The Radon transform apparently was discovered around 1917 if Wikipedia is to be believed. The Cauchy-Crofton theorem is a much older theorem (mid 19th-century). But both ideas are more or less the same. 


Did Radon consider his transform as a generalization of the Cauchy-Crofton theorem? Did he not know about the Cauchy-Crofton theorem?


Links to statements of results:


<http://en.wikipedia.org/wiki/Crofton_formula>


<http://en.wikipedia.org/wiki/Radon_transform>



Historical question Cauchy-Crofton theorem vs. Radon transform
I am looking at the translation of the original paper by Radon. It has only three references: To Minkowski, Funk, and von Weyl. Crofton is not mentioned in the text, and the only mention of Cauchy is irrelevant to your question. This makes it rather unlikely that he knew about it, I think. – Harald Hanche-Olsen Nov 27 2009 at 20:04


