I'm a new user of Latex and still trying to figure it out. Currently I have a problem where if I want to have a subscript which contains more than one letter, the spacing between the letters is too large. Namely, writing $\hat{\tau}_{eff}$ results in:    What would be the best way to bring "eff" closer together?
Is there something I can add to the preamble of my document such that multiple letters without spacing in a Math environment (such as $NP$) do not have extra spacing between them and are not considered multiple distinct variables? Right now, I have to use $\mathit{NP}$ to prevent any extra spacing, but I feel that it is more natural to add a space between the letters if they are a different variable ($N P$). For example, if I want the multi-letter variable NP, I want to be able to say $NP$ which would automatically be replaced by $\mathit{NP}$. If I want N and P to have the proper inter-variable spacing, I want to do that only when they are separated by a space, like so: $N P$. Is there a way to achieve this? Would it break something that I'm unaware of? Edit: Here's a screenshot that shows what I mean:  So basically, is it possible for line 1 to automatically give me line 3 and for line 2 to give me line 2?
What is the easiest way to export just the selected objects in Illustrator? The title says it all, I want to know what the simplest way to export the selected objects.  In Inkscape, there is a menu option called export selected which does just this.    The aforementioned option lets you export the selection as a composite image or as a batch of individual images.  Both would be nice, but in this scenario I want to export the selected objects as a single image.  I can already create a new document, and paste in the selected items.  I am looking for a way that is easier than this.  How can I save / output / export only the objects I currently have selected, to an image file, in Adobe Illustrator CS5? Rich Snippets not working (and working at the same time?) .NET obfuscation tools/strategy Why Are There So Many Double Initials in Comic Books? Not being a comics expert, I can't be sure, but I think this applies mostly to Marvel comics.  Why do so many characters have double initials?  There's Pepper Potts, Reed Richards, Sue Storm, Peter Parker and I think at some times there was Bruce Banner (when it wasn't David Banner).  Is this an inside joke or is there some reasoning for this? Let $D$ be a , and let $a,b,x \in D \setminus \{0\}$. Then is it true that $\gcd (ax,bx)=x \cdot \gcd (a,b)$ ?    Let $c=\gcd (a,b)$ and $d=\gcd(ax,bx)$, then as $cx|ax$ and $cx|bx$ so $cx|d$. We would be done if we could show $d|cx$, but I am unable to show that. Please help me to solve this problem. Unexpected voltage with switch turned off Counting files in leaves of directory tree In a couple weeks, I will have a long layover in Cairo on a trip from Mumbai to Toronto. I get to Cairo on Sunday at noon and leave for Toronto on Monday at about 1 AM.  I am travelling on EgyptAir business class. While browsing for people who have experiences with a similar itinerary, some people seemed to have said they they were put up ina  hotel by the airline. However, I did not see anything about this when I booked my ticket.   allows me to enter my status (i.e. citizenship etc.) which results in a .  It doesn't appear like I need a transit visa- however it specifies that:     Leaving the airport is permitted for passengers with transit time   between 6 and 12 hours   My transit time 13.5 hours.  Now for my questions:   Is it an issue that my transit time is longer than 12 hours? Can I still leave the airport? What are my options with regards to airport hotels, etc.? Any other recommendations about how I could best utilize my time while in Cairo? Are there published predictions that hydrogen could remain metallic at ambient pressure? Below the question  there is a  that directed me to the BBC News summary . In their attempt to balance the skepticism of this particular reported observation with the potential implications of producing metallic hydrogen in a laboratory, the BBC included some far-reaching possibilities:  If that is true - and it is a controversial claim - it fulfills a more than 80-year quest to produce what many have said would be a wonder material. Theory suggests metallic hydrogen could be used to make zero-resistance electrical wiring and super-powerful rocket fuel, among many applications.  At the end of the article:  &quot;The scepticism here is probably a good thing, in that it will drive many groups towards attempting to reproduce this experiment. This publication will certainly incite the field. Again, if it holds up, this is an exciting result. I think in this case time will tell,&quot; he told BBC News.  ...referring to Marcus Knudson from Sandia National Laboratories.  And Jeffrey McMahon from Washington State University concurred: &quot;With respect to the tiny sample amount: Such experiments are performed in small diamond anvil cells. One challenge would be to make a larger quantity (at once); another, perhaps bigger challenge is to recover even the small sample (ie, remove it from the extreme pressures that it is under in the diamond anvil cell). &quot;Whether the latter is possible is an important open question.&quot;  Question: Are there published, peer-reviewed predictions that hydrogen could remain metallic at ambient pressure? A link or reference would be appreciated. If it's still in pre-print form (AeXiv) that's OK too. If it's possible, a little help understanding the prediction would be great as well: I know there are many predicted crystalline forms of water ice at elevated pressures and/or reduced temperatures, and many or most of these have been observed, but I think most of them revert once pressure is reduced to ambient. Also the  comes to mind. If there is such a prediction of the possibility of hydrogen remaining metallic at ambient, is there an analogous example of this with a material I'm more familliar with, or is this something quite new? Can someone please give me the prerequisites and mathematics required for string theory? Are there some good references to study it, both online and in a book? Please consider I am a newbie in string theory, and only about up to the level explained in Hawking's Brief History of Time and Penrose's Road to Reality. I would prefer something which does not omit rigor, but builds it up.Also, are there good online lectures on this?  (I have covered most of GR, but I am not really comfortable with advanced Quantum mechanics. I have studied QM only from Griffith's book, and a few McGraw hill lecture notes.) What is Skynet's ultimate goal after defeating the resistance? Adding Multiple Maps in QGIS Composer? Divisibility by 7 What is the fastest known way for testing divisibility by 7? Of course I can write the decimal expansion of a number and calculate it modulo 7, but that doesn't give a nice pattern to memorize because 3 is a primitive root. I'm looking for alternative ways that can help you decide when a number is divisible by 7 by hand.  I'm sorry if this is a duplicate question, but I didn't find anything similar on the site. What is the name of the black&white movie about a mirror Earth (universe)? Astronauts in a spaceship have an accident and fall back to the Earth. They are tried in court. It turns out to be a mirror Earth. As I remember (though maybe I'm not totally right) only one professor knows something about that and in the final scene he crashes into a mirror with his wheelchair. In another scene an astronaut realizes that his name can be read from the mirror directly.  Does anybody remember the movie? I have forgotten my ID proof and I'm doing an Indian domestic flight. Can I still fly? I am travelling from Delhi to Indore, a domestic flight. I forgot to take ID proof. Can I still fly? Why has my database connection failed? Recently I have developed software using SQL Server 2012. Now when I try to connect, I get this error message:     Cannot connect to AAFI\SQLEXPRESSA network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 26 – Error Locating Server/Instance Specified) How do I install the Nvidia drivers? I just ordered the Nvidia GTX card. I have a dilemma, though. Should I keep using the driver which is available in "additional drivers" in Ubuntu, or should I install the driver from the Nvidia site?  So which driver is the best for me? Consider the functional equation problem $$ f : \mathbb R \to \mathbb R \text , $$ $$ f \left( a ^ b \right) = f ( a) ^ { f ( b ) } \text , $$ when $ a , b \in \mathbb R $, $ a , b \ge 0 $. So far the only solution I have is the trivial $$ f ( x ) = x \text . $$ Does there exist any other possible solution? Even if the $ f $ doesn't have a closed form in terms of elementary functions, is there some way I could derive a series or an alternative expression for it? I tried to get a little more creative: $$ f ( w ) = f \left( w ^ { \frac 1 w } \right) ^ { f ( w ) } \text , $$ which nests deep into $$ f ( w ) = f \left( w ^ { \frac 1 w } \right) ^ { f \left( w ^ { \frac 1 w } \right) ^ { f \left( w ^ { \frac 1 w } \right) ^ \vdots } } \text , $$ which is equivalent to $$ \ln \big( f ( w ) \big) = \ln \bigg( f \left( w ^ { \frac 1 w } \right) \bigg) f ( w ) \text . $$ I was hoping to generate some sort of series using this. Properties of $\liminf$ and $\limsup$ of sum of sequences: $\limsup s_n + \liminf t_n \leq \limsup (s_n + t_n) \leq \limsup s_n + \limsup t_n$ Let $\{s_n\}$ and $\{t_n\}$ be sequences.  I've noticed this inequality in a few analysis textbooks that I have come across, so I've started to think this can't be a typo:  $\limsup\limits_{n \rightarrow \infty} s_n + \liminf\limits_{n \rightarrow \infty} t_n \leq \limsup\limits_{n \rightarrow \infty} (s_n + t_n) \leq \limsup\limits_{n \rightarrow \infty} s_n + \limsup\limits_{n \rightarrow \infty} t_n$.  I understand the right two-thirds of the equation, and can prove it.  I'm stuck on the far-left third.  I don't understand how that is true. How to make a jquery click event fire only on first click