Can you explain the true identity of Murph's ghost?
How can Cooper communicate with his daughter before the time he went to space?
Since it seems to me, that a lot of people still need sidebar workarounds, I would be interested to learn about the use-cases, experienced challenges and (most important) possible strategies to avoid them by using different approaches. This is related to the methods discussed here:   In my experience there are a few extremely important and constantly repeating patterns, which to my knowledge are still very hard to be solved using more official techniques. I will also contribute my own top-N use-cases, which are mostly related to UX and UI concerns. You are very welcome to add your own scenarios as answers and add comments on how you would avoid a workaround. My dream would be to team-elaborate strong and repeatable solution-patterns for the most common use-cases.  Finally I would be interested in the experiences of all of you who participate in the Aura pilot, which hopefully could make this kind of workarounds obsolete. How to remove app which is greyed out, can't be deleted, won't open and doesn't appear in apps list? I have this app with a greyed out icon which I'm trying to delete.    I tap and hold, and it asks me if I want to delete it and its data. I confirm and nothing happens.  I try to open it and nothing happens.  I go to Settings>General>Usage and it's not in the list.  I reboot the device and it's still here.  Is there another way to force deletion of this (ghost) app? RSA leak bits to factor N How to know where shell variables and functions are set? When I type the set command in my system I've got this extract out :  __colormgr_commandlist='     create-device     create-profile     delete-device     delete-profile     device-add-profile     device-get-default-profile     device-get-profile-for-qualifier     device-inhibit     device-make-profile-default     device-set-kind     device-set-model     device-set-serial     device-set-vendor     find-device     find-device-by-property     find-profile     find-profile-by-filename     get-devices     get-devices-by-kind     get-profiles     get-sensor-reading     get-sensors     get-standard-space     profile-set-filename     profile-set-qualifier     sensor-lock     sensor-set-options     ' __grub_script_check_program=grub-script-check _backup_glob='@(#*#|*@(~|.@(bak|orig|rej|swp|dpkg*|rpm@(orig|new|save))))' _xspecs=([freeamp]="!*.@(mp3|ogg|pls|m3u)" [cdiff]="!*.@(dif?(f)|?(d)patch)?(.@([gx]z|bz2|lzma))" [bibtex]="!*.aux" [rgview]="*.@(o|so|so.!(conf|*/*)|a|[rs]pm|gif|jp?(e)g|mp3|mp?(e)g|avi|asf|ogg|class)" [oowriter]="!*.@(sxw|stw|sxg|sgl|doc?([mx])|dot?([mx])|rtf|txt|htm|html|?(f)odt|ott|odm)" [chromium-browser]="!*.@(?([xX]|[sS])[hH][tT][mM]?([lL]))" [tex]="!*.@(?(la)tex|texi|dtx|ins|ltx|dbj)" [netscape]="!*.@(?([xX]|[sS])[hH][tT][mM]?([lL]))" .../.. _xinetd_services ()  {      local xinetddir=/etc/xinetd.d;     if [[ -d $xinetddir ]]; then         local restore_nullglob=$(shopt -p nullglob);         shopt -s nullglob;         local -a svcs=($( printf '%s\n' $xinetddir/!($_backup_glob) ));         $restore_nullglob;         COMPREPLY+=($( compgen -W '${svcs[@]#$xinetddir/}' -- "$cur" ));     fi } dequote ()  {      eval printf %s "$1" 2&gt; /dev/null } quote ()  {      local quoted=${1//\'/\'\\\'\'};     printf "'%s'" "$quoted" } quote_readline ()  {      local quoted;     _quote_readline_by_ref "$1" ret;     printf %s "$ret" }   I checked all files in my knowledge as /etc/profile, /etc/environment, and/or ~/.bashrc. I didn't find any generation  script or code calling.   Do you have any advice where is come from ? How to check if a column exists in a SQL Server table? Since version 3.2, uTorrent displays ADs in the form of a "Featured Torrent" banner and a small square advertising in the sidebar. Is there a way to disable those? This question was asked in an entrance test for an undergraduate mathematics program today, held all over India.   Question: $f$ is a differentiable function in $[0,1]$ such that $f(f(x))=x$ and $f(0)=1$.  Find the value of $\int_{0}^{1} (x-f(x))^{2016} dx$.  I tried to solve it by substituting $f(f(x))$ in place of $x$, but could not proceed much further. Any hints or solutions will be appreciated. If a sports team is down by 1-2 in a best of 7 series, what is their chance of winning (if both teams have a 1/2 chance of winning every game)? I know that the team has to win 3 of the 4 remaining games. So I thought that from the 4 remaining games, there are a total of $2^4 = 16$ total different outcomes.   Could someone point me towards the right direction to determine the probability of the team winning 3 of the 4 remaining games? Would it be 4C3/16 since the three wins can be chosen amongst the 4 games left? I've been attempting to learn C in my spare time, and other languages (C#, Java, etc.) have the same concept (and often the same operators) ...   What I'm wondering is, at a core level, what does bit-shifting (&lt;&lt;, &gt;&gt;, &gt;&gt;&gt;) do, what problems can it help solve, and what gotchas lurk around the bend? In other words, an absolute beginner's guide to bit shifting in all its goodness. How bug prioritization works in agile projects vs non agile When reporting a defect, we are setting the priority and severity of the defect. How this works with agile development? Is there any specific way ?  How bug prioritization works in agile projects vs non agile.?  Is there any other way of measuring the priority of a bug in agile projects? I downloaded Ubuntu 14.04 (64 bit) lts. I made a bootable usb stick. But I keep receiving this error message upon booting:  SYSLINUX 4.04 EDD 20110518 Copyright (C) 1994-2011 H. Peter Anvin et al Unknown keyword in configuration file: gfxboot.c32: not a COM32R image How can I repair a ceiling fan that hums, but doesn't turn? How to set up USB for Virtualbox? I'm using Ubuntu Maverick and Virtual Box 3+. I have Windows 7 Ultimate. The problem is that it doesn't detect USB drives in Windows 7, but USB peripherals (mouse + keybord) are working.  I followed , but I can't find the user group vboxusers. How can I continue? I would also like to upgrade to the latest version without any risk (without losing my virtual hard disk drive). Recording claimable expenses in GnuCash I am new to accounting and trying to learn a few things as my accounts get more and more complicated.  I currently use GnuCash to record simple income/expenses/assets/liabilities and have had a new situation I don't know how to record.  I am currently billing some expenses for work and for my kayak club to my personal credit card.  Under normal circumstances I would do the following (my +/- may be backwards):  Expense +$100 Credit Card -$100  and then when the credit card bill comes I would pay it off  Credit Card +$100 Chequing Account -$100  For expenses that I get reimbursements for I would like to be able to note that I paid for the expense with my credit card and that I paid off my credit card with my chequing account.  At the same time, I would like to be able to create another parent account (maybe "claimable expenses") that shows that I purchased the item, and was then reimbursed so that an individual expense for work or my club has a zero balance.  I tried to look this up in previous threads but didn't quite understand how to apply this to my situation Any advice would be appreciated. Problems with pie charts There seems to be in increasing discussion about pie charts.   The main arguments against it seem to be:   Area is perceived with less power than length. Pie charts have very low data-point-to-pixel ratio   However, I think they can be somehow useful when portraying proportions. I agree to use a table in most cases but when you are writing a business report and you've just included hundreds of tables why not having a pie chart?  I'm curious about what the community thinks about this topic. Further references are welcome.  I include a couple of links:         In order to conclude this question I decided to build an example of pie-chart vs waffle-chart. I have a LAMP server with following configuration.  CPU : Intel(R) Xeon(R) CPU   RAM : 32 GB  HDD : 80 GB  Running on virtual environment.  All the things in the server are running smoothly. But I have noticed that the RAM usage is the server is increasing each day without any reason.   This is the current memory usage on my server.  # free -g              total       used       free     shared    buffers     cached Mem:            31         13         17          0          0         10 -/+ buffers/cache:          1         29 Swap:            2          0          2   And you can see the last 8 weeks memory usage below.   And i have executed the following command to find how much memory each process is consuming.  # ps -eo size,pid,user,command --sort -size | awk '{ hr=$1/1024 ; printf("%13.2f Mb ",hr) } { for ( x=4 ; x&lt;=NF ; x++ ) { printf("%s ",$x) } print "" }'          0.00 Mb COMMAND        2253.62 Mb /usr/libexec/mysqld --basedir=/usr --datadir=/var/lib/mysql --user=mysql --pid-file=/var/run/mysqld/mysqld.pid --skip-external-locking --socket=/var/lib/mysql/mysql.sock        1171.66 Mb java -jar /etc/vmagent/bin/VMAgent.jar         138.27 Mb /sbin/audispd         127.75 Mb /usr/sbin/named -u named -c /etc/named.conf -u named -t /var/named/run-root          74.29 Mb auditd          73.03 Mb automount          43.14 Mb /usr/bin/spamd --username=popuser --daemonize --nouser-config --helper-home-dir=/var/qmail --max-children 5 --create-prefs --virtual-config-dir=/var/qmail/mailnames/%d/%l/.spamassassin --pidfile=/var/run/spamd/spamd_full.pid --socketpath=/tmp/spamd_full.sock          43.14 Mb spamd child          43.14 Mb spamd child          37.13 Mb /usr/sbin/httpd          37.02 Mb /usr/sbin/httpd          36.52 Mb /usr/sbin/httpd          36.46 Mb /usr/sbin/httpd          36.23 Mb /usr/sbin/httpd ................   For troubleshooting , i have restarted the MySQL and APACHE servers. But the result was same. Restarting the entire server will fix the issue, but i want to know what is the real issue.  Let me know if you have any idea about this issue.  Thanks,  Arun S Something has changed in server 16.04 LTS, I can't find tty1, but I need to make an auto-login on tty1 (in console mode), in 14.04 LTS I can make this work.  I can't find /etc/init/tty1.conf  How to, or a link? Age of universe? Well relativity teaches us that time interval between two events is a frame dependent quantity, then how can we say that our universe is 13.8 billion years old? Should it not depend on who is asking this question? What is the Killing form of $\mathfrak{gl}_{m}$? Consider the Killing form of the Lie algebra $\mathfrak{gl}_{m}$. Then $\{e_{ij}\}$ is a basis for this Lie algebra where $e_{ij}$ is a matrix with 1 in the $i$th row, $j$th column and 0 everywhere else. Then every $A = (a_{ij}) \in \mathfrak{gl}_{m}$ can be written as $A = \sum_{i, j = 1}^{m}a_{ij}e_{ij}$. Since $[e_{ij}, e_{kl}] = \delta_{jk}e_{il}-\delta_{li}e_{kj}$, we have $ad(a)e_{ij} = \sum_{kl}(a_{ki}\delta_{lj} -a_{jl}\delta_{ki})e_{kl}$. From this we have $$ad(a)ad(b)e_{ij} = \sum_{k, r, s}(a_{rk}b_{ki}\delta_{sj} + a_{ks}b_{jk}\delta_{ri} - a_{ri}b_{jk}\delta_{sk} - a_{js}b_{ki}\delta_{rk})e_{rs}.$$ From this how can I see that the Killing form is $2m tr(ab) - 2tr(a)tr(b)$. I know that the Killing form is just the trace of the above centered equation, but I seem to be getting confused with all the indices. I'd like to know how I can recursively (edit: iteratively) compute variance, so that I may calculate the standard deviation of a very large dataset in javascript. The input is a sorted array of positive integers.