I just installed the latest Ubuntu 13.10 and I'm trying to figure out what drivers I should install and how to do it. I have an integrated Intel GPU and a Nvidia GeForce GT 650M that should work together according to the Optimus technology. The software updater doesn't show any additional third-party driver available, though, and this makes me think that maybe there are no drivers for Linux 3.11 yet. So the question is: do I have to install additional drivers over the ones preinstalled by the system? If yes, where can I find them?  Thank you and please forgive the mistakes I could have done, but I'm completely new to Linux and I'm trying to get started..
I recently made the switch to Ubuntu. Everything on my laptop works fine except my hybrid graphics card. It is Intel graphics combined with Nvidia GeForce GT650M. I tried Bumblebee, but primusrun doesn't work (segmentation fault, core dumped) and optirun works with glxspheres64, but steam games look worse with optirun than with Intel graphics (e.g. Surgeon Simulator 2013 runs fine with Intel and hangs a lot with optirun)   I tried Nvidia Prime, but it gives me a black screen on startup after install, so I can't do anything and have to power off my PC with the power button. I also tried nvidia-prime 0.5 on Ubuntu 14.04, and then I get 'low-graphics mode' and I can't get to Unity.
Benefits and Drawbacks of Swapping Associations of Positivity and Negativity of the Proton and Electron For historical reasons, I understand that a proton's charge was assigned the label of "positive", the electron's charge was assigned the label of negative, and, crucially, equations of current in E &amp; M are written with the notion that current is the flow of positive charge despite the rarity of actual flows of protons in real systems (which I understand are mostly biological systems).   If the possibility existed to instantaneously and at no cost, retcon these associations such that protons have a negative charge, electrons have a positive charge, and current remains the flow of positive charge, would there be any beneficial or detrimental outcomes?  For instance, would there be:   new interpretations of physical laws that would provide different or better insights into any relevant subfield of Physics significant simplifications to notation in any field of Physics or Engineering significant increases in understanding in the fields of electricity, electronics, electrical engineering, radiation/radiative transport, etc. a noticeably easier learning curve for any subfield of physics dealing with the concept of charge   Additionally, is there a permutation of positive charge, negative charge, and flow of current definition that would improve upon the one I suggested? Jordan normal form and invertible matrix of generalized eigenvectors proof Struggling to find a place to start with this proof- just began learning about Jordan normal.  Given a 2-by-2 matrix $A$ and a Jordan normal form matrix $J_{\lambda}$, there exists a matrix $S = [v1, v2]$ s.t. $$S^{-1}AS = J_{\lambda}$$ That is, $J_{\lambda}$ is similar to $A$.  WTS: $$(A - \lambda I)v_{1} = 0 $$ $$(A - \lambda I)v_{2} = v_{1}$$    I was going to try to start with the similarity condition and work into producing the two statements below.  Transform the similarity condition to: $$(A = SJ_{\lambda}S^{-1}) * v_{1}$$  Rewrite our first statement to prove as: $$Av_{1} = \lambda I v_{1}$$   Substitute: $$\lambda I v_{1} = SJ_{\lambda}S^{-1}v_{1}$$  But I've been continually getting stuck.  Tried a few ways other than this.  What intuition am I missing? How can I reuse existing materials, objects, etc from an existing .blend? How can I set CSS only for specific IE browsers? When using Alt+Tab, I can't seem to get back to Skyrim. When clicking its icon or Alt+Tab to get back, I just see an empty window. Windowed mode doesn't allow me to use it in a Windowed (Fullscreen) manner as seen with other games, so that doesn't seem to be an option either. Is there any way to fix this behavior? How to turn off Wireless power management permanently Lemma vs. Theorem I've been using Spivak's book for a while now and I'd like to know what is the formal difference between a Theorem and a Lemma in mathematics, since he uses the names in his book. I'd like to know a little about the ethymology but mainly about why we choose Lemma for some findings, and Theorem for others (not personally, but mathematically, i.e. why should one classify a finding as lemma and not as theorem). It seems that Lemmas are rather minor findings that serve as a keystone to proving a Theorem, by that is as far as I can go.  NOTE: This  doesn't address my concern, so please avoid citing it as a duplicate. What to write in visa application form and what documents to submit as an unregistered freelancer? There are many visa applicants who are working as an unregistered freelancer (photographer, construction contractor, fashion designer, journalist etc ). Some of these freelancers make really handsome monthly income and don't really need to work as a full time employee. Most of them receive variable amount of payments (cash, cheques, demand drafts etc) When it comes to filling a visa application form (USA, UK, Schengen etc), there is always an employment section in all visa form, eg for Schengen visa employment form :    This is a very important factor to make an application really strong.  Questions:   1 Unregistered freelancers can just simply write their profession? what documents to produce along with the application?  2 Bank statements with variable methods of payments could convince the visa officer that these are all legitimate payments? best practices for organizing digital and physical articles As a thirsty graduate student, I've amassed a burgeoning collection of research articles in both paper and digital formats. Right now I manage pdfs and references with Zotero, but I'm still searching for an organization logic for paper documents that allows rapid access and prevents redundant printing and storage.  have suggested organizing by topic, while another approach is to sort by author name. Topical organization has not worked well for me in the past because my research is highly interdisciplinary, confounding my categorization efforts. For a coupled digital-physical organization system I'm considering the following:   Digital documents and references stored and tagged in Zotero Indicator in Zotero whether or not I've printed in the file Physical documents stored in manila file folders labelled alphabetically   What is the most effective way that you've found to maintain both paper and digital document repositories? I could install with an error message "unknown media /ALL". It could not run WPS Office. Transitivity check vs. Transitive Closure Is checking transitivity of a digraph not easier than (in terms of asymptotic complexity) taking the transitive closure of the digraph? Do we know any lower bound better than $\Omega(n^2)$ to determine if a digraph is transitive or not? Has the concept of non-integer $(n+m)$-dimensional spacetime ever been investigated by theoretical physicists? The following image serves to aid the reader in understanding the "privileged character" of $3+1$-spacetime.    The wikipedia article on , and the  "The priveleged character of $3+1$-dimensional spacetime" in particular, made me think a bit about the possibility that we might live in a non-integer amount of spatial and/or time dimensions.   The notion of attaching a non-negative real number to a metric space has at least mathematically already been described by such concepts as "" and "".   This may sound silly/ignorant/absurd to professional practicing theoretical physicists. To me (a layman), however, it doesn't sound much stranger than the idea of wrapping up six extra dimensions (which is, from what I understand, considered to be a serious possibility by those who study $10$-dimensional String Theory) into intricate shapes called "Calabi-Yau Manifolds".   Has any research on $(a +b)$-dimensional spacetime (where $a,b \in \mathbb{R}_{\geq 0} $) ever been done? If so, what where the findings? If not, why not? I can't use the terminal while gedit command is running Why are downloads destructive in the Star Trek universe? There are numerous places in various Star Trek episodes where references are made to the fact that "downloads" are a destructive operation: you download something from one place, and unless you explicitly made a copy beforehand, what you downloaded is gone from its original storage location and instead appears in some other location. Hence was born the term "copy and download".  There are of course out-of-universe, plot reasons for things happening that way which are exploited from time to time. There is also the out-of-universe explanation of how large media companies feel about people downloading copyrighted works, and a possible out-of-universe explanation that at the time, people in general may not have been intimitely familiar with the implications of the term "download", so they added "copy" to help describe what happens to at least portions of their viewership.  But is there a plausible in-universe explanation for why downloads would be destructive by default, and a specific copying operation would have to be made beforehand so as to not delete the data from its original location?  As for specific examples, these are two that I can think of right now (I'm quite sure there are more):   VOY "Twisted" (S2E06), right near the end, stated by Torres: "Our entire database has been copied and downloaded into somebody else's system." VOY "Message In A Bottle" (S4E14), a little more than five minutes into the episode, the EMH is "downloaded into the transceiver array" for transmission across an alien sensor network to the Prometheus when the latter is in the alpha quadrant, and some 20 minutes into the episode it's established that the EMH is not available in the sickbay and will return later. Mean and variance of Squared Gaussian: $Y=X^2$ where: $X\sim\mathcal{N}(0,\sigma^2)$? What is the mean and variance of Squared Gaussian: $Y=X^2$ where: $X\sim\mathcal{N}(0,\sigma^2)$?  It is interesting to note that Gaussian R.V here is zero-mean and non-central Chi-square Distribution doesn't work.  Thanks. How to get client's IP address using JavaScript? I need to somehow retrieve the client's IP address using JavaScript; no server side code, not even SSI.  However, I'm not against using a free 3rd party script/service. Can you provide a list of objects that needs to be disposed in SharePoint? I have been asked by a client to implement some views for reporting purposes, the views will be accessed via PowerBI, Excel and SSRS. The designated user will only have access to the view and no underlying tables must be available to the user.  The problem I have encountered in that the SQL within the view touches 3 different schemas (All within the same database):   Pupil Provider  Security   The view is:  CREATE VIEW dbo.vTestPermissions AS SELECT a.Column1,        b.Column1,        c.Column1 FROM Pupil.Table1 a JOIN Provider.Table2 b ON a.Column1 = b.Column1 JOIN Security.Table3 c ON a.Column1 = c.Column1   The owners of the Tables/View are as follows:   Pupil.Table1 - Owner Pupil Provider.Table2 - Owner Provider Security.Table3 - Owner Security vTestPermissions - Owner dbo   When I select from the view I get an error:     The SELECT permission was denied on the object 'table3', database   'TEST', schema 'Security'   I have tried giving SELECT permission with and without the GRANT option to the schema, and the tables, but that makes the underlying tables available to the user.  Any help on this will be greatly appreciated. The script works fine if I run it with sh filename, but it ignores all the --exclude parameters if its run by cron:  #!/bin/sh TIMESTAMP=$(date +%u)  WEEK=`date +"%V"` if [ $(($WEEK%2)) -eq 0 ]; then     echo "even";     BACKUP_DIR="/mnt/backup/2_$TIMESTAMP"     mkdir -p "$BACKUP_DIR/www"  else     echo "odd";     BACKUP_DIR="/mnt/backup/1_$TIMESTAMP"     mkdir -p "$BACKUP_DIR/www"   fi  if [ $(date +%u) -gt 6 ]; then     zip -r -y $BACKUP_DIR/www/web.zip /var/www/ --exclude='var/www/\.opcache/*' --exclude='var/www/utils/phpThumb/cache/*' else     zip -r -y $BACKUP_DIR/www/web.zip /var/www/ --exclude='var/www/mycompany/files/*' --exclude='var/www/\.opcache/*' --exclude='var/www/mycompany/szamlazz/xml_szamlak/*' --exclude='var/www/mycompany/files_admin/szamlazz/*' --exclude='var/www/mycompany/files_admin/chatFiles/*' --exclude='var/www/mycompany/utils/phpThumb/cache/*' --exclude='*/backup-guard/*' --exclude='var/www/mycompany/mailer/*' --exclude='var/www/mycompany/attachments/*' fi  exit 0   The above script should create a larger backup on sunday, and a partial on weekdays, but it just zips everything. Should I capitalise "or" between examples? On this site, there are often many different options as an answer, for example both with and without the Oxford comma.  When giving multiple options, should I capitalize the word "or" between them?  Option 1:     Eggs, butter and milk are dairy products   Or   Eggs, butter, and milk are dairy products     Option 2:     Eggs, butter and milk are dairy products   or   Eggs, butter, and milk are dairy products     Notice in Option 1 the "or" is capitalised. In Option 2 the "or" isn't.