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Anthony Bourdain rediscovers Furr's Law
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This is exactly rocket science
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We'll see if I remember to watch this
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Of course, a 20% error is still precision measurement in astronomy...
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I feel safer already...
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"It's perhaps the first time in modern nuclear physics that fundamentally new information about radioactive decay was captured in a picture taken by a digital camera,"
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Brad DeLong reads pop economics so you don't have to.
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Grrr, the physicsworld link requires logging in, and Googling the title doesn't seem to help. Anyone with access care to say what they've actually looked at and what they're really saying?
Sorry about that. Here's some text from the article, with the relevant citation:
Scientists have known for more than a decade that galaxy clusters emit an unusually large amount of "soft" or low-energy X-rays. A possible explanation is that the centres of the clusters contain vast regions of warm, thermally-radiating gas. If this is the case then spectra of soft X-rays from clusters should contain emission lines -- peaks of intensity at certain wavelengths -- corresponding to the composition of atoms in the gas. Trouble is, the spectra are generally smooth.
An alternative explanation is that electrons in galaxy clusters are colliding with photons in the cosmic microwave background, which is radiation left over from the Big Bang. After these collisions -- known as the inverse Compton effect -- some photons would have energies sufficient to be soft X-rays. Now, Max Bonamente at the University of Alabama in Huntsville and colleagues at the same institution and in Finland have calculated how much such a process could account for the abundance of soft X-rays (Astrophys. J. 668 796).
Ugh. This is why I hate headlines that try to make a lot out of nothing. Glancing at the paper (and the description you've quoted) and guessing at how this could be butchered, it seems that they are saying, "if you assume that all of this gas is thermal (which in many cases it probably isn't), then you will mis-estimate the mass from X-rays." Mass of clusters aside (weak lensing measurements generally don't have 20% accuracy, and the Sunyaev-Zel'dovich effect is still gaining footing), the mass of the universe is well constrained from other techniques... nevermind that individual cluster masses can't tell you too much about the "mass of the universe" anyhow, but knowing the Hubble constant, that the universe is flat, and its age can constrain the total mass (within the horizon at least) fairly well.
Hmm...I thought that was Aahz's law, not Furr's law. The only thing that I can conclude for certain at the moment is that it's been a while since I've used Google Groups's interface and that I hate it.
(It does look like most of the current cites for "Furr's law" are on Uncertain Principles itself.)