I recently heard about energy "not being conserved" in General Relativity and i had doubts. Is this true, cause the following questions deeply worry me if that is the case?:
- Wasn't the whole point of introducing the concept of energy in Classical Physics that it was conserved?
- And isn't it true that the theory of Quantum Mechanics, despite everything else, has a form of energy "that is conserved"? Why wasn't the expression for energy "tweaked a bit" in GR so that a conserved quantity is reached at? [Isn't this how a conserved energy was successfully introduced in QM].
- So, what about Noether's theorem? If a physical theory of dynamics stays the same for all time, there must be a quantity called energy conserved in that theory, ryt? [Or, did i get it wrong]. Then, does GR predict its own in-applicability at different times? [I don't even know how that works].
Note: I have no prior knowledge of the GR theory, except rumors that a violation of the principle of energy conservation is inbuilt in it.
Edit to prove my question is not a duplicate: This question addresses the same problem essentially, but asks only if energy can be lost or gained from the universe as a whole. But I am asking that and the various implications of such a violation and therefore the answers there do not answer my question [at least adequately].