When I was running Windows 7 on my Lenovo machine there was a pre-installed Lenovo utility which would make it so that anyone trying to see what my webcam sees would instead see a still image of a camera with a cross over it. And thus preventing applications and hackers without root privileges from seeing out of my webcam. I say root privileges because root privileges were required in order to change the settings of the program in order to allow programs to actually use my webcam and get what it sees rather than the still image.  This was a very useful utility for privacy and security reasons, however on Ubuntu I have been unable to find a similar utility which has the ability to do the same. Is there such a utility or is there any way of achieving what I have described?  I am running Ubuntu GNOME 16.04 with GNOME 3.20.
I have an integrated webcam in my laptop. I know that it works and that ubuntu recognized it because at installation it asked if I wanted a photo taken for some kind of image associated with my account. When I look in system settings, I do not see any webcam in the hardware section. I would like to disable the webcam like you can do in Windows, but as I can't find it in my hardware section, how can I disable it? I cannot even unplug it as it is integrated into the monitor. Am I looking in the wrong place?? I am using 12.04
Why does the Hilbert curve fill the whole square? What causes the permittivity and permeability of vacuum? When light travels through a material, it gets "slowed down" (at least its net speed decreases).  The atoms in the material "disturb" the light in some way which causes it to make stops on its path.  This is expressed in the material's permittivity and permeability:  Its ability to transmit electromagnetic waves.  But then what causes the limited permittivity and permeability of vacuum?  There are no atoms there to disturb the light, so what is keeping it from travelling at infinite speed?  Is there a special property of space itself which determines the speed of light?  Or is it the virtual particles in vacuum which interact with the light? $\|h(x)-h(y)\|\geq 3\|x-y\|$ prove that image of open is open How to show $\lim_{n \to \infty} \sqrt[n]{a^n+b^n}=\max \{a,b\}$? Let $a\geq 0$ and $ b\geq 0$. Prove that $\lim_{n \to \infty} \sqrt[n]{a^n+b^n}=\max \{a,b\}$. [Hint: Use the identity $(a^n -b^n)=(a-b)(\sum_{i=0}^{n-1}a^ib^{n-1-i})$]    I need some help! I cannot do it even with the hint... :( When discussing a treaty or international agreement, which is correct?  "There are 100 states party to the treaty." (for example, as used )  Or:  "There are 100 state parties to the treaty." (for example, as used )   Or: "There are 100 states parties to the treaty."  (for example, as used ) I’m struggling with getting \ifmmode to work correctly when used inside an array environment which is inside a displaymath environment.  Here is a minimal example:  \documentclass{article}  \newcommand{\signal}[1]{%   \ifmmode     1#1   \else     2$#1$   \fi }  \begin{document} \begin{displaymath}   \begin{array}{cc}     \signal{a} \signal{b} &amp; \signal{c} \signal{d} \\   \end{array} \end{displaymath} \end{document}   This example generates the following output:        Why doesn’t all invokations of \signal detect math-mode? Issue with 'StringVar' in Python Program Javascript to check whether a checkbox is being checked or unchecked How can I analytically prove that randomly dividing an amount results in an exponential distribution (of e.g. income and wealth)? In this current  the following is being proposed:      Suppose you randomly divide 500 million in income among 10,000   people. There's only one way to give everyone an equal, 50,000 share.   So if you're doling out earnings randomly, equality is extremely   unlikely. But there are countless ways to give a few people a lot of   cash and many people a little or nothing. In fact, given all the ways   you could divvy out income, most of them produce an exponential   distribution of income.   I have done this with the following R code which seems to reaffirm the result:  library(MASS)  w &lt;- 500000000 #wealth p &lt;- 10000 #people  d &lt;- diff(c(0,sort(runif(p-1,max=w)),w)) #wealth-distribution h &lt;- hist(d, col="red", main="Exponential decline", freq = FALSE, breaks = 45, xlim = c(0, quantile(d, 0.99)))  fit &lt;- fitdistr(d,"exponential") curve(dexp(x, rate = fit$estimate), col = "black", type="p", pch=16, add = TRUE)     My question How can I analytically prove that the resulting distribution is indeed exponential?  Addendum Thank you for your answers and comments. I have thought about the problem and came up with the following intuitive reasoning. Basically the following happens (Beware: oversimplification ahead): You kind of go along the amount and toss a (biased) coin. Every time you get e.g. heads you divide the amount. You distribute the resulting partitions. In the discrete case the coin tossing follows a binomial distribution, the partitions are geometrically distributed. The continuous analogues are the poisson distribution and the exponential distribution respectively! (By the same reasoning it also becomes intuitively clear why the geometrical and the exponential distribution have the property of memorylessness - because the coin doesn't have a memory either). How to typeset asymmetrical confidence level limits / uncertainties? Do the laws of physics evolve? How to deal with perfect separation in logistic regression? If you have a variable which perfectly separates zeroes and ones in target variable, R will yield the following "perfect or quasi perfect separation" warning message:  Warning message: glm.fit: fitted probabilities numerically 0 or 1 occurred    We still get the model but the coefficient estimates are inflated.   How do you deal with this in practice? Backup and restore settings in Texstudio Does someone know, how to save all the settings of Texstudio and restore them in a simple way?  Thank you in advance! Is the EmDrive, or "Relativity Drive" possible? In 2006, New Scientist magazine published an article titled 1 [] about the  [] which stirred up a fair degree of controversy and  that New Scientist was engaging in pseudo-science.   Since the original article the inventor claims that a "Technology Transfer contract with a major US aerospace company was successfully completed", and that papers have been published by Professor Yang Juan of The North Western Polytechnical University, Xi'an, China. 2   Furthermore, it was  that the Chinese were going to attempt to build the device.  Assuming that the inventor is operating in good faith and that the device actually works, is there another explanation of the claimed resulting propulsion?  Notes:  1. Direct links to the article may not work as it seems to have been archived. 2. The abstracts provided on the  website claim that they are Chinese language journals which makes them very difficult to chase down and verify. Using headset controls like a smart phone I have a generic pair of smartphone earphones that have the button (along with a microphone) and I would like to use the button as a pause/play key in Ubuntu, like I would on an Android phones music player.  Is there a way to enable this headset control in Ubuntu?  If the headset controls are a hardware feature of audio jacks used in Android phones, the name of that hardware (audio jack) would be appreciated. Why is the Sun approximated as a black body at ~ 5800 K? There is currently no way to delete questions or answers in the iOS app, even with the required Trusted User privilege. We can edit and vote, but not delete.  Can this option please be added to the app? How do I install the Intel Graphics driver in my system? Can someone help me out and explain or point me in the right direction on how to check video drivers and see if my video card running okay?  I had 10.04 installed on my Thinkpad r61 with Compiz Manager and life was great, until the machine took water damage. I bought an ASUS (X54H) since and am trying out 12.04, but the desktop just doesn't look right.  I always struggled with video driver installation. There are no proprietary drivers available in the hardware manager.  When I run lspci | grep VGA:  00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09)   I will greatly appreciate your help. I want to use Linux more, but like I said video drivers appear to be my biggest concern. I have also tried 12.04 on my desktop PC, but again failed to configure video card, so switched back to Windows 7. Seriously, it was fun and all, but I can't and I don't want to stay married to the same woman for the rest of my life - one real life marriage is enough..  Is there a lawyer or process of some kind in the world of Skyrim, and if not, who could help me divorce her?  If all else should fail, (sigh), do I have to take her to the backyard, thwack her head with the shovel and dig a shallow grave? I want to resolve merge conflicts in my Git repository. How to do that ?