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==Explanation==
 
==Explanation==
The comic is inspired by the now disproven {{w|BICEP2}} discovery of {{w|gravitational waves}} from the early universe, hence providing evidence for the {{w|Inflation_(cosmology)|cosmic inflation}} hypothesis. [[Megan]] is excited about this and tells [[Ponytail]] all about it. She is impressed by the fact that these waves were created when the universe was extremely small and the expanding universe has "imprinted" the gravity waves. (See also [[1642: Gravitational Waves]]).
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{{incomplete|Added a basic explanation. Still needs some work.}}
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The comic is inspired by the recent {{w|BICEP2}} discovery of gravitational waves from the early universe, hence providing evidence for the {{w|Inflation_(cosmology)|cosmic inflation}} hypothesis. Megan is excited about this and tells Ponytail all about it. She is impressed by the fact that these waves were created when the universe was extremely small and the expanding universe has "imprinted" the gravity waves.
  
She compares this to the nature of a microscope - which optically expands a small image, just like the universe has done to itself. Ponytail is impressed by it until Megan looks at the image captured by the {{w|Wilkinson Microwave Anisotropy Probe|Wilkinson Microwave Anisotropy Probe (WMAP)}}.
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She compares this to the nature of a microscope - which optically expands a small image, just like the universe has done to itself. Ponytail is impressed by it until Megan looks at the actual image captured by the BICEP2 instrument.
  
The concept of an {{w|Metric expansion of space|expanding universe}} is sometimes explained by the "balloon model", where the two-dimensional skin represents our three-dimensional universe and the inflation of the balloon represents expansion over time. But instead of showing a balloon, [[Randall]] uses a basketball, which cannot inflate as easily as a balloon.
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The concept of an expanding universe is often explained by comparing it with a basketball [https://books.google.nl/books?isbn=0691147310], where the leather skin represents our three-dimensional universe and the inflation of the ball represents expansion over time.
  
The elliptical {{w|Mollweide projection}} of this {{w|Cosmic microwave background|cosmic microwave background (CMB)}} image of the sky makes the map look a bit like a basketball. Randall further exaggerates this by superimposing the traditional curves that are visible on a basketball and the {{w|Spalding (sports equipment)|Spalding}} company logo over the original image available at the bottom here. The mentions of scale and basketballs in this comic might be a reference to the "If the Earth were the size of a basketball" comparison, similarly to [[1074: Moon Landing]] and [[1515: Basketball Earth]].
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The elliptical {{w|Mollweide_projection|Mollweide projection}} of most {{w|Cosmic_microwave_background|cosmic microwave background}} images of the sky make the maps look a bit like a basketball. [[Randall]] emphasizes this by superimposing the traditional curves that are visible on a basketball and the {{w|Spalding_(sports_equipment)|Spalding}} company logo over the original image [http://map.gsfc.nasa.gov/media/121238/index.html].
  
Megan and Ponytail are both disconcerted by this, and the title text references the 1996 basketball movie ''{{w|Space Jam}}'' by promising images of main characters Michael Jordan and Bugs Bunny if the polarization of the view is changed to {{w|B-modes|E-mode}}, a type of polarization of the cosmic background radiation arising from the radiation scattering off non-uniform plasma.
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They are both disconcerted by this, and the title text references the 1996 basketball movie ''{{w|Space_Jam|Space Jam}}'' by promising images of main characters Michael Jordan and Bugs Bunny if the polarization of the view is changed to {{w|B-modes|E-mode}}.
  
The image was updated between 7 AM and 8:30 AM EST on May 7. Originally the Spalding logo was shown from left-to-right; however, in the updated image, the Spalding logo is shown in reverse. The WMAP image has the correct orientation in both versions. This was likely due to a mistake on Randall's part, as the comic suggests the universe is contained inside a Spalding basketball. Seen from the inside, the Spalding logo would be shown in reverse, as seen in the updated image. The first image can be found [[Media:inflation first version.png|here]]. Both the original and updated version don't exactly match the pattern on a typical basketball. Most basketballs are divided into eight identical (ignoring reflection) pieces in a pattern that allowed traditional leather basketballs to be made from a single template, while the image shows a pattern that would split a basketball into two types of pieces.
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The image was updated between 7 AM and 8:30 AM EST on May 7. Originally the Spalding logo was shown from left-to-right; however, in the updated image, the Spalding logo (and indeed the entire radiation image) is shown in reverse. This was likely due to a mistake on Randall's part, as the comic suggests the universe is contained inside a Spalding basketball. Seen from the inside, the Spalding logo would be shown in reverse, as seen in the updated image.  
  
 
==Transcript==
 
==Transcript==
:[Megan sits at a computer, conversing with Ponytail.]
 
:Megan: Imprinted on the sky are the gravity waves that were sloshing across the universe when it was ''this'' big.
 
  
:Megan: So really, we're using the entire universe as a giant microscope pointed at itself when it was small.
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[Megan sits at a computer, conversing with Ponytail.]
  
:[Megan turns to face the computer.]
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Megan: Imprinted on the sky are the gravity waves that were sloshing across the universe when it was ''this'' big.
:Ponytail: That's neat.
 
:Megan: Yeah. But...
 
:Ponytail: But what?
 
:Megan: Well, look.
 
  
:Ponytail: Oh. Hmm.
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Megan: So really, we're using the entire universe as a giant microscope pointed at itself when it was small.
:Megan: Yeah.
 
:Ponytail: What...
 
:Megan: I don't know.
 
  
:[Below is an image of the universe showing the cosmic microwave background, featuring a series of circles and the Spalding basketball logo, as though the universe had been imprinted with the image of a basketball.]
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[Megan turns to face computer.]
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Ponytail: That's neat.
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Megan: Yeah. But...
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Ponytail: But what?
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Megan: Well, look.
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Ponytail: Oh. Hmm.
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Megan: Yeah.
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Ponytail: What...
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Megan: I don't know.
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[Below is an infrared-esque image of the universe, featuring a series of circles and the Spalding logo, as though the universe had been imprinted with the image of a basketball.]
  
 
==External links==
 
==External links==
 
*[http://map.gsfc.nasa.gov/media/121238/index.html Original cosmic microwave background image published by NASA.]
 
*[http://map.gsfc.nasa.gov/media/121238/index.html Original cosmic microwave background image published by NASA.]
*[http://upload.wikimedia.org/wikipedia/commons/6/68/Spalding_logo.svg Image of Spalding logo on Wikipedia.]
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{{comic discussion}}
 
{{comic discussion}}
[[Category:Comics featuring Megan]]
 
[[Category:Comics featuring Ponytail]]
 
[[Category:Comics with color]]
 
[[Category:Physics]]
 
[[Category:Basketball]]
 
[[Category:Cosmology]]
 

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