What provides the main support against the inward force of gravity in a main sequence star? What provides support against gravitational contraction in a white dwarf? Explain briefly the physical origins of the different processes. Provide a brief explanation of why there is a critical mass for a white dwarf (the Chandrasekhar limit), above which it will collapse to form a neutron star.

What provides the main support against the inward force of gravity in a main sequence star? What provides support against gravitational contraction in a white dwarf? Explain briefly the physical origins of the different processes. Provide a brief explanation of why there is a critical mass for a white dwarf (the Chandrasekhar limit), above which it will collapse to form a neutron star.