A friend says before the universe existed, there was a quantum vacuum that created it. Your thoughts? Does God know all future events, including possible events?
On the first question, if anyone says this then I assume that they do not know much about either quantum mechanics or the big bang model. The concept of a quantum vacuum is only a rational one within an existing universe. A quantum vacuum exists in a volume of space. If there is no space, that what would even be the definition of a quantum vacuum, as a vacuum is space which is not occupied. According to the currently accepted big bang model, before the occurrance of this creation event, not only was there no mass and energy, there was also no time and no space. So, how could a quantum vacuum exist if there is no space for it to exist in? This makes no sense. It sound like an ad hoc hypothesis being proposed by an unbeliever who does not understand physics. Here is the bottom line. The universe was created. It had a beginning, and it apparently came from nothing. This causes us to invoke the Kalaam Cosmological Argument. Premise: Anything which begins to exist was caused to exist. Premise: The universe began to exist. Conclusion: The universe was caused by something outside the universe itself. The quantum vacuum ad hoc hypothesis does not solve this problem.
On your second question, the Bible does not give a definite answer to this theological question. I can tell you my own personal answer to this theological question, based on how I have come to understand what the Bible says. As I understand it, God is all-knowing (omniscient), and God is not affected by time (see the above question, which implies the Creator is timeless). Therefore, he has complete foreknowledge. This would imply that God knows future events, and, in principle, he also knows all potential futures as well (you may want to do some research into Molinism for this idea). Yet, God answers prayers and he allows the future to be affected by what we ask of him. This I am quite sure of because of passages such as Genesis 18 in which God changes his mind based on a request by Abraham. So, my answer to your question is that, as I understand the implications of biblical theology, I believe the answer is yes, but I cannot provide absolute solid biblical proof for this conclusion.