Why is there no Q&A category for subfield X?

Question

Hello everyone!

I am a theoretical plasma physicist who just recently learned about this site. Having been a regular user of mathoverflow and mathstackexchange for the past year, I am very excited about the benefits this site could bring to my field. However, there is currently no Q&A category for plasma physics. How does one go about changing this? I should mention that there already are questions that should be categorized as plasma physics, e.g. here and here.

More generally, one could ask this same question but with "plasma physics" replaced by "biophysics" or any other major physics subfield that is not currently represented in the Q&A categories.

I understand that there are catch-all categories in place, such as "general physics." However, I feel that certain large subfields are just as "worthy" of having a dedicated Q&A category as are astronomy or high-energy theory.

I also understand that, so far, there are relatively few plasma physics questions. However, if this site is serious about being a tool for all branches of physics, then it ought to anticipate and encourage the substantial involvement of currently underrepresented, but large subfields.

Comments

Hi JoshBurby, welcome to PhysicsOverflow and thanks for submitting your paper.

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You could list all questions you see that fall into this category and ask that they are tagged 'plasma physics'. I 'd do the tagging for you. Once you have enough reputation you can add tags yourself.

Answer 1

The partitioning of the Q&A section into categories is very broad by intention. There is only one level of categories, that do not represent single subfields. Instead, to specify the subfield of the question and further narrow down the topic inside the broader category, tags are used in a similar way as they are applied on MathOverflow for example.

On the other hand, the reviews section is meant to be organized by a fully hierarchical system of categories in the long run, using the ArXiv categories at the top level. It is true that at present the tree of categories there is far from complete, and of course the category plasma-physics should appear at the appropriate place. To achieve this, we still need some help from the community. For example here is a thread, where users can suggest a nesting of categories for a specific submission. The categories needed will then be created by an administrator.

Comments

OK, it's good to know that the Q&A categories are meant to be broader than subfields. However, looking at the existing categories and their associated questions, this doesn't seem to be totally true. For instance, isn't astronomy a subfield? Also, the category "theoretical physics," which does sound quite general, seems to be more like a "high energy theory" category. This impression is reinforced by this thread, which implies that, for instance, a theoretical plasma physics question (which, linguistically, is a theoretical physics question) would not be appropriate in the theoretical physics category because theoretical plasma physics is below the "bottom level"
of theoretical physics in the eyes of the site. Likewise, given that the term "phenomenology" is not used in fields like plasma physics or fluid dynamics in the same way as it is used among high-energy physicists, the phenomenology category comes off as also devoted to (perhaps a couple of) subfield(s). So I think a better version of my question would be "how does one add a Q&A category that is appropriate for me?" It seems plasma theory questions only really fit in "general physics," (or "applied physics"??) but it would be nice to be able to categorically separate theoretical plasma questions from experimental ones. More generally, while the site seems to be targeted at a broad audience of physicists, the way the categories are currently set up might betray this intention. 

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@JoshBurby I agree with you regarding Astronomy, it should probably be merged into the other categories.

The only reason why the Theoretical Physics category is dominated by HEP-TH questions is that the current user base of the site is more devoted to HEP related fields. Plasma Physics is totally welcome, tagged with the plasma-physics tag, and Theoretical Plasma Physics does belong in the Theoretical Physics, and is not considered to be at the bottom-level.

The phenomenology section has a broader scope than just HEP - it's simply about finding experimentally verifiable predictions with theoretical models. String cosmology, for instance, would be on-topic in the phenomenology section.

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@JoshBurby I second @Dimension10s comment, and of course experimental plasma-physics questions are welcome in the experimental physics category of Q&A.

That PhysicsOverflow looks a bit dominated by (theoretical) high energy physics at times has previously already been noted here for example. One goal of partitioning the Q&A section into the broad categories as we have them, is to make it explicitely clear that other kinds of graduate-level+ questions are welcome and in the scope of PhysicsOverflow too.

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OK, thanks for clarifying this. I feel more welcome now, and more comfortable encouraging other plasma people to come here :)

Answer 2

Tagging is enough to find special subjects, as posts with each particular tag can be found by clicking on the tags button and then on a particular tag.

It would be helpful though if one could query on the tag page for parts of tags to see which ones are offered, rather than having to go through all tag pages.

Comments

@ArnoldNeumaier I have implemented the requested feature as link on top of the tags page.

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@polarkernel: Thanks!