In middle school (ca. 1976) I read a science fiction book with a title similar to "Psi Phi."  Unfortunately, I wasn't familiar with the Greek alphabet at the time, so the title never made sense to me, so I can't recall it accurately. Based on my vague memory of the title, I'm thinking it may have been an anthology or a series of science fiction novelas.  The story was about a man who, while experimenting on "a block of tungsten," learned how to travel to a different universe at will.  He described the process of learning to travel there as "knowing where the latch on a secret drawer was."  While in the other universe, his surroundings were uninterpretable, "like swirling shapes and colors." He noticed his own body was (consistent with everything else in this universe) a confusing mass of swirling shapes and colors.  Eventually, a being from the other universe followed him back to his universe.  It was a woman with purple eyes.    That's about all I remember. Except that I enjoyed the story and read it 3 or 4 times.  One of the reasons I kept coming back to it, was that it did refer to a number of things (like different elements, such as tungsten) that I was just beginning to learn about.  I didn't understand all the connections the story made, but they intrigued me.  I'd like to read the story again as an adult.  Would anyone know the name of the book, the name of the story, or the author's name?
In the 1960s I read book--an older children's book, I think--which I loved, and still remember, roughly.  I have no idea what the title is or who the author is, and I'm wondering if anyone knows this one:  Scientists had invented a device which they didn't fully understand, and which had puzzling effects.  For example, when a pencil was put into the machine, it disappeared, and then reappeared inside out: The lead was on the outside.  When people went into the machine, they came back dead, having died from fright.  Finally they sent a very open-minded person into the machine.  She was an artist, I think.  She was able to return alive, and described an alternate universe in which geometry was very different.  I distinctly remember that there were supposedly square triangles or four-sided triangles--or was it three-sided squares?  (This is, of course, a literally contradictory claim, but I didn't see the matter as clearly then.)  Thanks!
In Fringe's season 1, the episode  (1x13) shows how  travels on VertusAir flight 718. We witness how he develops some strange symptoms, withdraws into a lavatory and transforms into a porcupine-like monster.  At the end of season 3, Peter "switches" the timeline (changing the past and making the present continue in a different timeline henceforth) from blue- to orange-verse. Various statements throughout the 4th season indicate time (the date) was not reset; Olivia and Walter have been working on Fringe cases for some three years etc. - hence it is safe to say that season 4 plays 3 years after season 1.  Then, in the episode  (4x16), the events from 1x13 happen again, up to the point of Bowman's transformation, which this time doesn't happen (not aboard the plane, anyway). As far as I can tell, great care was taken to exactly recreate the events from the season 1 episode, including hiring the same actors to play the flight attendants once again ( and ), so obviously this is supposed to be the same event with slight changes.  Peter, as well as Olivia - who is in the process of regaining her memories from the blue-verse -, remember the events from 1x13 and note the difference that Bowman's transformation happened later this time, implying that in the orange-verse, everything related to flight 718 played out the same way, except for the small difference that the transformation happened a bit later.  BUT ... all of this happened 3 years later!! Is there any explanation for this?  How unlikely is it that in the orange-verse timeline, Marshall Bowman is on the very same flight with the very same flight attendants 3 years after the same would have happened in the blue-verse? Mind you, this is not a "small change" in the course of events while mostly everything else stays the same.  So, why did Peter and Olivia realize the transformation happened a tad later in the orange-verse timeline, but were not baffled by the fact that essentially the same events as in the blue-verse happened, but three years later?  EDIT: Not only the flight and the flight attendants were the same in both episodes. The passenger next to Bowman was the same, an elderly lady played by  both times, as well. Moreover, the transcripts of  and  reveal that the dialogue between Bowman, the passenger next to him, and the cabin crew is the same down to the lines of text until the moment of transformation.  Interestingly, the announcement by the captain in the beginning seems to be different - starting the inflight movie + selling headsets vs. circling before beginning the final descent + selling snacks. On the other hand, this could be presumed to be a slight retcon, as in 4x16, it was crucial for the plot that the plane would be close to landing, and starting the inflight movie would not make much sense right before landing. How do you uninstall wine 1.5? Why is 4 not an instance of Number? Just curious:    4 instanceof Number => false new Number(4) instanceof Number => true?   Why is this? Same with strings:    'some string' instanceof String returns false new String('some string') instanceof String => true String('some string') instanceof String also returns false ('some string').toString instanceof String also returns false   For object, array or function types the instanceof operator works as expected. I just don't know how to understand this.  [new insights]  Object.prototype.is = function() {         var test = arguments.length ? [].slice.call(arguments) : null            ,self = this.constructor;         return test ? !!(test.filter(function(a){return a === self}).length)                : (this.constructor.name ||                   (String(self).match ( /^function\s*([^\s(]+)/im )                     || [0,'ANONYMOUS_CONSTRUCTOR']) [1] ); } // usage var Newclass = function(){};  // anonymous Constructor function var Some = function Some(){}; // named Constructor function (5).is();                     //=&gt; Number 'hello world'.is();           //=&gt; String (new Newclass()).is();        //=&gt; ANONYMOUS_CONSTRUCTOR (new Some()).is();            //=&gt; Some /[a-z]/.is();                 //=&gt; RegExp '5'.is(Number);               //=&gt; false '5'.is(String);               //=&gt; true Arithmetic and geometric sequences: where does their name come from? Where does the name of these two famous types of sequences come from?  The article  of Wikipedia says that the geometric sequence is called like this because every term is the geometric mean of its two adjacent terms. Though it is true, it only reduces the question to: why is the geometric mean geometric (in opposition to the arithmetic mean).   Continuing my investigation on , I was told that a square with the same area than a rectangle with sides $a$ and $b$ has their geometric mean $\sqrt{ab}$ for side. That's again totally true, but a square with same perimeter than this rectangle of sides $a$ and $b$ has their arithmetic mean $\frac{a+b}{2}$ for side!  Thus, my question: Who coined these names? And why? Why is the geometric mean more geometric than the arithmetic mean? Certificate error when using Citrix Receiver How do I iterate over the properties of an anonymous object in C#? Title page line spacing I have a simple problem but I didn't manage to find any answer for it. In my title page, I just used  \title{Name of the title}   then  \hrule height 0,1cm \leavevmode \\[0,5cm]     {\Huge{\textbf{\@title}}}\\[0,5cm] \hrule height 0,1cm \leavevmode \\[0,5cm]   to print the title of my document. But it takes more than 3 lines on the PDF file, and I have a different spacing between the 1st and 2nd line compared to the 2nd and 3rd, which is a bit frustrating.   Anyone got an idea of why ? A book on quantum mechanics supported by the high-level mathematics What is a Pythonic way to pad a numeric string with zeroes to the left, i.e. so the numeric string has a specific length? Are there any stats about the percentage of close reasons used to close questions   Successfully (preferably, based on the number of closed questions) Unsuccessfully (alternatively, the total percentags of close votes cast by users)   ?   Is there any way to get this from the query explorer? Can't delete files in trash because they don't exist on OS X 10.6? Something funky happened on one of my external drives and now whenever I plug it in 2 files show up in my Trash.  If I empty the Trash via Finder, nothing happens.  Ditto for the Option+Empty Trash method.  Listing them via Terminal shows them as there  $ sudo ls .Trashes/501 ¶_|íìê&lt;-.b?†            æâù©ìë—‡.*?§   But attempting to rm them or get any information about them shows them as not there  $ sudo ls -F .Trashes/501/ ls: ¶_|íìê&lt;-.b\032†: No such file or directory ls: æâù©ìë—‡.*\026§: No such file or directory  $ sudo rm .Trashes/501/* rm: .Trashes/501/¶_|íìê&lt;-.b\032†: No such file or directory rm: .Trashes/501/æâù©ìë—‡.*\026§: No such file or directory   Any thoughts?  I've never seen anything like this.  Thanks in advance! What's the 1 inch square knob sticking out of the wall? How many of Trelawney's prophecies have come true? Sometimes writing braces and omitting them produces the same result:  \tilde{\psi}  \mathrm{e}^{\mathrm{i} \pi}   vs  \tilde \psi   \mathrm e^{\mathrm i \pi}   Or (taken from Werner's comment below)   \frac{1}{2} vs \frac12   If that's the case, how bad for the quality of my code is omitting them? Of course, if one compiles a pair of formulas, there is no difference. But, since I ignore how TeX works, my point is: if one writes long codes with these habits,   doesn't TeX go somehow crazy because I'm not writing as it expects?   For instance, does it have any effect on how fast are long documents compiled? Any reason to keep them? What is ground and what does it do? Why does a find field value in one application show up in a the find field of another application? On my MacBook Pro I have found that several applications seem to share the value for a find.  For example, I searched 'applestackexchange' in Safari's unified address bar, then I switch to Xcode and click into a Find field.  The first word of my search in Safari then appears there.  iTerm2 and Sublime Text 2 also seem to participate in this sharing.  Running latest Mountain Lion on  a 2012 MBP. Undergraduate research field different from PhD field Solve $$\int \limits_{0}^{\infty} \frac{\cos(x)}{\cosh(x)} dx$$ without complex integration.  This integral can be very easily solved with contour integration, but how can you solve it without taking a tour in the complex plane? Locating stolen phone after factory reset I assume any reasonable thief will wipe the phone as soon as possible, thus removing any tracking apps and user accounts.  I there a method to track the phone any way?  A possible method is to use a tracking app (and it's configuration) that's embedded in a custom ROM. Let $G$ be a non-empty finite set with an associative binary operation so that cancellation law holds, i.e. $ab=ac$ or $ba=ca$ implies $b=c$, for any choices of $a,b,c$ in $G$. Assume that there is an identity element $e$ in $G$. Show that $G$ is a group.  Proof: To show $G$ is a group, conditions must hold. Suppose that $ab=ac$, then $b=eb=(a^{-1}a)b =a^{-1}(ab)=a^{-1}(ac) =(a^{-1}a)c=ec=c$. So left cancellation holds in $G$.  2) Suppose $ba=ca$, then $b=be=b(aa^{-1}) =(ba)a^{-1}=(ca)a^{-1} =c(aa^{-1})=ce=c$. So right cancellation holds in $G$.  3) If $a$ exists in $G$ then $aa^{-1}=a^{-1}a=e$, where $a$ is an inverse of $a^{-1}$. Since inverses are unique, $(a^{-1})^{-1}=a$.  4) Let $x$ be the inverse of $ab$. Then $(ab)x=e$. By associativity we have $a(bx)=aa^{-1}$. Through left cancellation we have  $bx=a^{-1}bx=ea^{-1}=b(b^{-1}a^{-1})$ and $x=b^{-1}a^{-1}$.  Thus $(ab)^{-1}=b^{-1}a^{-1}$. So all conditions hold, $G$ is a group.  Is this proof correct? I know to show $G$ is a group these conditions have to be met. This is all I have to show right?