I am using Ubuntu 12.04 LTS and have been  using it for a while.   I just rebooted today and got this error:  Kernel Panic: not syncing: VFS Unable to mount root fs on unknown_block(0,0)`   Here is a screen shot the . I used the boot repair disk and tried to fix it but it did not work.  Here is there result of that . I am at a loss as to how to fix this.  Thanks for any help.
Upon trying to upgrade from 10.10 to 11.04 all seemed to go well until the restart. This error message is what comes up:  Kernel Panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)   How do we fix that?
Uninstall kubuntu-desktop I installed kubuntu-desktop using sudo apt-get install kubuntu-desktop but I no longer want to use KDE.  How do I remove all the packages that were installed by this command ?  Thank you There are no book recommendations for Astrophysics here. I will write my own answer, but I am also interested in what are others' views on the question (I will NOT mark my own answer as the best one). Show that $|f(z_1)|=|f(z_2)|≤|z_1|^2=|z_2|^2$. Let $f\in H(B(0,1))$, $f(0)=0$, $f(B(0,1))\subset B(0,1)$. Suppose there are 2 different points $z_1$,$z_2\in B(0,1)$, s.t. $|z_1|=|z_2|$, $f(z_1)=f(z_2)$. Show that $|f(z_1)|=|f(z_2)|≤|z_1|^2=|z_2|^2$.    I have used the Schwarz-Pick Proposition to prove that $|f(z_1)|=|f(z_2)|≤|z_1|=|z_2|$ directly, but that is not enough. Thank you for help! How does the 2009 Star Trek film mesh with Enterprise canon? All of the events in the 2009 Star Trek movie would have taken place after the adventures of Captain Johnathan Archer and company.  So, unless J.J. Abrams and friends decide to completely hand-wave that bit of history as well, all of the events in Enterprise should (in theory) still be able to line up with this new timeline.  Are there any points of conflict in this?  How about any time-travel episodes in the Enterprise series which may have happened differently after the interventions of Nero?  Are there possible good explanations for such conflicts, or are there some which are irreconcilable?  NOTE:  I'm not arguing here whether or not ST2k9 is a part of Star Trek canon.  In fact, this question is specifically granting that it is.  I just want to know if there's any conflicts between the new movie and the existing Star Trek history that remains applicable to it. SUID-bit not working for executables within /tmp directory Printing the value of getuid() and geteuid() from an executable with SUID-bit (chmod +s) turned-on, seems to result with the original caller ID instead of the owner id if the executable is located within the /tmp directory.  When compiling the exact same code to home directory (and executing chmod +s), this seems to work as expected.  I've searched a lot and could not find any reference to such behavior.  Does anybody know why is this happening?  this source is simple as that:  #include &lt;stdio.h&gt; #include &lt;stdlib.h&gt; #include &lt;sys/types.h&gt; #include &lt;unistd.h&gt;  int main(){     printf("%d\n%d\n", getuid(), geteuid());     return 0; } if $x_i$ are IID  continuous random variables, with $E[x_i]=μ$, is the following correct?   $E\left[\prod_{i=1}^n(1+⍺\space x_i)^i\right] = \prod_{i=1}^nE\left[(1+⍺\space x_i)^i\right] =  \prod_{i=1}^n(1+⍺\space E\left[x_i\right])^i = (1+⍺\space μ)^n$  thanks! How do you generate dynamic (parameterized) unit tests in Python? How do you get the logical xor of two variables in Python? This is a follow-up to this question:   Hans Bethe wrote a paper in 1944, "Theory of Diffraction by Small Holes," Phys. Rev. 66, 163. I don't have access to the paper, but from descriptions online it sounds like he proved the following. Suppose a plane wave impinges on an absorbing sheet, and there is a hole in the sheet of diameter $d$, with $d&lt;\lambda$. Let $P_0$ be the power incident on the hole, and $P$ the power diffracted through the hole. Then the transmission is $T=P/P_0=(d/\lambda)^4$.  As a practical application, I think this explains why microwaves don't leak strongly through the metal grille in the front of a microwave oven.  Questions:   Does the thickness of the sheet matter? From references online, it sounds like the hole is treated as a waveguide...? This seems to relate to cutoff frequencies of waveguides, etc.? It seems to me that Huygens' principle would give $T=1$ for $d\ll\lambda$, since in this limit the wavelets are in phase. Why is Huygens' principle invalid here? Is this related to question #1? Is there a simple argument for the proportionality to $(d/\lambda)^4$? Or if not, how does one prove this using the gory details of Bessel functions, etc.? Find coefficient of $x^{50}$ in $(\sum_{i=1}^{\infty}x^n)^3$ Adding a Method to an Existing Object Instance Where are Steam games installed? I want to buy a new notebook in the near future to play games on it. I'm looking forward for the new Steam for Linux client. My question is that where does the Steam install the games, on the home partition, or in the usr folder, or somewhere else? I do not use pre-release (i.e. beta) versions of either Steam or Ubuntu. Is there an editor or IDE (or a script) for substituting the TeX-Commands $ and $$ for opening and closing math regions into the corresponding LaTeX-Commands \(,\) and \[,\]? I'm sure there is a tool - and I'm searching for. I think, this will result in better readable code. A simple search and replace wont do that - but with regular expressions, that should not be problem. I simply do not want to invent the wheel a second time. I want to create a simple figure where images are connected with arrows. Here is what I did:  \begin{tikzpicture} \node[](A) {\includegraphics[width=0.2\textwidth]{a}}; \node[right=1mm of A](B) {\includegraphics[width=0.2\textwidth]{b}}; \draw[-&gt;] (A) to (B); \end{tikzpicture}     But I want the arrow to start and end right at the images with no space between. How can I do that? Space before chapters and contents I am attempting to add a calendar to my Default.aspx in my sharepoint hosted add-in in visual studio. I used the default code-snippet for adding sharepoint lists. Here's what I added to my Default.aspx:    &lt;WebPartPages:WebPartZone runat="server" FrameType="Default" ID="full" Title="loc:full"&gt;     &lt;WebPartPages:XsltListViewWebPart runat="server"         ListUrl="Lists/Calendar"         IsIncluded="True"         JsLink="clientTemplate.js"         NoDefaultStyle="TRUE"         PageType="PAGE_NORMALVIEW"         Default="False"         ViewContentTypeId="0x"&gt;     &lt;/WebPartPages:XsltListViewWebPart&gt; &lt;/WebPartPages:WebPartZone&gt;     and this is the result...    Pretty dang ugly if you ask me. How can I get this looking like a normal share point calendar instead of an unusable mess?  Thank you! How can I set the box plot (i.e. axis) ratio of a usual 2D plot to a given value, say 4:3.  I don't want to use unit vector ratio since the quantities of the independent and dependent variables are of completely different orders of magnitude. How is "Can anyone tell me how can I solve this" wrong? See these sentences:     See there, it seems that someone is inside the house. OVER   See there, it seems that someone is in the house.   Another example:     The doctors found two bullets in his body. OVER   The doctors found two bullets inside his body.   Certainly, both are interchangeable, aren't they? But in the bullet's example, the second one looks natural. I'm not sure why. Is it something that bullets were first out and then they went inside? But if that's the case, someone is in the house is also okay. That person too was out first! Are you less likely to down-vote someone whose gravatar is a photograph of them? I know this is hard to answer since, to the extent that anyone does this, they likely don't do it consciously. In the spirit of Richard Wiseman and  I just wondered what were people's thoughts on it.  Please bear in mind that that's me in the picture, and if you down-vote this, that'll be a real person hurtin', not some abstract symbol.