Explain xkcd: It's 'cause you're dumb.
The graph shows the relationship between energy density and frequency for two sources: the solid line represents the theoretical Blackbody Radiation, and the dots represent measurements of the Cosmic Background Radiation. The equation is Planck's Law, derived in 1900 by Max Planck for the energy density of blackbody radiation.
This comic shows the very close match between theory and prediction, showing that the Cosmic Background Radiation looks exactly like a blackbody at 2.73 K, which is what we would expect if the CMB is the result of the light of the Big Bang cooled by the expansion of the universe.
- [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)