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No energy is being continuously invested by gravity. It is not "keeping the reaction going" in that sense. It's simply freshman physics that tells us that force

No energy is being continuously invested by gravity. It is not "keeping the reaction going" in that sense. It's simply freshman physics that tells us that forces only do work when they act through a distance. Because the star's surface is not moving inward, it is not doing work, i.e., giving energy, to the star. Furthermore, the Sun, for example, is probably slowly expanding right now. It will start to do so in time, at any rate. That is, the work done by gravity on the Sun will be negative during that time, and fusion will continue. You just aren't making any sense. You are either not trained in physics, or have failed to understand what you have learned. You could begin to piece together a better education in it by simply following up on my replies in this thread. Please, take it from me, you do not know what you are talking about, and your concerns are therefore not valid. I thought I could help, but you seem to be a tough case. In short: Forces only do work by acting through a distance. Work is energy. If no work is being done, no energy is being produced. Therefore, gravity is not "energizing" the reaction, because the net motion of the star towards its center is zero when it is in equilibrium. In shorter: No motion => no work. No work => no energy. No energy => no problem.

dogma1138 8y ago
Again I understand that work (kinetic) is distance over time. This ain’t what I’m talking about. The Sun no more extracts energy form gravity to burn than you extract it when you walk but if you turn off gravity then you can’t do either. The Sun and every other star aren’t static they are in constant balance between their outward pressure and the inner force of gravity, gravity doesn’t just stop when the ignition point is achieved, this is what confines the star and allows the fusion reaction to continue. Stars have cycles of expansion and contraction and these are understood they are also entirelry governed by the ratio between gravity and their internal pressure fueled by the fusion reaction. So if the Sun expands it means it is generating more energy than what the current gravitational force confines it in, it would expand until a new balance is reached it cannot expand forever unless you turn off gravity and if it would it would very quickly stop fusing elements because it would expand until it cools beyond the temperature which allows for fusion.

dogma1138 8y ago

Again I understand that work (kinetic) is distance over time. This ain’t what I’m talking about. The Sun no more extracts energy form gravity to burn than you extract it when you walk but if you turn off gravity then you can’t do either. The Sun and every other star aren’t static they are in constant balance between their outward pressure and the inner force of gravity, gravity doesn’t just stop when the ignition point is achieved, this is what confines the star and allows the fusion reaction to continue. Stars have cycles of expansion and contraction and these are understood they are also entirelry governed by the ratio between gravity and their internal pressure fueled by the fusion reaction. So if the Sun expands it means it is generating more energy than what the current gravitational force confines it in, it would expand until a new balance is reached it cannot expand forever unless you turn off gravity and if it would it would very quickly stop fusing elements because it would expand until it cools beyond the temperature which allows for fusion.