The laws of physics as we know them are largely based on a linear time sequence in which events follow a clear cause-and-effect relationship. These causal relationships form the backbone of physical theories, from Newton's laws to Einstein's theory of relativity. But what if there were a law of physics that suggested that not only does the past determine the present, but that the present can also influence the past? This concept is often described as "retroactivity" or, in technical terms, retrocausality. Let's explore how a new law of retrocausality might work and what implications it might have for our understanding of the universe.