Hello, I have been following lectures found here on the end of the lifecycle of stars (while trying my best not to get distracted by his bow tie) and I have some questions on this. Some of them being general questions and some a bit more detailed. 1. First a more general quesion: I’ve read that adding mass to a small planet would make its volume increase but after it reaches a certain mass, adding more mass to it would actually make the volume shrink. Is this because eventually the mass is not proportional to the pressure force inside? 2. Why does the fusion process of a larger star end faster than a smaller one? I understand it’s because of the larger mass but isn’t there also more fusion particles to go through? Or is the fusion rate not proportional to the mass? 3. According to this video, when the core gets depleted from H+, it collapses while at the same time the star as a whole expands and gets larger. I understand that this is caused by the H-burning shell around the core. However, I would expect more that if the core gets depleted from H+, the star as a whole should shrink in size until a new equilibrium has been reached, that equilibrium being caused by that arisen H-burning shell. Why isn’t it like that? 4. The lecturer explains here that fusion of helium to carbon releases energy. How can this be while I can clearly see that there is no net loss of mass before and after fusion? Is it because of the increased release of binding energy? 5. At 5:00 here he explains that the star shrinks in size while the core expands because of the Heliumflash. I don’t quite understand why the star shrinks at that moment. 6. I understand that for a low mass star, the star eventually sheds its outer layers leaving a core behind that is being prevented from collapsing because of the electron degeneracy pressure (a white dwarf). However, in the case of a very large star that turns into a white dwarf that exceeds the Chandrasekhar limit, the electron degeneracy force is not strong enough to prevent collapse. My question is, how was the electron degeneracy force able to prevent the star’s core from collapsing until it became a white dwarf in the first place? Shouldn’t the core collapse happen even before a large star sheds its outer layers and becomes a white dwarf? 7. If a white dwarf exceeds the Chandrasekhar limit, wat determines it to undergo carbon fusion and explode or to implode and become a neutron star? Apologies for the long post. I'd appreciate a lot if someone could shed some light on these.