https://www.explainxkcd.com/wiki/api.php?action=feedcontributions&feedformat=atom&user=46.126.181.133 2026-06-24T18:09:26Z User contributions MediaWiki 1.30.0 https://www.explainxkcd.com/wiki/index.php?title=10:_Pi_Equals&diff=24851 2013-01-07T08:59:46Z

<p>46.126.181.133: /* Explanation */</p> <hr /> <div>{{comic<br /> | number = 10<br /> | date = September 30, 2005<br /> | title = Pi Equals<br /> | image = pi.jpg<br /> | titletext = My most famous drawing, and one of the first I did for the site<br /> }}<br /> <br /> ==Explanation==<br /> [http://www.angio.net/pi/whynotpi.html Probability of Finding Strings In Pi]<br /> <br /> There are two possible references here. One is from the book ''{{w|Contact (novel)|Contact}}'' by Carl Sagan, where the existence of God was shown in the last chapter to be encoded in the digits of {{w|pi}}. The other is an old joke of a {{w|fortune cookie}} with a fortune that reads &quot;Help! I'm trapped in a fortune cookie factory!&quot; or it's reference of the Mac OS 6 and 7 [http://www.mackido.com/EasterEggs/BlueMeanies.html &quot;BlueMeanies&quot; easter egg] &quot;Help! Help! We're being held prisoner in a system software factory!&quot;.<br /> <br /> ==Trivia==<br /> *The book version of this comic (in ''[http://store.xkcd.com/products/xkcd-volume-0 xkcd: volume 0]'') has different title text from the online original: ''&quot;I've put rescue instructions in e. You'll need the cheat codes for your universe, which I hid in the square root of two.&quot;''<br /> *This is the eleventh comic originally posted to livejournal. The previous was [[9: Serenity is coming out tomorrow]]. The next was [[14: Copyright]].<br /> <br /> ==Transcript==<br /> :Pi = 3.141592653589793helpimtrappedinauniversefactory7108914...<br /> <br /> {{comic discussion}}<br /> <br /> [[Category:Comics posted on livejournal]]<br /> [[Category:Math]]</div>

46.126.181.133 https://www.explainxkcd.com/wiki/index.php?title=1125:_Objects_In_Mirror&diff=17467 2012-11-19T16:00:47Z

<p>46.126.181.133: /* Explanation */</p> <hr /> <div>{{comic<br /> | number = 1125<br /> | date = October 24, 2012<br /> | title = Objects In Mirror<br /> | image = objects in mirror.png<br /> | imagesize = <br /> | titletext = Universes in mirror, like those in windshield, are larger than they appear.<br /> }}<br /> <br /> ==Explanation==<br /> For all people who are not from USA, India, Canada and Korea: &quot;Objects in mirror are closer than they appear&quot; is a required, although marginally ridiculous &quot;safety warning&quot;, required to be engraved on passenger side mirrors of motor vehicles. These mirrors in these countries are typically the only ones that are slightly convex, making objects appear smaller (and farther away) than their true size. Other countries often have convexity in diver-side and passenger-side rearview mirrors to give a larger field of view, at the cost of natural distance proportions of the mirror image, without making any statements about it on the mirror itself using engravings. <br /> <br /> This comic is a reference to the phenomena known as {{w|redshift}}/{{w|blueshift}}. Due to the {{w|Doppler effect}}, objects that are moving toward an observer appear bluer than they actually are (known as blueshift). Objects moving away from the observer (e.g. objects viewed in the rear-view mirror of a moving vehicle) appear redder than they actually are (known as redshift), and thus the objects are in reality bluer than they appear. This is generally relevant only in terms of high speed motion such as observation of the expansion of the universe in astrophysics. The joke is that the relative speed of any object visible in a side-view mirror would create an insignificant and unobservable redshift.<br /> <br /> Edwin Hubble was an astronomer credited ({{w|Stigler's law of eponymy|amid some controversy}}) with &quot;{{w|Hubble's Law}},&quot; which states that a Doppler shift can be observed for objects in deep space moving with relative velocity to Earth and that their velocity is proportional to their distance from Earth. Probably the most famous application of the law was measurement of relative velocities of galaxies, such as those seen in the picture known as {{w|Hubble Deep Field}}, taken by the {{w|Hubble Space Telescope}}. The results proved that most galaxies keep getting farther apart as a result of expansion of the universe. This is one of many pieces evidence supporting the {{w|Big Bang}} theory.<br /> <br /> The title text references that we see the universe as it was in the past(due to the distances involved and the speed of light), when it was smaller than it is today. It may may also be a reference to comic [[1110: Click and Drag]].<br /> <br /> ==Transcript==<br /> :[View of a car mirror that reads &quot;Objects in mirror are bluer than they appear&quot;]<br /> :Caption: Edwin Hubble's car<br /> <br /> {{comic discussion}}</div>

46.126.181.133