Here three questions can be asked:
1) Which one came first, universe, or laws of gravity and quantum theory?
2) If the universe came first, then how was there spontaneous creation without the laws of gravity and quantum theory?
3) If the laws of gravity and quantum theory came first, then Hawking has merely substituted God with quantum theory and laws of gravity. These two together can be called Hawking’s “Unconscious God”. Therefore we can legitimately ask the question: Who, or what, created Hawking’s unconscious God?
Not only this, but there are other problems also. If the laws of gravity and quantum theory allow universes spontaneously appearing from nothing, then initially there was nothing. Then wherefrom appear those laws of gravity and quantum theory to allow universes appearing spontaneously from nothing? In which container were those two laws of nature?
Now regarding the M-theory: I have already written something on multiverse theory in Bengali. There I have come to the conclusion that if there are an infinite number of universes, then only within that infinite number of universes there will definitely be at least one universe in which life will emerge. If the number of universes is only 10 to the power 500, then it is very much unlikely that any one of them will support life, because no universe will know which set of values the other universes have already taken, and if everything is left on chance, then there is every probability that all the universes will take only those set of values that will not support life. There will be no mechanism that will prevent any universe from taking the same set of values that have already been taken by other universes. There will be no mechanism that will take an overview of all the universes already generated, and seeing that in none of them life has actually emerged will move the things in such a way that at least one universe going to be generated afterwards will definitely get the value of the parameters just right for the emergence of life. Only in case of an infinite number of universes this problem will not be there. This is because if we subtract 10 to the power 500 from infinity, then also we will get infinity. If we subtract infinity from infinity, still then we will be left with infinity. So we are always left with an infinite number of universes out of which in at least one universe life will definitely emerge. Therefore if M-theory shows that it can possibly have 10 to the power 500 number of solutions, and thus there might be 10 to the power 500 number of universes in each of which physical laws would be different, then it is really a poor theory, because it cannot give us any assurance that life will certainly emerge in at least one universe. So instead of M-theory we need another theory that will actually have an infinite number of solutions.