Science has nothing to do with the question under discussion. God doesn't exist. You keep misstating my premise. Once again, it is that everything in the universe derives from understandable and knowable physical laws and that nothing supernatural is required. My belief in the non-existence of God is a consequence of that premise combined with other arguments.
Science shows how nothing supernatural is required to explain anything in the universe.
If God is in not in the realm of the supernatural, then there would be physical evidence available to support his existence and belief in him can only be the equal of science if the support for both is equal. Science doesn't state whether or not God exists. It gives us the tools for understanding the universe around us and for separating the truth from the fiction. If there's nothing to show that God's existence is the truth, then it is reasonable to believe that such an existence is purely fictional. So is any belief that cannot be established or strongly suggested to be a fact.