Explain xkcd: It's 'cause you're dumb.
From the xkcd store explanation of the shirt:
The graph [...] is data from the COBE mission, which looked at the background microwave glow of the universe and found that it fit perfectly with the idea that the universe used to be really hot everywhere. This strongly reinforced the Big Bang theory and was one of the most dramatic examples of an experiment agreeing with a theory in history -- the data points fit perfectly, with error bars too small to draw on the graph. It's one of the most triumphant scientific results in history.
The solid line represents the theoretical radiation for a blackbody at 2.73 K according to Planck's Law (derived as early as 1900 by Max Planck). The theory is that the blackbody in question was in fact the universe at the point when it had cooled down enough to allow photons to escape, and the fact that this light is in the infrared is due to the redshift which occurs more as astronomical objects are more distant because of the expansion of the universe; as this light has been travelling since close to the beginning of the universe, the portion that is reaching us right now came from very far indeed.
The title text praises viewers who can identify where this equation and corresponding graph come from (without consulting this wiki, of course).
- [Graph of cosmic microwave background radiation: Y axis is energy density, X axis is frequency in GHz. Energy density peaks at 160.4 GHz.]
- I(f) = ((2hf^3)/(c^2))*(1/(e^(hf/(kT))-1))
- It works, bitches.
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It's also commonly called "Microwave Background Radiation" because where the radiation peaks at 160.4 GHz is in the microwave range of the electromagnetic spectrum. --Dangerkeith3000 (talk) 18:02, 13 March 2013 (UTC)
- Title Text Meaning
As can easily be seen from the page's history, Dgbrt and I have been locked in a minor edit war over the meaning of the title text. I claim that Randall is simply complimenting the readers who happen to know what the formula and curve mean. Dgbrt thinks otherwise; I will let him explain his interpretation.
Please add to this discussion so we may come to a consensus on its meaning. Thanks. --Quicksilver (talk) 23:18, 25 August 2013 (UTC)
Glad to oblige. I think we need to draw a distinction between what Randall means and what some people might like him to mean. Many people don't agree that the universe started with a Big Bang, whether because they're cosmologists who support an alternative scientific theory, or because they're young earth Creationists who hold that God created the universe about 6000 years ago, or because they're philosophers who hold it self-evident that something can't come out of nothing, or for whatever reason.
Now, I'm not going to say which of those (if any) I believe, because it really doesn't matter in this context - and neither is it important (in this context) what Quicksilver or Dgbrt believes. What we have to keep clear in our minds is that this site is about explaining the cartoons, not projecting particular philosophical standpoints onto Randall's mildly ambiguous phrasing. (When he wrote it, I doubt very much whether he realised he was writing ambiguously.)
The xkcd series, throughout its history, shows not only Randall's firm belief in the scientific method for establishing plausible explanations of the way the universe works, but also his antipathy towards historical explanations that seem to be at odds with observable evidence and even historical record. See #803 and #1255 for obvious examples.
Given Randall's known love of science and the absence of any firm clues that he was being heavily ironic and running massively against type, I think we have to conclude that he was either praising those who could identify the science he was talking about, or just possibly was trying to cause a Wikipedia search spike! --BinaryDigit (talk) 07:17, 8 April 2014 (UTC)
So no one's gotten the bonus points yet?! He was asking to identify the science in question. When he says "It works", I'm sure he was not meaning that blackbody radiation works. This graph was the key to one of the biggest leaps in human understanding.--ChrisfromHouston
) 06:23, 8 September 2014 (UTC)