 07:58, 9 December 2019 (UTC)

Are docks really part of window managers?
The vast majority of X window managers do not include taskbars, docks or desktop icons. Also, in my opinion these parts really have nothing to do with a window manager's main task: managing windows (i.e drawing frames, allowing repositioning of windows etc.). Should these features really be mentioned as being part of window mangers in general?

Pafcu (talk) 08:24, 4 May 2008 (UTC)

 * Agreed. While these features may come with various window manager software, they are not features of a "window manager", just as card games are not a feature of an "operating system" despite their inclusion in Microsoft Windows. Edit. —Centrx→talk • 21:42, 25 May 2008 (UTC)

No Mention of Quartz Compositor?
This article seems to be an overview of window managers, but it fails even to mention Mac OS X's Quartz Compositor. Probably should be in there.

Golem —Preceding unsigned comment added by Ex2golem (talk • contribs) 03:00, 26 July 2008 (UTC)

Too much prominence given to Amiga Workbench
Why is so much prominence and space given to Amiga workbench? This seems inappropriate to spend so much time on a now largely irrelevant window manager from a now effectively extinct OS. More prominence should be given to efforts by Xerox PARC (First GUI/Desktop), Apple (First Commercial GUI success & still relevent) and Windows (Strong in usability and the current desktop market leader).

I guess the Amiga fanboys must of have got the page. Fair enough if you still want to flog this dead horse, but keep that to your amiga forums & fan sites. —Preceding unsigned comment added by 124.168.199.239 (talk) 14:06, 4 May 2010 (UTC)

Need of "See also"
This article really should have a "See also" section with ninternal wikipedia references.

Kjetil Halvorsen 23:20, 19 January 2012 (UTC) — Preceding unsigned comment added by Kjetil1001 (talk • contribs)
 * Information.svg Thank you for your suggestion. When you believe an article needs improvement, please feel free to make those changes. Wikipedia is a wiki, so anyone can edit almost any article by simply following the  link at the top. The Wikipedia community encourages you to be bold in updating pages. Don't worry too much about making honest mistakes—they're likely to be found and corrected quickly. If you're not sure how editing works, check out how to edit a page, or use the sandbox to try out your editing skills.  New contributors are always welcome. You don't even need to log in (although there are many reasons why you might want to). DMacks (talk) 00:16, 20 January 2012 (UTC)

Main image
Shouldn't the main image of the article show KWin as a window manager (that is, listed alongside awesome, Compiz and Openbox), instead as a display server? — Preceding unsigned comment added by Magerasto (talk • contribs) 17:50, 6 April 2020 (UTC)
 * The main image of the article should show a diagram that handles multiple window system architectures.
 * X11 originally had a display server that did all the drawing and clients, including window managers, that asked it to do window drawing, moving, etc.. The Composite extension to X apparently allows window managers to do compositing, as per Compositing window manager.  So:
 * With the Classic X11 Protocol and an old-fashioned window manager, the X11 server is the display server, the old-fashioned window manager is the window manager, and the clients talk to the server directly (usually via a toolkit) and to the window manager via, as I remember, properties attached to the window, e.g. a window title. I guess X11 could run without a window manager, but you aren't going to be able to draw windows around the screen, and you might not get much in the way of borders or get a title bar at all. For that architecture, the main image, as it currently exists, would have X.org Server as a display server, but none of the window manaagers would be counted as the "display server" - they'd all be "window managers".
 * With the X11 Composite extension, it appears that the X11 server can maintain off-screen full images of all windows and composite them onto the screen. That's somewhat like the old-fashioned model, except that clients don't have to be told "somebody {moved this window to the front, dragged another window that was in front of it so that it obscures less of it, ...}, so redraw it" or "...redraw these bits of it that used to be obscured" - they can just pretend that the window is always fully exposed and let the server worry about clipping, etc..  Apparently, the X server can also "conveniently invoke an external "compositing manager" client to apply any desired "special effects"---for example, translucency, blurring or drop shadows---along the way."  That could involve an X11 server, a window manager, and a compositing manager, or it could invovle a "compositing window manager" that serves as both a window manager and compositing manager".  The documentation for the Composite extension seems to indicate that a compositing manager would draw to the "Composite Overlay Window", which is a full-screen window that's above all other windows; it doesn't indicate how the compositing manager finds out that a client has drawn to one of its windows and that it must re-composite the screen.  For that architecture, there would be three items in the same row - display manager, window manager, and compositing manager, with an indication that the last two can be combined into a compositing window manager.  X.org Server would again be an example of a display server; KWin, Mutter, and Compiz would be examples of compositing window managers, xcompmgr would be an example of a compositing manager, and various traditional managers lacking compositing, such as twm, awesome, and Openbox would be example of window managers. And, while an external compositing manager is involved in the process of drawing on the user's screen, it does so through the X11 server, so I'm not sure I'd call them display servers.
 * With Wayland, the display server, compositing manager, and window manager are all in one server, called a Wayland compositor. For that architecture, Weston, KWin and Mutter would be examples of compositors, so, while in an X11 environment KWin and Mutter aren't display servers, in a Wayland environment they are display servers.  I think the Wayland protocol is a lot simpler than the X11 protocol, as 1) it's newer and 2) most of the rendering work is, I think, supposed to be done by the client, with the display server just compositing the resulting rendered windows.
 * In macOS, the Quartz Compositor, also known as WindowServer (that's the name of the executable) is a compositor that acts as a display server and compositor; I'm not sure how many of the window manager functions it handles and how many are handled by the client.
 * In Windows Vista and later, the Desktop Window Manager is a compositor, but I don't know whether it runs as a server in a separate process, and don't know how many of the window manager functions it handles and how many are handled by the client.
 * So that image is a bit of a mess. For example, you have KWin and Mutter marked as display servers, perhaps because that's the function they serve in Wayland, even though in pre-compositing X11 they were window managers and in X11-with-compositing they're compositing window managers but not display servers, and you have Compiz marked as window managers even though it's also a compositing window manager.
 * (And then, just for fun, there's now a choice of client-side decoration with X11 and Wayland, where the application can draw the window decorations rather than having the window manager draw them. How do I know about this? Because Qt, which Wireshark uses as its toolkit, doesn't handle client-side decorations in the version in many Linux distributions, and Mutter only supports client-side decorations, at least on Wayland, so Wireshark - and other Qt applications - have some issues when running on GNOME+Wayland. All I have to say about that is "life's too short for this U+1F4A9".) Guy Harris (talk) 08:20, 13 June 2023 (UTC)

title: Talk:Window manager


text:
Talk:W. A. Draves

POV notice
I copyedited the article and edited it for POV and removed the POV notice. If you want to reinstate the notice, please feel free but write on this page why you're reinstating it. Note that the VfD notice is still valid, but as of now it looks like the article is going to be kept. Salasks 21:18, Aug 3, 2004 (UTC)

title: Talk:W. A. Draves