:  But somehow, despite all of the reasons it shouldn’t work, it does. .   - it is strongly suggested that this doesn't work.  So at best, Shawyer has invented a very inefficient and expensive fan.  Even further - :  Shawyer's &quot;analysis&quot; is a mess, incoherent and deeply confused about fundamental aspects of relativity.  My question is: Has NASA confirmed that Roger Shawyer's EmDrive thruster works? Edit: There may . I just don't know what it means. Edit #2 I don't believe this is a duplicate of the other question - as it is not clear how much to trust NASA's engineers - or what their comment actually means.
Recently, there was some news that said that the researchers at NASA have come across some impossible kind of space engine which does not require any fuel. I have read at a few places like ,  and . They all say that this engine seems to violate the laws of physics including conservation of momentum.  The original paper is .  Is the statement that it violates conservation of momentum true?
Prove or Disprove the Existence of Solutions... How do deactivate plymouth boot screen? Lately, booting Ubuntu on my desktop has become seriously slow. We're talking two minutes. It used to take 10-20 seconds. Because of plymouth, I can't see what's going on. I would like to deactivate it, but not really uninstall it. What's the quickest way to do that? I'm using Precise, but I suspect a solution for 11.10 would work just as well. How do I quickly switch between workspaces in unity? Is this statement true?     You can not travel back in time. If I travel fast enough the clock will start to go backwards, but that does not mean I am traveling back in time. It would only mean that the time reference is producing a negative count. Why can't I say “She died from drinking 18 cans of Coca-Cola”? Instead, the correct sentence would be “She died of drinking 18 cans of Coca-Cola”. Why does that happen? Nothing happens when I press "Submit" on duplicate suggestion For example, in . If you have an $m \times n$ matrix and the rows are linearly independent, are the columns linearly independent too?  I know that it's the case for $n \times n$ matrices. I've yet tried to think about it, and I think the answer is yes, for example the matrix: $\begin{bmatrix} 1 &amp; 2 &amp; 3 \\ a &amp; 2a &amp; 3c \end{bmatrix}$ has linearly dependent rows and columns, but I'm not sure that it works for every $m \times n$ matrix. Is gravity just electromagnetic attraction? Recently, I  was pondering over the thought that is most of the elementary particles have intrinsic magnetism, then can gravity be just a weaker form of electromagnetic attraction? But decided the idea was silly.    But I then googled it and found  article. Is this idea really compatible with other theories as the article mentions? Is there any chance of this proposition being true? Nexus 7 2013 error upgrading to 5.0.2 OTA I updated to 5.0.1 via OTA sometime ago, and it worked fine. Now I got a notification that 5.0.2 is ready but when Android shuts down to install update it returns error (with no other message. My Nexus 7 is rooted but has the stock recovery.  Is there an easy fix that doesn't require factory reset or installing recovery? Why can array constants only be used in initializers? Ubuntu 14.04.5/16.04 and newer on AMD graphics Show that $|z_1 + z_2|^2 < (1+C)|z_1|^2 + \left(1 + \frac{1}{C}\right) |z_2|^2$ Let $z_1$ and $z_2$ be two complex numbers. Show that there exists $C &gt; 0$ with   $$  |z_1 + z_2|^2 &lt; (1+C)|z_1|^2 + \left(1 + \frac{1}{C}\right) |z_2|^2. $$   I tried to simplify the L.H.S and R.H.S, SNF I was finally left to compare between a real number and a complex number  I really couldn't think of anything else. Please help. Avoiding "(Not Responding)" label in windows while processing lots of data in one lump I occasionally need to process a large amount of data from one package off the network, which takes sufficiently long that when the user tries to interact with the application windows adds the "(Not Responding)" string to the window title. I am aware this is because the processing is being done within a call to handle a message (some way up the stack) and therefore is blocking the message pump. I'm also aware the ideal way to deal with this is to process the data asynchronously in a separate thread so the pump can continue running, however this is a LARGE desktop application which is single threaded from top to toe and safely spinning this processing off is not feasible in our time frame.  So with that in mind, is there by any chance a way I can at least avoid the "not responding" moniker (which to most users reads as "has crashed") by telling windows my application is about to be busy before I begin the work? I believe there is something along these lines when responding to a request to close, one can keep asking windows for more time to avoid it proclaiming that your not "closing in a timely fashion"  I should add this is a C++ MFC application. How do I get an XBOX 360 controller working? I have a Microsoft XBOX 360 gamepad with the wireless adapter and I was wondering what I would have to install to use them with Ubuntu I do know that when using this on Windows I have to manually install the drivers for the wireless receiver (if that is relevant.) How much should a "button of Cure Light Wounds" cost (should it be available at all?) Failed to fetch jessie backports repository I'm using a docker image as a base for my own development that adds the jessie backports repository in its Dockerfile and uses that to install a dependency. This image uses the following command to add the repository:  echo "deb http://ftp.debian.org/debian jessie-backports main" &gt;&gt; /etc/apt/sources.list   The problem is that fetching packages from the backports repository now  fails with the following error (this used to work previously):  W: Failed to fetch http://ftp.debian.org/debian/dists/jessie-backports/main/binary-amd64/Packages 404  Not Found  W: Failed to fetch http://deb.debian.org/debian/dists/jessie-updates/main/binary-amd64/Packages  404  Not Found   I looked on that server, and those paths are indeed not present there.  I tried to figure out on the Debian backports site whether this particular repository should still be available, and I didn't find any indication that this was deprecated or something like that.  Is this a temporary issue with the repository, or is the jessie-backports repository not available anymore? And if this is not a temporary issue, what options do I have to use this or an equivalent repository without upgrading to the newer Debian stable version? What does "rc" in .bashrc stand for? Is it "resource configuration", by any chance? What fallacy dismisses problems by presenting "bigger" problems? Wasn't really sure how to phrase this, but I'm thinking of an instance in which someone diminishes a problem by presenting one of larger scope - as a rather shoddy example, "x political problem in America doesn't matter because half the world's population is starving."  I honestly have no idea if this is considered fallacious or not, but for some odd reason I can't shake the feeling that someone has described it to me as a fallacy before. Am I crazy or is there something to this (or something similar)? How to force nginx to resolve DNS (of a dynamic hostname) everytime when doing proxy_pass? I was going through some articles about "African American Vernacular English". . . These articles give some examples, but they do not clearly specify hard rules to be followed in AAVE.  First of all, I don't even have strong skills in Standard English, so understanding AAVE seems a lot more difficult for me. I did, however, craft a few sentences in both SE and AAVE to validate what understanding I do have. Are the following conversions correct? You don't have to validate each and every item, but rather guide me with rules that I should follow, but didn't, in the following examples.   What the hell are you all doing here?  —  What the hell y'all doin' here? Hey you! What the hell are you doing man? Stop that nonsense now. Do you get it?  — Hey you! What the hell ya doin’ man? Stop that nonsense now. D'ya get it? Come on, can't you open your mouths?   — Come on, ya can't open your mouths??  Hey, who's out there?  —  Hey, who out there? I know, you're listening to us   — I know, ya listenin’ to us Somebody is out there man. — Somebody out there man. Wow, it's delicious.  — Wow, it delicious. Holy crap, who're these people? — Holy crap, who these people?