There is a cosmic microwave background, according to the Big Bang theory. There is also a cosmic neutrino background, at 1.945 K, yet to be discovered, according to the Big Bang theory. My question is: what is the cosmic graviton/gravitational background temperature?  If any, how could it be related to the neutrino or photon background temperatures?  Remark: Sometimes, some people distinguish between the stochastic gravitational wave background and the so-called primordial gravitational wave events. The answer to this question should also clarify what are these two GW and how could they be related to the hypothetical cosmic gravitational wave background.
The recent discovery by the LIGO made me wonder about this.  We know that there exists a CMBR, Cosmic Microwave Background Radiation, a blanket of electromagnetic energy covering the universe, made by the Big Bang.  But, the big bang was an explosive event. The huge "shockwave" made by it sent ripples in space time. (Primordial gravitational waves)  Wouldn't these ripples flood the universe creating sort of a Cosmic Gravitational Background Radiation (not exactly radiation)?  If such waves do flood the universe, couldn't a much more sensetive version of LIGO be able to detect this and use it as a contrast to create "gravitational telescopes"?
Allow embedded HTML5 YouTube video Where did the Q come from, before the Q Continuum? In the Star Trek Universe where did the Q come from? I mean before they were Q in the Q Continuum? In Star Trek Voyager you learn that the race is somewhat intolerant of individualism (in the episode of the Q Civil War) but Q also suggest they have always been Q. Is that statement true, have the Q always been the Q? or were they a race that evolved into omniscience? How to sum a variable by group For example, you're a fashion designer who wants to get the opinion of both a professional and someone who doesn't know much about fashion. What's a term for the latter person? New UI encourages askers to confirm or dispute duplicate votes , the banner shown to askers whose questions have attracted at least one duplicate close vote has a couple of new options:    If the author clicks the first button, they're shown a confirmation that clarifies the results of this action somewhat:    If they click "Ok", the question is instantly closed:    If, instead, they edit, they'll be offered this guidance:    ...and once an edit is submitted the choice will go away until another duplicate close-vote is cast.   In just the past day, 80 questions  network-wide have been closed in response to confirmation from the asker; edits by askers are up significantly as well.   We'll be monitoring the results to see if further adjustments are needed. A few open questions surrounding this change include:    Perhaps if the number of votes is below some threshold?   I'm posting this separately from  to allow room for discussion and . List all columns for a specified table How to prove this binomial identity $\sum_{r=0}^n {r {n \choose r}} = n2^{n-1}$? I am trying to prove this binomial identity $\sum_{r=0}^n {r {n \choose r}} = n2^{n-1}$ but am not able to think something except induction,which is of-course not necessary (I think) here, so I am inquisitive to prove this in a more general way.  The left side of an identity occurs while solving another problem (concerning binomial theorem) so I am more interested in deriving the right side from the left side, else I have to remember it now onward.  EDIT: I am more interested in an algebraic proof rather than combinatorial argument or something involving calculus (however I liked  and  solution), hence I am removing the combinatorics tag. "This webpage has a redirect loop" in Chrome but working fine on FF and IE? Show badges in user profile in iOS app When viewing a user's profile from the iOS app, it would be nice to be able to see what badges they have, instead of just the counts. What is the purpose of a serial number? Were any of the Elves in Tolkien twins? Thinking about the idea of Elves having low numbers overall, got me to wondering: as far as Tolkien's writing, could elves ever have twins?  As a "yes" answer, I need an example of twins (any of JRRT work). They must be full on Elves, not half-Men. As a "no" answer, has to be an explicit statement in his work stating Elves ALWAYS had one child at a time. Anything else is a "maybe, we don't know". How can I make a script (or make some changes) to allow me to turn the screen off in Ubuntu (12.04) whenever I want, the way thevscreen can be turned off in Cellphones?  And how can I make a combination of keys (a shortcut) to execute that script?  I want to conserve power.  I've seen this question    but there is no hotkey for it.  Moreover, in the answer, it is said that there are many ways to accomplish this so I'd like to know more. Finding the shortest distance between two lines I know how to find the distance between a point and a line, not between two lines.  Find the shortest distance between the lines $(-1,1,4) + t(1,1,-1)$ and $(5,3,-3) + s(-2,0,1)$  Any help would be appreciated. I read this story in the early 2000s, but it was a Chinese translation so the English version could be older.  The beginning is a bit like the Passengers movie: on a spaceship, a man woke up from stasis too early and found that he could not go back to sleep. So he has to spend his whole life on the spaceship, alone.  For some reason (technical or ethical), instead of waking other people up, he created a fantasy adventure story featuring a brave prince as a pastime. He did stories, and drawings all over the inside of the ship. Then he died, not knowing how people are going to respond to his work. Are these intended activities legal to do in the USA under the VWP? How do I address unchecked cast warnings? Eclipse is giving me a warning of the following form:     Type safety: Unchecked cast from Object to HashMap   This is from a call to an API that I have no control over which returns Object:  HashMap&lt;String, String&gt; getItems(javax.servlet.http.HttpSession session) {   HashMap&lt;String, String&gt; theHash = (HashMap&lt;String, String&gt;)session.getAttribute("attributeKey");   return theHash; }   I'd like to avoid Eclipse warnings, if possible, since theoretically they indicate at least a potential code problem.  I haven't found a good way to eliminate this one yet, though.  I can extract the single line involved out to a method by itself and add @SuppressWarnings("unchecked") to that method, thus limiting the impact of having a block of code where I ignore warnings.  Any better options?  I don't want to turn these warnings off in Eclipse.  Before I came to the code, it was simpler, but still provoked warnings:  HashMap getItems(javax.servlet.http.HttpSession session) {   HashMap theHash = (HashMap)session.getAttribute("attributeKey");   return theHash; }   Problem was elsewhere when you tried to use the hash you'd get warnings:  HashMap items = getItems(session); items.put("this", "that");  Type safety: The method put(Object, Object) belongs to the raw type HashMap.  References to generic type HashMap&lt;K,V&gt; should be parameterized. A malevolent computer with AI takes over a woman's house with the intent of hybrid computer/human procreation. The evil computer seals off the house with the woman in it and keeps her prisoner while it prepares. I read the tale sometime in the late 80's or the early 90's. It was one of many of my missing books that got yardsaled by my in-laws when I wasn't looking. It may also have been made into a movie, but I didn't see the film. Question about Subrings and integraly closed Well, I already searched meta as well as cleared my browser cache.  I realize this may be a SO cache problem, but it still seems kind of strange to me.    The deleted question is (assuming it still exists).  Shouldn't deleted questions only be visible to 10k users?  I'm only at 2k. What amp rating of 24vac transformer for LM317T? I want to know what size transformer for LM317 at full 30 VDC. I know its a 24 VAC center tapped transformer but is 1 A or 5 A transformer best suited for a linear power supply of 1.5-30 VDC?  I will be using a standard LM317 variable power supply circuit with the 2200 uF 50 V smoothing and the 240 ohm drain resistor and potentiometer. I have a homemade oversized aluminum heat-sink that is quite large.