explain xkcd - User contributions [en]

1125: Objects In Mirror

2012-10-26T00:37:43Z

Noodle: Australian vehicles do not have this warning. Its for US motorists.

{{comic
| number = 1125
| date = October 24, 2012
| title = Objects In Mirror
| image = objects in mirror.png
| imagesize =
| titletext = Universes in mirror, like those in windshield, are larger than they appear.
}}

==Explanation==
For all people who are not from USA, India, Canada and Korea: "Objects in mirror are closer than they appear" is a required, although ridiculous "safety warning", required to be engraved on passenger side mirrors of motor vehicles.

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 rear-view mirror would create an insignificant and unobservable redshift.

Edwin Hubble was an astronomer credited ({{w|Stigler's law of eponymy|amid some controversy}}) with "Hubble's Law," which states that a Doppler shift can be observed for objects in space moving with relative velocity to 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 was one of many evidences towards the {{w|Big Bang}} theory.

The title text may be a reference to comic [[1110: Click and Drag]]. Or maybe the title text references that we see the universe as it was in the past, when it was smaller than it is today.

==Transcript==
:[View of a car mirror that reads "Objects in mirror are bluer than they appear"]
:Caption: Edwin Hubble's car

{{comic discussion}}

556: Alternative Energy Revolution

2012-10-12T01:37:19Z

Noodle: /* Explanation */

{{comic
| number = 556
| date = March 16, 2009
| title = Alternative Energy Revolution
| image = alternative_energy_revolution.jpg
| imagesize =
| titletext = The moment their arms spun freely in our air, they were doomed -- for Man has earned his right to hold this planet against all comers, by virtue of occasionally producing someone totally batshit insane.
}}

==Explanation==

Megan and cueball are looking at modern windmills harnessing wind energy into electrical energy. They comment that there's something creepy about the windmills.They allude to the "War of the Worlds" - most likely a reference to the Jeff Wayne rock version of {{w|Jeff Wayne's Musical Version of The War of the Worlds|War of the Worlds}}, which has paintings of the martian tripods somewhat like these windmills, and also "The Tripods" from John Christopher's {{w|The Tripods|tripods trilogy}} a children's series of books about aliens who ride in walking tripods.

Suddenly the windmills pylons split into three legs, becoming the tripods suggested.

In the final frame, {{w|Don Quixote}}'s horse largely resembles {{w|Don Quixote (Picasso)|the drawing}} by {{w|Pablo Picasso}}. In the original story of Don Quixote, he fights windmills, hence he is the appropriate person to deal with this threat - he is also "batshit insane".

There is a fan created [https://www.youtube.com/watch?v=kRuqPKcxMZY animation of this comic.]

==Transcript==
:[A field of windmills is silhouetted against dusk sky.]

:[Man and woman are standing and sitting on the ground overlooking the windmills.]
:Man: I'm all for green energy, but those turbines creep me out. They remind me of War of the Worlds, or the Tripod books.

:Woman: They -are- unnerving.
:Man: I can't shake the feeling that at any moment they'll—
:<<RUMBLE>>

:[A leg begins to split off one windmill.]
:<<crack>>

:[The leg separates from the body of the windmill.]

:[The new leg lands on the ground.]
:<<BOOM>>

:[Another leg begins to split off the other side of the windmill's body.]
:<<crack>>

:[The new leg hits the ground, forming a tripod base.]
:<<BOOM>>

:[Smoke rises from destroyed buildings as the windmills rampage across the field.]

:[Man and woman are now standing.]
:Woman: Oh no.
:Man: Al Gore, you've doomed us all.
:Woman: It's coming this way!
:Man: Run!

:[One of the enormous tripod windmill feet lands right behind the running couple, sending debris flying.]
:<<BOOM>>

:[Man and woman run.]
:Woman: What now?
:Man: Someone has to stop them.
:Woman: But who could--
:Voice from next panel: Stand aside!

:[Don Quixote sits mounted at the top of a hill, lance at the ready.]

{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Comics with color]]
[[Category:Windmills]]

556: Alternative Energy Revolution

2012-10-12T01:30:47Z

Noodle:

{{comic
| number = 556
| date = March 16, 2009
| title = Alternative Energy Revolution
| image = alternative_energy_revolution.jpg
| imagesize =
| titletext = The moment their arms spun freely in our air, they were doomed -- for Man has earned his right to hold this planet against all comers, by virtue of occasionally producing someone totally batshit insane.
}}

==Explanation==

Megan and cueball are looking at modern windmills harnessing wind energy into electrical energy. They comment that there's something creepy about the windmills.They allude to the tripods in War of the worlds - most likely a reference to the Jeff Wayne rock version of {{w|Jeff Wayne's Musical Version of The War of the Worlds|War of the Worlds}}, which has paintings of the martian tripods somewhat like these windmills, and also "The Tripods" from John Christopher's {{w|The Tripods|tripods trilogy}} a children's series of books about aliens who ride in walking tripods. Suddenly the windmills pylons split into three legs, becoming the tripods suggested.

In the final frame, {{w|Don Quixote}}'s horse largely resembles {{w|Don Quixote (Picasso)|the drawing}} by {{w|Pablo Picasso}}. In the original story of Don Quixote, he fights windmills, hence he is the appropriate person to deal with this threat.

There is a fan created [https://www.youtube.com/watch?v=kRuqPKcxMZY animation of this comic.]

==Transcript==
:[A field of windmills is silhouetted against dusk sky.]

:[Man and woman are standing and sitting on the ground overlooking the windmills.]
:Man: I'm all for green energy, but those turbines creep me out. They remind me of War of the Worlds, or the Tripod books.

:Woman: They -are- unnerving.
:Man: I can't shake the feeling that at any moment they'll—
:<<RUMBLE>>

:[A leg begins to split off one windmill.]
:<<crack>>

:[The leg separates from the body of the windmill.]

:[The new leg lands on the ground.]
:<<BOOM>>

:[Another leg begins to split off the other side of the windmill's body.]
:<<crack>>

:[The new leg hits the ground, forming a tripod base.]
:<<BOOM>>

:[Smoke rises from destroyed buildings as the windmills rampage across the field.]

:[Man and woman are now standing.]
:Woman: Oh no.
:Man: Al Gore, you've doomed us all.
:Woman: It's coming this way!
:Man: Run!

:[One of the enormous tripod windmill feet lands right behind the running couple, sending debris flying.]
:<<BOOM>>

:[Man and woman run.]
:Woman: What now?
:Man: Someone has to stop them.
:Woman: But who could--
:Voice from next panel: Stand aside!

:[Don Quixote sits mounted at the top of a hill, lance at the ready.]

{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Comics with color]]
[[Category:Windmills]]

555: Two Mirrors

2012-10-05T00:20:02Z

Noodle:

{{comic
| number = 555
| date = March 13, 2009
| title = Two Mirrors
| image = two_mirrors.png
| imagesize =
| titletext = If you actually do this, what really happens is Douglas Hofstadter appears and talks to you for eight hours about strange loops.
}}

==Explanation==
{{w|Bloody Mary (folklore)|Bloody Mary}} (folk lore), is a legendary ghost or spirit conjured to reveal the future. She is said to appear in a mirror when her name is called multiple times. The Bloody Mary apparition may be benign or malevolent, depending on historic variations of the legend. The Bloody Mary appearances are mostly "witnessed" in teenage group participation games, often as part of a game of truth or dare.

In this XKCD comic, Megan sets up two mirrors facing each other, in which she can see herself receding ad infinitum. She then says "Mirror Mirror" as in the folklore before ducking, conjuring an infinite number of malevolent spirits who jump from the mirror towards each other. Its not clear if they simply collide, or pass into the opposing mirror.

Douglas Hofstadter is the author of {{w|Gödel, Escher, Bach}} and {{w|I Am a Strange Loop}}. In the latter book he focuses on he idea of minds being self-referential. "In the end, we are self-perceiving, self-inventing, locked-in mirages that are little miracles of self-reference". This blends with the idea of the images of the person looking in the mirror being reflected endlessly.

==Transcript==
:[A girl sets up a full mirror adjacent to a bathroom-counter mirror]
:[The girl looks through the bathroom-counter mirror to see the infinite reflections]
:Girl: Bloody Mary, Bloody Mary, Bloody Mary.
:<<RAAGHHHHH>>
:[Girl ducks as the infinite Bloody Marys pop out between the two mirrors above her head]

{{comic discussion}}

555: Two Mirrors

2012-10-05T00:19:31Z

Noodle:

{{comic
| number = 555
| date = March 13, 2009
| title = Two Mirrors
| image = two_mirrors.png
| imagesize =
| titletext = If you actually do this, what really happens is Douglas Hofstadter appears and talks to you for eight hours about strange loops.
}}

==Explanation==
{{w|Bloody Mary (folklore)|Bloody Mary}} (folk lore), is a legendary ghost or spirit conjured to reveal the future. She is said to appear in a mirror when her name is called multiple times. The Bloody Mary apparition may be benign or malevolent, depending on historic variations of the legend. The Bloody Mary appearances are mostly "witnessed" in teenage group participation games, often as part of a game of truth or dare.

In this XKCD comic, Megan sets up two mirrors facing each other, in which she can see herself receding ad infinitum. She then says "Mirror Mirror" as in the folklore before ducking, conjuring an infinite number of malevolent spirits who jump from the mirror towards each other. Its not clear if they simply collide, or pass into the opposing mirror.

Douglas Hofstadter is the author of {w|Gödel, Escher, Bach} and {w|I Am a Strange Loop}. In the latter book he focuses on he idea of minds being self-referential. "In the end, we are self-perceiving, self-inventing, locked-in mirages that are little miracles of self-reference". This blends with the idea of the images of the person looking in the mirror being reflected endlessly.

==Transcript==
:[A girl sets up a full mirror adjacent to a bathroom-counter mirror]
:[The girl looks through the bathroom-counter mirror to see the infinite reflections]
:Girl: Bloody Mary, Bloody Mary, Bloody Mary.
:<<RAAGHHHHH>>
:[Girl ducks as the infinite Bloody Marys pop out between the two mirrors above her head]

{{comic discussion}}

555: Two Mirrors

2012-10-05T00:14:33Z

Noodle:

{{comic
| number = 555
| date = March 13, 2009
| title = Two Mirrors
| image = two_mirrors.png
| imagesize =
| titletext = If you actually do this, what really happens is Douglas Hofstadter appears and talks to you for eight hours about strange loops.
}}

==Explanation==
{{w|Bloody Mary (folklore)|Bloody Mary}} (folk lore), is a legendary ghost or spirit conjured to reveal the future. She is said to appear in a mirror when her name is called multiple times. The Bloody Mary apparition may be benign or malevolent, depending on historic variations of the legend. The Bloody Mary appearances are mostly "witnessed" in teenage group participation games, often as part of a game of truth or dare.

In this XKCD comic, Megan sets up two mirrors facing each other, in which she can see herself receding ad infinitum. SHe then says "Mirror Mirror" as in the folklore before ducking, conjuring an infinite number of malevolent spirits who jump from the mirror towards each other. Its not clear if they simply collide, or pass into the opposing mirror.

==Transcript==
:[A girl sets up a full mirror adjacent to a bathroom-counter mirror]
:[The girl looks through the bathroom-counter mirror to see the infinite reflections]
:Girl: Bloody Mary, Bloody Mary, Bloody Mary.
:<<RAAGHHHHH>>
:[Girl ducks as the infinite Bloody Marys pop out between the two mirrors above her head]

{{comic discussion}}

555: Two Mirrors

2012-10-05T00:12:45Z

Noodle:

{{comic
| number = 555
| date = 2009-3-13
| title = Two Mirrors
| image = two_mirrors.png
| imagesize =
| titletext = If you actually do this, what really happens is Douglas Hofstadter appears and talks to you for eight hours about strange loops.
}}

==Explanation==
{{w|Bloody Mary (folklore)}} , is a legendary ghost or spirit conjured to reveal the future. She is said to appear in a mirror when her name is called multiple times. The Bloody Mary apparition may be benign or malevolent, depending on historic variations of the legend. The Bloody Mary appearances are mostly "witnessed" in teenage group participation games, often as part of a game of truth or dare.

In this XKCD comic, Megan sets up two mirrors facing each other, in which she can see herself receding ad infinitum. SHe then says "Mirror Mirror" as in the folklore before ducking, conjuring an infinite number of malevolent spirits who jump from the mirror towards each other. Its not clear if they simply collide, or pass into the opposing mirror.

==Transcript==
:[A girl sets up a full mirror adjacent to a bathroom-counter mirror]
:[The girl looks through the bathroom-counter mirror to see the infinite reflections]
:Girl: Bloody Mary, Bloody Mary, Bloody Mary.
:<<RAAGHHHHH>>
:[Girl ducks as the infinite Bloody Marys pop out between the two mirrors above her head]

{{comic discussion}}