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this might enlighten you rationalwiki.org/wiki/Pierre-Marie_Robitaille . There was a discussion here on his cosmic background radiation ideas, which really are bizarre. – anna v Sep 1 '15 at 2:44
You are being too kind--indeed inaccurate--by calling it "highly controversial". He's completely wrong and everyone knows it. There's no "controversy" here at all. – Steve B Sep 4 '15 at 13:36*
Looks like you're right, Steve. I saw the rationalwiki link anna v posted above, he's not just making a strange misunderstanding of a physics law, but rather there is some weird motivation about disproving the standard explanation of the cosmic microwave background. – Nanite Sep 8 '15 at 7:07*
Do the above remarks answer the physics question on the page cited above, or are they just irrelevant comments? If the latter why was the following 'comment' deleted by the administrators?
Nanite - You are mistaken. Professor Robitaille has NOT claimed that epsilon/alpha is dependent upon angle. What he has argued is that unless a cavity contains a black material, such as soot, at thermal equilibrium, the radiation within the cavity is NOT black, and so the radiation always depends upon the nature of the cavity walls, contrary to Kirchhoff who asserted, without any experimental evidence, that the radiation is independent of the nature and form of the cavity walls. Also, thermal equilibrium CAN and IS reached by arbitrary materials, but unless the material is black, the radiation is not black. At thermal equilibrium Stewart's Law applies, i.e. emission = absorption. It does not follow that the emission and absorption are total (i.e. black). Arbitrary materials have reflection as well (unless the material is black when reflection = 0). Reflection cannot build up a black field on its own without violating the First Law of Thermodynamics, and so it does not. Reflection can build up a black field only if it can be driven by input of energy via the walls and a black material, such as a piece of carbon in contact with the walls. In the case of arbitrary cavity walls, infusion of heat into the walls will not produce enough photons from the walls to build black radiation inside the cavity because the temperature of the cavity walls will rise, and thereby drop out of thermal equilibrium.