Red shift and expansion of universe
Other explanation for cosmological redshift?
Can I get individual man pages for the bash builtin commands? Is there anywhere you can download a manpage for every builtin commands?  I know you can just use help or man bash and search to find info about it, but I want them separated, so I can just do man read and get the read manpage. How does LIGO remove the effects of environmental noise? Since LIGO is dealing with readings at nanometers, events such as vehicles driving nearby, and constant (but extremely minor) tremors of the earth can cause movement with the mirrors at nanometers.  Such tiny movements are extremely difficult to measure, but can easily cause errors when using such a small scale.  How does LIGO remove these factors, and take precautions to prevent false readings due to noise? In iPhone, you can easily change the default ringtone (Settings → Sounds → Ringtone) and set a custom ringtone for individual people (Contacts → [some person] → Edit → Ringtone).   But can you set a custom tone for a group of contacts? (E.g. "family" or "workmates".)  I think that would be handy—and quite basic functionality, so to speak—but I couldn't find a way to do this through the iPhone UI. Is it possible at all (without jailbreaking)? I have been running Ubuntu 18.04 for a couple of weeks. I upgraded from 16.04 and all went smoothly.   I am not sure what I changed, but this morning I noticed that the "Settings" Icon that launches gnome-control-center is missing from "Show Applications" and the applications menu as well. When I searched from "Show Applications" for gnome-control-center or just settings, nothing showed up.   So, I figured I must have accidentally removed it and figured a reinstall of the package would resolve the issue. I have searched and found several postings where this worked. I tried:  sudo apt install gnome-control-center   And then rebooted - which reinstalled the gnome-control-center and I could then launch it from the command line. However, there was still no Settings Icon in any of the menus.   I also tried many other suggestions including:  sudo apt-get install --reinstall gnome-control-center sudo apt-get install ubuntu-desktop sudo apt install ubuntu-desktop --reinstall sudo apt-get install unity-control-center   However, none of these has been successful in restoring the icon into "Show Applications" or any applications menu.   Anyone have any suggestions on something I haven't tried? Would be much appreciated.  Or, is there a way to just manually recreate the icon?   Output of locate gnome-control-center.desktop:  /usr/share/applications/gnome-control-center.desktop  /home/dccrens/.local/share/applications/gnome-control-center.desktop /home/dccrens/.gnome/apps/gnome-control-center.desktop   I am running Ubuntu 18.04 desktop on kernel 4.15.0-45-generic. How should I punctuate around quotes where the punctuation required by the quote interferes with the punctuation of the sentence? The American convention in quotations is (typically) to place punctuation inside quoted text. But I always run into situations where the punctuation of the quote interferes with the punctuation of the sentence. How would you punctuate this (American, non technical)?     When my friends ask, "What do you want for your birthday?", I never know how to respond.   It seems odd to place the last comma outside the quote simply because of the question mark. Is that the preferred (i.e. most often accepted) standard? How to delete file(s) in secure manner? Is there a way to make sure that a deleted file can not be recovered?   As you know, deleting a file by pressing shift-del or using trash doesn't mean that file is gone forever. It resides somewhere in the computer.  In day to day life, law enforcement or thieves use recovery programs to reveal our private data or something else.   They can recover all data that resides on hard disk, in RAM, and even USB.  To protect us from these people, what should one do? Which program should one use?  Note: I don't want an answer like first use a recovery program then erase that file with shred. With just one program, I want to erase all unused/deleted files on my computer. doGet and doPost in Servlets Bring a window to the front in WPF how many linearly independed vectors combinations may I extract from a set of vectors Consider the set of $n$ vectors $\mathcal{S}=\{v_1,v_2,\dots,v_n\}$, with $v_i \in \mathbb{R}^n$. Let that set generate a subspace $\mathbb{V}$ of $\mathbb{R}^n$ of dimension $r\le n$. How many different unordered basis of  $\mathbb{V}$ may be constructed by picking up $r$ vectors from $\mathcal{S}$. There is a method to find them? What does "may they rot there" mean? What's an atomic superstate/, and how is it possible?  I understand the basics - being something can be moving and staying still at the same time; the observer changes the behaviour - but I'd like to know a little more, as it interests me, and how is it possible without actually interfering with said thing? How can I open a cmd window in a specific location? How can I open a cmd window in a specific location without having to navigate all the way to the directory I want? I have multiple Ubuntu machines at home and a pretty slow internet connection, and sometimes multiple machines need to be updated at once (especially during new Ubuntu releases.)  Is there a way where only one of my machines needs to download the packages, and the other machines can use the first machine to get the debs?  Does it involve setting up my own local mirror?  Or a proxy server?  Or can it be made simpler? "Temporarily unreachable" when using fetch as Googlebot from Webmasters Tools The page I'm trying to fetch is public.  The server logs show no request.  Google reports that any page on my site is "Temporarily unreachable". It won't even fetch the verification file, a static HTML file that was successfully used to verify with the webmaster tool application itself.   My site is running on the .  What is causing this? How to *disable* automatic reboots in Windows 10? Windows 10 lets you 'schedule' a reboot for later. I want to disable it.  Evidently Windows scheduled itself for a reboot last night when I wasn't looking and just closed everything I had been working on the night before.  I reboot on the regular; I don't need Windows to do that for me.  Can I disable it completely? I don't mind if it downloads everything, and then says "hey, you should reboot," but it should never reboot itself, ever.  I'm using the "Pro" edition of Windows 10. One of my advisors suddenly passed away while I was in graduate school.  We had some discussions and ideas about future publications, but he passed away before any of the work was completed.  When the work was finally completed and published, I and my co-authors were therefore presented with an ethical dilemma about how best to acknowledge his contributions to the ideas behind the paper.  Should we list him as a co-author?  Put him in the acknowledgements?  Listing him as an author would give credit for the original idea, however, we would have no way of knowing if he actually approved of—and would want his name attached to—our methods and writing.  In the end my co-authors and I decided to list him as a co-author with a footnote stating that he passed away before publication.  I’m interested to hear from others who have been in similar situations and/or suggestions on what constitutes “co-authorship” when one of one’s collaborators passes away before the publication or work is complete. It seems that I'm missing something about this.  First of all, the series is convergent: $\lim_{n\rightarrow\infty}\frac{2^{-n-1} (n+1)^2}{2^{-n} n^2}=\frac{1}{2}$ (ratio test)  What I tried to do is to find a limit of a partial sum $\lim_{n\rightarrow\infty}S_n$ as follows: $S_n=\frac{\frac{1}{6} n (n+1) (2 n+1)}{\frac{1-\left(\frac{1}{2}\right)^n}{2 \left(1-\frac{1}{2}\right)}}$. Still, the limit is $\infty$ and I'm clearly doing something wrong. I use Ubuntu 12.04 64-bit, I did the following: sudo gedit /etc/apt/apt.conf and added  APT::Install-Recommends "false"; APT::Install-Suggests "false";    But it did not work. When I try to install a package, it still wants to install the suggested and recommended packages. How can I solve this? Do mankind and manmade activities/constructions have any effect on the rotation of the Earth? We walk or ride on our vehicles to our destinations daily. Does our movement have any effect on the rotation of the earth according to Newton's law? What will be the effect if we move all the peoples along with their vehicles at their maximum velocity in one line in one direction along the equator? How much effect will it make? Sorting by "hot" - what does it mean and why are the sort option different between the homepage and the questions tab? It has come to my attention that on the homepage on any given SE you can sort by "active", "hot", "week", and "month".  The tooltip says the latter three sort by "most views, answers, and votes" over different periods of time.  So it seems that this is uses a different formula than the "arbitrary hotness points" that create hot network questions.  What is the formula and what is the rationale for using views here, but not in the network hot questions?    Also, what is the rationale for offering such different sorting options between the homepage and the questions tab?  I have been active for ~4 months and never realized there was a sort by hotness option on a different screen (as I have always looked at the questions tab to see what was new) until today.