Wikipedia:Articles for deletion/Fourier expansion electromagnetic field
It is a notable when combined with Quantization of the electromagnetic field. Perhaps it needs to be moved to a more notable name or merged with that article, but the material is useful and as appropriate to WP as many other esoteric subjects. I don't think that  applies as that policy is currently written. There the main criterion seems to be whether or not it is there to 'instruct' or 'inform'. I believe that the latter is the case here. '''* Edit''' (10:21, 31 March 2011) After looking at the material with fresh eyes and after viewing the other comments, I agree that it does violate  (see my comments below). I still don't think that the article violates it to the extent that the solution should be deletion
— User:TStein, 20:53, 25 March 2011 (UTC)
Stance: keep
Cited policy: WP:NOTTEXTBOOK||WP:NOTTEXTBOOK (Wikipedia:What Wikipedia is not)