Christianity Today on whether prayers make an external difference:
This means that at the macro level as well as the micro, the idea that the world is fixed and predictable is just wrong, and that arguments against an interventionist God don’t work. So, Wilkinson says, chaos might give “space for God to work in unusual and specific ways within the scientific description of the world”. Again, he quotes John Polkinghorne, who says that chaos means that the world is open to the future: “This means that we can pray and God responds by working in the openness of a chaotic system.”
