defunct dbus-daemon zombie freezes ssh login for 30 seconds
Long wait time on login
Should flawed questions be closed immediately? Unique quadratic subfield of $\mathbb{Q}(\zeta_p)$ is $\mathbb{Q}(\sqrt{p})$ if $p \equiv 1$ $(4)$, and $\mathbb{Q}(\sqrt{-p})$ if $p \equiv 3$ $(4)$ I want to prove the assertion:      The unique quadratic subfield of $\mathbb{Q}(\zeta_p)$ is $\mathbb{Q}(\sqrt{p})$ when $p \equiv 1 \pmod{4}$, respectively $\mathbb{Q}(\sqrt{-p})$ when $p \equiv 3 \pmod{4}$.   My first attempt is this. In $\mathbb{Z}[\zeta_p]$, $1-\zeta_p$ is prime and $$ p = \epsilon^{-1} (1-\zeta_p)^{p-1} $$ where $\epsilon$ is a unit.  Since $p$ is an odd prime, $(p-1)/2$ is an integer and  $$ \sqrt{\epsilon p } = (1-\zeta_p)^{(p-1)/2} $$ makes sense and belongs to $\mathbb{Z}[\zeta_p]$.    How do I deal with the $\epsilon$ under the square root?  I guess the condition on the congruence class of $p$ comes from that.  Is this even the right way to proceed?  Uniqueness is not clear to me either.  I thought about looking at the valuation $v_p$ on $\mathbb{Q}$, extending it to two possible quadratic extensions beneath $\mathbb{Q}(\zeta_p)$, then seeing how those have to extend to common valuations on $\mathbb{Q}(\zeta_p)$, but I didn't see how to make it work.  I would appreciate some help. Setting ArcGIS Desktop license to lower level for testing whether Python script still runs? I have a Python script that will need to be given to a client.   We are currently evaluating what license level the client will need in order to run the script for their software acquisition purposes.   We all have ArcGIS 10.1 Advanced license in our company.   I checked all the tools and extensions used in the script against the web help and found that they should work on the Standard license level.   Is there a way I can test the script against the Standard license level, when we have no Standard license level in or company (only the higher Advanced level)? How to identify unused CSS definitions from multiple CSS files in a project A bunch of CSS files were pulled in and now I'm trying to clean things up a bit. How can I efficiently identify unused CSS definitions in a whole project? Minecraft Inventory Saving Why do light sources appear as stars sometimes? See for example this photo:    From my experience, the longer the exposure the stronger can this effect be observed. Is this correct? Are there any other factors that influence the creation of these stars (is there a better word for it, by the way?) And what exactly does technically happen? Received an unexpected cashiers check for over $2K from another state - is this some scam? This is actually about my sister-in-law who lives in Georgia. She just received a "cashiers check" for $2395 from a company in Indiana. It looks like this:    She said that she has been doing "mystery shopper" work for a company and thought that this would be payment for that, but that usually the payments she received for that work were just a couple of hundreds of dollars.  She said she had not done that much of that "mystery shopper" work that she would have expected to receive anything close to the amount on this check.  She was asking me about it but I thought that if she does not know the sender, perhaps this could be some kind of new scam and she should check with the local police (which she said she was going to do).  Anyway I wanted to ask here if anyone knows of a scam like this? Considering that the check here seems to be a "cashiers check", how would a scam like this even work?  Update: I just found out that there was indeed a letter included with the check (and it seems to have instructions similar to those mentioned in the answer by "BrenBarn"). This is indeed related to that "mystery shopper" work. Turns out the reason she was not sure was because the sender of that check has a different company name than the company she normally dealt with. Here is a part of the letter: Is there a way to start a PC with Ubuntu from the Keyboard? Because my button &quot;Power&quot; is broken. XSL That Returns the XML unchanged I am looking for a XSL snippet that simply returns the XML unaltered. It sounds trivial but I can't seem to find an example anywhere on the web. Any help out there? String representation of an Enum I have the following enumeration:  public enum AuthenticationMethod {     FORMS = 1,     WINDOWSAUTHENTICATION = 2,     SINGLESIGNON = 3 }   The problem however is that I need the word "FORMS" when I ask for AuthenticationMethod.FORMS and not the id 1.  I have found the following solution for this problem ():  First I need to create a custom attribute called "StringValue":  public class StringValue : System.Attribute {     private readonly string _value;      public StringValue(string value)     {         _value = value;     }      public string Value     {         get { return _value; }     }  }   Then I can add this attribute to my enumerator:  public enum AuthenticationMethod {     [StringValue("FORMS")]     FORMS = 1,     [StringValue("WINDOWS")]     WINDOWSAUTHENTICATION = 2,     [StringValue("SSO")]     SINGLESIGNON = 3 }   And of course I need something to retrieve that StringValue:  public static class StringEnum {     public static string GetStringValue(Enum value)     {         string output = null;         Type type = value.GetType();          //Check first in our cached results...          //Look for our 'StringValueAttribute'           //in the field's custom attributes          FieldInfo fi = type.GetField(value.ToString());         StringValue[] attrs =            fi.GetCustomAttributes(typeof(StringValue),                                    false) as StringValue[];         if (attrs.Length &gt; 0)         {             output = attrs[0].Value;         }          return output;     } }   Good now I've got the tools to get a string value for an enumerator. I can then use it like this:  string valueOfAuthenticationMethod = StringEnum.GetStringValue(AuthenticationMethod.FORMS);   Okay now all of these work like a charm but I find it a whole lot of work. I was wondering if there is a better solution for this.  I also tried something with a dictionary and static properties but that wasn't better either. It just struck me that Utility Companies world-wide supply domestic users at either 50/60Hz. It could have been selected to be 10 Hz, or 100 Hz ... whatever  Was 50/60 chosen at random? Is there some rationale involved (efficiency, easier to construct/control etc) in restricting domestic supply to either 50/60 Hz?  In other words, if I were designing a power system, why would I pick 50/60 Hz instead of some other frequency? How old is Chewbacca? How old is Chewbacca, anyway? Do Wookiees get gray fur when they are old? "She need not worry" or "she needs to not worry"? I just came across this weird use of &quot;need not&quot; on :  Madam/sir, My daughter is stuck in Uk . She has lost her  . She is difficult to return back India home [sic]. Please help  In response,  says:  She need not worry. She should stay where she is. Just tell her to keep herself safe. Please delete your tweet.  Shouldn't it be &quot;she doesn't need to worry&quot; or &quot;she needs to not worry&quot; given that the subject is &quot;she&quot; (singular)? Or is this some kind of grammatical construction I don't know? I believe who wrote it was a native speaker of English and they might be correct. Can someone explain this please? What is special about square numbers here? How to highlight whole row and column under cursor in OpenOffice Calc? I need to work with large table. Something like in this illustation image will be helpfull for better orientation:    Is there some settings which makes this possible? USB flash drive autorun Fixed point of a Function (monotonically increasing) INI file parsing in PowerShell I accidentally changed /var owner/group to my username and then changed it back to root, but not all the /var folders' owners are root, so is there anyway to change back owner/group of files/folders to default state?  Or at least those files/folders that are created by packages? $X$ is a Hausdorff space and $\sim$ is an equivalence relation.  If the quotient map is open, then $X/{\sim}$ is a Hausdorff space if and only if $\sim$ is a closed subset of the product space $X \times X$.  Necessity is obvious, but I don't know how to prove the other side. That is, $\sim$ is a closed subset of the product space $X \times X$ $\Rightarrow$ $X/{\sim}$ is a Hausdorff space. Any advices and comments will be appreciated.