I notice that beamer has everything in sans-serif by default, including math. In a regular article, simply using \sffamily doesn't cause math to be set in sans-serif. Using \renewcommand{\familydefault}{\sfdefault} doesn't work and the sansmath package sort of works, but seems to produce varying results with respect to whether letters are italic or not (e.g., in beamer \Gamma is not italicized, but with sansmath it is.)
Is there one "right" way to do this?
Edit: another problem is that \sansmath seems to turn \beta into "fi".

