Questions without a question mark (New Yorker)
When is it appropriate to end a question without a question mark?
I read somewhere that according to relativity, it is possible - involving black holes and other stuff - to jump into the past. Is it possible for anything to go back in time either continuously or by jumping? I am trying to model a violin belly and I am intrigued, how is it possible to make faces with soft / rounded edges?    The edges I do are totally straight (see the blue amoeba).  Also, do you have some idea on how to avoid the edge loops getting too "compressed" in the middle of the model (see the red amoeba) ?    I know the Subdivision surface modifier, but I want curved edges after applying the modifier... like in this picture :  Any help will be very appreciated. Thank you in advance!  Marcos  2nd part  In fact, I've tryied to model using nurbs and bezier curves, but I wasn't able to find any tool similar to loft that works with curves, then I was forced to convert it in meshes, the results were not terrific and I've started to move the vertices manually, a real pain... Unlike a guitar, each edge loop is on a diferente elevation on z axis and I have to keep the original dimensions, So I have to be extremely careful when using the subdivision suface modifier. I've already modeled this think on three different CAD softwares, but the meshes are far from good... I want to improve the edge loops, but it will be a long path... Thank you again. When my receiver that I have hooked up to my pc turns on it causes my monitors to turn black is there a way to stop this? Can US stocks list on one stock exchange but trade on other US stock exchanges? I am trying to understand how the US stock market works. From my understanding, there is one stock exchange where a company is &quot;listed&quot;. This stock exchange listing requires the company to adhere to the regulations of the stock exchange where it is listed. Once a company is &quot;listed&quot;, its shares can start to trade on any stock exchange. For example, once a company lists on NASDAQ, its shares can be traded on NASDAQ, NYSE, Boston Stock Exchange, Philadelphia Stock Exchange, National Stock Exchange, EDGX Exchange, EDGA Exchange, NYSE Arca, etc. Is my understanding correct? Is it true that once a stock is listed on a US stock exchange, the stock can then trade on any US stock exchange? Consider the Level 2 quotes for Microsoft (NASDAQ: MSFT). Microsoft is only listed on NASDAQ, but it also trades on the NYSE and other stock exchanges:  My questions are:  Does this mean that companies only need to be listed on one stock exchange in order for their stock to trade on other stock exchanges?  If so, do companies need to adhere to the &quot;listing requirements&quot; of all the stock exchanges where their stock is traded, even though they are not &quot;listed&quot; on those stock exchanges? Does Microsoft have to follow the listing requirements of the NYSE even though it is not listed there?  If stocks can trade on any US stock exchange regardless of which US stock exchange the stock is listed on, why don't NYSE-listed companies reduce their yearly listing fees by listing on NASDAQ instead? How can I do a line break (line continuation)? I have a long line of code that I want to break up among multiple lines. What do I use and what is the syntax?  For example, adding a bunch of strings,  e = 'a' + 'b' + 'c' + 'd'   and have it in two lines like this:  e = 'a' + 'b' +     'c' + 'd' Javascript to check whether a checkbox is being checked or unchecked Do small title edits constitute trivial edits? Differentiability implying continuity Theorem: If $f$ is finitely differentiable at $c$, then $f$ is also continuous at $c$.  But according to the definition, for a function to be differentiable at $c$, it need not even be defined at $c$, just that it should have a finite value in the vicinity of $c$.    My question: If function is not defined at $c$, how can it be continuous at $c$?  For example, say we have a straight horizontal line function which is broken at $x=1$, the function is defined at all the points except $x=1$, it has a finite value at all the points except $x=1$, since it is having a value in the nearby region of $x=1$ we say that it is differentiable at $x=1$ but can we say that it is continuous at $x=1$? Lead in ice block This is a strange question I would like to have some explanation accompanied with:  We have an ice block, with in it a lead block. This entire block is put into a glass of water, resulting in a rise of water level until the edge of the glass. The block stays floating on the surface. What will happen with the water level when the ice melts?  The answer is that it will drop, but how is this even true?? My thoughts are: - block floats on water, so rho(block) &lt; rho(water) - Archimedes law, the Fg of block = Fg of water pushed away. - Since a smaller volume of water has equal mass (and so Fg) to block, and ice is less dense than water, when it melts, no mass is lost, so it will take in less space??? Please help me with this point of thinking. Radius of circumscribed circle of triangle as function of the sides Given the length ot the sides $a , b$ and $c$  of $ \triangle ABC$.  What is the length of the radius of the circumcribed circle?  After some formula substitution I came to the monster formula:  $$ \frac {a b c}{\sqrt{2a^2b^2+2a^2c^2+2b^2c^2-a^4-b^4-c^4}} $$  Can this formula be simplified? How can I make my touchpad scroll either vertically or horizontally, but not both? If I'm browsing the internet and a page has both horizontal and vertical scroll bars it becomes really irritating to scroll with my touchpad. It keeps scrolling horizontally as well as vertically!  I'm using Ubuntu 16.04  and below are touchpad settings  Device 'SynPS/2 Synaptics TouchPad':     Device Enabled (160):   1     Coordinate Transformation Matrix (162): 1.000000, 0.000000, 0.000000, 0.000000, 1.000000, 0.000000, 0.000000, 0.000000, 1.000000     Device Accel Profile (282): 1     Device Accel Constant Deceleration (283):   2.500000     Device Accel Adaptive Deceleration (284):   1.000000     Device Accel Velocity Scaling (285):    12.500000     Synaptics Edges (286):  1769, 5431, 1652, 4658     Synaptics Finger (287): 25, 30, 0     Synaptics Tap Time (288):   180     Synaptics Tap Move (289):   242     Synaptics Tap Durations (290):  180, 100, 100     Synaptics ClickPad (291):   0     Synaptics Middle Button Timeout (292):  75     Synaptics Two-Finger Pressure (293):    282     Synaptics Two-Finger Width (294):   7     Synaptics Scrolling Distance (295): 200, 200     Synaptics Edge Scrolling (296): 0, 0, 0     Synaptics Two-Finger Scrolling (297):   1, 1     Synaptics Move Speed (298): 1.000000, 1.750000, 0.036300, 0.000000     Synaptics Off (299):    1     Synaptics Locked Drags (300):   0     Synaptics Locked Drags Timeout (301):   5000     Synaptics Tap Action (302): 2, 0, 0, 0, 1, 3, 0     Synaptics Click Action (303):   1, 1, 0     Synaptics Circular Scrolling (304): 0     Synaptics Circular Scrolling Distance (305):    0.100007     Synaptics Circular Scrolling Trigger (306): 0     Synaptics Circular Pad (307):   0     Synaptics Palm Detection (308): 0     Synaptics Palm Dimensions (309):    10, 200     Synaptics Coasting Speed (310): 21.120001, 50.000000     Synaptics Pressure Motion (311):    30, 160     Synaptics Pressure Motion Factor (312): 1.000000, 1.000000     Synaptics Resolution Detect (313):  1     Synaptics Grab Event Device (314):  0     Synaptics Gestures (315):   1     Synaptics Capabilities (316):   1, 0, 1, 1, 1, 1, 1     Synaptics Pad Resolution (317): 83, 46     Synaptics Area (318):   0, 0, 0, 0     Synaptics Noise Cancellation (319): 8, 8     Device Product ID (277):    2, 7     Device Node (278):  "/dev/input/event6" Is it worth buying a 5D Mark I or an EOS 1Ds II today? Why are some of my screen-recording/capturing/sharing applications (or app features) not working in Ubuntu 17.10 (and later releases)? In the sentence      It's one of the best films that has/have ever been made   What should the verb agreement be? If $(a_n)\subset[0,\infty)$ is non-increasing and $\sum a_n<\infty$, then $\lim{n a_n} = 0$ I'm studying for qualifying exams and ran into this problem.  Show that if $\{a_n\}$ is a nonincreasing sequence of positive real numbers such that $\sum_n a_n$ converges, then $\lim_{n \rightarrow \infty} n a_n = 0$.  Using the definition of the limit, this is equivalent to showing \begin{equation} \forall \varepsilon &gt; 0 \; \exists n_0 \text{ such that } |n a_n| &lt; \varepsilon \; \forall n &gt; n_0 \end{equation} or \begin{equation} \forall \varepsilon &gt; 0 \; \exists n_0 \text{ such that } a_n &lt; \frac{\varepsilon}{n} \; \forall n &gt; n_0 \end{equation} Basically, the terms must be bounded by the harmonic series. Thanks, I'm really stuck on this seemingly simple problem! Prove $(a^2+b^2)(c^2+d^2)\ge (ac+bd)^2$ for all $a,b,c,d\in\mathbb{R}$. Prove $(a^2+b^2)(c^2+d^2)\ge (ac+bd)^2$ for all $a,b,c,d\in\mathbb{R}$.  So $(a^2+b^2)(c^2+d^2) = a^2c^2+a^2d^2+b^2c^2+b^2d^2$  and $(ac+bd)^2 = a^2c^2+2acbd+b^2d^2$  So the problem is reduced to proving that $a^2d^2+b^2c^2\ge2acbd$ but I am not sure how to show that Avoid synchronized(this) in Java? Expected number of rolling a pair of dice to generate all possible sums A pair of dice is rolled repeatedly until each outcome (2 through 12) has occurred at least once. What is the expected number of rolls necessary for this to occur?  Notes: This is not very deep conceptually, but because of the unequal probabilities for the outcomes, it seems that the calculations involved are terribly messy.  It must have been done already (dice have been studied for centuries!) but I can't find a discussion in any book, or on line. Can anybody give a reference? Jquery change image on rollover with fade What do you call something that is not first in a sequence? Is there a word to describe something that is not the first element in a sequence, but can be in any other position? A synonym of "not first", in fact.     This element is __ in this sequence.