Heisenberg's principle in classical world
If an object is large enough and slow enough is there a point that we can say we know its position and momentum?
Questions with no close votes appearing in the close vote queue? I've just been offered the wonderful opportunity to review .        ... but on closer inspection ?        Is this  (e.g I'm assuming this post did previous have a close vote, but has now aged away in ways I don't understand), or should questions with no active close votes be removed from the queue.  p.s. If it's , please expect my  asking for this not to be the case ;). I just posted on a closed question   How?  Side point:  I do not see any indication that the post is closed on the app I accidently ran  sudo chmod 755 -R /   instead of  sudo chmod 755 -R ./   I stopped it after few seconds, but now there is some problems such as  sudo: must be setuid root   How can I revert permissions back? Irfanview nearest equivalent for linux "Coming soon" pages & SEO I am setting up my personal website, and I have designed a simple "Coming Soon / Under Construction" page which basically has nothing but a small notice for the users.   What kind of SEO can I make on this page such that it won't harm the full website's ranking later on? Exclamation(!) turned in to question mark(?) in title field I just submitted a question () with an exclamation (!) at the end of the title (with one space between the word and the exclamation) but it turned in to question mark (?).   I removed the space between the word and the exclamation, then it shows normal.   Is this an intended feature? Sometimes we assume that regressors are fixed, i.e. they are non-stochastic. I think that means all our predictors, parameter estimates etc. are unconditional then, right? Might I even go so far that they are no longer random variables?  If on the other hand we accept that most regressors in economics say are stochastic because no outside force determined them with some experiment in mind. Econometricians then condition on these stochastic regressors.  How is this different from treating them as fixed?  I understand what conditioning is. Mathematically, it means we make all observations and inference conditional on that particular set of regressors and have no ambitions to say that inferences, parameter estimates, variance estimates etc. would have been the same had we seen a different realization of our regressors (such is the crux in time series, where each time series is only ever seen once).  However, to really grasp the difference between fixed regressors vs. conditioning on stochastic regressors, I am wondering if anyone here knows of an example of an estimation or inference procedure that is valid for say fixed regressors but breaks down when they are stochastic (and will be conditioned on).  I am looking forward to seeing those examples! Multiple Inheritance in java How to use dependency injection for Plugins/Blocks [\Drupal::formbuilder() and \Drupal::config()]? Triangle Inequality for norm integral $\|f\|_1=(\int_a^b [|f|^2+|f'|^2]\mathsf dx)^{1/2}$. Define $C_1^1[a,b]$ to be the space of continuously differentiable functions on $[a,b]$, with norm $$\|f\|_1=\left(\int_a^b[|f|^2+|f'|^2]\mathsf dx\right)^{1/2}.$$ Show that this is a proper definition of a norm. Is this normed space complete?  I'm stuck on the triangle inequality part. I'm having a hard time showing that $$\|f+g\|_1\leq \|f\|_1+\|g\|_1.$$ Any hints or solutions are greatly appreciated. Scorched3d will not launch Scorched3d worked then stopped. Unistalled and reinstalled did not help. Running Ubuntu 16.04.04LTS. I think it was after installing new release.  I think the problem is the Ubuntu 16.04.4LTS. The newer version has no Scorched3d in the Ubuntu Software Center. I have 3 systems. After updating to new version. Scorched3D will not install and work after updating.  ron@RonsComputer:~$ sudo objdump -p $(type -p scorched3d) | grep NEEDED  NEEDED libwx_gtk2u_adv-3.0.so.0  NEEDED libwx_gtk2u_core-3.0.so.0 NEEDED libwx_baseu-3.0.so.0 NEEDED libfreetype.so.6 NEEDED libz.so.1 NEEDED libSDL-1.2.so.0 NEEDED libSDL_net-1.2.so.0 NEEDED libexpat.so.1  NEEDED libstdc++.so.6 NEEDED libm.so.6 NEEDED libgcc_s.so.1 NEEDED libpthread.so.0 NEEDED libc.so.6   ron@ron-desktop ~ $ objdump -p $(type -p scorched3d) | grep NEEDED | awk '{print $2}' | xargs -n 1 dpkg -S  libwxgtk3.0-0v5:amd64: /usr/lib/x86_64-linux-gnu/libwx_gtk2u_adv-3.0.so.0.2.0 libwxgtk3.0-0v5:amd64: /usr/lib/x86_64-linux-gnu/libwx_gtk2u_adv-3.0.so.0 libwxgtk3.0-0v5:amd64: /usr/lib/x86_64-linux-gnu/libwx_gtk2u_core-3.0.so.0.2.0 libwxgtk3.0-0v5:amd64: /usr/lib/x86_64-linux-gnu/libwx_gtk2u_core-3.0.so.0 libwxbase3.0-0v5:amd64: /usr/lib/x86_64-linux-gnu/libwx_baseu-3.0.so.0.2.0 libwxbase3.0-0v5:amd64: /usr/lib/x86_64-linux-gnu/libwx_baseu-3.0.so.0 libfreetype6:amd64: /usr/lib/x86_64-linux-gnu/libfreetype.so.6.12.1 libfreetype6:i386: /usr/lib/i386-linux-gnu/libfreetype.so.6 libfreetype6:amd64: /usr/lib/x86_64-linux-gnu/libfreetype.so.6 libfreetype6:i386: /usr/lib/i386-linux-gnu/libfreetype.so.6.12.1 zlib1g:i386: /lib/i386-linux-gnu/libz.so.1.2.8 zlib1g:amd64: /lib/x86_64-linux-gnu/libz.so.1 zlib1g:i386: /lib/i386-linux-gnu/libz.so.1 zlib1g:amd64: /lib/x86_64-linux-gnu/libz.so.1.2.8 libsdl1.2debian:amd64: /usr/lib/x86_64-linux-gnu/libSDL-1.2.so.0.11.4 libsdl1.2debian:i386: /usr/lib/i386-linux-gnu/libSDL-1.2.so.0 libsdl1.2debian:i386: /usr/lib/i386-linux-gnu/libSDL-1.2.so.0.11.4 libsdl1.2debian:amd64: /usr/lib/x86_64-linux-gnu/libSDL-1.2.so.0 libsdl-net1.2:amd64: /usr/lib/x86_64-linux-gnu/libSDL_net-1.2.so.0 libsdl-net1.2:i386: /usr/lib/i386-linux-gnu/libSDL_net-1.2.so.0 libsdl-net1.2:amd64: /usr/lib/x86_64-linux-gnu/libSDL_net-1.2.so.0.8.0 libsdl-net1.2:i386: /usr/lib/i386-linux-gnu/libSDL_net-1.2.so.0.8.0 libexpat1:i386: /lib/i386-linux-gnu/libexpat.so.1.6.0 libexpat1:amd64: /lib/x86_64-linux-gnu/libexpat.so.1 libexpat1:amd64: /lib/x86_64-linux-gnu/libexpat.so.1.6.0 libexpat1:i386: /lib/i386-linux-gnu/libexpat.so.1 libstdc++6:amd64: /usr/share/gdb/auto-load/usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.21-gdb.py libstdc++6:i386: /usr/lib/i386-linux-gnu/libstdc++.so.6 libstdc++6:amd64: /usr/lib/x86_64-linux-gnu/libstdc++.so.6 libstdc++6:amd64: /usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.21 libstdc++6:i386: /usr/lib/i386-linux-gnu/libstdc++.so.6.0.21 libstdc++6:i386: /usr/share/gdb/auto-load/usr/lib/i386-linux-gnu/libstdc++.so.6.0.21-gdb.py libc6:amd64: /lib/x86_64-linux-gnu/libm.so.6 libc6:i386: /lib/i386-linux-gnu/libm.so.6 libgcc1:amd64: /lib/x86_64-linux-gnu/libgcc_s.so.1 libgcc1:i386: /lib/i386-linux-gnu/libgcc_s.so.1 libc6:i386: /lib/i386-linux-gnu/libpthread.so.0 libc6:amd64: /lib/x86_64-linux-gnu/libpthread.so.0 libc6:i386: /lib/i386-linux-gnu/libc.so.6 libc6:amd64: /lib/x86_64-linux-gnu/libc.so.6 ron@ron-desktop ~ $ Probability of asymmetric random walk returning to the origin Consider the random walk $S_n$ given by $ S_{n+1} =  \left\{   \begin{array}{l}     S_n+2 &amp; \text{with probability $p$}\\     S_n - 1 &amp; \text{with probability $1-p$}   \end{array} \right. \ $  Assume that $S_0 = n &gt;0 $. What is the probability of eventually reaching the the point $0$?  Seems that the probability for this must be less than one; since it is not symmetric, it is not guaranteed to reach the origin if $p&gt;0.5$. It also seems like the positive starting value not being at the origin matters too, but I'm not sure how to compute the probability of eventually reaching the origin. Inversion/non-inversion in wh-questions with long phrases after the wh-words Can a sentence like this:      "I don't know who the first man that made such and such thing in such and such place was,"    be grammatically correct if we don't put "was" at the end of the long phrase, that is, if we write:      "I don't know who was the first man that made such and such thing in such and such place"?    I can see in Google Books examples that in such cases the verb is often put after the wh-word, but I don't know if there is a grammar rule to support this. Some examples:  "We do not know who was the first man who ascended above a poor and humble people to become Egypt's first king ..."  "... we do not know what was the ultimate judgment of the various members of the community ..."  "I do not know who was the first to suggest a connection between the problem of free will and the breakdown ..."  "I do not know what was the date of this change in me, nor of the train of ideas ..."  "We do not know what was the primitive text from which Codex Bezae derived its Latin or its Greek ..."  "We do not know what was the practice in the days of the monarchy, but the story of Athaliah shows ..." Why are new sites classified as "uncategorized"? How do you prove that $\sum\limits_{n=0}^{\infty}{2n \choose n}x^n=(1-4x)^{-1/2}$? I tried to identify the sum as a binomial series, but the $4$ and the $-1/2$ puzzle me. (This series arises in studying the first passage time of a simple random walk.) I (as a middle-school student) was wondering how virtual particles even conserve energy of the entire system? I don't mean just the particle's energy, but conservation with respect to the surroundings?  Let me explain more, Einstein proved that $E = mc^2$ and equivalently, we can say $m = \frac{E}{c^2}$ . We however know mass causes curvature in space-time (gravity well). Now that statement being completely valid we can use Quantum Fluctuation, implying energy and time can be related by the relation:  $\Delta{E}\Delta{t}\approx\frac{\hbar}{2}$ and by that simple relation we can make the following points:   As the energy increases, the time allowed to be "borrowed" decreases, before it gives it back to the universe. As time increases, the energy allowed to be "borrowed" decreases.    These are completely satisfactory points I've made, I believe.  Now, I have read that the vacuum is filled with constantly bubbling virtual particles that get created from the energy "borrowed" by the above relation and is destroyed again, which satisfies the energy conservation laws.   This seems to imply that  in the short time the virtual particle exists, they must have a very small mass which is: $m_{1} = \frac{\Delta{E}}{c^2}$ and using basic classical mechanics rather than GR (for sake of simplicity) we calculate that the gravitational force mediated by this short-lived virtual particle;  $F_{g}= G\frac{m_1 * m_x}{r^2}$   where $m_x$ is an particle\mass in question. Nevertheless since we know the force set upon an object moves the object in a direction, we can say it would increase its kinetic energy by this factor: $F_g = \frac{1}{2}mv^2$ which is equal to $G\frac{m_1 * m_x}{r^2} = \frac{1}{2}mv^2$.  Surely, this implies that every time quantum fluctuations happen, energy of real-particles\masses increases and therefore violates energy conservation, but what prevents this violation from taking place?  If virtual particles are not really present and interact with objects like I thought, how can Hawking radiation (currently a large concept in black hole physics) then be accepted in physics community? What is the correct formula for gravitational time dilation for a satellite in a circular orbit? In the Wikipedia article on  I see two formulae for the gravitational time dilation. One contains $\sqrt{1 - r_0/r}$ but the other $\sqrt{1 - 1.5 r_0/r}$. What formula should I use to calculate the time dilation due to gravity inside a satellite? The speed induced time dilation is of course just special relativity.  With the first of these two formulas I can perfectly reproduce the graphs on time dilation as a function of $r$,  I find that the two contributions to time dilation cancel at 1.5 Earth radii, all numbers are OK... But why not the second formula? Biasing circuit - Voltage follower circuit I am using , which is and Bias controller/sequencer. I am using this for Providing gate voltage and drain voltage to the . In the datasheet, it is mentioned that the module with combination of EVM can be used in two applications. Application Option 1: Fixed negative gate biasing with pulsed drain biasing. Application Option 2: Pulsed negative gate biasing with pulsed drain biasing. I am trying to design both applications on a single board. The second option for future use. For the 1st application option, he has mentioned a few pins as No connection and he has used those NC pins on the 2nd application.  The issue I am facing:- They have used voltage followers for providing a low impedance output path for pin number 3(GCO). I have reverse-engineered the Ckt from the below-attached image, but I am unable to identify the voltage follower they have used. Pin number 2 of the voltage follower has been connected to pin number 2 (NC/GCP) of the Module. There has been no description of this pin number. I am guessing these:-  Pin numbers 1 and 4 are connected together and output is provided through them. Pin number 5 is +Ve supply hence connected to GND(Highest +Ve supply)? Pin number 3 is connected to -8V Pin number 2 is connected to pin number 2 of MABC-001000-DP000L, which I am unable to understand.  I have mailed component manufacturer regarding full schematic, till now I haven't heard from them. Can anybody help me with this? Thanks in Advance. Low-resolution pic of EVM. I don't think it helps in any way.   Layout Image Finding what's using all the space in *nix Which sequence of commands will tell me which files are the largest starting from a particular directory, including all sub directories? I want to know where all the space went.  Preferably just with regular unix'y commands.  If possible, try to keep it compatible with Sun OS 5.10 (perhaps in addition to regular Linux answers, not as a replacement, to keep it as general as possible.) How to reinstall yum? I made a big mistake: I removed yum. So now when I for example run the following it gives me an error:  $ yum clean all yum command not found.   I can download the package succesfully:  wget mirror.centos.org/centos/6/os/i386/Packages/yum-3.2.29-40.el6.centos.noarch.rpm --2014-01-15 15:42:59--  http://mirror.centos.org/centos/6/os/i386/Packages/yum-3.2.29-40.el6.centos.noarch.rpm Resolving mirror.centos.org... 192.133.139.3 Connecting to mirror.centos.org|192.133.139.3|:80... connected. HTTP request sent, awaiting response... 200 OK Length: 1019540 (996K) [application/x-rpm] Saving to: “yum-3.2.29-40.el6.centos.noarch.rpm.1”  100%[====================================================================================================================&gt;] 1,019,540    649K/s   in 1.5s  2014-01-15 15:43:01 (649 KB/s) - “yum-3.2.29-40.el6.centos.noarch.rpm.1” saved [1019540/1019540]   Trying to install the downloaded package gives the following error:  # rpm -ivh yum-3.2.29-40.el6.centos.noarch.rpm Preparing...                ########################################### [100%]     file /usr/lib/python2.6/site-packages/yum/__init__.py from install of yum-3.2.29-40.el6.centos.noarch conflicts with file from package yum-3.2.29-30.el6.centos.noarch [...] file /usr/share/yum-cli/yummain.pyo from install of yum-3.2.29-40.el6.centos.noarch conflicts with file from package yum-3.2.29-30.el6.centos.noarch   There is no directory "yum" in /usr/bin.  When I use the command "rpm -qa | grep yum".  yum-metadata-parser-1.1.2-16.el6.x86_64 yum-plugin-fastestmirror-1.1.30-14.el6.noarch yum-3.2.29-30.el6.centos.noarch   The distro is CentOS 6.3. How can I reinstall yum?