Editing 679: Christmas Plans

Jump to: navigation, search

Warning: You are not logged in. Your IP address will be publicly visible if you make any edits. If you log in or create an account, your edits will be attributed to your username, along with other benefits.

The edit can be undone. Please check the comparison below to verify that this is what you want to do, and then save the changes below to finish undoing the edit.
Latest revision Your text
Line 8: Line 8:
  
 
==Explanation==
 
==Explanation==
−
This comic centers around a joke about {{w|Quantum superposition}} in physics - if you don't observe something, it has all possible states, not a specific one. It is a double-entendre with the word ''observe'' meaning both "look at" (physics sense) and "celebrate" (a holiday). One of the most famous examples on this is the {{w|Schrödinger's cat}} paradox.
+
This comic centers around a joke about {{w|Quantum Entanglement}} in physics - if you don't observe something, it has all possible states, not a specific one. It is a double-entendre with the word ''observe'' meaning both "look at" (physics sense) and "celebrate" (a holiday). One of the most famous examples on this is the {{w|Schrödinger's cat}} paradox.
  
 
In this comic, a Jewish physicist does not know when Christmas is. Being a physicist, he believes that since he doesn't observe Christmas, it therefore has no definite date.
 
In this comic, a Jewish physicist does not know when Christmas is. Being a physicist, he believes that since he doesn't observe Christmas, it therefore has no definite date.
  
−
Adding to the joke, the physicist's observation is actually valid for certain other holidays (such as Easter) that don't have a definite (i.e. annual) date. Because Easter's date seemingly bounces around at random, it could be said to exist in a superposition of all possible Easter dates, and as he doesn't observe (celebrate) Easter, the physicist would be unlikely to check which date it falls this year. Thus, he would be unsure of when the holiday is celebrated. 
+
The title text refers to another principle in physics where the act of measuring something must also change it in some way.  If one drops a thermometer into into a mug of water, energy spent (or released) when heating (or cooling) the mercury in the thermometer changes the temperature of the water in the mug by a small amount.  The only way not to interfere with the temperature of the water in the mug is not to measure it.
−
 
 
−
The title text refers to another principle in physics where the act of measuring something must also change it in some way.  If one drops a thermometer into a mug of water, energy spent (or released) when heating (or cooling) the mercury in the thermometer changes the temperature of the water in the mug by a small amount.  The only way not to interfere with the temperature of the water in the mug is not to measure it.
 
  
 
==Transcript==
 
==Transcript==
Line 37: Line 35:
 
[[Category:Christmas]]
 
[[Category:Christmas]]
 
[[Category:Puns]]
 
[[Category:Puns]]
−
[[Category:Multiple Cueballs]]
 

Please note that all contributions to explain xkcd may be edited, altered, or removed by other contributors. If you do not want your writing to be edited mercilessly, then do not submit it here.
You are also promising us that you wrote this yourself, or copied it from a public domain or similar free resource (see explain xkcd:Copyrights for details). Do not submit copyrighted work without permission!

To protect the wiki against automated edit spam, we kindly ask you to solve the following CAPTCHA:

Cancel | Editing help (opens in new window)

Templates used on this page:

Retrieved from "https://www.explainxkcd.com/wiki/index.php/679:_Christmas_Plans"