Traveling with 2 passports due to 3 month validity but visa on a different passport
I have two passports/nationalities. How do I use them when I travel?
How are unbalanced forces even possible, given Newton's 3rd law? Stack Exchange sites need a universal clock that is visible! Since the Stack Exchange sites run on one clock, and a clock that is not common to most of us (such as those of us in the US), can we display a clock with the site time (UTC) displayed somewhere on every page, such as at the bottom with the other text?  That way we are more aware of when the days turn over, and ecetera...  close votes, delete votes, flags, and normal votes would also benefit from this as well (thanks @Grace Note!)...    What do you guys think? yea or nay? thoughts? How to disable the touchpad? I want my touchpad to be disabled when I use my mouse. How can I do that? touchpad-indicator has stopped working on 11.10. It used to work on 11.04. Gnome3 is not a solution as I don't like it and find it buggy. I'm developing a  application, and I'm using constant NSStrings as ways to store key names for my preferences.  I understand this is a good idea because it allows easy changing of keys if necessary. Plus, it's the whole 'separate your data from your logic' notion.     Anyway, is there a good way to make these constants defined once for the whole application?     I'm sure that there's an easy and intelligent way, but right now my classes just redefine the ones they use. I was wondering, how can I create a timeline exactly like this one:    on LaTeX?  I am a Finance student, and write all of my notes using LaTeX. These timelines, are giving me a headache. Since we use a lot of different timelines because of annuities. I want to learn how to create one basic timeline, so that I can then change anything I want. But basically, I want something like this, with the arrows and everything.  Thank you so much guys! I found  presentation document by D. J. Bernstein. Is it possible to create it in latex?  Screenshot If for two suitable matrices $B$ and $C$, $AA^TB=AA^TC$ can we conclude that $A^TB=A^TC$? Let $A$ be a $m\times n$ real matrix. If for two suitable matrices $B$ and $C$, $$AA^TB=AA^TC$$ can we conclude that $A^TB=A^TC$?  I know $AA^T$ is a symmetric matrix. Every real symmetric matrix is diagonalizable. But I am not sure how to use this information. Thanks for reading and helping me out with hints. Equal standard errors for all levels of a categorical factor in lmer I have a question about the standard error of mixed model parameters estimated using the lmerTest package.  I have 12 sites with 6 treatments over each site. I measured a response variable (biomass_of_insects) (which has a Gaussian distribution).   library (lmerTest)   model &lt;- lmer(biomass_of_insects ~ as.factor(treatments) + (1 | sites))   However, the model summary shows the same standard error for every treatment (see below: 114.065). Why is the standard error always the same?   Fixed effects:                                Estimate    Std.err      df       t        p (Intercept)             501.333     80.656  66.000   6.216 3.91e-08 *** as.factor(treat)F       126.667    114.065  66.000   1.110    0.271  as.factor(treat)I        -8.333    114.065  66.000  -0.073    0.942      as.factor(treat)I+F1/3  -75.000    114.065  66.000  -0.658    0.513    as.factor(treat)I+F2/3   18.333    114.065  66.000   0.161    0.873     as.factor(treat)I+F3/3   15.917    114.065  66.000   0.140    0.889 What should main() return in C and C++? What is the correct (most efficient) way to define the main() function in C and C++ — int main() or void main() — and why? And how about the arguments? If int main() then return 1 or return 0?  There are numerous duplicates of this question, including:       — For C++, with a very good answer indeed.     Related: Product and sum of positive operators is positive I want to show that for $S,T\in B(H)$ bounded operators on Hilbertspace with $S\geq 0,T\geq 0$ and $ST=TS$,  we have $S+T\geq 0$, and $ST\geq 0$.  $T\geq 0$ means $(Tx,x)\geq 0$.    To me it seems that $((S+T)x,x) = (Sx,x)+(Tx,x)\geq 0$. But for $ST$ i like some help.   There is a theorem in Rudin (12.32) that says that for every $T\in B(H)$ we have an equivalence:   $T$ is positive $\Leftrightarrow$ $T$ is self adjoint, i.e. $T=T^*$ and $\sigma(T)\subset [0,\infty)$.   Since $S, T$ are self adjoint we know that $ST=TS = S^*T^* = T^*S^*$ ($ST$ is selfadjoint since $S,T$ commute). Also I read somewhere that if $S,T $ commute then $\sigma(ST)\subset \sigma(S)\sigma(T)$, but I am not sure if this is true. Clearly I cant prove it, but if it were true by this ''Theorem'' it would follow that $ST \geq 0$.   Is there a more straightforward way? How can I define the different properties of an Cycles/Eevee material? Such things as glossy, glass, diffuse, RGB-color, emissive via python scripting? requireJS optional dependency Is the electric force a vector or a vector field? Keyboard shortcut to minimize a window on Ubuntu 18.10 How can I show that $n! \leqslant \left(\frac{n+1}{2}\right)^n$? Show that $$n! \leqslant \left(\frac{n+1}{2}\right)^n \quad \hbox{for all } n \in \mathbb{N}$$  I know that it can be done by induction but I always find line where I do not know what to do next. I am given $f,f' \in L^1(\mathbb{R})$, and f is absolute continuous, I want to show that:  $$\lim_{|x|\rightarrow \infty} f(x)= 0$$  Not sure how to show this, I know that $f(x)=\int_0^x f'(t) \, dt+f(0)$, and I can assume without loss of generality that $f(0)=0$, any help?  Thanks in advance. Right-hand sidebar covers the footer on the "ask question" page and markdown help page Book series about preparation for a war at the Singularity I am looking for a book series (almost certainly a trilogy) that starts with some humans in a space station being abducted by a small funny-looking alien and taken to a prison planet. They find out that the way space travel works is by creating copies of the passengers, and the originals remained on the space station. This is actually good for the aliens since they believe every sentient being will resurrect at the Singularity and will be forced to fight a battle, so the more the merrier.  The one other detail I remember is that the world economy has a rampant inflation, so people take any cash they have at the end of the day and buy 20th-century memorabilia that doesn't devalue as much. Is there a continuous bijection from $[0,1]$ onto $[0,1] \times [0,1]$? That is with $I=[0,1]$ and $S=[0,1] \times [0,1]$, is there a continuous bijection $$ f: I \to S? $$  I know there is a continuous bijection $g:C \to I$ from the Cantor set $C$ to $[0,1]$. The square $S$ is compact so there is a continuous function  $$ h: C \to S. $$ But this leads nowhere. Is there a way to construct such an $f$?  I ask because I have a continuous functional $F:S \to \mathbb R$. For numerical reason, I would like to convert it into the functional $$ G: I \to \mathbb R, \\ G = F \circ f , $$ so that $G$ is continuous. Best way to specify whitespace in a String.Split operation