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  FAQ discussion

+ 4 like - 0 dislike

The official FAQ can be found here. This thread is preserved for discussion about specific FAQ's. To propose a new FAQ, please create a new meta post, and tag it with the-faq

Note: This thread is not actively maintained; please refer to the official FAQ.  

This question will serve as the FAQ for PhysicsOverflow (found in the answers). Note that it is not finalised yet, and you should feel free to contribute to it, and share your views on it.     

It includes policies, rules, and FAQs in general.      

asked Feb 23, 2014 in Public Official Posts by dimension10 (1,985 points) [ revision history ]
edited Apr 24, 2014 by dimension10

26 Answers

+ 3 like - 0 dislike
answered Feb 23, 2014 by dimension10 (1,985 points) [ revision history ]
edited Apr 16, 2014 by dimension10
Most voted comments show all comments

Maybe we should separate the history PhysicsOverflow from the FAQ, as they do on MathOverflow. And I have slightly mixed feelings about talking about Physics SE issues too much here. Maybe we should apart from importing some questions, rather mind our business here. On MathOverflow for example Quid gave me the advice to not talk about the negative history of Physics SE when announcing the site there, so maybe we should rather look forward to the future than backward here too?

I know and often feel the same... ;-), they are currently raising my blood pressure once again...

I second Dilaton on the history and on SE, you can completely ignore SE, they are not a useful site, they have become pure low-level BS. Consider not what is on your mind, but what a person reading the FAQ absolutely needs to know--- they need to know "what is an appropriate question?" "What do I do about a bothersome user following me around saying nasty remarks?" "How do I insert an image into my submission?", not "What does Dimension 10 think about Stackexchange?". Perhaps the FAQ can wait until there are actual frequently asked questions? Right now, nobody has any questions.

I also think it is a good idea to copy the "Be nice, be respectful" policy from other sites, and to encourage users to report problem users to Dilaton or to Dimension 10, and ask them to be blocked. This is good, because it allows you to see which users are playing political games. If someone asks you to block someone, just block this user for 30 days. They'll get the idea.

For rudeness policy, you don't need to punitively enforce the policy at all, except by saying "Keep it civil!" Whenever there is something bad. That's usually enough. If there is a comment "Bozo, you suck!", it can be deleted on the grounds that it contains no original physics, and is therefore useless, same as a comment that says "Nice job! I love you!"

@RonMaimon I don't think any rudeness policy is needed, in the first place. I agree that such things also need to be included in the FAQ, it is still under construction.      

Suggested bill of rights:

1. privacy and anonymity: Anonymity will never be breached without a public comment by the author specifically requesting it, (see here: http://www.physicsoverflow.org/13966/protecting-anonymity ). Anonymizing proxies are allowed to answer, but not to register new users and vote. Any IP address information will only be used to prevent sock-puppeting or other clear community accepted abuses, and that any investigation in response to sock-puppeting will respect the anonymity of innocent users to the maximum extent practicable (for example, sorting out who is who by a non-academic person, without snooping on the address of anonymous contributions), naturally we will never sell any private information from the site, nor will we allow third parties to monitor the site traffic.

2. Protection of text: the final say on the text always belongs with the original author, and there is no imposition of content change without reversion. Any hiding/deletion of text will be for a publically stated reason, which is "off topic, spam, duplicate, plagiarism, low-level material, incomprehensible text which could not be explained by author". But it is requested that the author try to make efforts to help clarify the text in case others have a difficult time understanding it.

3. No secret trials: All deliberations regarding blocks and punitive restrictions will be public to the meta community, and point to clear violations of obviously necessary policy (spamming, obvious gibberish, clearly off-topic posting), a list which will never expand to include rudeness or popularity contests. A user may never be blocked for unpopularity or incivility, only for violations of clear content rules, and then only if they cannot be dealt with any other way. Blocked users will be allowed to challenge their blocks. Consensus required for blocking will need to be nearly unanimous, and the main goal is to avoid censoring topics politically, as has happened sometimes in the past in academic journals and on arxiv.

4. No exploitation: any revenue for the site will be mindful of the community, and will not abuse sensitive information. So no private or public entity is going to get consent to sniff the data stream here, perhaps we should delete anonymous IPs so that we cannot supply the information even under legal order.

5. technocratic moderators: comprehending administration. Moderators are expected to understand the technical content of disputes. This does not mean that they are allowed to impose their understanding through censorship, rather they use this understanding to judge if something is off topic, or low level. Right and wrong are for the community to decide, based on comments, and fair voting. Moderators will be selected based on technical contributions to the site, high-quality original material is most significant, and not on the basis of independend political popularity contests, which are easy to fix online. When there are sufficiently many moderators, they should rotate in and out randomly, like jury selection, so that nobody will be able to accumulate political power.


Most recent comments show all comments
As I understand it, the author having the final say does not prevent edits that improve the readability such as for example make LaTex compile or improve the classification such as retags and recategorizations in the Q&A section in particular, but the OP has always the right to revert an edit? I think posts where the OP is so confused that heavy edits and clarifications are needed, are not a good fit for here anyway as people here can expected to be able to express themself clearly ...

Those edits couldn't possibly be controversial, unless someone accidentally reformats an equation to say something subtly different from what was intended (I had this happen to me a couple of times), and it doesn't stop people from editing, just saying that the ultimate judge of meaning is OP. The way to deal with stuff that can't be edited to be appropriate is to close it, but I suspect that the content disputes will be of the kind that happen on Wikipedia, where people with a novel sounding idea will be edited to say something less radical than they intend, and then you need to have the freedom to keep your wording exactly as radical as you intend.

+ 2 like - 0 dislike

(1) What is Physics Overflow?  

Physics Overflow is a question & answer site for physics (including theoreticalexperimental, and phenomenology)  at the graduate-level and above. Beyond this, there is also a reviews section where papers from ArXiV are automatically imported to Physics Overflow by a bot, and papers from other databases can be manually be added (probably by a plugin) for reviewing. Other users may add comments on the paper, or review the paper. The questions and answers are votable, as they are on the main site.      

There is also a meta where you can discuss the site itself, including bugs, feature requests, support requests, community moderation, and discussion in general.      

There will also be a chat room, soon. The chat room is intended for issues that need a quick reply.   

answered Feb 26, 2014 by Dilaton (6,240 points) [ revision history ]
edited Apr 15, 2014 by Arnold Neumaier

Change "high-level (graduate-level and above)" to just "research- and graduate-level". Then "where you may ask" doesn't make much sense with how we plan to implement that section.

@RyanThorngren Fixed.   

Hi @ArnoldNeumaier ... :-))) ?

Thanks for help editing the FAQ! Concerning the links to the pages on PhysicsOverflow, we have made them relative, because when going public beta, the site has to be moved to its final home www.physicsoverflow.org from this temporary place ...

Cheers !

@ArnoldNeumaimer Welcome to Physics Overflow! Thanks for the grammar fixes.

The links are relative at the moment until we move to our permanent URL. So I have made it relative again, but thanks anyways for the other fixes!   

+ 2 like - 0 dislike

(2) The question and answer (Q&A) section

This part of PhysicsOverflow is meant to be some kind of a revival of Theoretical Physics SE with a slightly lowered (graduate-level upward) bar to ask and quite a broadend scope. Basically, all graduate-level upward Physics is on-topic here. 

On-topic topics in this section include:  

  • Theoretical Physics 
  • Experimental Physics 
  • Phenomenology
  • Astronomy, Astrophysics, Cosmology
  • Mathematical Physics and Mathematics extremely relevant to physicists, or that needs to be answered from a physics perspective 
  • Resource recommendations and Specific Reference Requests
  • Software Recommendations        
  • History of Physics
  • General Physics 

Examples of off-topic topics include:  

  • Engineering
  • Basic Physics
  • Simple mathematics not needing a physicist's point of view, or not being relevant to physicists much    
  • Non-conceptual physics (simply a copy-paste of a homework problem, for example)      
  • Why is bamboo poisonous to humans but not to pandas?   
answered Feb 26, 2014 by Dilaton (6,240 points) [ revision history ]
edited Mar 30, 2014 by dimension10
Most voted comments show all comments

"Engineering physics" I think should be allowed as on-topic, the same way that mathematical physics is allowed on mathoverflow. Engineering questions are often physics too, for example, "how do you make an x-ray focus aperature?" Or "what is the dependence of the buckling force on the number of struts in this particular support structure?", you often get a new fundamental insight from thinking about specific engineering issues, scaling laws, and so on. The off-topic thing should be optimization engineering, like "what is the most cost-effective strut structure resistant to bucking for this load?". I think it is extremely difficult to draw the line where physics ends and engineering begins, as fluid dynamics is an example of a system where the fundamental physics is well understood, but understanding the turbulence cascade is pure physics, although the literature is mostly in engineering journals.

@Ron Maimon On the poll on the blog, 10 people (the highest) voted for making engineering off-topic, whereas 4 people (the lowest) voted for making Applied Physics off-topic, and therefore, Applied Physics is on-topic while Engineering is not at the moment.

Maybe I somewhat agree with you, though. I think you should bring that up in a new question if you have time,...  

@RonMaimon Overruling a community decision just doesn't sound right. Probably because that is what the moderators did and still do on SE. It is hard to decide if a moderator is "abusing" or "constructively using" their powers.   

But then again, the poll had no downvoting option, so that's a source of error. Maybe users were just more enthusiastic regarding whether engineering should be banned or not : ) I think the best idea is that when we go online, there should be a proper discussion regarding the issue, and then exercise the consensus. 

Dimension 10: The "community" consists of about 10 people, each one with a different opion, and eventually, because of certain biases of who comes to talk to you, you might get the sense that nearly all of them would like that such and so would be banned from the site, or that such and so topic should be censored, and the arguments always seem superficially reasonable.

The "community" is not really making decisions, there is no consistent community, unless it emerges from a cooperative group which makes an effort to produce a unified consensus. There is always a bias of attention caused by who has time to lobby the authorities, and as an authority, you need to make a consistent picture for what you are willing to accept and what you are not, independent of the voting, with underlying principles, and go by this.

But since it seems you just did, by your criterion of "don't overrule the vote we held before", I get your position, and maybe it is incorrect to overrule in this case, but the general principle on these sites is that you can't trust democracy, because of the issue of attention bias, and it becomes dominated by terrible people.

At Wikipedia, what happened is that there were a bunch of people who came with the sole goal of gaining power, made no edits of a constructive nature, they didn't write anything, they only deleted stuff, and then they made this into a virtue amongst each other, and voted themselves into positions of power. There are always those people, so you have to make sure to avoid it. I think the right way to do it is using the scientific meritocracy set up by reputation, to make decisions among a community of mutual trust, among those that make large contributions. This is how Linux works, with Linus Torvalds at the top of the heirarchy, and then other kernel folks, roughly in proportion to their code base. They are extremely efficient in their decisions.

The model here is that the reputation should work this way, but even so, people should be protected from censorship by even physicists of very high reputation, it is important to make sure that people don't get censored, this is the recurring issue on these things.

Most recent comments show all comments

Yes, and I think conversely to Physics SE, our agreed upon "policies" (I started to dislike this term in that context...) should generally be rather soft guidelines our free and accademic in spirit community naturally follows by itself, without being told or even enforced to do so. The moderators (and empowered users) for example should help and support the PhysicsOverflow community and not suppress it as it is done on P.SE ...

@RonMaimon No, I am not saying "don't overrule the vote we had before". I do realise that the vote was done with little discussion, just a poll, without even a downvoting option. I think we should have a re-discussionn, probably now, but it should continue to the point when we have a public beta, as to whether engineering should really be off-topic. 

I agree with you on what happened on Wikipedia, but it was easier on Wikipedia than it would be here, because Wikipedia actually had policies encouraging the deletion of technical content, which were just not exercised at the beginning. Our aims are totally different, and people like we-all-know-whom-on-wikipedia don't have any sensible logic that can pertain to our aims, and the consensus can never be in their favour. 

Deleting too much technical content and adding nothing of value would get them blocked. I think we should have a public "block log" thread in which such trolls should get publicly defamed, by listing down all their actions. 

And no, don't worry, trolls cannot try to get content censored or real contributors banned, as that goes against the fundamental guidelines of the site.   

+ 2 like - 0 dislike

(3) The review section (a feature to come soon)

This section of PhysicsOverflow is dedicated to reviewing and discussing research papers in "real-time" .

How to import papers

As discussed here, all ArXiv physics papers (older and newly incoming ones) will be automatically and silently imported by a bot.  In addition, each user can manually import papers he would like to review and discuss from other places and data bases, by means of a plugin.

How to look for interesting papers in the Reviews section

The Reviews section will be structured by the well known ArXiv physics categories supplemented by a hierarchical tag system. This allows to efficiently search for interesting papers by tags.

Judging accuracy and originality of a paper

For the Reviews section, there will be a new type of question, which will allow the reviewers to judge the accuracy and originality separately by two separate votes. From the corresponding  two scores, one for accuracy and one for originality, a final score will be calculated to judge the paper as a whole.

This review system works best, if people vote only when they feel they have an insight regarding the topic, and understand the material well enough to make a decision regarding the subject matter. Optimally, up and downvotes concerning the accuracy and originality of the papers are accompanied by detailled explanatory (supporting or critical) answers and comments respectively, such that the present judgement of the paper by the PhysicsOverflow community is transparent and motivated by physics arguments. Also, it is encouraged to change votes later, as needed.

answered Feb 26, 2014 by Dilaton (6,240 points) [ revision history ]
edited Mar 30, 2014 by dimension10

This part of the FAQ should be corrected and further expanded as needed, at best by @RonMaimon ;-), as he has the most detailled conception about how the Review business should work here ...

I came here to write this, but I think you did a good job. The most important thing is to ask people, on their honor, to really make an attempt to not vote politically, but really based upon a detailed evaluation of the physics, to avoid negatively reviewing something that is difficult but correct, or positively reviewing something seductive and incorrect. This is not something you enforce by rules, but by asking people to vote only when they feel they have an insight regarding the topic, and understand the material well enough to make a decision regarding the subject matter. This decision could change as new comments/answers are added, so please, encourage people to feel free to change their vote, and to try their best t stay honest.

Regarding the refereeing, the stuff you said is all I can think of to say.

Thanks Ron for this addition, I have copied some of it into the description of the Reviews section...

@Polarkernel I have just read, that the ArXiv has 16 servers distributed all over the wold to speed up the accessibility. So I am now wondering a bit if it is really wise to physically upload the papers on our single server, instead of just producing links to the paper that point to the nearest ArXiv server? What are the advantages and drawbacks of physically importing vs just linking from a "global international" point of view?

@Dilaton I don't understand your comment. Actually uploading the papers here is a terrible idea, and would probably run over the 15 GB space limit nearly instantly.

So does "importing" the paper just mean creating a submission question for it ...? I would not see the point in uploading the papers either ...

+ 2 like - 0 dislike

(4) What software does Physics Overflow use?

We use Question2Answer v1.6.2 with the following standard Q2A-provided plug-ins:    

  • Basic AdSense (not enabled yet
  • FaceBook Login (will never be enabled)   
  • Event Logger   
  • reCaptcha 
  • Tag Cloud Widget 
  • XML Sitemap 

The following external plug-ins: 

And the following plug-ins by polarkernel:  

  • Physics Overflow Attributions 
  • Physics Overflow MaThJaX 
  • Merge User Accounts 
  • Regain TP account page (disabled
  • Reset account 
  • Search for User 
  • Import SE thread  
  • Physics Overflow Buttons Plugin  
  • Correct User   
  • Rename User 
  • Adjust Imported Votes
  • Reverse Serial Voting  
  • Ping Detector  

The theme that we use the PhysicsOversnow (officially PO-theme) by polarkernel which is based on the Snow theme by Q2A market.   

Below are some differences from the SE software:  

  Stack Exchange Physics Overflow (Q2A)
Comment Voting Only positive Positive and Negative
Vote Counts   Net score displayed[1] Vote counts displayed 
Downvote rep change A fifth or two of upvotes Same as upvotes
Accepting answers Yes[2] Disabled
Approve suggested edit 2 users needed 1 user enough
Bookmarking "Favouriting"[3] Bookmarking[4]  
Autodeletion Inactive questions auto-deleted Questions never auto-deleted 
Comment length $\leq$ 600 characters Almost unlimited
Ping Detection Only if they have been involved in a thread, and some confusing restrictions Pings all user mentions

[1]: Users with at least 1k rep, or who have installed a userscript, may click on net score to see vote counts  

[2]: The idea of accepting answers was completely unnecessary as the decision gives the false impression that the accepted answer is really the best. 

[3]: And prominently displayed near the "upvote"/"downvote" buttons, making it a misleading cue for  question rating.   

[4]: Can be used for any purpose wanted, but should not be mixed up and made a cue for question rating  

answered Feb 26, 2014 by Dilaton (6,240 points) [ revision history ]
edited Apr 12, 2014 by dimension10
+ 2 like - 0 dislike

(6) How is Physics Overflow different from other physics sites? 

As of today, 25/10/23/2/2014, Physics Overflow is clearly different from any other Physics Q&A site. 

Physics Stack Exchange

Physics Stack Exchange is a site for general physics, including popular physics, low-level physics, etc. The policies and politics of Physics Stack Exchange is also drastically different. E.g. Physics Stack Exchange encourages niceness, while Physics Overflow was born with the intention of encoruaging frankness, and not having to be "polite-ically correct".              


Quora is more for popular-level questions, as opposed to technical questions. It is also very broad-scope.                              


MathsOverflow is primarily a research-level mathematics site, even though mathematical physics is allowed. 


TheoreticalPhysics.SE was a site only for research-level theoretical physics. PhysicsOverflow's Q&A section is some sort of a revival of TheoreticalPhysics.SE, but with a much broader scope. We accept not only Theoretical Physics, but also Experimental Physics, Astronomy, and Phenomenology. Our scope is also more broad, since our scope is not exclusively research-level, but graduate-level and above. 

All the questions from Theoretical Physics Stack Exchange have been imported into PhysicsOverflow, and all the graduate-level ones on Physics Stack Exchange will soon be.  


PhysicsOverflow.com was a SE-1.0 site which was later taken over by Physics Stack Exchange. It was mostly populated with sub-graduate-level questions. It is not affilated in any way with PhysicsOverflow.   

answered Feb 26, 2014 by Dilaton (6,240 points) [ revision history ]
edited Apr 16, 2014 by dimension10

You shouldn't have "TheoreticalPhysics.SE" here, because it no longer exists!

@Ron Maimon Changed to "was". Thanks.  

It should be mentioned here that the former TP.SE is fully integrated into PO (once this is true).

@ArnoldNeumaier Done.   

+ 2 like - 0 dislike

(7) How do I post a question, answer or comment on Physics Overflow? 


  1. Click on the "Ask Question" button in the navigation bar: image
  2. Enter the question title, category, and tags. Type your question using the tools provided.
  3. Explanations for each button  
    • makes the text bold. 
    • I makes the text italix.  
    • S makes the text striked through.                 
    • x2 makes the text subscripted.  
    • x2 makes the text superscripted.  
    •  starts an ordered (numbered) list. 
    •  starts an unordered (bullet) list.  
    •  starts a blockquote.   
    • \(\TeX\) opens a pop-up window, which allows one to input \(\LaTeX\) code. 
    •  opens a pop-up window, which allows one to insert an image.  
    •  opens a pop-up window, which allows one to insert a table.       
    •  inserts a horizontal rule.      greek letters) 
    •  (1) opens a pop-up window, which allows one to add or edit a link. (2) removes the link on a particular text.      
    •  adds an anchor in the text.        
    •  makes the editor full-screen. 
    •  opens the source editor, which allows you to input HTML code instead of a WYSIWYG editor. Re-clicking this will take you back to the WYSIWYG editor.   
    • "Styles", "Format", "Font" and "Size" allow you to format the text, and they need no further explanation.    


Go the answer form below the question:  

Then type your answer in the exact same way that you would type a question.       


Click the "comment" button beneath a post:  


Enter your comment the same way you would enter a question or an answer, and then, post it.     

answered Feb 26, 2014 by dimension10 (1,985 points) [ revision history ]
edited Apr 7, 2014 by dimension10

Whoa! Good job. After seeing the features of the little buttons, I guess I am not as against them as I was before. I still wish they didn't take up so much space, tho.

@Ron Maimon I think a few buttons are unnecessary, see here. And there is just' too much repetition in the options for "Styles", and some are unnecessary, etc. 

For example, the symbols button is completely useless, they don't even contain, e.g. greek letters, and one can use $\LaTeX$ for most of those symbols, or even plain text, anyway. 

+ 2 like - 0 dislike

(8) How do I edit a post? 

Indeed, posts on Physics Overflow are editable. If you have more than 500 reputation points, you can edit a post (questions, comments, answers, everything!) directly, by clicking the "edit" button below the post. 


If you have less than 500 reputation points, then you can click the suggest edits button which has the same icon as the edit button. 

You can then follow the instructions given on the site there (expand the instructions) to suggest a new edit to the post. Someone with editing priviledges will review the edit and perform it for you.  

answered Mar 6, 2014 by dimension10 (1,985 points) [ no revision ]
+ 2 like - 0 dislike

(9) How do I close/reopen/delete/undelete a post? 

Users with less than 500 reputation cannot do any of those. However, they can still help out by downvoting and flagging bad posts.  

The following instructions apply to users with at least 500 reputation.


If you spot a bad or off-topic question, then help us moderate the site by voting to close it. Below the question, you will find a button that says "vote to close" 


Click it. You will be lead to a page on which you can propose the question to be closed. If the suggestion to close the question already exists, you can just upvote the existing suggestion. 

When the suggestion (whether it is yours, or someone elses), reaches a net score of +2, the question will be closed by a moderator. 


The same holds for reopening. If you feel that a question has been wrongly closed, then you may click the "vote to reopen" button under it, which will lead you to a page, where you may propose that the question be reopened.   

If the suggestion (yours or existing) reaches a net score of +2, the question will be reopened by a mod.     


Go here. Then do the same.  


Go here. Then do the same.              

answered Mar 6, 2014 by dimension10 (1,985 points) [ revision history ]
edited Mar 23, 2014 by dimension10
+ 2 like - 0 dislike

(20) How do I cite Physics Overflow?  

User contributions on PhysicsOverflow are all licensed under CC-BY-SA-3.0 as stated at the bottom of every page.  

If using user-generated content from PhysicsOverflow, please be sure to clearly state that the content is from PhysicsOverflow, link to the post, clearly state the username of the poster of the content, link to the user's user page, mention the time at which the post's content was taken (correct to the nearest minute, and with time zone specified), and a link to PhysicsOverflow. For example, 

This post imported from PhysicsOverflow at 2014-03-30 15:47 (UCT), posted by SE-user physicsnewbie

In a research paper, report, etc., the following citation style is acceptable,   (\(\mathrm{Bib}\TeX \))

@MISC {4657,
    TITLE = {FAQ for Physics Overflow},
    AUTHOR = {dimension10 (http://www.physicsoverflow.org/user/dimension10 )},
    HOWPUBLISHED = {PhysicsOverflow},
    NOTE = {URL:http://www.physicsoverflow.org/4657 (version: 2014-03-21)},
    EPRINT = {http://www.physicsoverflow.org/4657},
    URL = {http://www.physicsoverflow.org/4657}

For answers, use the title of the question.  

To find the permalink to a post (question/answer/comment), click on the "asked"/"answered"/"commented" button. You may end up with a URL like this one:  


It is enough to use the shortened form of the URL:  


I.e. remove the question title and the ?show parameter with it's value from the URL if you want a short URL.  

answered Apr 8, 2014 by dimension10 (1,985 points) [ revision history ]
edited Apr 19, 2014 by dimension10

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