Trying to find this book. In it, over eons of time, a sun actually begins to think. He becomes self-aware, and then, one day MOVES itself, and its system.   I read this approximately 10-15 years ago, in paperback format, I believe.  Any help is appreciated!
One of whom destroys the Earth, perhaps accidentally, while fighting another... the plot also involves a human colony ship or planet that loses contact with the Earth; I think a small boy is also involved with the plot, although it's been 20-30 years since I read this story.  Any help would be appreciated!  It's driving my brother and me a bit batty.  Here's the batty brother's take: the main being has created others who are now at war, exploding stars. To escape, the main being accelerates the star of the human colony as a decoy. However, most of the story centers on some guy who winds up living forever, as they keep sticking him in cryogenic sleep and reawakening him. If memory serves me right, they abandon the colony planet for a while and move to asteroids as the star is weakening because it is using it's energy to accelerate. When it decelerates, it is the only star left in the universe. The one "being" was almost reduced to living off the energy of a black hole when it appears, and he sees it and sets off to go there, with a cryptic ending that the humans very well might fight him off.
How do I unload (reload) a Python module? I have a long-running Python server and would like to be able to upgrade a service without restarting the server. What's the best way do do this?  if foo.py has changed:     unimport foo  &lt;-- How do I do this?     import foo     myfoo = foo.Foo() $\sum a_n$ be convergent but not absolutely convergent, $\sum_{n=1}^{\infty} a_n=0$ Let $\sum a_n$ be convergent but not absolutely convergent, $\sum_{n=1}^{\infty} a_n=0$,$s_k$ denotes the partial sum then could anyone tell me which of the following is/are correct?  $1.$ $s_k=0$ for infinitely many $k$  $2$. $s_k&gt;0$ and $&lt;0$ for infnitely many $k$  3.$s_k&gt;0$ for all $k$  4.$s_k&gt;0$ for all but finitely many $k$  if we take $a_n=(-1)^n{1\over n}$ then $\sum a_n$ is convergent but not absolutely convergent,but I don't know $\sum_{n=1}^{\infty} a_n=0$? so I am puzzled could any one tell me how to proceed? Horizontal enumeration in multiple columns Consider the following minimal example:  \documentclass{article}  \setlength{\parindent}{0mm}  \usepackage{paralist} \usepackage{tabto}  \begin{document}  \NumTabs{3} \begin{inparaenum} \item text \tab\item text \tab\item text \tab\item text \tab\item text \tab\item text    \end{inparaenum}  \end{document}   Which results in:    It does exactly what I want, but I was wondering whether it was possible to create an environment, say tabbedEnum so that we can eliminate the use of the \tab, in particular, that the first case doesn't need a tab but all others do. Something of the form:   \begin{tabbedEnum}[3] \item text \item text \item text \item text \item text \item text \end{tabbedEnum} How can I add a new user as sudoer using the command line? After I add a user using adduser, I can't see it via System > Administration > Users and Groups unless I log out and then log in again. Is that normal?  Also, can I set a newly added user as a sudoer or do I have to change that only after adding it? How can I do that via the shell?  Finally, can I delete the original user that was created upon initial installation of Ubuntu, or is this user somehow 'special'? I have installed the pimd service by means of apt. This comes with an upstream systemd unit file (/lib/systemd/system/pimd.service).  I want the service to be restarted when for some reason it gets killed, hence I wish to add the line Restart = always in the unit file.   However, I don’t want to modify the upstream unit file.  Is there any workaround for this? It would be nice to  for .  As it is, SE kind of stands out (in a not cool way): Deriving Heaviside-Feynman formula for the electric field of an arbitrarily moving charge from Lienard-Wiechert potential Easiest way to add a text to the beginning of another text file in Command Line (Windows) What is the easiest way to add a text to the beginning of another text file in Command Line (Windows)? Question about Subrings and integraly closed Can a goalkeeper chip the ball to the head of a teammate from a goal kick to circumvent the backpass restriction? How to prove $\det(I+uv^\intercal)=1+v^\intercal u$ Let be $u,v\in\mathbb{R}^n$, then $\det(I+uv^\intercal)=1+v^\intercal u $ where $I$ denotes the identity matrix of order $n$. How to prove this?   what I did:   let be $A=\{n\in\mathbb{N}: \forall u,v \in \mathbb{R^n}, \det(I+uv^\intercal)\neq1+v^\intercal u  \} $, and suppose $A\neq \varnothing $, then for the well-orderer-principle there exists $n_0\in A$ such $n_0\leq n,\;\forall n\in A$. since $1\notin A,\; n_0\neq 1 \rightarrow n_0-1\in\mathbb{N}\setminus A  $ so: $$\forall u,v\in\mathbb{R^{n_0-1}}: \det(I+uv^\intercal)=1+v^\intercal u $$ Then, let be $u,v\in\mathbb{R}^{n_0}$, so $$\det(I+uv^\intercal)= \displaystyle\sum_{j=1}^{n_0}(-)^{1+j}a_{1j}\det(A_{1j})$$ where $a_{ij}=\begin{cases} u_iv_j+1 &amp; i=j \\ u_iv_j &amp; i\neq j \end{cases}$, and $A_{1j}$ is the  submatrix of $I+uv^\intercal$ that results deleting the i-file and j-column. Then I try to open the term for $j=1$ and try to use the relation for the new matrix of $n_0-1$ order with the determinant because it holds the same form but I have other terms which difficult me the work. Do you know other method?.  Ps. , in page 2 I've found something similar but I don't understand what it means PS. I'm taking a course of numerical analisys Is there a clever solution to Arnold's "merchant problem"? There is a problem that appears in . The problem is also quoted .  You take a spoon of wine from a barrel of wine, and you put it into your cup of tea. Then you return a spoon of the (nonuniform!) mixture of tea from your cup to the barrel. Now you have some foreign substance (wine) in the cup and some foreign substance (tea) in the barrel. Which is larger: the quantity of wine in the cup or the quantity of tea in the barrel at the end of your manipulations?  Here's my solution: The key is to consider the proportions of wine and tea in the second spoonful (that is, the spoonful of the nonuniform mixture that is transported from the cup to the barrel). Let $s$ be the volume of a spoonful and $c$ be the volume of a cup. The quantity of wine in this second spoonful is $\frac{s}{s+c}\cdot s$ and the quantity of tea in this spoonful is $\frac{c}{s+c}\cdot s$. Then the quantity of wine left in the cup is $$s-\frac{s^2}{s+c}=\frac{sc}{s+c}$$ and the quantity of tea in the barrel now is also $\frac{cs}{s+c}.$ So the quantities that we are asked to compare are the same. However, Arnol'd also says  Children five to six years old like them very much and are able to solve them, but they may be too difficult for university graduates, who are spoiled by formal mathematical training.  Given the simple nature of the solution, I'm going to guess that there is a trick to it. How would a six year old solve this problem? My university education is interfering with my thinking. Can I convert flat bar to drop bars on a hybrid bike Using the definition of Riemann integrability, prove that $f $is Riemann integrable on $[0,1]$ The following problem came up on a test, and I didn't get it correctly. Please help me understand the problem.  Problem: Define $f:[0,1] \to \mathbb{R}$ by $$     f(x)=  \begin{cases}     1,&amp; \text{if } x=\frac{1}{n}\\     0              &amp; \text{otherwise} \end{cases} $$ for some integer n.  Using the definition of Riemann integrability, prove that f is Riemann integrable on $[0,1]$ and evaluate the Riemann integral $\int_{0}^{1} f(x)dx$.  My Solution:  Let $\epsilon&gt;0$ and $P$ be the partition of $[0,1]$ such that $P=\{0,\frac{1}{n}- \frac{\epsilon}{3},\frac{1}{n}+ \frac{\epsilon}{3},1\}$.Then note that   $U(f,P)=M_0\Delta x_0 +M_1\Delta x_1+M_2\Delta x_2=0+(\frac{1}{n}+ \frac{\epsilon}{3})-(\frac{1}{n}+ \frac{\epsilon}{3})+0=\frac{2\epsilon}{3}$ and   $L(f,P)=0$.   Thus, for every $\epsilon&gt;0$ $$U(f,P)-L(f,P)=\frac{2\epsilon}{3}&lt;\epsilon$$.  This is the prove that I gave and the mistake that I made was that I fixed n. Some important things that I noticed about this problem were that if you graph the function $f(x)$ most of the points fall to the left or close to zero and a fewer fall to the right. Hence, this makes me believe that I need a partition such that I capture most of the points near zero so that I am only left with a finite number of points close to 1. However, I can't seem to find this partition.Any help would be appreciated. In particular, I would like to know how you come up with the partition since I always struggle to come up with one. Thank you! Should I buy a Canon 55-250mm lens or 70-300mm for my Rebel T3i? I have the basic 18-55mm lens that came with my camera but I need a next step up that's not too expensive.   What are the most common types of photos shot with either lenses? Or what is each lens best for? Finding $\int_0^{\infty}xe^{-\lambda x} \, dx$ How to integrate:  $$\int_0^\infty x \, \lambda e^{-\lambda x} \, dx$$    I tried using integration by parts:  Let $u = x$ and $dv = \lambda e^{-\lambda x} \, dx$  Then $du = dx$  And $v = - \lambda e ^{-\lambda x}$  Correct so far?   Then   $$\begin{aligned} uv - \int v \, du &amp;= -\lambda x e^{-\lambda x} - \int (- \lambda e^{- \lambda x}) dx \\ &amp;= -\lambda x e^{-\lambda x} - \lambda e^{-\lambda x} \end{aligned}$$    The correct answer from lecture notes      UPDATE 2  Let $u=\lambda x$ and $dv = e^{-\lambda x} dx$  Then $du = \lambda \, dx$  $$dv = e^{-\lambda x} \, dx$$  Let $y = -\lambda x$  Then $dy = -\lambda \, dx$  So $dx = -\frac{1}{\lambda} dy$  $$\begin{aligned} v &amp;= \int e^u \cdot - \frac{1}{\lambda} du \\ &amp;= - \frac{1}{\lambda} e^{-\lambda x} \end{aligned}$$  But here I seem to have an extra $- \frac{1}{\lambda}$ in $v$?  If I continue using integration by parts, I get:   $$-x e^{-\lambda x} + \color{red}{\frac{1}{\lambda}} \int e^{-\lambda x} \, dx$$ There was a foolish (in my opinion) question asked on Scifi.SE       James bond keeps returning with a different face, albeit usually a similar one, and often operates with high-tech gadgetry that seem to be on par with the Doctor's sonic screw driver.   In my opinion each new actor represents a reboot of the franchise using the new face, not a continuation of the story.   Is there any continuity between versions of James Bond which change actors? I'm not talking about characters like M or Q, I'm talking about events or past advisories being referenced in a different Bond movie where the main actor was someone else. Differences between astronomy, astrophysics and cosmology? cron job schedule I took this photo of the blood moon this morning and I am finding many of my photos, especially landscape photos, have a significant lack of clarity. I'm not looking for a photo critique because I know this particular photo is crap. I'm looking to identify my source of failure to nail a significantly clear photo.     Setup  Canon EOS 70D with a 100-300 telephoto lens (I'm sorry I don't know the exact model. It's from Canon but not one of their professional quality lenses.)   Aperture: f/5.6 Shutter: 1 sec. ISO: 1000 Focal Length: 300mm Metering mode: Spot White Balance: I manually set the WB to 5500 kelvin, it looked fine in live view. Focus Mode: Manual Drive: 2 sec timer delay   Mounted on a decently stable tripod  Process  I turn on live view, and square up the target in the display. I then set my focal length, focus in using live view, adjust the focus as sharp as possible and take the pic. I've noticed that in this case, the picture was incredibly grainy, which doesn't translate to the final photo, but wonder if it has anything to do with it.  This particular shoot I found it difficult to balance out the variables with a dark sky and a moving moon that starts blurring after 1-2 seconds of exposure, which is why I had the aperture wide open and the ISO cranked up.  I can't tell where I'm failing:  Equipment:  The 70d takes great photos but the telephoto is not great when it's totally zoomed in. My wallet doesn't hold enough cash for a motorized mount to track objects in the sky.  Circumstance: I've seen great photos of the moon with the use of a camera and a tripod, so I know this is possible. Although, I keep seeing pictures of this big gorgeous moon over the landscape, and when I use my wide-angle, the moon shows up as a dot. What the hell are people doing to get the moon so big?  Beginner skill level: I know this is the biggest culprit, but being the beginner, I'm unable to know where to adjust.