Wikidata talk:WikiProject Physics

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Classification of isotope

I was wondering how we can link the different isotope between them. Using instance of (P31) we can create an item QXXX represent an element with X protons then for each isotope we create another item QYYY which is a instance of/subclass of the main item. QXXX has no physical reality but is the conceptual element. What do you think ? Snipre (talk) 11:44, 16 October 2013 (UTC)

Once number datatype is available we could make queries for "all items with same number of protons". I am not sure if a separate property would be needed. --Tobias1984 (talk) 12:13, 16 October 2013 (UTC)

There is no new property there. TomT0m (talk)

This is the way to go, 1H is a subclass of hydrogen as any 1h atom is an hydrogen atom, and 1H is an instance of isotope of hydrogen (Q466603). TomT0m (talk) 16:34, 16 October 2013 (UTC)

Sounds good. First we need to get all the isotopes in order and get rid of all the duplicates. --Tobias1984 (talk) 17:43, 16 October 2013 (UTC)

Ok, so with the list of current items

• hydrogen (Q556)
• isotope of hydrogen (Q466603)
• hydrogen atom (Q6643508)
• deuterium (Q102296)
• tritium (Q54389)

What kind of links can we create for them ? Snipre (talk) 19:37, 16 October 2013 (UTC)

There are more already more items for hydrogen: Wikidata:Physics_task_force/List_of_nuclides --Tobias1984 (talk) 19:49, 16 October 2013 (UTC)

@Tobias : not first, adding the statements is actually helpful in curating the datas and find duplicates ;) . TomT0m (talk) 08:50, 17 October 2013 (UTC)

Ok both :) Because Dutch Wiki has a lot of isotope-items but we have to find them in order not to create hundreds of duplicates. And adding the statements can be done in one run ;) --Tobias1984 (talk) 09:03, 17 October 2013 (UTC)

protium

Hi! should we use said to be the same as (P460) for hydrogen atom (Q6643508) and protium (Q15406064) ? Some languages as fr.Wikipedia have two articles. gangLeri לערי ריינהארט (talk) 12:07, 3 May 2014 (UTC)

@לערי_ריינהארט: I think if there are two pages then hydrogen atom refers to the properties of the chemical element with one proton and one electron, and protium refers to the properties of the nuclide with one proton. I wouldn't use said to be the same as (P460) for this relationship. Tobias1984 (talk) 15:03, 3 May 2014 (UTC)

@Tobias1984: Is there a property to "show" that there are more items describing different "views" of the same "object/subject". It could be used also for WD items starting with "outline of ..." (many exists at en.Wikipedia), some "history of", and other similar places where "main article" is used (also mainly at en.Wikipedia). Such situations could occur also at descriptions relevant to a specific culture; one may expect more articles in the corresponding language then in the 250+ other languages. לערי ריינהארט (talk) 15:26, 3 May 2014 (UTC)

Evaporiative cooling (machine and ultra-cold matter physics)

I found three wikidata entries: magnetic evaporative cooling (Q6731539), evaporative cooler (Q1896787) and Q2514471. They seems to describe either the technical devices (like air-conditioner) or the ultra-cold matter aspect (btw: both rely on the same physical principle). So three wikidata entries and two subjects. Any suggestions what to do? Merging? Merging what to what? I already moved the german articles. --Nobelium (talk) 18:26, 12 August 2014 (UTC)

@Nobelium: I think we should move this discussion to Wikidata:WikiProject Physics. You are more than welcome to join if you like to edit physic-topics. --Tobias1984 (talk) 22:34, 12 August 2014 (UTC)

@Nobelium: I would merge Q2514471 into evaporative cooler (Q1896787). --Petermahlzahn (talk) 12:09, 13 August 2014 (UTC)

I do not speak Danish nor Norwegian, so I do not know about evaporative cooler (Q1896787). If you are sure both items refer to the same subject so I will merge them quickly. Pamputt (talk) 21:09, 13 August 2014 (UTC)

Me too. But what I tried is to catch up a few buzz word. I agree to move the Norwegian (nynorsk) to evaporative cooler (Q1896787) (I'll do so in the next days). But I'm still unsure about the Danish article. There is the BEC (Bose-Einstein Condensate) mentioned which is - as far as I know - only reachable through the evaporative cooling and therefore belongs to magnetic evaporative cooling (Q6731539)? Concerning the magnetic in the description: there is a suggestion on the english article to rename the article Magnetic evaporative cooling to Evaporative cooling (atomic physics) (Talk:Magnetic_evaporative_cooling)

@Pamputt: Je lis que francais est ton langue maternelle: Am I right that Refroidissement par évaporation fits better to magnetic evaporative cooling (Q6731539)? --Nobelium (talk) 20:26, 14 August 2014 (UTC)

P1127

Hello, isospin z-component (P1127) was created recently. I am not sure to understand what this property means. Does it refer to weak isospin (Q678322)? Could you give any example how to use it? Pamputt (talk) 08:24, 24 August 2014 (UTC)

@Pamputt: It is a field used by the German-wiki infobox for particles: de:Vorlage:Infobox Teilchen. As I am not a particle physicist, I can only refer you to the English-wiki description:

"Isospin is described by two quantum numbers: I, the total isospin, and I3, an eigenvalue of the Iz projection for which flavor states are eigenstates, not an arbitrary projection as in the case of spin. In other words, each I3 state specifies certain flavor state of a multiplet."

(en:Isospin#Isospin symmetry). For a Proton the infobox says 1/2 and +1/2 for the z-component. And for a Neutron it is 1/2 and -1/2 for the z-component. Maybe @Svebert: can take a look at the property and add a better documentation. -Tobias1984 (talk) 08:42, 24 August 2014 (UTC)

Fundamental interactions

Hi, just catched a discussion which is in the topic of this project on Emw's talkage with Laddo. I suggest it continues here. It might interest Jibe-b who seems to be interested on Physics ontology (notif Tobias1984) and just arrived a few hours after the beginning of this conversation, what a coincidence !

The discussion is on fundamental force like gravity Help:Classification and took place here. I suggest we continue it here. TomT0m ^(talk) 10:56, 22 September 2014 (UTC)

As I mentioned on Emw's talk page, I personally prefer gravity (Q11412) instance of fundamental interaction (Q104934), but I don't have a strong opinion on this topic, as long as all fundamental interactions and the constraints are coherent. As TomT0m suggested, I fixed fundamental interaction (Q104934) that of course should have been subclass of interaction (Q52948) from the start. LaddΩ chat ;) 02:30, 23 September 2014 (UTC)

@Laddo: It's not really consistent to have fundamental interaction (Q104934) as a subclass of interaction but

⟨ gravity (Q11412) ⟩ instance of (P31) ⟨ fundamental interaction (Q104934) ⟩

.

Any instance of interaction is the earth is attracted by the sun or the bond of some specific atoms in a Uranium bar in a nuclear power plant. Then gravitation's interaction are a subset of all interaction, my first example beetween the earth and the sun is in this class, the second is not.

'instance of (P31) links elements of the set of instances to the class (the set of instances) itself. subclass of (P279) links set of instances to set of instances. By saying gravitation instance of (P31) fundamental interaction and fundamental interaction subclass of interaction you would break this rule per my example : gravitation has a lot of instances, and its instances would also be instances of fundamental interaction.

It's different if fundamental interaction is not a subclass of interaction, by a class of interaction patterns, or a class of laws of physics who describe interactions. Then the fundamental interaction class would be a class of physical laws, and gravity would be an instance of it. Gravity would still be a class of interaction, and its instances would be interactions that follows the gravitation laws, but not a subclass of fundamental interaction as interactions are not physical laws. As I said in Emw's talkpage, we still can use both model with two items <fundamental interaction> for the set of concrete iterations that follows any of the fundamental interaction laws, and <fundamental interaction laws> for the class of all fundamental interaction, with

⟨ Gravity ⟩ instance of (P31) ⟨ fundamental interaction laws/model/pattern ⟩

...

This seems justified because I can see a link beetween classes expressions in OWL language which can say stuff like woman are humans with a female sex and physical laws : gravity interaction are interaction that follows the gravity interaction laws.

The class expression is used such that all instance of the human class with a female sex property will be automatically (intance of) women. But in Wikidata, we can also talk of the laws of physics as object. And the laws in question can form a class of laws. If the law is the equivalent of a class expression, then this means we can use class expressions as instances in Wikidata, which breaks the principle type–token distinction (Q175928) but I don't think it is a problem. TomT0m ^(talk) 08:51, 23 September 2014 (UTC)

Launch of WikiProject Wikidata for research

Hi, this is to let you know that we've launched WikiProject Wikidata for research in order to stimulate a closer interaction between Wikidata and research, both on a technical and a community level. As a first activity, we are drafting a research proposal on the matter (cf. blog post). It would be great if you would see room for interaction! Thanks, --Daniel Mietchen (talk) 01:33, 9 December 2014 (UTC)

Units are available

From Wikidata:Project_chat#Units_are_live.21_.5Co.2F, it is now possible to create properties for quantities with units. Do you know if we have already open requests to ask the creation of some of the properties given on Wikidata:WikiProject_Physics? Pamputt (talk) 05:21, 10 September 2015 (UTC)

@Pamputt: We have a list of pending properties here that can be created without further discussion (although one has to make sure it meets the standards we have today): Wikidata:Property_proposal/Pending/2 - I will try to go through some of the properties soon. --Tobias1984 (talk) 17:30, 11 September 2015 (UTC)

@Tobias1984: I propose you to put again the pending proposals in the Natural science proposal page for several days or one week. It is good to see if some people can add some comments: after 2 years we have a better experience and even if the proposals are the results of a consensus, the definition of the use of the properties can be better defined from the begining in order to reduce bad use later. Snipre (talk) 17:46, 11 September 2015 (UTC)

@Snipre: Good idea. I will move some of the science properties back to the proposal page. But it will take some time going through that list and sorting out the mess :) --Tobias1984 (talk) 17:55, 11 September 2015 (UTC)

List of new properties

• density (P2054)
• electrical conductivity (P2055)
• specific heat capacity (P2056)
• luminosity (P2060)
• mass (P2067)
• thermal conductivity (P2068)
• temperature (P2076)
• under pressure (P2077)
• melting point (P2101)
• boiling point (P2102)
• decomposition point (P2107)
• sublimation temperature (P2113)
• half-life (P2114)
• kinematic viscosity (P2118)
• radius (P2120)

Automatic tables

Especially for smaller wikis generating automatic tables would be really helpful to provide up to date information with little maintenance work: Wikidata:WikiProject Physics/List of Elements. --Tobias1984 (talk) 17:28, 11 September 2015 (UTC)

Great idea - I tried this: Wikidata:WikiProject Physics/AutoList of Nuclides - though I seem to get Listeria "no template errors"? Also a problem with display of units for half-life. What would be really nice would be a chart of the nuclides tool, like the Periodic Table tool. ArthurPSmith (talk) 13:55, 2 October 2015 (UTC)

@ArthurPSmith: The list seems to work now. Great idea with having a nuclide chart. @Ricordisamoa: Could you help us with that? --Tobias1984 (talk) 21:12, 2 October 2015 (UTC)