In the dispute between the Geonim and Rabbenu Tam over the definition of nightfall, I have seen the Rambam claimed by either side - each claiming that in the Mishneh Torah he held like them.
My question is: How does the Rambam hold about shkiah and tzet ha-kokhavim? Does he hold of one shekiah or two? Does he equate shkiah with the actual sinking of the sun below the horizon, with the appearance of three stars, or both? Does he hold like the Geonim or like Rabbenu Tam?