Is an electron completely determined by its mass? What I mean is, could a chunk of matter be &quot;whittled down&quot; or broken off from a larger chunk of matter to the point where it has the mass either exactly of an electron or close to that and in the former case, would it have to be an electron and if somehow the charge of the original piece of matter was neutral or positive would the electron-sized piece suddenly become a negatively charged electron or I guess a positron perhaps. And in the latter case, would the chunk somehow &quot;degenerate&quot; into an electron, shedding the extra mass? I know particles can be created from like laser beams experimentally but it seems like nothing other than know particles are ever created -- never is there just a tiny piece of matter with no characteristics like charge and whatever else electrons/positrons have.
Fundamental particles identical or just differences very small? I have read that all electrons are identical and I assume the same for protons, etc. That is, all electrons are of the exact same mass and charge.  But do we really know this? Could there be slightly heavier electrons with slightly higher charge or is there a reason why such particles could not exist or would be unstable?
How about a "Vote not to close" option to counter the "Vote to close"? My request is simple: Many times, there will be a question where some people feel like it should be closed. At the same time, I'll feel like it's a perfectly legit question, and it should therefore NOT be closed. Right now, I have to wait till it gets enough close votes (which it always does for some reason, as soon as 1 or 2 people vote to close, e/o else decides to vote as well) and then vote to re-open. How about, as soon as there's one vote to close, there should be an option to counter the close vote, something like "vote not to close" or whatever. This would then bring the "Vote to close" number down by one. Only when the vote to close outnumbers the vote not to close by 5, that's when a question is indeed closed. Any thoughts? Algebraic Proof that $\sum\limits_{i=0}^n \binom{n}{i}=2^n$ Tax considerations for selling a property below appraised value to family? I own a property that recently appraised for $350,000 in the state of Maryland that I purchased for $300,000 7 years ago. I wish to sell this property for a value of $240,000. Here are my questions:   Is this legal? The state of Maryland has a transfer/recordation tax of 1.5% for each, the buyer and seller. Would this be computed on the appraised or sale value? Will this pose any problem if the buyer needs financing? Would I be able to deduct a capital loss on my tax return?     From comments: I should have mentioned - the buyer is a sibling. How can I query SEDE for tags I've created? How can I query the  for tags I've created? How to change background colour in texworks I am using texworks for the first time, I want to change the background of the editor from dark to white, as the code is not visible in dark background. I am using texworks in Manjaro Linux on GNOME desktop environment. Please help me. counting triangles in a graph or its complement Given a simple graph $G$ [no loops or parallel edges] on six vertices,  let $G^c$ denote its complement. It is known that either $G$ or $G^c$ must contain a triangle  $T$ in it. [An example of a Ramsey number I think.]   My question came up when I tried to find such a graph on six vertices  which had only one $T$ in it or its complement.  I believe if I did things right there are none of these. This I tried to check by drawing a copy of each graph $G$  on six vertices which has a $T$ in it,  and then looking at the complements to see if any had  no $T$'s in them. I found none.  One way to pose my question for a general number $n$ of vertices  is then as follows: Consider the set of all graphs $G$ on $n$ vertices,  and for each one construct $G^c.$  Count the number of $T$ in $G$ and add that to the number of $T$ in $G^c.$  Finally find the minimal such sum for the given $n$  and call that say $M(n).$ So my above six vertex conjecture  is that $M(6)=2.$   By considering a cycle graph on five vertices we find $M(5)=0.$   So going further one could ask if anything is known  about this minimum function $M(n)$ for larger $n$ [such as bounds, etc.] And does it have a name?  I would also like to see a simpler way to handle the six vertex case, one not involving drawing all the graphs. I'm concerned about an app on my child's phone. I saw an app icon in the notification area that looked strange (Andy Android head, slightly tilted as its icon).  How can I find out what app it is from just having seen that icon in the notification bar? Find three Poisson-distributed random variables, pairwise independent but not mutually independent Is there a destructor for Java? Is there a destructor for Java? I don't seem to be able to find any documentation on this. If there isn't, how can I achieve the same effect?  To make my question more specific, I am writing an application that deals with data and the specification say that there should be a 'reset' button that brings the application back to its original just launched state. However, all data have to be 'live' unless the application is closed or reset button is pressed.  Being usually a C/C++ programmer, I thought this would be trivial to implement. (And hence I planned to implement it last.) I structured my program such that all the 'reset-able' objects would be in the same class so that I can just destroy all 'live' objects when a reset button is pressed.  I was thinking if all I did was just to dereference the data and wait for the garbage collector to collect them, wouldn't there be a memory leak if my user repeatedly entered data and pressed the reset button? I was also thinking since Java is quite mature as a language, there should be a way to prevent this from happening or gracefully tackle this. PPA seems to be constantly offline. Whenever I use sudo apt-get update, this error is shown:  W: Failed to fetch http://ppa.launchpad.net/ 404  Not Found   How do I fix these errors? Infinite metric space has open set $U$ which is infinite and its complement is infinite Let $(X,d)$ be a metric space where $X$ is an infinite set. Prove that the space has an open set $U$ such that both $U$ and its complement are infinite sets.   I have considered if $d$ is the discrete metric, then one such $U$ exists. But if $d$ is not discrete, how do we find such $U$? Recovering data from a phone stuck in restore mode I have an iphone 4 that is stuck in restore mode after trying to update to ios 6 wirelessly.  Unfortunately, I do not have a recent itunes backup of this phone.  Is there any way to recover my photos from this device before I try to restore it?  Will restoring it wipe all the data on the phone? Prove that there exists at least one $x_0\in\mathbb{R}$, such that $f(x_0)+f''(x_0)=0$ Let $f:\mathbb{R}\to\mathbb{R}$ be a function, two times   differentiable with $\left|f(x)\right|\leq1,\forall x\in\mathbb{R}$   and $f^2(0)+\left(f'(0)\right)^2=4$. Prove that there exists at least   one $x_0\in\mathbb{R}$, such that $f(x_0)+f''(x_0)=0$.   I have tried the usual Rolle method by $e^x$, but didn't go far... Any help available? I want to render an image as a background image via an inline style in twig. I created a field called bg_image and attached it to the standard plain page.  After fiddling around for hours I was able to get the Image URL in node.html.twig  {{ file_url(node.field_bg_image.0.entity.uri.value) }}   but I could not get it to work inside field--field-bg_image.html.twig  Can I get the node from there anyhow, so I can then get the image?  How can I get the image URL to use as inline style? I thought maybe I can pass a variable from field--field-bg_image.html.twig to image.html.twig and then just render  {{ uri }}   instead of  &lt;img{{ attributes.addClass(classes) }} /&gt;   but I could not get it to pass the variable there unless I use includes  {% include 'image.html.twig' with {'image': image, 'isFromField': isFromField} %}   (isFromField is true, when it comes from the field--field-bg_image.html.twig) But that didn't work either. The Image was never rendered that way.  Would be very glad if you can help - my php knowledge is very basic. Thanks Where is a good place to learn classical optics for high school competitions? Can suspended users post comments? Get notifications? What happens to their reputation? Can a full version of Ubuntu be Installed on a USB Drive? When I try to start Runescape I get an error message that says: CLassNotFoundException and lists Rs2Applet.class. How do I fix this so I can play? Reading Excel files from C# Is there a free or open source library to read Excel files (.xls) directly from a C# program?   It does not need to be too fancy, just to select a worksheet and read the data as strings. So far, I've been using Export to Unicode text function of Excel, and parsing the resulting (tab-delimited) file, but I'd like to eliminate the manual step. $(document) vs. $("document")