It seems clear to me that when I'm in a community with "hard questions" (ie. ones that have clear answer) it makes sense to me that I should accept the best and fastest answer.   However, for a community with more "soft questions" (ie. ones that do not have clear answers) I am wondering if there are some guidelines to follow, or some common practice, for how quickly to accept answers.
I have noticed that some questions get a lot of responses quickly, and the cool fact is that most of the time these initial responses are correct.  I see users are motivated to accept answers. Because many questions take less than 24h to get an acceptable response, I'm unsure what to do when I have a question that takes more than 24h to get a response that I feel is complete enough to warrant being marked as accepted.  And even for acceptable responses, I often hesitate to accept them out of concern that posters will pass my question by if it already has an accepted answer (unless it has lots of upvotes). Does this really deter the higher-quality posters, though?
I do not have much experience in table design. My goal is to create one or more product tables that meet the requirements below:   Support many kinds of products (TV, Phone, PC, ...). Each kind of product has a different set of parameters, like:   Phone will have Color, Size, Weight, OS... PC will have CPU, HDD, RAM...  The set of parameters must be dynamic. You can add or edit any parameter you like.   How can I meet these requirements without a separate table for each kind of product? How to prove $\bar{m}$ is a zero divisor in $\mathbb{Z}_n$ if and only if $m,n$ are not coprime Let us consider the ring $\mathbb{Z}_n$ where $\bar{m}\in\mathbb{Z}_n$  Could anyone help me prove that $\bar{m}$ is a zero divisor in $\mathbb{Z}_n$ if and only if $m,n$ are not coprime  So far I have:  Assume $\exists \bar{a}: \bar{m} \bar{n}=n \mathbb{Z} \Rightarrow$ for some $b\in\mathbb{Z}:am=bn$  I then assumed $n,m$ were coprime and attempted to use $\exists a&#39;,b&#39;\in \mathbb{Z}:a&#39;m+b&#39;n=1$ to come to a contradiction, however haven't found one, the most promising thing I have found so far is that  $a=n(a&#39;b+ab&#39;)$ and $b=m(a&#39;b+ab&#39;)$ $\Rightarrow n|a$ and $m|b$ Gravity as a gauge theory Currently, (classical) gravity (General Relativity) is NOT a gauge theory (at least in the sense of a Yang-Mills theory).   Why should "classical" gravity be some (non-trivial or "special" or extended) gauge theory? Should quantum gravity be a gauge theory?  Remark: There are some contradictory claims in the literature to this issue. To what extent gravity is "a gauge" theory?Obviously, GR is not a YM theory. So, why do some people say that gravity "IS" a gauge theory? I found this question relevant, e.g., then we handle GR in the Einstein-Cartan theory or any other theory beyond GR, like teleparallel theories or higher-derivative gravitational theories. So I think it could be useful to discuss the "gauge flavor" of gravity here. When is an elected moderator shown as "departed" on the election page? On Philosophy, one of the elected moderators has since deleted their account, and they're shown as "Departed" on :        However, , one of the elected moderators still has their "previous" flair shown in place, despite the fact that they've already resigned and left the Network completely in the wake of the recent events.        , the same happens (old flair remains), but without the clickable &lt;a&gt; around the image, and with a noticeable :        This looks inconsistent, so when exactly will a placeholder image showing "Departed" replace the flair for a departed election winner? I'm currently working on a scene containing 1000+ objects which all need to be set to a different draw type to save on computationally expenses in the viewport. But doing this for every object separately is really tedious. Therefor I'm wondering if there's a way to change the maximum draw type of multiple objects simultaneously. Preferably only the selected objects. Why have  on every line How do I prevent widow/orphan lines? Which document class is being used? Is there a way to programmatically determine which document class is in effect?  I'd like to be able to write conditional macros that behave differently depending on which document class is currently being used. Two parties are trying to resolve some dispute that involves interest of both. Sometimes it's hard for them to reach an agreement on a fair basis. This is typically when another party who has no interest involved and no bias towards either party comes into play in order to settle the dispute between the two conflicting parties. The term "third party" seems being used quite often. I would also call it a "middle-standing" party or we could say this party is neutral.  These terms seem NOT formal enough to me though. I'd like to see if anybody can come up with a better one. ... but still be required for applications that need admin privilegies?  In order to allow the following:  $ apache2ctl restart httpd not running, trying to start (13)Permission denied: make_sock: could not bind to address 0.0.0.0:80 no listening sockets available, shutting down Unable to open logs  $ sudo !! sudo apache2ctl restart             #no password asked $                                   #works!   For reference I've seen this setup on amazon's e3 instances  Any idea? In my book about Logic, which is called 'Language, Proof and Logic', by the way, there is explained that the conditional $ P \rightarrow Q $ is equivalent with $\neg P \lor Q$.   that gives as answer: 'just compare the truth tables and you can see that they are equivalent'. However, I would like to know how to prove this using formal propositional logic. This should be possible, right? Suppose that a box contains 10 red balls, 20 green balls, and 30 blue balls.   Suppose also that balls are drawn from the box one at a time at random.  What is the probability that all the red balls are drawn before the blue or green balls are themselves exhausted. What is the probability that as the last red ball is drawn, there remains at least one blue and one green left in the box.  The answer I was given is $\dfrac{7}{12}$ and a general equation is: $$ \dfrac{b g}{1-b}+\dfrac{b g}{1-g} $$ where $$ g=\dfrac{20}{60},b=\dfrac{30}{60} $$ but why? Idempotent linear operators are projections I'm working on this problem: Suppose $V$ is a Hilbert space and $P : V \to V$ is a linear map such that $P^2= P$ and $\Vert Pf \Vert \leq \Vert f \Vert$ for every $f \in V$. Prove that there exists a closed subspace $U$ of $V$ such that $P = P_U$. I did do some searching online and I know that $P$ is an idempotent matrix and I know that $U$ is supposed to be $\text{range}P$, which I can show is closed. However, I'm having a hard time showing $P_{\text{range}P} = P$. I know that I can decompose $f = g + h$, where $g \in \text{range}P$ and $h$ is in the orthogonal complement of $\text{range}P$. I'm not sure how to proceed. Most of the online searches require that $P$ be self-adjoint, but this question doesn't have this condition. Can I get some help? Realtek RTL8723be doesn't have good reception Only when I'm closer to the router, it shows any signal, but when I'm just little far from it, it is not showing wifi routers signals. grep a file, but show several surrounding lines? Drop Tables with Bigger size We have a mysql database with a size of 2 TB, in which we have for to five big tables ranging from 110GB to 350GB. When we try to drop these tables the mysql goes to the defunct mode and hangs in that state for a long time. Is there a solution to drop these tables without mysql hanging. We have a machine which has a memory of 122GB and swap of 60 GB. We use an InnoDB Engine Hope the information suffices kindly help us with this issue I have for quite some time now tried to find a satisfactory answer to this, but I haven't yet. In perturbation theory, with small parameter $\lambda$, we expand the eigenstate as  $$| E \rangle=| E^{(0)} \rangle + \lambda | b \rangle + ...$$  Where $| E^{(0)} \rangle$ is an eigenstate of the unperturbed Hamiltonian. The problem is that when there is degeneracy, there is a choice of these eigenstates. I know the answer is that they are chosen to be eigenvectors of the perturbing Hamiltonian, but my question is why. What's the difference between "cd ../" vs. "cd /.."? How to search for upcoming conferences that will be held in a specific subject Good reading on the Keldysh formalism I'd like some suggestions for good reading materials on the Keldysh formalism in the condensed matter physics community. I'm familiar with the imaginary time, coherent state, and path integral formalisms, but lately, I've been seeing Keldysh more and more in papers. My understanding is that it is superior to the imaginary time formalism at least in that one can evaluate non-equilibrium expectations.