What's the best GR book for recreational study?
Books for general relativity
Unupvote immediately followed by an upvote gives me a net -10 reputation points (This is on NT based Windows like 2000, XP, Vista, 7)  On the command-line, the percentage characters are ignored:  wget "http://www.justitie.nl/images/Handleiding%20voor%20verwerkers%20persoonsgegevens_tcm34-3940.pdf"   So it correctly downloads this file (each %20 becomes a space):  "http://www.justitie.nl/images/Handleiding voor verwerkers persoonsgegevens_tcm34-3940.pdf"   But inside a batchfile, all the %20 are being interpreted as expanding parameter 2 (which is empty) resulting in this file to get downloaded (each %20 becomes 0):  "http://www.justitie.nl/images/Handleiding0voor0verwerkers0persoonsgegevens_tcm34-3940.pdf"   Is there a way to circumvent the percentage parameter expansion?  --jeroen Software to read a QR code? I saw a  reading a book, but I don't have a smart phone to check it.    So I just took a picture of it and saved my PC. And I downloaded libdecoderqr0, libdecodeqr-dev, libdecodeqr-examples for reading it. But I don't know how to use it.    What do I do next, or is there a nicer way to read QR codes? Software center disappeared [19.10] I have had trouble with sound (now fixed) since upgrading to 19.10, and in the middle of trying the common solutions, the Software Center "disappeared". I got aware of quite late, so I don't know what caused it.  Anyway, would you know how to reinstall it ? Trying sudo apt-get install software-center doesn't work. I use the scroll function with my mouse and it works fine. But either in script, or in terminal sections of Spyder, I can't use the touchpad for scrolling. I do not experience any problems with my touchpad in other programs like Word, Chrome etc. Is there any option for this in Spyder, specific for touchpad?  I am using Lenovo Legion Y520, Windows 10. Adjective meaning "argumentative for argument's sake"? maximum subarray of an array with integers Extra Backslash Required in First Appended Newline in sed Quantum computers are known to be able to crack  a broad range of cryptographic algorithms which were previously thought to be solvable only by resources increasing exponentially with the bit size of the key. An example for that is .  But, as far I know, not all problems fall into this category. On , we can read     Researchers have developed a computer algorithm that doesn’t solve problems but instead creates them for the purpose of evaluating quantum computers.   Can we still expect a new cryptographic algorithm which will be hard to crack using even a quantum computer? For clarity: the question refers to specifically to the design of new algorithms. "every" vs "each"? How to prevent ENTER keypress to submit a web form? How to avoid returning a Null if there is no "else" condition in an If construct New UI encourages askers to confirm or dispute duplicate votes Can someone please explain how I can install  in the following ways?   By using the package manager? By downloading and installing a pre-built package? When/Why Did Love Escape Voldemort? We know that Voldemort does not love. He does not understand it, nor (generally) the magic that it possesses. He knows  of the sort.  [...] &quot;you possess in such quantities and which Voldemort has not at all.&quot; [...] &quot;because he could not bear to reside in a body so full of the force he detests. In the end, it mattered not that you could not close your mind. It was your heart that saved you.&quot; (Harry Potter and the Order of the Phoenix, page 1075)  The above confirms it (although I believe there is a better quote), though  reinforces it. The fact that he hugs so awkwardly shows that he does not really know how, due to his lack of love. I realize that Voldemort's appearance started to change after he started to create Horcruxes, but surely he had an ounce of love when he was a child? The hugging scene perhaps shows that he never once loved his whole life (possibly due to the love potion with his parents?). If so, when did Voldemort begin to have no love at all, and why? What determines how much experience I get from a hearthstone match in play mode? Sometimes I win handily and get a little experience, sometimes I squeak out a victory and get a lot.  How is experience earned? net use command works in command prompt, but not in bat file A word used to describe someone who loves to be photographed In my  I was printing a double using cout that got rounded when I wasn't expecting it.  How can I make cout print a double using full precision? Future Simple and Future Perfect I've read  about Future Simple and Future Perfect, but I still can't understand the exact usage of these two tenses. Is there any diffrence between the following?     I will do my homework by 6 p.m.   I will have done my homework by 6 p.m.       I will do my homework after school   I will have done my homework after school   Also, I've checked the word 'by' in  and there're some confusing examples:       By the time (that) this letter reaches you I will have left the country.   Can I use 'By the time (that) this letter reaches you I will leave the country' instead?