Well, planck's energy distribution of black bodies can be derived perfectly from the assumption that energy exists in discrete packages. the only explaination for this is that photon is discrete particles, so that 1 energy package= 1-photon package, 2 enerage package= 2-photons package
planck's finding really is mind boggling... I'm still trying to understand it fully... i read the above in a book from barnes 'n nobles, it shows the how planck first "accidently" derive it when trying to improve Wilhelm Wien's distribution, then comin up with a explaination to it....

nice free learning from barnes n' nobles.
this has indeed shaken my understanding of continuum...it troubles me to think that one almost perfectly validated concept does not go with another almost perfectly validated concept...
Anyway, how is electromagnetic field defined? another test "particle"... well the existence of photon must still rely on other "particles" regardless of whether not it is a particle...
i think that something is missing regarding fundamental definitions here.