text:
Wikiversity:Candidates for Custodianship/Countrymike/Interview

''Note: shortly after the original interview was posted on 2nd January, Countrymike left a note on the talk page comparing the interview to McCarthyism. Please see the talk page for this comment. The candidate then answered the questions on 15th January, taking the interview seriously, as below. People are invited to refer to the Wikipedia guide to requests for adminship, which in particular points out that requests for adminship can be met with extremely gruelling procedures in which every edit/comment is called into question, and recommends to candidates that they see this as an opportunity for showing their abilities to deal with conflicts. '' --McCormack 11:30, 16 January 2008 (UTC)

 * My comment regarding the interrogative nature of the dialog with McCormack came after this post by him:

 * "An ambassador is just a nice way to say "spin doctor", "spammer" or "advocate"; all the words have to do with marketing. Wikimedia projects are constantly the target of forms of vandalism which attempt to attract attention to particular websites or viewpoints. Edit-and-run vandals are easy to fix. The tougher vandals are the ones who infiltrate deeply and non-obviously into the system, manipulating content in the long term, never quite enough to become conspicuous. Many link-spam vandals never actually see themselves as vandals - they may genuinely believe in the usefulness of their edits and the validity of their viewpoints, and they may be not fully aware of policies on neutrality and the ban on advocacy. Perhaps Brent has really not realised that his "ambassadorial" platform can be seen as precisely this. There are issues which need to be explored here such as the difference (if any) between what Brent is proposing and (banned) advocacy. We need to think about an ethics code for custodians. It would be an interesting experiment to propose to Brent that custodians adopt an ethics code in which they ban themselves from ever mentioning any external site with which they are associated - would he prefer to continue with his candidacy? or remain an advocate? Which is more important to him? I would encourage Brent not to perceive this as an attack on him, but as an opportunity to reflect on his intentions, to learn from the wiki-way, and to modify his perception of himself and his goals here so that he can play a more valuable role."

 * By this time the constant questioning of my trust in relation to this project and the suggestion that I was some kind of "sleeper vandal" was starting to wear on me, particularly so early on in my mentorship (there is supposed to be a period of 5 days after the probationary month). I was not going to answer these questions from McCormack because it seemed that the debate was being designed as a constant rhetorical rounding up, and painting me in clothes that I don't wear. I have responded now in reqeust from my mentor JWS. It should also be noted that the reference to Wikipedia Admin policy was added here on January 6th by User:McCormack and that no custodian before me (particularly not McCormack) has been subjected to such extremely gruelling procedures, and I would hope that no applicants after me will be asked to "modify their perceptions of themselves", which sounds a little like a suggestion to confess to something that you have been accused of but haven't done. Countrymike 22:05, 16 January 2008 (UTC)
 * These extremely gruelling procedures are what allow the community to verify and assert the integrity of custodians who are entrusted with a level of control over the project. Potential custodians are faced with them where necessary, and while McCormack's wording could have been slightly different there is little reason why you should not answer such questions. While you are granted rights as a custodian, you have a responsibility for transparency towards the community that goes beyond sysop action logs. --Draicone (talk) 12:23, 19 January 2008 (UTC)
 * I think it is an error to look to Wikipedia for insight into how to run a wiki community. The system that exists there for selecting sysops is particularly dysfunctional....it contributes heavily to the caustic and in-civil atmosphere of Wikipedia, an atmosphere that is the subject of embarrassment and concern at the Foundation level. Much of the fundamental structure of Wikiversity has been established to avoid the errors of Wikipedia. There is no excuse to violate the fundamental Wikiversity policy Assume Good Faith. As far as I can tell, McCormack does not like Wayne Mackintosh and WikiEducator and rather than judge Countrymike on his history of participation at Wikiversity, McCormack is creating a big witch hunt based on his fears about how Countrymike, through his association with WikiEducator, might damage Wikiversity in the future. "little reason why you should not answer such questions" <-- I think the questions from McCormack violate the Assume Good Faith policy and are designed to prevent Countrymike from working towards his stated goal of promoting cooperation between Wikiversity and WikiEducator. In contrast to McCormack's xenophobic approach, think we should work towards constructive interactions between education-oriented wikis. In my view, a reasonable way to deal with someone who does not follow the Assume Good Faith policy is to refuse to have anything to do with them, including ignoring their questions. I commend Countrymike for being willing to hold his nose and answer McCormack's questions....questions that as far as I can tell only increase "transparency towards the community" in that they reveal the depth of McCormack's xenophobia and paranoia. --JWSchmidt 17:48, 19 January 2008 (UTC)

Interview with the candidate
This is an interview with User:Countrymike, conducted as part of his request to become a Wikiversity custodian. Questions are designed to be penetrating and challenging, as befits a candidate for a role of trust.

 * 1) McCormack: Thank you for being here. Understanding other people's points of view is important for a custodian, so could you start by telling us why some people might regard your request for custodianship at Wikiversity as controversial?
 * So far the only person that I know of who has viewed my custodianship as "controversial" is the interviewer, McCormack who has subjected me to an interrogation previously unseen in the process of custodianship. James' suspicion of me stems primarily from my relationship with another educational wiki, WikiEducator. Most people who know me on Wikiversity, know my relationship with this wiki. James' seems to have established a vision of me as some kind of "sleeper vandal" just waiting to do long term damage to Wikiversity. I'd like to assure the community here that this is a total fantasy and not at all the case as I think my edit history, the learning projects I have started, my discussions on IRC, my relationships with other Wikiversity participants, and my general contributions towards the Open Educational Resource movement would attest to. Countrymike 21:27, 15 January 2008 (UTC)
 * 1) McCormack: You have stated that your main reason for wanting to be a custodian is to enable you to act as an ambassador for an external site. These diplomatic goals could equally well be fulfilled without access to the admin "privileges" of deleting, blocking and protecting pages, and you have expressed an interest in nevertheless having access to these admin "privileges" as well. Please feel welcome to extend your original request for custodianship by adding additional reasons why you feel you need access to these admin "privileges".
 * As I have argued elsewhere, Custodianship is not only about access to the tools; a custodian should be considered also as a person entrusted with the custody or care of something, this entails welcoming new users, adding categories, or representing Wikiversity in a positive way to participants, administrators, and founders of other open educational projects. In my work in the OER community I often have opportunity to suggest that people take a look at Wikiversity and often specific projects within the site; carrying the label of custodian of the project helps me establish a level of confidence and trust between potential new participants and myself. Access to the tools helps me in the administrative duties that also come with being a custodian, but I think its wrong to conflate custodianship as only designating access to these tools. Countrymike 21:27, 15 January 2008 (UTC)
 * 1) McCormack: You have stated that there are two websites, including Wikiversity, which you are mostly involved with, but your edit counts suggest a preference for the other one. Is your loyalty primarily for one or the other? Where would your loyalty lie in case of conflict?
 * I was involved in WikiEducator from its inception and have done a lot of work over there to get it to where it is today; that site also has a lot less experienced editors than here who often require more help than editors on Wikiversity do; this may account for my edit count. I wouldn't like to think that there would ever be a 'conflict' and I would do my best to see that this was not the case; as I have often stated that I think the two projects have differing yet complementary missions. Countrymike 21:27, 15 January 2008 (UTC)
 * 1) McCormack: was Erik Möller correct to call Wikiversity a "mess" and to praise WikiEducator by comparison? Even if he was correct, was it a breach of trust for him to use his role as Deputy Director of the Wikimedia Board to state such things in public?
 * I don't believe that Erik knows enough about Wikiversity to have had the status to call it much of anything, but it also doesn't take much experience on Wikiversity to see that yes - Wikiversity is a bit of a mess ... but most wikis in their early stages are just that and I don't think that WikiEducator is any less of a mess either. I'd rather not comment on Erik's new role as Deputy Director. Countrymike 21:27, 15 January 2008 (UTC)
 * 1) McCormack: In the current climate of tension over the Möller statements, how have you exercised your diplomatic skills as an ambassador? You are, of course, closely associated with Erik as joint leader of the other site. Have you remonstrated with Erik that his statements are insensitive, incorrect and inappropriate? Would you go on record with strong criticism of him? Or do you think your diplomatic skills would be better directed towards helping the Wikiversity community accept that he is right?
 * There isn't really a "climate of tension"; lets just get on with it. I'm not that closely associated with Erik, we have little to do with each other really. This question is a bit loaded don't you think? I'm not really into strongly criticising anyone, especially someone who from my limited dealings with him has shown a strong dedication to the freedom culture movement; the Wikiversity community will have a range of diverse opinions about Erik and the WMF board, thats fine. Countrymike 21:27, 15 January 2008 (UTC)
 * 1) McCormack: Advocacy is a breach of neutrality, which is an absolute value of all Wikimedia projects. Do you think custodians should be more highly bound to this ethical code, or exempted from it? How does your proposed "ambassadorship" differ from advocacy, and how would you avoid any possibility of your site gaining exposure or visitors from your ambassadorship?
 * I don't agree that 'advocacy' is a breach of neutrality. Countrymike 21:27, 15 January 2008 (UTC)
 * 1) McCormack: As an especially fervent supporter of the Free Software Foundation, you have strong views about the meaning of the word "freedom". Do you think those views should influence the content or merely the licencing of edits at Wikiversity? Can you explain, in this context, why you find Benjamin Cardozo's statements on freedom controversial and inappropriate for inclusion on Wikiversity?
 * "fervent supporter of the Free Software Foundation"? don't know where this comes from. I just think that being overly obsessed with "freedom" is a dangerous thing. History is littered with the trampled bodies of those who got in the way of others championing their idea of freedom. Countrymike 21:27, 15 January 2008 (UTC)
 * 1) McCormack: As a custodian, should it be your duty to help Wikiversitarians and visitors understand and adhere more strongly to the views of the Free Software Foundation?
 * No. It should be to help them use this tool/platform to learn and teach. Countrymike 21:27, 15 January 2008 (UTC)
 * 1) McCormack: Perhaps the Wikiversity/Wikieducator relationship could be likened to that of a boy/girlfriend break-up where one side just won't stop phoning and saying "we have to talk about this"? Wouldn't it solve Wikiversity's problems if Wikieducator just stayed away and stopped trying to market itself at Wikimedia or play the uninvited guest?
 * Wikiversity's problems can only be solved by Wikiversity; its not a competition. Countrymike 21:27, 15 January 2008 (UTC)
 * 1) Draicone: What are your thoughts on the role of custodianship for yourself, given that you also intend to act as an ambassador for the WikiEducator project? Please describe what actions you have in mind to be taken a) as a custodian and b) as a representative of WE, and any relationship between these.
 * 2) Draicone: What do you personally feel about this debate regarding your inevitable NPOV issues between WE and WV as a custodian? Would you consider using two separate accounts on WV, one for your custodian actions, and another for your input to the community, to be able to demonstrate a clear separation between the two?


text:
User talk:Pompuspb

Welcome
Hello Pompuspb, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. To get started, you may
 * Take a guided tour and learn to edit;
 * Explore our learning projects;
 * Browse our portals, schools, and research activities;
 * Read and help develop our community policies；or
 * Chat with other Wikiversitans on #wikiversity-en.

And don't forget to explore Wikiversity with the links to your left. Be bold, and see you around Wikiversity! --JWSchmidt 17:13, 2 January 2008 (UTC)

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

title: User talk:Pompuspb


text:
User:Juandev/MMech

MMech is an abbreviation for a subject I had this semester. It was about agriculture and farm machinery and mechanization in general. It was teached in English and Czech, but I expect the exam will be in English, thats why I am here on en. '''Anyway I should mentioned in here, that subject in two languages is a very bad idea and all us that have to suffer this stupid system have difficulties to hadle a knoweledge. Lets choose a language dear teachers, but one langauge is enought!'''

Methodology
Well in this case, when there is enough time before exam I can use a method "step-by-step":
 * I have some written lectures, which I really like - for hard studying (something like imprinting - ha, ha), but not all
 * I need to put these lectures in date order
 * I need to translate unknown words from English ones
 * than I need to complete to have all lectures in handwritten form - there is a problem, that the textbook for this subject doesnt exist nor sillaby - so I should ask my friends
 * It will be necessary to understandt it - there is counting and there are things to understant
 * urgent need to know sillaby or how the exam will look like!
 * urgent need to know sillaby or how the exam will look like!

Observations
During the last 5 years on University, I have realized:
 * its better to attend all lectures, even they are incredibly boring - this I mean in the sence, I remember something
 * its better to write down notes on incredibly boring lectures - then there is a less work before exam (this doesnt work, if the teacher is explaining something hole semester and than tests from something different - this happened me twice and I think, these teachers should be recycled)
 * I prefer full text textbooks than slideshows to study for exam - even it is with more pages

title: User:Juandev/MMech


text:
Wikiversity talk:Candidates for Custodianship/Countrymike/Interview

Wow! This is sounding scaringly like another McC *. Countrymike 18:38, 2 January 2008 (UTC)


text:
German grammar/Past participle

Sein – war – gewesen

title: German grammar/Past participle


text:
Template:Sisterprojects/Ar

 ويكي الجامعة مستضاف من قبل مؤسسة ويكيميديا, منظمة لا ربحية تستضيف ايضا   انواع اخرى من مشاريع متعددة اللغات و محتوى-مجاني :

title: Template:Sisterprojects/Ar


text:
Complex semi-simple Lie algebras and their representations

under construction

In this course we learn the basics of complex semi-simple Lie algebras.

Why?

 * the classification of compact Lie groups reduces to the classification of semi-simple Lie algebras
 * the key notion of a root system reappears in many branches of mathematics and theoretical physics
 * Lie algebras and their representations are intimately related to quantum mechanics

on paper
In increasing order of details:
 * J.-P. Serre, Complex semi-simple Lie algebras (translated from French: Algebres de Lie complex semi-simple
 * J. E. Humphreys, Introduction to Lie algebras and representation theory, ISBN 978-0-387-90053-7
 * W. Fulton, J. Harris, Representation theory, A first course

on line
There is plenty of lecture notes and other good references on line to suit every taste.
 * semisimple+Lie+algebras

lessons

 * Lie algebra
 * Linear Lie algebras
 * /derivations and automorphisms
 * soluable and nilpotent Lie algebras
 * representations of Lie algebras
 * examples: classical Lie algebras
 * example: representations of sl2
 * Lie's theorem and Engel's theorem
 * Schur's lemma
 * Casimir element
 * Weyl's theorem on complex reducibility
 * Killing form
 * Cartan subalgebra
 * Borel subalgebra
 * roots and weights of a Lie algebra
 * root system
 * Cartan matrix
 * Dynkin diagram
 * Verma module
 * Harish-Chandra's theorem
 * Weyl character formula
 * Kostant's multiplicity formula
 * Poincare-Birkhoff-Witt theorem

beyond

 * Lie group
 * algebraic group
 * Kac-Moody algebra
 * quantum algebra
 * vertex algebra


text: Category:Lie algebra

title: Category:Lie algebra


text: User:Whiteknight/Count Ticker/2008/January


text:
User talk:David-i98~enwikiversity

Welcome
Hello David-i98, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. To get started, you may
 * Take a guided tour and learn to edit;
 * Explore our learning projects;
 * Browse our portals, schools, and research activities;
 * Read and help develop our community policies；or
 * Chat with other Wikiversitans on #wikiversity-en.

And don't forget to explore Wikiversity with the links to your left. Be bold, and see you around Wikiversity! --Countrymike 02:23, 3 January 2008 (UTC)

Your account will be renamed
Hello,

The developer team at Wikimedia is making some changes to how accounts work, as part of our on-going efforts to provide new and better tools for our users like cross-wiki notifications. These changes will mean you have the same account name everywhere. This will let us give you new features that will help you edit and discuss better, and allow more flexible user permissions for tools. One of the side-effects of this is that user accounts will now have to be unique across all 900 Wikimedia wikis. See the announcement for more information.

Unfortunately, your account clashes with another account also called David-i98. To make sure that both of you can use all Wikimedia projects in future, we have reserved the name David-i98~enwikiversity that only you will have. If you like it, you don't have to do anything. If you do not like it, you can pick out a different name.

Your account will still work as before, and you will be credited for all your edits made so far, but you will have to use the new account name when you log in.

Sorry for the inconvenience.

Yours, Keegan Peterzell Community Liaison, Wikimedia Foundation 23:33, 17 March 2015 (UTC)

Renamed
 This account has been renamed as part of single-user login finalisation. If you own this account you can |log in using your previous username and password for more information. If you do not like this account's new name, you can choose your own using this form after logging in: . -- Keegan (WMF) (talk) 06:05, 19 April 2015 (UTC)

title: User talk:David-i98~enwikiversity


text:
User talk:Amyleverett

Welcome
Hello Amyleverett, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. To get started, you may
 * Take a guided tour and learn to edit;
 * Explore our learning projects;
 * Browse our portals, schools, and research activities;
 * Read and help develop our community policies；or
 * Chat with other Wikiversitans on #wikiversity-en.

And don't forget to explore Wikiversity with the links to your left. Be bold, and see you around Wikiversity! --Countrymike 02:24, 3 January 2008 (UTC)

title: User talk:Amyleverett


text:
User talk:Pilgrim~enwikiversity

Welcome
Hello Pilgrim, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. To get started, you may
 * Take a guided tour and learn to edit;
 * Explore our learning projects;
 * Browse our portals, schools, and research activities;
 * Read and help develop our community policies；or
 * Chat with other Wikiversitans on #wikiversity-en.

And don't forget to explore Wikiversity with the links to your left. Be bold, and see you around Wikiversity! --Countrymike 02:24, 3 January 2008 (UTC)

Your account will be renamed
Hello,

The developer team at Wikimedia is making some changes to how accounts work, as part of our on-going efforts to provide new and better tools for our users like cross-wiki notifications. These changes will mean you have the same account name everywhere. This will let us give you new features that will help you edit and discuss better, and allow more flexible user permissions for tools. One of the side-effects of this is that user accounts will now have to be unique across all 900 Wikimedia wikis. See the announcement for more information.

Unfortunately, your account clashes with another account also called Pilgrim. To make sure that both of you can use all Wikimedia projects in future, we have reserved the name Pilgrim~enwikiversity that only you will have. If you like it, you don't have to do anything. If you do not like it, you can pick out a different name.

Your account will still work as before, and you will be credited for all your edits made so far, but you will have to use the new account name when you log in.

Sorry for the inconvenience.

Yours, Keegan Peterzell Community Liaison, Wikimedia Foundation 23:41, 17 March 2015 (UTC)

Renamed
 This account has been renamed as part of single-user login finalisation. If you own this account you can |log in using your previous username and password for more information. If you do not like this account's new name, you can choose your own using this form after logging in: . -- Keegan (WMF) (talk) 06:17, 19 April 2015 (UTC)

title: User talk:Pilgrim~enwikiversity


text:
User talk:Sabir58

Welcome
Hello Sabir58, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. To get started, you may
 * Take a guided tour and learn to edit;
 * Explore our learning projects;
 * Browse our portals, schools, and research activities;
 * Read and help develop our community policies；or
 * Chat with other Wikiversitans on #wikiversity-en.

And don't forget to explore Wikiversity with the links to your left. Be bold, and see you around Wikiversity! --Countrymike 02:25, 3 January 2008 (UTC)

title: User talk:Sabir58


text:
Virus

A virus is a small, non-living infectious obligate intracellular parasite that replicates itself inside the living cells of other organisms. Viruses must reproduce by infecting living cells and using the living cells machinery to produce new viruses. These infectious agents can either contain DNA or RNA as their genetic material, and also contain a protein coat, known as capsid. They are also very specific in the cells that they infect, each virus infecting specific cells either infect them through a lytic cycle or lysogenic cycle. According to Kurtzgesagt, a virus is a hull around genetic material.

Bacteriophages
A bacteriophage is a virus that infects bacteria and usually has a helical structure or an icosahedral structure.

Plant Viruses
A plant virus is a virus that infects plants. They usually have a rod/polyhedral shape. The best-known plant virus is the rod-shaped tobacco-mosaic virus.

Animal (Eukaryotic) Viruses
A animal virus, example being: Ebola, is a virus that infects animals. Usually, these viruses have a helical/icosahedral structure and can be "naked" or "envelope". Naked viruses have a protein capsid but no lipid envelope, which "envelope" can mean a lipid envelope that the virus develops when it leaves the host cell.

Retrovirus
A retrovirus is a virus that contains RNA instead of DNA as their genetic material. RNA must be converted back to DNA--once changed, DNA is then inserted into DNA of the host cell. This requires an enzyme known as reverse-transcriptase so that RNA can be copied back to RNA. A good example of a retrovirus is HIV.

Germ Theory of Infectious Diseases
The Germ theory of disease is an accepted scientific theory relating to germs proposed by Italian scientist Girolamo Fracastoro. The theory states that microorganisms are the cause of many diseases.
 * Five Ways to Contract a Disease
 * 1) Viruses
 * 2) Bacteria
 * 3) Protists
 * 4) Fungi
 * 5) Worms
 * 6) Coughing or sneezing near an uninfected person if the person who ejects their mucus is infected.

title: Virus


text:
User:Marshallsumter/Original research/Physics

Physics is a study of how the universe appears to work. It has been defined as a "science that deals with matter and energy and their interactions" and as the branch of science concerned with the study of properties and interactions of space, time, matter and energy.

This resource is part of a series of resources from the department of physics.

Times
A key value on the time axis for collecting physical data is the starting time. “Incandescents reach full brightness a fraction of a second after being switched on.”

An atomic clock is a clock device that uses an electronic transition frequency in the microwave, optical, or ultraviolet region of the electromagnetic spectrum of atoms as a frequency standard for its timekeeping element. Atomic clocks are the most accurate time and frequency standards known, and are used as primary standards for international time distribution services, to control the wave frequency of television broadcasts, and in global navigation satellite systems such as GPS.

The FOCS 1 continuous cold cesium fountain atomic clock started operating in 2004 at an uncertainty of one second in 30 million years. The clock is in Switzerland.

Conditions
Eventually it occurred to many of the intelligent life forms on Earth that in addition to where the observations of the natural objects or entities in the sky are taken, also when and how the observations are taken is important. The results of observations change with time, temperature, and other atmospheric conditions.

Many of the early laws begin to make sense and increase understanding of the phenomena observed when coupled to experimental and theoretical studies performed in a laboratory here on Earth under controlled conditions. Astronomy benefits from physics.

Laboratory conditions are often expressed in terms of standard temperature and pressure.

Standard condition for temperature and pressure are standard sets of conditions for experimental measurements established to allow comparisons to be made between different sets of data. The most used standards are those of the International Union of Pure and Applied Chemistry (IUPAC) and the National Institute of Standards and Technology (NIST), although these are not universally accepted standards. Other organizations have established a variety of alternative definitions for their standard reference conditions.

In chemistry, IUPAC established standard temperature and pressure (informally abbreviated as STP) as a temperature of 273.15 K (0 °C, 32 °F) and an absolute pressure of 100 kPa (14.504 psi, 0.986 atm, 1 bar), An unofficial, but commonly used standard is standard ambient temperature and pressure (SATP) as a temperature of 298.15 K (25 °C, 77 °F) and an absolute pressure of 100 kPa (14.504 psi, 0.986 atm). The STP and the SATP should not be confused with the standard state commonly used in thermodynamic evaluations of the Gibbs free energy of a reaction.

"Standard conditions for gases: Temperature, 273.15 K [...] and pressure of 105 pascals. The previous standard absolute pressure of 1 atm (equivalent to 1.01325 × 105 Pa) was changed to 100 kPa in 1982. IUPAC recommends that the former pressure should be discontinued."

NIST uses a temperature of 20 °C (293.15 K, 68 °F) and an absolute pressure of 101.325 kPa (14.696 psi, 1 atm). The International Standard Metric Conditions for natural gas and similar fluids are 288.15 K (59.00 °F, 15.00 °C) and 101.325 kPa.

Line of sight
Def. a straight line along which an observer has a clear view is called line of sight.

In the section on 'senses' is a demonstration of the principle of 'line of sight'; i.e., "a line from an observer's eye to a distant point toward which [the observer] is looking". In the image on the left of rain beneath a dark cloud, there is a highway with a vehicle on it. The vehicle is further away from the observer than the right turn onto a side road. Is the blue sky behind the dark cloud? Is the line of trees in the background further away than the dark cloud? Many objects in this image and the others can be layered relative to the observer (some are closer by inspection than others). These layers or strata are strata along the line of sight. The principle of line of sight can be used to make deductions about the relative locations (or positions) of objects from the observer's perspective.

By observing many of the wandering lights in the night sky, an occasional occultation of the light of one astronomical object may occur by the intervention of another along a closer astronomical stratum. On April 25, 1838, an occultation of Mercury by the Moon occurred when Mercury was visible to the unaided eye after sunset. An occultation of Venus by the Moon occurred "on the afternoon of October 14", 1874. An earlier such occultation "occurred on May 23, 1587, and is thus recorded by [Tycho Brahe] in his Historia Celestis". "Thomas Street, in his Astronomia Carolina (A.D. 1661), mentions three occultations by Venus, being two occasions when the planet covered Regulus, and once when there was an occultation of Mars by Venus." "[Thomas Street] describes [the occultation of Mars by Venus] as follows: "1590,. Oct. 2nd, 16h. 24s. Michael Mœstlin observed ♂ eclipsed by ♀.""

Coordinates
A Cartesian coordinate system specifies each point uniquely in a plane by a pair of numerical coordinates, which are the signed distances from the point to two fixed perpendicular directed lines, measured in the same unit of length. Each reference line is called a coordinate axis or just axis of the system, and the point where they meet is its origin, usually at ordered pair (0,0). The coordinates can also be defined as the positions of the perpendicular projections of the point onto the two axes, expressed as signed distances from the origin.

Distances
Def. an amount of space between two points, usually geographical points, usually (but not necessarily) measured along a straight line is called a distance.

Distance (or farness) is a numerical description of how far apart objects are. In physics or everyday discussion, distance may refer to a physical length, or an estimation based on other criteria (e.g. "two counties over"). In mathematics, a distance function or metric is a generalization of the concept of physical distance. A metric is a function that behaves according to a specific set of rules, and provides a concrete way of describing what it means for elements of some space to be "close to" or "far away from" each other.

Empty spaces
In set theory, emptiness is symbolized by the empty set: a set that contains no elements.

Def. the state of being devoid of content; containing nothing is called empty.

Free space, a perfect vacuum is expressed in the classical physics model. Vacuum state is a perfect vacuum based on the quantum mechanical model. In mathematical physics, the homogeneous equation may correspond to a physical theory formulated in empty space are disambiguations for "empty space".

In astronomy, voids are the empty spaces between filaments (the largest-scale structures in the Universe), which contain very few, or no, galaxies. ... Voids located in high-density environments are smaller than voids situated in low-density spaces of the universe.

Forces
Def. a physical quantity that denotes ability to push, pull, twist or accelerate a body which is measured in a unit dimensioned in mass × distance/time² (ML/T²): SI: newton (N); CGS: dyne (dyn) is called force.

Def. a force associated with nuclear decay is called a weak nuclear force.

Def. a residual force associated with the strong bonds responsible for the interactions between nucleons is called the strong nuclear force.

The key values to determine in both force and energy are $$\frac{L}{T^2}$$ and $$\frac{L^2}{T^2}$$. Force (F) x distance (L) = energy (E), $$\frac{L}{T^2} \times L = \frac{L^2}{T^2}$$. Force and energy are related to distance and time using proportionality constants.

Energies
Def. a quantity that denotes the ability to do work and is measured in a unit dimensioned in mass × distance²/time² (ML²/T²) or the equivalent is called energy.

The energy $$E$$ for the system in the section about forces is

 * $$E = F \cdot D,$$

where $$D$$ is the displacement.

Fields
Def. a region affected by a particular force is called a field.

Def. a region of space around a charged particle, or between two voltages; it exerts a force on charged objects in its vicinity is called an electric field.

Def. a condition in the space around a magnet or electric current in which there is a detectable magnetic force and two magnetic poles are present is called a magnetic field.

Gravity
Def. the fundamental force of attraction that exists between all particles with mass in the universe is called gravitation.

Masses
Def. the basic structural component of the universe [that] usually has mass and volume is called matter.

In physics, mass, more specifically inertial mass, can be defined as a quantitative measure of an object's resistance to the change of its speed. In addition to this, gravitational mass can be described as a measure of magnitude of the gravitational force which is when interacting with a second object. The SI unit of mass is the kilogram (kg).
 * 1) exerted by an object (active gravitational mass), or
 * 2) experienced by an object (passive gravitational force)

Measurements
Measurement is the process or the result of determining the ratio of a physical quantity, such as a length, time, temperature etc., to a unit of measurement, such as the meter, second or degree Celsius.

Physical units
Def. "exactly 149,597,870.691 kilometres" is called one AU.

Def. "86,400 SI seconds (s)" is called 1 day (d).

Def. "1.9891 x 1030 kg" is called the mass of the Sun.

Def. "9,460,730,472,580.8 km" is called the light-year (ly).

Fissions
In nuclear physics and nuclear chemistry, nuclear fission is either a nuclear reaction or a radioactive decay process in which the nucleus of an atom splits into smaller parts (lighter nuclei). The fission process often produces free neutrons and photons (in the form of gamma rays), and releases a very large amount of energy, even by the energetic standards of radioactive decay. [...] The two nuclei produced are most often of comparable but slightly different sizes, typically with a mass ratio of products of about 3 to 2, for common fissile isotopes. Most fissions are binary fissions (producing two charged fragments), but occasionally (2 to 4 times per 1000 events), three positively charged fragments are produced in a ternary fission. The smallest of these fragments in ternary processes ranges in size from a proton to an argon nucleus.

Fusions
Nuclear fusion is a nuclear reaction in which two or more atomic nuclei come very close and then collide at a very high speed and join to form a new type of atomic nucleus. During this process, matter is not conserved because some of the matter of the fusing nuclei is converted to photons (energy). Fusion is the process that powers active or "main sequence" stars.

The fusion of two nuclei with lower masses than iron (which, along with nickel, has the largest binding energy per nucleon) generally releases energy, while the fusion of nuclei heavier than iron absorbs energy. The opposite is true for the reverse process, nuclear fission. This means that fusion generally occurs for lighter elements only, and likewise, that fission normally occurs only for heavier elements. There are extreme astrophysical events that can lead to short periods of fusion with heavier nuclei. This is the process that gives rise to nucleosynthesis, the creation of the heavy elements during events such as supernovae.

Radiation
Def. an action or process of throwing or sending out a traveling ray in a line, beam, or stream of small cross section is called radiation, from radiation astronomy.

The term radiation is often used to refer to the ray itself.

Radiation comes in many forms and energies.

Notation: let various International System of Units, SI prefixes, occur before the unit of energy, the electronvolt, abbreviated as eV.

For example, PeV denotes 1015 eV.

Cosmic rays may be upwards of a ZeV (1021 eV). Ultra high energy neutrons are around an EeV (1018 eV). But, X-rays only range up to about 120 keV, while the visible (visual) range is around 2 eV.

Astronomy likely started with visual astronomy. Visual refers to that portion of the electromagnetic spectrum called the visible spectrum. Probing the sky with additional portions of this spectrum is difficult as the atmosphere absorbs over many portions.

This has produced fields of observational astronomy based on some portions of the electromagnetic spectrum:
 * 1) Gamma-ray astronomy,
 * 2) X-ray astronomy,
 * 3) Ultraviolet astronomy,
 * 4) Infrared astronomy, and
 * 5) Radio astronomy.

Recent history
The recent history period dates from around 1,000 b2k to present.

A major thrust of physics over the last few hundred years (since the time of Galileo and Newton) has been to understand the workings of the universe in terms of ever-more-fundamental principles. This has generally involved an understanding of what a "force" means, though modern formulations of forces are very different from what they were in Newton's time.

By the middle of the 20th century, physicists recognized 4 fundamental forces: One unification had already taken place in the 19th century: the previously disparate electric and magnetic forces were combined into the electromagnetic force, due to the work of Oersted, Faraday, and Maxwell.
 * gravity
 * electromagnetism
 * the "strong" nuclear force, responsible for holding nuclei together, and for nuclear power and some types of radioactivity.
 * the "weak" nuclear force, responsible for some other types of radioactivity.

During the 20th century, all of the forces except gravity were reformulated in terms of "gauge theories" within the framework of Quantum Mechanics. The forces act through the exchange of "gauge bosons".

In the 1970's, the electromagnetic and weak forces were unified into the "electroweak force", due to the work of Weinberg, Salam, and Glashow.

In the late 20th century, a "grand unified theory" (GUT) was developed, that attempts to unify the electroweak and strong forces. This is often called the "standard model". It is still under development.

The "theory of everything" (TOE), that would unify the standard model with gravity, is still elusive. Efforts in this area include "string theory" and "supersymmetry".

Hypotheses

 * 1) Although basic physics theory has been composed on the basis of ideal constructs, many and perhaps all of these do not exist in the real universe.


text:
Fluid statics

The study of Fluid Statics (often called Hydrostatics) is the fundamental examination of the effects of forces upon and behavior of stationary fluids (gases and liquids). Often considered the introductory discipline within the field of Fluid Mechanics, Fluid Statics explores the behavior of stationary fluids through the application of mathematics and physics. Fluid Dynamics is the subsequent study of moving fluids.

Mathematics

 * Algebra
 * Trigonometry
 * Calculus
 * Differential Equations

Physics

 * Introduction to physics
 * Classical Mechanics

Texts

 * Fluid_Mechanics

Fluid Statics Lessons

 * Fluid Statics Lesson One

Preliminary Study guide

 * 1) Wikipedia article:Fluid Statics
 * 2) Wikipedia article:Units
 * 3) Wikipedia article:Free Body Diagram
 * 4) Wikipedia article:Potential Energy
 * 5) Wikipedia article:Body Force
 * 6) Wikipedia article:Gravity
 * 7) Wikipedia article:Density
 * 8) Wikipedia article:Static Pressure
 * 9) Wikipedia article:Newtons Laws of Motion
 * 10) Wikipedia article:Bouyancy

Readings

 * Peruse the appropriate sections of Fluid_Mechanics

Activities

 * University of the Virgin Islands: Hydrostatics Page

title: Fluid statics


text:
Fluid dynamics

Fluid dynamics is the sub-discipline of fluid mechanics dealing with fluids (liquids and gases) in motion. It has several subdisciplines itself, including aerodynamics (the study of gases in motion) and hydrodynamics (the study of liquids in motion). Fluid dynamics has a wide range of applications, including calculating forces and moments on aircraft, determining the mass flow rate of petroleum through pipelines, predicting weather patterns, and reportedly modeling fission weapon detonation. Some of its principles are even used in traffic engineering, where traffic is treated as a continuous fluid. Fluid dynamics offers a mathematical structure that underlies these practical disciplines and that embraces empirical and semi-empirical laws, derived from flow measurement, used to solve practical problems. The solution to a fluid dynamics problem typically involves the calculation of various properties of the fluid, such as velocity, pressure, density, and temperature, as functions of space and time.

Introduction
Physical objects are made out of atoms, and in most circumstances are in one of three states; solid, liquid, or gas. Liquids and gases are considered fluids as they are able to be sheared and have no defined volume. This contrasts with solids which are rigid and can only shear for deformation. Fluid atoms or molecules are able to freely or semi-freely float in some mediums allowing them to disperse.

Pressure

 * Pressure is defined as the Force per unit Area, this article will use SI units with units of Force in Newtons (kg*m/s^2) and Area (m^2) as pressure is in N/m^2 equal to 1 Pascal. Pressure can be viewed on how much fluids are pressed to move in a direction, when pressure is applied to a fluid it experiences displacement and in this artcle pressure will be defined with a "p".

 * Density is defined as the Mass per unit Volume, or in SI kg/m^3. Unlike all other units in this article is dependent on tempature. All materials have density and generally for most materials as tempature increases density decreases. Density is dependent on the material used and each material at some tempature will have a defined density. In this article density is defined with a "D".

 * Velocity is defined as Distance per Time, or in SI m/s. It is considered the speed of the fluid and how fast it is moving through space and defined as "v".

Archimedes' principle
Buoyancy is the force of an object submerged in a fluid, Objects submerged displace the same volume of fluid as the fraction of the object submerged, for example a iron cube with a volume 1m^3 dropped into a container of water, the container of water will rise by a volume equal to 1m^3.
 * Objects with a lower density than the density of the fluid they are submerged will float.
 * Objects with a higher density than the density of the fluid they are submerged will sink.

However objects can remain partly submerged, this can be mathamatically described as

Fraction submerged = Volume of object submerged/ Total volume of object = Volume of fluid displaced/Total volume of object.

This could be rearranged by mass/density=volume, we can replace this into the equation like

Fraction submerged = (Mass of object submerged/density of object)/(Mass of fluid/ density of object)

= (Mass of fluid displaced/density of fluid)/(Mass of fluid/ density of fluid).

title: Fluid dynamics


text:
Kinematics of particles

Part of the Dynamics course offered by the Division of Applied Mechanics, School of Engineering and the Engineering and Technology Portal

Equations of Motion
Rectilinear Motion The motion of any particle is most easily described by using the the equations of Rectilinear Motion. Where $$\boldsymbol{s}$$ represents distance or displacement, $$\vec\boldsymbol{v}$$ represents velocity and $$\vec\boldsymbol{a}$$ represents acceleration, it may be remembered from Physics that: $$\vec v = \frac{d s}{dt} = s'$$  and   $$\vec a = \frac{d\vec v}{dt} = \vec v' = s''$$

Curvilinear Motion The motion of any particle along a curved path is most easily described by using the the equations of Curvilinear Motion. Where $$\boldsymbol{\vec r}$$ represents the position of a particle in cartesian or polar coordinates and $$\boldsymbol{\Delta \vec r}$$ is the displacement of said particle, the scalar quantity $$\boldsymbol{s = | \vec r |}$$ represents the distance of the displacement and $$\boldsymbol{\vec v}$$ is the instantaneous velocity of the particle: $$\vec v = \frac{d \vec r}{dt} = r'$$

3D Motion
Motion in three dimensions may be described by the following equations: Rectangular Coordinates (Cartesian) - (x,y,z) $$ \vec R = x \hat i + y \hat j + z \hat k$$ $$ \vec v = \vec R' = x' \hat i + y' \hat j + z' \hat k$$ $$ \vec a = \vec v ' = \vec R = x \hat i + y \hat j + z \hat k$$

Cylindrical Coordinates - (r, $$\theta$$, z) Also see Polar Coordinates (r,  $$\theta$$) $$ \vec R = r \hat e_r + \hat e_\theta + z \hat k$$ $$ \vec v = \vec R' = r' \hat e_r + r \theta ' \hat e_\theta + z' \hat k$$ $$ \vec a = \vec v ' = \vec R = (r-r \theta '^2)\hat e_r + (r\theta+ 2r'\theta')\hat e_\theta + z\hat k$$

Spherical Coordinates - (R, $$\theta$$, $$\phi$$) $$ \vec R = R \hat e_R + \hat e_\theta + \hat e_\phi$$ $$ \vec v = R' \hat e_R + (R\theta' \cos \phi)\hat e_\theta + R\phi\hat e_\phi'$$ $$ \vec a = (R''-R\phi'^2 - R\theta'^2 \cos^2 \phi) \hat e_R + \left( \frac{\cos \phi}{R}\frac{d}{dt}(R^2 \theta') - 2R\theta'\phi'\sin \phi \right) \hat e_\theta + \left( \frac{1}{R}\frac{d}{dt}(R^2 \phi') + R\theta'^2\sin\phi\cos\phi \right) \hat e_\phi$$

Mass Moment of Inertia
Mass Moment of Inertia is the resistance of an object to attempts to accelerate its rotation about an axis. $$I_x = \int (y^2 + z^2)dm$$, $$I_y = \int (x^2 + z^2)dm$$,  $$I_z = \int (x^2 + y^2)dm$$         (4) If the axis of rotation passes through the center of gravity of the rotating object, the calculated $$\ I_c$$ is called the Centroidal Mass Moment of Inertia. (See also the List of moments of inertia on Wikipedia)

Additive Motion & Relative Motion
For a system of two vectors oriented in different directions, the relationsip between the two may be establshed through vector addition. For vectors $$\vec\boldsymbol{v_A}$$ and $$\vec\boldsymbol{v_B}$$, the relative motion of $$\vec\boldsymbol{v_A}$$ from the frame of reference of $$\vec\boldsymbol{v_B}$$ is: $$\vec\boldsymbol{v_A} = \vec\boldsymbol{v_B} + \vec\boldsymbol{v_{A/B}} $$ The calculation of relative motion is completed similarly for acceleration.

Assignments
Activities:
 * Create an activity

Readings:
 * Peruse the appropriate sections of Mechanics

Study guide:
 * 1) Wikipedia article:Cartesian coordinates
 * 2) Wikipedia article:Polar coordinates
 * 3) Wikipedia article:Cylindrical coordinates
 * 4) Wikipedia article:Spherical coordinates
 * 5) Wikipedia article:Displacement
 * 6) Wikipedia article:Distance
 * 7) Wikipedia article:Velocity
 * 8) Wikipedia article:Speed
 * 9) Wikipedia article:Acceleration

title: Kinematics of particles


text:
User talk:Mayankacescholar~enwikiversity

Welcome
Hello Mayankacescholar, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. To get started, you may
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And don't forget to explore Wikiversity with the links to your left. Be bold, and see you around Wikiversity! --Countrymike 07:13, 3 January 2008 (UTC)

Your account will be renamed
Hello,

The developer team at Wikimedia is making some changes to how accounts work, as part of our on-going efforts to provide new and better tools for our users like cross-wiki notifications. These changes will mean you have the same account name everywhere. This will let us give you new features that will help you edit and discuss better, and allow more flexible user permissions for tools. One of the side-effects of this is that user accounts will now have to be unique across all 900 Wikimedia wikis. See the announcement for more information.

Unfortunately, your account clashes with another account also called Mayankacescholar. To make sure that both of you can use all Wikimedia projects in future, we have reserved the name Mayankacescholar~enwikiversity that only you will have. If you like it, you don't have to do anything. If you do not like it, you can pick out a different name.

Your account will still work as before, and you will be credited for all your edits made so far, but you will have to use the new account name when you log in.

Sorry for the inconvenience.

Yours, Keegan Peterzell Community Liaison, Wikimedia Foundation 23:43, 17 March 2015 (UTC)

Renamed
 This account has been renamed as part of single-user login finalisation. If you own this account you can |log in using your previous username and password for more information. If you do not like this account's new name, you can choose your own using this form after logging in: . -- Keegan (WMF) (talk) 06:15, 19 April 2015 (UTC)


text:
User talk:Captain panda

Welcome
Hello Captain panda, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. To get started, you may
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And don't forget to explore Wikiversity with the links to your left. Be bold, and see you around Wikiversity! --Countrymike 07:13, 3 January 2008 (UTC)

title: User talk:Captain panda


text:
User talk:Varun005~enwikiversity

Welcome
Hello Varun005, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. To get started, you may
 * Take a guided tour and learn to edit;
 * Explore our learning projects;
 * Browse our portals, schools, and research activities;
 * Read and help develop our community policies；or
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And don't forget to explore Wikiversity with the links to your left. Be bold, and see you around Wikiversity! --Countrymike 07:13, 3 January 2008 (UTC)

Your account will be renamed
Hello,

The developer team at Wikimedia is making some changes to how accounts work, as part of our on-going efforts to provide new and better tools for our users like cross-wiki notifications. These changes will mean you have the same account name everywhere. This will let us give you new features that will help you edit and discuss better, and allow more flexible user permissions for tools. One of the side-effects of this is that user accounts will now have to be unique across all 900 Wikimedia wikis. See the announcement for more information.

Unfortunately, your account clashes with another account also called Varun005. To make sure that both of you can use all Wikimedia projects in future, we have reserved the name Varun005~enwikiversity that only you will have. If you like it, you don't have to do anything. If you do not like it, you can pick out a different name.

Your account will still work as before, and you will be credited for all your edits made so far, but you will have to use the new account name when you log in.

Sorry for the inconvenience.

Yours, Keegan Peterzell Community Liaison, Wikimedia Foundation 00:11, 18 March 2015 (UTC)

Renamed
 This account has been renamed as part of single-user login finalisation. If you own this account you can |log in using your previous username and password for more information. If you do not like this account's new name, you can choose your own using this form after logging in: . -- Keegan (WMF) (talk) 06:24, 19 April 2015 (UTC)

title: User talk:Varun005~enwikiversity


text:
User talk:Myo minthein2000

Welcome
Hello Myo minthein2000, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. To get started, you may
 * Take a guided tour and learn to edit;
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And don't forget to explore Wikiversity with the links to your left. Be bold, and see you around Wikiversity! --Countrymike 07:14, 3 January 2008 (UTC)

title: User talk:Myo minthein2000


text:
User talk:Katydidn't

Welcome
Hello Katydidn't, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. To get started, you may
 * Take a guided tour and learn to edit;
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 * Browse our portals, schools, and research activities;
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And don't forget to explore Wikiversity with the links to your left. Be bold, and see you around Wikiversity! --Countrymike 07:14, 3 January 2008 (UTC)

title: User talk:Katydidn't


text:
User talk:Aytac Kadir Mutlu

Welcome
Hello Aytac Kadir Mutlu, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. To get started, you may
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Welcome Aytac, make sure to check out Category:Neuroscience. Countrymike 07:16, 3 January 2008 (UTC)

title: User talk:Aytac Kadir Mutlu


text:
User:Juandev/Endangered Plants

This is an incubator for the project called Endangered Plants.

title: User:Juandev/Endangered Plants


text:
User talk:Ashok Vignesh

Hello! I'm Ashok Vignesh.

title: User talk:Ashok Vignesh


text: Southeast Asian Languages/Bahasa Indonesia/Lesson:Counting


text: User:Palakmathur

title: User:Palakmathur


text:
User talk:Palakmathur

Welcome
Hello Palakmathur, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. To get started, you may
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And don't forget to explore Wikiversity with the links to your left. Be bold, and see you around Wikiversity! --JWS 14:00, 3 January 2008 (UTC)

title: User talk:Palakmathur


text:
Ivan Illich: Deschooling Society/Learning Webs

Notes for Chapter 6.

An Objection: Who Can Be Served by Bridges to Nowhere?

 * "Only hindsight will allow us to discover if the Great Cultural Revolution will turn out to have been the first successful attempt at deschooling the institutions of society". See also: Socialist Education Movement.

Question: Do we have to invent a conspiracy theory to account for the way schools function (and dis-function) or is it possible that schools are the natural result of unavoidable limitations arising from brick-and-mortar schooling for all?

General Characteristics of New Formal Educational Institutions

 * "A good educational system should have three purposes: it should provide all who want to learn with access to available resources at any time in their lives; empower all who want to share what they know to find those who want to learn it from them; and, finally, furnish all who want to present an issue to the public with the opportunity to make their challenge known....It should use modern technology to make free speech, free assembly, and a free press truly universal and, therefore, fully educational......Technology is available to develop either independence and learning or bureaucracy and teaching."

Question: Rather than looking for some kind of social revolution that would transform schooling, is it possible that new technology must come first? Can information technology change the function of bricks-and-mortar schools in a revolutionary way?

Four Networks
Can a community like Wikiversity provide elements of these "four networks"?
 * 1) "Educational Objects....made available to students" - Open Educational Resources
 * 2) "permit persons to list their skills" and "the conditions under which they are willing to serve as models for others who want to learn these skills" - Userboxes
 * 3) "a communications network which permits persons to describe the learning activity in which they wish to engage, in the hope of finding a partner for the inquiry" - Portal:Reading groups
 * 4) "Reference Services to Educators-at-Large" - participant lists


text:
Template:Atp/handouts

Handouts:

title: Template:Atp/handouts


text:
Template:Bcpm/prag/1

January

This template makes a link to the January key for Prague, and adds plant pages to Category:BCP/PRAGUE/1 and Category:BCP/Flora of the Czech Republic (it automatically adds ), for plants that have been recorded as flowering in January in Prague.

This template should only be used in the "Prague = " field of Bloom clock plant middle

title: Template:Bcpm/prag/1


text:
Bloom Clock/Keys/Prague/January

January

 * 1) All plants recorded in January

title: Bloom Clock/Keys/Prague/January


text:
Bloom Clock/Keys/Prague/January/All

The plants pictured below have been recorded as blooming during the month of January in Prague, Czech Republic.

last updated --Juan 15:45, 3 January 2008 (UTC) with 1 plant

title: Bloom Clock/Keys/Prague/January/All


text:
Category:BCP/PRAGUE/1

This category is for plants found flowering in January in Prague, Czech Republic.

title: Category:BCP/PRAGUE/1


text:
User:Anthonys

Stephen Anthony
*Indiana University *Instructional Systems Design *Profile first created Jan 2008 *for R626 Instructional Strategies and Tactics

title: User:Anthonys


text:
User talk:Anthonys

Welcome
Hello Anthonys, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. To get started, you may
 * Take a guided tour and learn to edit;
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And don't forget to explore Wikiversity with the links to your left. Be bold, and see you around Wikiversity! --JWSchmidt 17:33, 3 January 2008 (UTC)

subpages
Hello Anthony, what do you say on this ?

we could name the page
 * from: ID constructivist strategy 001
 * to: Topic:Designing a Constructivist Learning Environment

and put the subpages like this:
 * Topic:Designing a Constructivist Learning Environment/Project Description
 * Topic:Designing a Constructivist Learning Environment/Syllabus Description

so, everybody can see to where the subpages belong - also they can easily go back to the main page with a click (you can see then, when it is finished). Do you want me to do this for you ? Or you have other ideas ? Erkan Yilmaz ( Wikiversity:Chat, wiki blog ) 20:15, 19 February 2008 (UTC)
 * Done, see now here please: Topic:Designing a Constructivist Learning Environment. You can also do this with the "move"-button at the top of each page. More about subpages you can find e.g. here: Subpages.
 * If this is ok now with you, I delete the old pages which are only redirects now. Erkan Yilmaz ( Wikiversity:Chat, wiki blog ) 20:34, 19 February 2008 (UTC)
 * Please have a look here, Erkan Yilmaz uses the Wikiversity:Chat (try) 21:30, 2 April 2008 (UTC)

Image copyright problem with Image:ConstructivismIcon.png
Thanks for uploading Image:ConstructivismIcon.png. However, the image may soon be deleted unless we can determine the copyright holder and copyright status. The Wikimedia Foundation is very careful about the images included in Wikiversity because of copyright law (see Wikiversity' Copyright policy).

The copyright holder is usually the creator, the creator's employer, or the last person who was transferred ownership rights. Copyright information on images is signified using copyright templates. The three basic license types on Wikiversity are open content, public domain, and fair use. Find the appropriate template in Image copyright tags and place it on the image page like this:.

Please signify the copyright information on any other images you have uploaded or will upload. Remember that images without this important information or giving false information can be deleted by an administrator. If you have any questions, feel free to contact me, or ask them at Colloquim. Thank you. --Erkan Yilmaz uses the Wikiversity:Chat (try) 05:37, 17 April 2008 (UTC)
 * This is unfortunately the case also for all the other uploaded pictures, see here please:, Erkan Yilmaz uses the Wikiversity:Chat (try) 05:37, 17 April 2008 (UTC)

title: User talk:Anthonys


text:
Talk:Computer-aided design/Computer Aided Drafting

I would suggest to change this from Computer Aided Drafting to Computer Aided Design, to make it broader... I have a couple of basic tutorials about architecture modelling with blender (I'm writing more at the moment) that could fit well here. If anyone would like to have a look at them here and tell me if you find the idea interesting, I would be grateful.--Yorik 17:40, 3 January 2008 (UTC)
 * Wow, nice stuff. Feel free to explore how to "fit" your resources in here. Remember, Wikiversity welcomes links to good learning resources at other websites, so do not feel like you have to move resources to this website....often a link to the original resource is just fine. --JWSchmidt 17:45, 3 January 2008 (UTC)


text:
User talk:Yorik

Welcome
Hello Yorik, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. To get started, you may
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 * Browse our portals, schools, and research activities;
 * Read and help develop our community policies；or
 * Chat with other Wikiversitans on #wikiversity-en.

And don't forget to explore Wikiversity with the links to your left. Be bold, and see you around Wikiversity! --JWSchmidt 17:46, 3 January 2008 (UTC)

merge
Hello, also a warm welcome by me. The merge you proposed was done. Some content was added in a subsection "Other ideas to implement on this page". Would be nice, if you can somehow integrate this. Thanks for your help, Erkan Yilmaz uses the Chat (try) 10:28, 20 July 2008 (UTC)

nothing specific
... I guess you will know best what you like and where you can be useful here at WV. Do something you want, that makes sure, that you stay here long time (this is what we want).

Just a small notice, if you like you can use instead: Architecture this syntax: Architecture This results in the same, only that it shows as internal link, so others can differentiate better which links are really external ones. Have a nice evening and drop by teh chat if you want one day, Erkan Yilmaz uses the Chat (try) 16:28, 21 July 2008 (UTC)
 * I'm glad, you are back again. If you need some help, tell me. Bye for now, Erkan Yilmaz uses the Chat (try) 21:17, 25 August 2008 (UTC)

title: User talk:Yorik


text:
User talk:Morenus~enwikiversity

Welcome
Hello Morenus, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. To get started, you may
 * Take a guided tour and learn to edit;
 * Explore our learning projects;
 * Browse our portals, schools, and research activities;
 * Read and help develop our community policies；or
 * Chat with other Wikiversitans on #wikiversity-en.

And don't forget to explore Wikiversity with the links to your left. Be bold, and see you around Wikiversity! --JWSchmidt 20:36, 3 January 2008 (UTC)

Your account will be renamed
Hello,

The developer team at Wikimedia is making some changes to how accounts work, as part of our on-going efforts to provide new and better tools for our users like cross-wiki notifications. These changes will mean you have the same account name everywhere. This will let us give you new features that will help you edit and discuss better, and allow more flexible user permissions for tools. One of the side-effects of this is that user accounts will now have to be unique across all 900 Wikimedia wikis. See the announcement for more information.

Unfortunately, your account clashes with another account also called Morenus. To make sure that both of you can use all Wikimedia projects in future, we have reserved the name Morenus~enwikiversity that only you will have. If you like it, you don't have to do anything. If you do not like it, you can pick out a different name.

Your account will still work as before, and you will be credited for all your edits made so far, but you will have to use the new account name when you log in.

Sorry for the inconvenience.

Yours, Keegan Peterzell Community Liaison, Wikimedia Foundation 23:44, 17 March 2015 (UTC)

Renamed
 This account has been renamed as part of single-user login finalisation. If you own this account you can |log in using your previous username and password for more information. If you do not like this account's new name, you can choose your own using this form after logging in: . -- Keegan (WMF) (talk) 06:16, 19 April 2015 (UTC)

title: User talk:Morenus~enwikiversity


text: File:Nornal.png

title: File:Nornal.png


text: File:Abnormal.png

title: File:Abnormal.png


text:
Talk:Cytogenetics

What is normal?
The following images show mitotic figures in cultured animal cells. I made some guesses about what might be normal mitotic figures and abnormal situations. Any expert commentary is welcome. --JWS 21:07, 3 January 2008 (UTC)

title: Talk:Cytogenetics


text:
Anatomy and physiology of the thyroid gland

The thyroid is one of the largest endocrine glands in the body. It controls how quickly the body burns energy, makes proteins, and how sensitive the body should be to other hormones.

Anatomy
The thyroid is composed of two pear shaped lobes which extend from the thyroid cartilage to the 6th tracheal ring on the anterior side of the neck. It lies over the trachea and is covered by layers of pretracheal fascia (allowing it to move), muscle and skin. The two lobes are joined by the isthmus which overlies tracheal rings 2, 3 and 4. The thyroid may enlarge substantially during pregnancy and when affected by a variety of diseases.

Surface anatomy
The normal thyroid gland is easily palpable. Palpation is carried out from behind using the digits to feel for the cricoid cartilage and for the 1st tracheal ring directly below it. The isthmus of the thyroid overlies the 2nd through the fourth tracheal rings, to which the pretracheal fascia (a fibrous sheath that contains the thyroid and allows it to glide smoothly over the nearby contents) firmly attaches through suspensory ligaments (extensions of the fascia). This attachment allows the thyroid to move with the larynx during swallowing, an important fact in palpating the thyroid as it is appropriate to ask the patient to sip a glass of water while palpating the gland, as to allow the inferior portion to be better felt when it elevates with the larynx.

Depending on the state of the thyroid the superior pole is commonly located at the level of the cricothyroid ligament (membrane). While the inferior poles are often difficult to palpate as the sternocleidomastoid relatively speaking) lies just lateral. Two other muscles overlie the majority of the lateral lobes – the sternohyoid and deeper the sternothyroid – however these muscles are small and flat and should not interfere with palpation if the patient is asked to relax the neck (nevertheless the sternothyroid is important in limiting the spread of the thyroid when enlarged).


text:
Materials Science and Engineering/List of Topics/Engineered Glasses

Factors that Enhance Glass formation
 * High viscosity of liquid
 * Complex crystal structure
 * High cooling rate

Difficult to find proper lattice sites

Particular form of glass: silica
 * Silica is inorganic and covalent

In crystalline silicon, all the atoms are the same
 * In silica, there is silicon and oxygen that form long chains and is polymeric
 * The molecules entangle and must disentangle
 * Drop temperature, bonds must twist
 * Quick solidification - fail to achieve crystallinity
 * Quench in disorder
 * Silicon: all four bonds are fixed in space and fully specified
 * Oxygen: bonds free to rotate and there is one degree of freedom

Perfect alignment - create crystalline structure

X-ray spectra
 * Crystobalite - several peaks
 * Amorphous silica - one peak
 * The peak is due to short-range order
 * There is no long-range order

Energetics of glass formation - when are more bonds formed?
 * Crystalline solid is at lower energy
 * There is a higher bond density
 * More compact structure
 * More bonds per unit volume
 * Volume is a macroscopic measure of disorder

Volume as function of temperature
 * Liquid turns to solid and contracts
 * Most substances pack more tightly in solid state
 * Volume decreases as cool
 * Jump to liquid state

Mercury in glass bulb - change in liquid unit volume is larger than solid

A glass is formed by cooling so quickly that act as liquid below melting point
 * Glass transition temperature
 * Viscosity is highly dependent on temperature
 * Knee in curve is function of cooling rate
 * When cool slowly, there is more time of the constituents of the system to rearrange position
 * The excess volume is not as large in comparison to crystal

Solidification is determined by knee in curve of volume versus temperature
 * Coefficient of thermal expansion is less

Difference between solidication to form crystal and form glass
 * Crystal - abrupt change in V versus T
 * Glass - no abrupt change in V versus T at glass transition temperature

Liquid to crystalline solid
 * Melting point independent of cooling rate

Glass transition
 * Supercooled liquid - cooled below melting point
 * The substance is a glassy solid
 * $$T_g$$ is function of the cooling rate
 * More or less free volume determined by cooling rate

There are other systems in addition to silica
 * Other glass forming oxides:
 * $$GeO_2$$
 * $$B_2O_3$$: Borate
 * $$P_2O_5$$
 * $$As_2O_5$$
 * $$Sb_2O_5$$
 * Volume of glass far in excess between glass and crystal
 * Form covalent bonds of metal to metal via bridging oxygen
 * Three dimensional covalent bonds

Properties of oxide glass
 * Chemically inert
 * Electrically insulating
 * Strong bonds hold electrons
 * Mechanically brittle
 * Very directional, no possibility of glide
 * Optically transparent
 * Strong covalent bonds, energy levels far part
 * Visually arresting
 * Don't form sharp edges
 * Color from dopant
 * High melting temperature

Source:

MIT - Course 3.091 - Professor Sadoway - Fall 2004 - Lecture 21
 * Content accessed through MIT OpenCourseWare (http://ocw.mit.edu/)


text:
Materials Science and Engineering/List of Topics/Rutherford Model of the Atom

The Rutherford model or planetary model was a model of the atom devised by Ernest Rutherford. Rutherford directed the famous Geiger-Marsden experiment in (1909), which suggested to Rutherford's analysis (1911) that the Plum pudding model (of J. J. Thomson) of the atom was incorrect. Rutherford's new model for the atom, based on the experimental results, had a number of essential modern features, including a relatively high central charge concentrated into a very small volume in comparison to the rest of the atom.

Experimental basis for the model
In the Geiger-Marsden experiment at Rutherford's laboratory, alpha particles were used as a probe into atomic structure by being allowed to pass through a thin piece of gold foil, then detected. Rutherford predicted that all of the particles would pass through the foil, or be deflected slightly. This is indeed what happened most of the time, but a few particles, 1 in 8000, bounced unexpectedly nearly straight back toward the source. This supported the hypothesis that atoms have a dense region containing most of their mass, and associated with a highly concentrated electric field (probably positive in nature), instead of spread-out positive or negative field. Rutherford thought it likely, on purely symmetric and aesthetic grounds, that such a region of dense charge and mass would be located in the atom's center. Such a region would then form a sort of atomic core.

In 1911, Rutherford came forth with his own physical model for subatomic structure, as an interpretation for the unexpected experimental results. In it, the atom is made up of a central charge (this is the modern atomic nucleus, though Rutherford did not use the term "nucleus" in his paper) surrounded by a cloud of orbiting electrons. In this 1911 paper, Rutherford only commits himself to a small central region of very high positive or negative charge in the atom, but uses the following language for pictorial purposes:

"For concreteness, consider the passage of a high speed a particle through an atom having a positive central charge N e, and surrounded by a compensating charge of N electrons."

From purely energetic considerations of how far alpha particles of known speed would be able to penetrate toward a central charge of 100 e, Rutherford was able to calculate that the radius of his gold central charge would need to be less (how much less could not be told) than 3.4 x 10-14 metres (the modern value is only about a fifth of this). This was in a gold atom known to be 10-8 metres or so in radius--- a very surprising finding, as it implied a strong central charge less than 1/3000th of the diameter of the atom.

The Rutherford model did not attribute any structure to the orbits of the electrons themselves, though it did mention the atomic model of Hantaro Nagaoka, in which the electrons are arranged in one or more rings (this is the only previous atomic model mentioned in Rutherford's 1911 paper).

The Rutherford paper suggested that the central charge of an atom might be "proportional" to its atomic mass in hydrogen mass units (roughly 1/2 of it, in Rutherford's model). For gold, this mass number is 197 (not then known to great accuracy) and was therefore modeled by Rutherford to be possibly 196. However, Rutherford did not attempt to make the direct connection of central charge to atomic number, since gold's place on the periodic table was known to be about 79, and Rutherford's more tentative model for the structure of the gold nucleus was 49 helium nuclei, which would have given it a mass of 196 and charge of 98. This differed enough from gold's "atomic number" (at that time merely its place number in the periodic table) that Rutherford did not formally suggest the two numbers might be exactly the same.

Successor model
The Rutherford model of the atom was soon superseded by the Bohr atom, which used some of the early quantum mechanical results to give locational structure to the behavior of the orbiting electrons, confining them to certain circular (and later eliptical) planar orbits. In the Bohr model, expanding on the work of Henry Moseley, the central charge was identified as being directly connected with the atomic number (that is, the element's place on the periodic table). Since the Bohr model is an improvement on the Rutherford model in this and other ways, some sources combine the two, referring to the Bohr model as the Rutherford-Bohr model. However, even an atom with a core containing an atomic number of charges was the work of a number of men, including those mentioned, and also lesser known workers such as Antonius Van den Broek.

The Rutherford model was important because it essentially proposed the concept of the nucleus, although this word is not used in the paper. What Rutherford notes as the (probable) concomitant of this results, is a "concentrated central charge" in the atom: "Considering the evidence as a whole, it seems simplest to suppose that the atom contains a central charge distributed through a very small volume, and that the large single deflexions are due to the central charge as a whole, and not to its constituents." The central charge containing most of the atom's positive charge, invariably later become associated with a concrete structure, the atomic nucleus.

After the Rutherford model and its confirmation in the experiments of Henry Moseley and its theoretical description in the Bohr model of the atom, the study of the atom branched into two separate fields, nuclear physics, which studies the nucleus of the atom, and atomic physics which studies atom's electronic structure.


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User:Jazzbaby 12

Hardy har har....well, this is my first time creating a wiki account and I hope it works out. I'm physco and kinda crazy--at least that's what my friends say. :) My email address is jazzbaby_12@yahoo.com if you want to email me. See ya around.

title: User:Jazzbaby 12


text:
Materials Science and Engineering/List of Topics/Bohr Model of the Atom

In atomic physics, the Bohr model depicts the atom as a small, positively charged nucleus surrounded by electrons that travel in circular orbits around the nucleus — similar in structure to the solar system, but with electrostatic forces providing attraction, rather than gravity. This was an improvement on the earlier cubic model (1902), the plum-pudding model (1904), the Saturnian model (1904), and the Rutherford model (1911). Since the Bohr model is a quantum-physics based modification of the Rutherford model, many sources combine the two, referring to the Rutherford-Bohr model.

Introduced by Niels Bohr in 1913, the model's key success lay in explaining the Rydberg formula for the spectral emission lines of atomic hydrogen; while the Rydberg formula had been known experimentally, it did not gain a theoretical underpinning until the Bohr model was introduced. Not only did the Bohr model explain the reason for the structure of the Rydberg formula, but it provided a justification for its empirical results in terms of fundamental physical constants.

The Bohr model is a primitive model of the hydrogen atom. As a theory, it can be derived as a first-order approximation of the hydrogen atom using the broader and much more accurate quantum mechanics, and thus may be considered to be an obsolete scientific theory. However, because of its simplicity, and its correct results for selected systems (see below for application), the Bohr model is still commonly taught to introduce students to quantum mechanics, before moving on to the more accurate but more complex valence shell atom. A related model was originally proposed by Arthur Erich Haas in 1910, but was rejected.

History
In the early 20th century, experiments by Ernest Rutherford established that atoms consisted of a diffuse cloud of negatively charged electrons surrounding a small, dense, positively charged nucleus. Given this experimental data, it was quite natural for Rutherford to consider a planetary model for the atom, the Rutherford model of 1911, with electrons orbiting a sun-like nucleus. However, the planetary model for the atom has a difficulty. The laws of classical mechanics, specifically the Larmor formula, predict that the electron will release electromagnetic radiation as it orbits a nucleus. Because the electron would be losing energy, it would gradually spiral inwards and collapse into the nucleus. This is a disaster, because it predicts that all matter is unstable.

Also, as the electron spirals inward, the emission would gradually increase in frequency as the orbit got smaller and faster. This would produce a continuous smear, in frequency, of electromagnetic radiation. However, late 19th century experiments with electric discharges through various low-pressure gasses in evacuated glass tubes had shown that atoms will only emit light (that is, electromagnetic radiation) at certain discrete frequencies.

To overcome this difficulty, Niels Bohr proposed, in 1913, what is now called the Bohr model of the atom. He suggested that electrons could only have certain motions:
 * 1) The electrons travel in orbits that have discrete Quantization (physics)|quantized momenta, and therefore quantized speeds and energies. That is, not every orbit is possible but only certain specific ones, at certain specific distances from the nucleus.
 * 2) The electrons do not continuously lose energy as they travel. They can only gain and lose energy by jumping from one allowed orbit to another.

The significance of the Bohr model is that it states that the laws of classical mechanics do not apply to the motion of the electron about the nucleus. Bohr proposed rather that a new kind of mechanics, or quantum mechanics, describes the motion of the electrons around the nucleus. This model of electrons traveling in quantized orbits was extended into a matrix mechanics|more accurate model of electron motion about a dozen years later by Werner Heisenberg.Schrödinger equation|Another form of the same theory, modern quantum mechanics, was discovered by the Austrian physicist Erwin Schrödinger independently and by different reasoning.

Other points are:

 * 1) When an electron makes a jump from one orbit to another, the energy difference is carried away (or supplied) by a single quantum of light (called a photon) which has an energy equal to the difference in energy between the two orbits.
 * 2) The frequency of the emitted photon is the classical orbit frequency, since photon emission correspondence principle|corresponds to classical emission of radiation. Since there are two orbits involved in emission, this is only exact when both orbits have nearly the same frequency, and this holds only when the orbits are large.

Since the frequency of a photon is proportional to its energy, rule 2 allowed Bohr to calculate the gap in energy between levels--- the level spacing is equal to Planck's constant divided by the classical orbit period. Stepping down orbit by orbit, he found that the angular momentum changed by $$h/2\pi$$ at every step.

So he proposed that the angular momentum L is quantized according to the rule
 * $$ L = n \cdot \hbar = n \cdot {h \over 2\pi} $$

where n = 1,2,3,… and is called the principal quantum number, and h is Planck's constant.

The lowest value of n is 1. This corresponds to a smallest possible radius of 0.0529 nm. This is known as the Bohr radius. Once an electron is in this lowest orbit, it can get no closer to the proton.

Bohr's condition, that the angular momentum is an integer multiple of $$\scriptstyle\hbar$$ was later reinterpreted by DeBroglie as a standing wave condition: the electron is described by a wave and a whole number of wavelengths must fit along the circumference of the electron's orbit.

 * $$n \lambda = 2 \pi r\,$$

Substituting DeBroglie's wavelength reproduces Bohr's rule. Bohr justified his rule by appealing to the correspondence principle, without providing a wave interpretation.

Source:

Wikipedia, "Bohr model"


text:
Materials Science and Engineering/List of Topics/De Broglie, Heisenberg, and Schrodinger

de Broglie
In physics, the de Broglie hypothesis is the statement that all matter (any object) has a wave-like nature (wave-particle duality). The de Broglie relations show that the wavelength is inversely proportional to the momentum of a particle and that the frequency is directly proportional to the particle's kinetic energy. The hypothesis was advanced by Louis de Broglie in 1924 in his PhD thesis; he was awarded the Nobel Prize for Physics in 1929 for this work, which made him the first person to receive a Nobel Prize on a PhD thesis.

Historical context
After strides made by Max Planck (1858-1947) and Albert Einstein (1879-1955) in understanding the behavior of electrons and what would be known as quantum physics, Niels Bohr (1885-1962) began (among other things) trying to explain how electrons behave. He came up with new fundamental ideas about electrons and mathematically derived the Rydberg equation, an equation that was discovered only through trial and error. This equation explains the energy|energies of the light emitted when hydrogen gas is compressed and electrified (similar to neon signs, but with hydrogen in this case). Unfortunately, his model only worked for the hydrogen-atom-configuration, but his ideas were so revolutionary that they broke up the classical view of electrons' behavior and paved the way for fresh new ideas in what would become quantum physics and quantum mechanics.

Louis de Broglie (1892-1987) tried to expand on Bohr's ideas, and he pushed for their application beyond hydrogen. In fact he looked for an equation which could explain the wavelength characteristics of all matter. His equation was not proved experimentally until a few years later. Nevertheless, his hypothesis would hold true for both electrons and for everyday objects. In de Broglie's equation an electron's wavelength will be a function of Planck's constant ($$6.63 x 10^{-34}$$ joule-seconds) divided by the object's momentum (nonrelativistically, its mass multiplied by its velocity). When this momentum is very large (relative to Planck's constant), then an object's wavelength is very small. This is the case with every-day objects, such as a person. Given the enormous momentum of a person compared with the very tiny Planck constant, the wavelength of a person would be so small (on the order of $$10^{-35}$$ meters or smaller) as to be undetectable by any current measurement tools. On the other hand, many small particles (such as typical electrons in everyday materials) have a very low momentum compared to macroscopic objects. In this case, the de Broglie wavelength may be large enough that the particle's wave-like nature gives observable effects.

The wave-like behavior of small-momentum particles is analogous to that of light. As an example, electron microscopes use electrons, instead of light, to see very small objects. Since electrons typically have a larger momentum than photons, their de Broglie wavelength will be smaller, resulting in a greater spatial resolution.

The de Broglie relations
The first de Broglie equation relates the wavelength $$\lambda$$ to the particle momentum $$~p~$$ as

 * $$\lambda = \frac{h}{p} = \frac {h}{\gamma mv} = \frac {h}{mv} \sqrt{1 - \frac{v^2}{c^2}}$$

where $$~h~$$ is Planck's constant,  $$~m~$$ is the particle's rest mass, $$~v~$$ is the particle's velocity, $$~\gamma~$$ is the Lorentz factor, and $$~c~$$ is the speed of light in a vacuum.

The greater the energy, the larger the frequency and the shorter (smaller) the wavelength. Given the relationship between wavelength and frequency, it follows that short wavelengths are more energetic than long wavelengths. The second de Broglie equation relates the frequency of the wave associated to a particle to the total energy of the particle such that

 * $$f = \frac{E}{h} = \frac{\gamma\,mc^2}{h} = \frac {1}{\sqrt{1 - \frac{v^2}{c^2}}} \cdot \frac{mc^2}{h}$$

where $$~f~$$ is the frequency and $$~E~$$ is the total energy. The two equations are often written as

 * $$p = \hbar k$$
 * $$E = \hbar \omega$$

where $$~\hbar=h/(2\pi)~$$ is the reduced Planck's constant (also known as Dirac's constant, pronounced "h-bar"), $$~k~$$ is the wavenumber, and $$~\omega~$$ is the angular frequency.

See the article on group velocity for detail on the argument and derivation of the de Broglie relations.

Elementary Particles
In 1927 at Bell Labs, Clinton Davisson and Lester Germer fired slow-moving electrons at a crystalline nickel target. The angular dependence of the reflected electron intensity was measured, and was determined to have the same diffraction pattern as those predicted by Bragg for X-Rays. Before the acceptance of the de Broglie hypothesis, diffraction was a property that was thought to be only exhibited by waves. Therefore, the presence of any diffraction effects by matter demonstrated the wave-like nature of matter. When the de Broglie wavelength was inserted into the Bragg condition, the observed diffraction pattern was predicted, thereby experimentally confirming the de Broglie hypothesis for electrons.

This was a pivotal result in the development of quantum mechanics. Just as Arthur Compton demonstrated the particle nature of light, the Davisson-Germer experiment showed the wave-nature of matter, and completed the theory of wave-particle duality. For physicists this idea was important because it means that not only can any particle exhibit wave characteristics, but that one can use wave equations to describe phenomena in matter if one uses the de Broglie wavelength.

Since the original Davisson-Germer experiment for electrons, the de Broglie hypothesis has been confirmed for other elementary particles.

Neutral Atoms
Experiments with Fresnel diffraction and specular reflection of neutral atoms confirm the application of the De Broglie hypothesis to atoms, i.e. the existence of atomic waves which undergo diffraction, interference and allow quantum reflection by the tails of the attractive potential. This effect has been used to demonstrate atomic holography, and it may allow the construction of an atom probe imaging system with nanometer resolution. The description of these phenomena is based on the wave properties of neutral atoms, confirming the de Broglie hypothesis.

Waves of Molecules
Recent experiments even confirm the relations for molecules and even macromolecules, which are normally considered too large to undergo quantum mechanical effects. In 1999, a research team in Vienna demonstrated diffraction for molecules as large as fullerenes.

In general, the De Broglie hypothesis is expected to apply to any well isolated objects. it was a very long process

Heisenberg
As a student, Heisenberg met Niels Bohr in Göttingen in 1922. A fruitful and life long collaboration developed between the two.

He invented matrix mechanics, the first formalization of quantum mechanics in 1925, which he developed with the help of Max Born and Pascual Jordan. His uncertainty principle, developed in 1927, states that the simultaneous determination of two paired quantities, for example the position and momentum of a particle, has an unavoidable uncertainty. Together with Bohr, he formulated the Copenhagen interpretation of quantum mechanics.

He received the Nobel Prize in physics in for the creation of quantum mechanics, the application of which has, inter alia, led to the discovery of the allotropic forms of hydrogen".

In the late 1920s and early '30s, Heisenberg collaborated with Wolfgang Pauli, and along with Paul Dirac, developed an early version of quantum electrodynamics. However, at the time, nobody could get rid of the infinities plaguing the theory, and it was only after World War II that a technique called renormalization was invented to take care of the infinities.

After the discovery of the neutron by James Chadwick in 1932, Heisenberg proposed the proton-neutron model of the atomic nucleus and used it to explain the nuclear spin of isotopes.

During the early days of the Nazi regime in Germany, Heisenberg was harassed as a "White Jew" for teaching theories that Albert Einstein, a prominent Jew, had conceived. Teaching these theories was in contradiction to the Nazi-sanctioned Deutsche Physik movement. After a character investigation that Heisenberg himself instigated and passed, SS chief Heinrich Himmler banned any further political attacks on the physicist.

Schrodinger
Erwin Rudolf Josef Alexander Schrödinger (August 12, 1887 – January 4, 1961) was an Austrian - Irish physicist who achieved fame for his contributions to quantum mechanics, especially the Schrödinger equation, for which he received the Nobel Prize in 1933. In 1935, after extensive correspondence with personal friend Albert Einstein, he proposed the Schrödinger's cat thought experiment.

Schrodinger Equation
In physics, the Schrödinger equation, proposed by the Austrian physicist Erwin Schrödinger in 1926, describes the space- and time-dependence of quantum mechanical systems. It is of central importance in non-relativistic quantum mechanics, playing a role for microscopic particles analogous to Newton's second law in classical mechanics for macroscopic particles. Microscopic particles include elementary particles, such as electrons, as well as systems of particles, such as atomic nuclei. Macroscopic particles vary in mass from cells to the galactic superclusters. and he has pretty shoes

Source:

Wikipedia