Have I invented a new theory about the origin of the universe?

Answer

There is already a “theory” that states that the total energy of the universe is zero and always has been. After all, in addition to positive energy, there is such a thing as negative energy, for example the potential energy of gravitation itself. If a planet orbits a star in an elliptical orbit, it moves faster the closer it is and feels more gravitational. The kinetic energy T is then greater; since the total energy E is constant, the potential energy U must be smaller, because T+U=E. Furthermore, the potential energy of gravitation is proportional to M/R, and if R is smaller, M/R is larger! Conclusion: the proportionality factor must have a minus sign, and the potential energy is negative.

If all the mass was packed together at the big bang, then the total potential energy was very negative. But the total positive energy of that hot matter was also very large. And there we have your -infinite + +infinity. But in the same universe. Now infinity is not a number, and it is mathematically incorrect to say that infinity minus infinity is zero. But the reasoning does provide a scenario for ‘creating something out of nothing’. A small quantum fluctuation can thus create a new universe, with its own time and space.

We have to be careful with our language. For example, you write: once there was nothing; but conservation of energy says… Hola, if there was nothing, was there conservation of energy? That is a property of the space in which we live and where there is something. We are a little more comfortable with this quantum fluctuation: it happened in another universe from which our own originated. And so there is a beginning to our time in our universe, but not really to the validity of natural laws.