Why single way communication in Interstellar?
Why Cooper or Dr. Brand can't send message?
Using ECDSA keys for encryption I know that ECDSA is used for signature only, but I wonder if I can use the public/private Elliptic Curve keys for encryption too.  I have ECDSA SSH public keys and I wonder if I can use them to encrypt data that only the matching machine could decrypt, writing the proper software.  Pointers welcomed. I want to create a circuit that can detect audio frequencies and flash RGB LEDs different colors depending on the detected frequency. The frequency range will be from 20 Hz to 12 kHz, after looking at the chart below.   (source: )    So my question is: what circuit design should I choose to make a good frequency detector? I suppose I would need    Preamp for the microphone (is it necessary for the ADC?) Band pass filters (active or passive?) A microcontroller with an onboard ADC that has a sampling rate of at least 24 kHz.   Before I get too excited, are there any circuits out there that already do this? How can I record my screen on Ubuntu?   The app I'm looking for has ideally all of these features:   Can record in a format that can be played back easily on any platform and/or accepted by YouTube or another popular video site Can record just a window (instead of the whole screen), possibly selecting it with a mouse click Can start recording after a configurable delay (e.g., I launch the app and have time to do arrangements to my desktop/window before actual recording starts) Split Line at Points not splitting at every point in ArcGIS for Desktop? Why does  not split at every point encountered, even if run in an iterative fashion?  Following the suggestions of a thread here and several others, I made a set of points in order to split polylines at specified intervals. In order to do this, I used linear referencing to turn my lines into routes. Then, I exported the attribute table, divided each length by 5, and set points at multiples of 1/5 the length of the line. I used this as the event table to create a layer of events. So, each line has 4 equally spaced points along it, and I thus ultimately need the 5 segments separated by those points.  Curiously, though, when I try to do the second part "Split Line at Point," it seems that only one point is used on a given line at a time, and I'm not sure how it chooses the point (maybe order in its attribute table?) I could run the tool multiple times, but this doesn't seem to solve the problem either. For example, I could see how it would continue splitting segments as more segments are generated, but on e.g. the 4th run I see that some lines are still only split 3 times, even though there is a point within a line segment that was never split and existed before I ran the tool. I'm not sure how the splits are generated, but in any case, it doesn't seem to do what I want it to do, which is produce a split at "each" point.  What should I do to split lines at ALL points along the line? My recollection is very sketchy but this is what I remember....   Film was possibly black and white I saw it as a child in the late '80s early '90s but it's older It was subtitled and in Russian or similar language It involved some astronauts  travelling in space with possibly time travel The astronauts (mostly men) encounter a planet/civilization of only women The women no longer need men to breed and are so become superior and possibly want to eliminate all men    That's all I have to go on, sorry. If HTML, CSS, and Javascript are client-side, why are they components of a PHP file? Infinite coproduct of abelian groups One can see on every text (book, lesson, comments) that a direct sum/coproduct of abelian groups is the same as a finite product but in the infinite case, the direct sum/coproduct is only a subgroup of the product.  Why does an element in an infinite direct sum only have finitely many components different from the neutral elements?  I don't see where the "finite" comes from when I look at the universal property.  Also, in another situation, a condition of "finiteness" appears and I think that is because of the same structure: a freely generated group, vectors space, algebra etc... has elements that are finite product/sum of generating elements. Because, if one really wants an infinite "sum" (or sequence) one may just take a formal serie. That is a ring, hence also an abelian group. Why there's no article with 'Mexican' and 'an' with American in sentence: "She’s Mexican. But she’s married to an American."   (Pimsleur English course) How does one use circular polarizers? Running JAR file on Windows I have a JAR file named helloworld.jar. In order to run it, I'm executing the following command in a command-line window:  java -jar helloworld.jar   This works fine, but how do I execute it with double-click instead? Do I need to install any software? Is there any way I can specify a standard or custom numeric format string to always output the sign, be it +ve or -ve (although what it should do for zero, I'm not sure!) Let $C$ be a finitely generated $R$-algebra where $R$ is unital commutative ring. Let $S$ be a simple $C$-module. Show that the annihilator of $S$ in $R$ is a maximal ideal. What I have tried is: When $C=R$ then it is a direct consequence of the simplicity of $S$ as an $R$-module. Further, since $S$ is simple then $S$ is cyclic (i.e. $S=Cy$ for nonzero $y\in S$). Consider the map $$f: C \to S$$ $$c \mapsto cy$$ Then $\ker(f)$ is the annihilator of $S$ in $C$ and $\ker(f) \cap R$ is the annihilator of $S$ in $R$. I have shown that it is an ideal of $R$ but I have no idea to continue showing the maximality. Is it a true direction or is there anything else I should consider to show the maximality? Why can't I catch Pokemon in Pokemon Go anymore? I'm level 10 on Pokemon Go. I've caught at least 150 Pokemon, and had no problems. Now, every time I try to catch a Pokemon, no matter the level, it just rolls twice in the pokeball, breaks free, then runs away. Can anyone provide some insight on how to fix this problem? Why does my procedure run slowly until I update statistics? A different approach in distributing $8$ distinct balls into $6$ distinct boxes Find the number of ways in distributing $8$ distinct balls into $6$ distinct boxes such that there is at least $1$ ball in each box.  We are well acquainted with the traditional Inclusion-Exclusion principle in solving this and it will come up as $191520$ ways.  I tried in this way:  When we distribute $8$ balls into $6$ boxes we have two possible cases  Case $1.$ There are exactly $2$ boxes with $2$ balls each  Case $2.$ There is exactly $1$ Box with $3$ balls in it.  For Case $1$, the distribution is done by choosing $2$ boxes from $6$ boxes and $2$ balls from $8$ balls and those two balls can be arranged in $2!$ ways. But I require another two balls from remaining $6$ balls to be placed in each of these two boxes which can be done in $\binom{6}{2} \times 2!$ ways. Finally remaining $4$ balls can be distributed in remaining $4$ boxes in $4!$ ways. So total number of ways for Case $1.$ is  $$\binom{6}{2} \times \binom{8}{2} \times 2! \times \binom{6}{2} \times 2! \times 4!=604800$$  For Case $2$, the number of ways is  $$\binom{6}{1} \times \binom{8}{3} \times 5!=40320$$  I am pretty sure the value obtained for Case $2.$ is correct. but I could not find where I went wrong in Case $1.$ How variance is defined? The variance of a random variable $X$ is defined as $E[(x-\mu )^2]$. Why can't it be defined as $E[|x-\mu |]$. i.e., What is the basic idea behind this definition. Thank you. I know that I can append &amp; to a command to run the process in the background.   I'm SSH'ing into an Ubuntu 12.04 box and running a python program with $python program.py &amp; -- but when I go to close the terminal window I get a message saying that closing the terminal will kill the running process.   Why is this? I am using the ampersand to run the process in the background. How can I get it to run regardless of if I am SSH'ed in? How can I customize a system locale? What is Ruby's double-colon `::`? How to set a random value for multiple shape keys? My question is related to my previous asked one:   I have about 300 shapekeys and want to set the random value for all of them . How to do it using scripting?