The more time you spending in measuring your experiment (thus standard deviation will become smaller) the more precisely you will measure energy of this system.... energy time uncertainly principle implies this.... and in most systems (i have seen,or may be all systems ) the lowest possible energy is ground state energy, this energy cannot be removable.. for example in a infinit square well .. Then how can ''universe from nothing'' i would say sentence makes sense? if there is uncertainly how there is something like nothing... if minimum energy possible is ground state energy..how nothing(no energy exist)???
In popular science books and articles, I keep running into the claim that the total energy of the Universe is zero, "because the positive energy of matter is cancelled out by the negative energy of the gravitational field".  But I can't find anything concrete to substantiate this claim. As a first check, I did a calculation to compute the gravitational potential energy of a sphere of uniform density of radius $R$ using Newton's Laws and threw in $E=mc^2$ for energy of the sphere, and it was by no means obvious that the answer is zero!  So, my questions:   What is the basis for the claim &ndash; does one require General Relativity, or can one get it from Newtonian gravity? What conditions do you require in the model, in order for this to work? Could someone please refer me to a good paper about this?
Discriminant analysis vs logistic regression zsh scripting - How do I NOT match a pattern in filename generation? I have thus far avoided the nightmare that is testing multi-threaded code since it just seems like too much of a minefield.  I'd like to ask how people have gone about testing code that relies on threads for successful execution, or just how people have gone about testing those kinds of issues that only show up when two threads interact in a given manner?  This seems like a really key problem for programmers today, it would be useful to pool our knowledge on this one imho. Earth Engine convert list with coordinates and values into a feature collection for export I need to create a feature collection from a list containing coordinates and band values.  These are extracted from a landsat image as shown in this linked script.    I'm unable to find a solution in creating a feature collection.  Here is the tail end code.  var valuesList = joinedImage.reduceRegion({   reducer: ee.Reducer.toList(4),   geometry: myGeometry }).values().get(0);  var feature = ee.Feature(null, valuesList);   // Wrap the Feature in a FeatureCollection for export. var myFeatures = ee.FeatureCollection([feature]);   // Export the image, specifying scale and region. Export.table.toDrive(myFeatures, "data", "myData", "B4-B5",  "CSV");   This doesn't work, because it is clearly the wrong way to create the feature collection.  I've tried to create it similar to Rodrigo E. Principe's solution of mapping a Feature Collection but I can't seem to create the initial feature collection to start with. How can I keep low resolution textures pixelated? I have a problem. I am going to make a minecraft animation in blender. But when I put a minecraft texture on a 3d cube that is 16x16x16 it is very low resolution is there a way to get the texture in a better resolution or is there a way to make blender make the texture better?  I hope you have an answer. Thanks in advance Unsure whether to use "enquire" or "inquire" Where can I find gedit's backup files and how to open them? So, I just finished off the first part of an important task for school and today when I was going to continue, the document with my notes were gone. The only fragment I've got left of my file is the back up file, which doesn't show in the folder where I saved the document, but I can search for it.  Is there anyway which allows me to open the back up file, save it as a text file and continue my task? I don't really have the time for running restoring tools, which never has helped me in a satisfactory way anyway.  I wrote the document in gedit and my version of Ubuntu is 12.10. Why can't I destroy or place blocks? I'm playing on a Survival world with cheats on, "easy" difficulty, and at night in-game. I didn't have a sword or anything to make a sword with, and I was starving, so I switched to Creative to give myself a stack of food and a bed to set my spawn point. When I switched back to Survival, I couldn't destroy or place blocks. I'm on single player, and my Internet is fine, and I can destroy blocks still if I switch to creative. I've tried resetting the button one, and reloading the map, and it still doesn't work. I've even tried deleting everything I gave myself in Creative. This happened before on a different world and I ended up deleting it.  This only happens on this world. How do I fix it?  If I know I'm in the correct game mode, what else can cause this?  Are there different causes in multiplayer? Here is my problematic code:  \begin{tikzpicture} \draw  (0,0)  to [bend left=20] (3,3) node[midway] {midway label}; \end{tikzpicture}   I wanted to put a label midway of the line, but instead the label is at (0,0).  If I remove [bend left=20], the line is not bent, and the label still misplaced. If I remove to and replace it by --, then it works fine, but my line is not bent any more.  \begin{tikzpicture} \draw (0,0) -- (3,3) node[midway] {midway label}; \end{tikzpicture}   Works fine.  The problem occurs with MacTeX 2011 and MacTeX 2012. I'm writing a script and I would like to pass the results from bc into a variable. I've declared 2 variables (var1 and var2) and have given them values.  In my script I want to pass the results from bc into another variable say var3 so that I can work with var3 for other calculations.  So far I have been able write the result to a file which is not what I'm looking for and also I've been able to echo the result in the terminal but I just want to pass the result to a variable at moment so that I can work with that variable.  echo "scale=2;$var1/var2" | bc Proving a limit of a trigonometric function: $\lim_{x \to 2/\pi}\lfloor \sin \frac{1}{x} \rfloor=0$ $$\lim_{x \to \frac{2}{\pi}}\lfloor \sin \frac{1}{x} \rfloor=0$$    I need to prove the limit of this using the $\epsilon - \delta $ way but I don't know how to find $\delta$ when I'm given a trigonometric function I know only how to do it with polynomial functions What is the normal operating temperature for the MacBook (2016 generation)? "Speak to" vs. "Speak with" What are the differences between these two phrasal verbs and what are the best situations to use each? Uninstalling/reinstalling QGIS plugin where uninstall is disabled? Plugin Raster->TerrainAnalysis->slope which had initially worked, started showing what another questioner referred to as a "crazy histogram":   Before finding his question and the answer, I endeavored to uninstall and reinstall the plugin.  I found/still find (QGIS 2.0.1, now upgraded to QGIS 2.4, on Ubuntu 14.04), the plugin "uninstall" button grayed out/disabled.  It's working, but I am worried about having a plugin I installed that does not offer an option to be uninstalled.  Failing anything else I would be tempted to use the path information to rename the .so library and see if it disappeared. We know that any particle moving at speed of light will have infinite mass.  Since even Light has particles. Then what is the size of the Particle? How to imagine this with the mass of light particles. I would like to know how I can get the value of a node with the following paths:   config/global/resources/default_setup/connection/host config/global/resources/default_setup/connection/username config/global/resources/default_setup/connection/password config/global/resources/default_setup/connection/dbname   from the following XML:  &lt;?xml version="1.0"?&gt; &lt;config&gt;     &lt;global&gt;         &lt;install&gt;             &lt;date&gt;&lt;![CDATA[Tue, 11 Dec 2012 12:31:25 +0000]]&gt;&lt;/date&gt;         &lt;/install&gt;         &lt;crypt&gt;             &lt;key&gt;&lt;![CDATA[70e75d7969b900b696785f2f81ecb430]]&gt;&lt;/key&gt;         &lt;/crypt&gt;         &lt;disable_local_modules&gt;false&lt;/disable_local_modules&gt;         &lt;resources&gt;             &lt;db&gt;                 &lt;table_prefix&gt;&lt;![CDATA[]]&gt;&lt;/table_prefix&gt;             &lt;/db&gt;             &lt;default_setup&gt;                 &lt;connection&gt;                     &lt;host&gt;&lt;![CDATA[localhost]]&gt;&lt;/host&gt;                     &lt;username&gt;&lt;![CDATA[root]]&gt;&lt;/username&gt;                     &lt;password&gt;&lt;![CDATA[pass123]]&gt;&lt;/password&gt;                     &lt;dbname&gt;&lt;![CDATA[testdb]]&gt;&lt;/dbname&gt;                     &lt;initStatements&gt;&lt;![CDATA[SET NAMES utf8]]&gt;&lt;/initStatements&gt;                     &lt;model&gt;&lt;![CDATA[mysql4]]&gt;&lt;/model&gt;                     &lt;type&gt;&lt;![CDATA[pdo_mysql]]&gt;&lt;/type&gt;                     &lt;pdoType&gt;&lt;![CDATA[]]&gt;&lt;/pdoType&gt;                     &lt;active&gt;1&lt;/active&gt;                 &lt;/connection&gt;             &lt;/default_setup&gt;         &lt;/resources&gt;         &lt;session_save&gt;&lt;![CDATA[files]]&gt;&lt;/session_save&gt;     &lt;/global&gt;     &lt;admin&gt;         &lt;routers&gt;             &lt;adminhtml&gt;                 &lt;args&gt;                     &lt;frontName&gt;&lt;![CDATA[admin]]&gt;&lt;/frontName&gt;                 &lt;/args&gt;             &lt;/adminhtml&gt;         &lt;/routers&gt;     &lt;/admin&gt; &lt;/config&gt;   Also I want to assign that value to the variable for further use. Let me know your idea. During graduate studies online application submission period, is there any preference given for an applicant if he/she submits his application at the beginning of that period compared with someone who submits his/her application couple of hours before the deadline?  Or as long as the applications are complete there is absolutely no difference! I've been to South Korea a few times already and always enjoy it but I've always had an onward ticket before.  Now I need to fly home from a trip that's lasted over a year, but I still want to take my time and keep my options open.  There's a good choice of cheap flights from Istanbul to Seoul and from Seoul I can't decide yet whether to fly straight home or take a ferry to China, hitchhike to Guangzhou, and get a cheap flight home from there.  I can't really just buy the China-Australia flight now because I'm not sure yet whether I'll be able to get the Chinese visa easily enough or how long my remaining money will last.  I know Korea, like most countries, has rules saying you need an onward ticket, but in my experience many countries never try to verify that you have this ticket unless you fit some profile. So in this instance I would find first-hand knowlegde much more informative that pointers to a government website.  In practice does South Korea admit tourists with one-way tickets? I'm having some trouble understanding cosets.  If I understand it correctly, cosets form a partition. So, if I have $|G:H| = 2$, then $G = H \cup xH$. Right?  In an exercise, I'm asked the following:  "For $G$ group and $H \le G$ such that $|G:H| = 2$, prove that $x^2 \in H$ for any $x \in G$"  If $x \in H$, then $x^2 \in H$ because $H$ is a group. But, if $x \notin H$, then $x \in gH$ for any $g \in G$, right? Then $x^2$ = $(gh)^2$ but I can't see why this is in $H$.  Can you give me some hint? Thanks for stopping by. Split String Function