If my understanding of the law of conservation is accurate, it implies that the total quantity of matter and energy in the universe, subsequent to the “big bang,” is constant over time, that it does not vary from time to time.
While I am seriously skeptical towards the idea that it is possible to travel through time, the apparent violation of conservation does not by itself preclude the possibility of time travel. It could be that when matter and energy are transported through time, an equal amount of matter and energy is displaced in time, from the traveler’s destination in the direction of the traveler’s origin.
Here is another paradox that arises in connection with the idea of time travel:
If I can travel to any instant of time, then each instant has an existence that is independent of my presence at or absence from any particular instant. Each instant has permanence.
If I travel to the year 1961, I could encounter myself as a ten year old child, yet I would continue to experience my life from the perspective of my current adult self. If I cannot experience life from the perspective of my ten year old self, who has a permanent existence in 1961, then “who” is experiencing that life? If each instant of time has a permanent existence, then what makes this particular instant the “present” rather than some other instant? Why are we experiencing life from the perspective of one particular instant, rather than another?”
“…something can come out of nothing.”
That depends on what you mean by “nothing.” Scientists and philosophers offer speculative theories as to what may have existed before the “big bang.” With the origin of the universe comes the origin of the laws (processes) through which matter, energy, space, and time interact. Once those processes have become manifest, as a result of the “big bang,” they do not modify; they become fixed. Therefore the laws of conservation remain inviolable subsequent to the “big bang.”
Is empty space really “nothing?” Or is it a characteristic of the universe whose existence is a result of the big bang, along with matter, energy, and time?
