Hey there. I have a question concerning the effective masses in silicon. From what I've learned, the effective masses of electrons and holes can be determined from the curvature of the dispersion curve at the extrema. Since the effective mass is inversely proportional to the second derivative of energy, the less curved extrema represent the heavier electrons or holes. The effective mass tables give values of 0,92 (m*/m0) and 0,19 (m*/m0) for the electrons and 0,52 (m*/m0) and 0,16 (m*/m0) for the holes in silicon. Basically, the electron is almost twice as heavy as the heaviest hole. Now the problem I'm facing is that the dispersion curves aren't that diverse from my point of view. So is there a flaw in my way of thinking and why are the electrons heavier in silicon. Thanks in regard.