People are able to change the past with observations of a quantum systems. https://en.wikipedia...quantum_eraser
Is it possible to create a computer that is more effective at observing a quantum system than a human observer. That would be a new kind of transhumanist entity a Superobserver Genetic algorithms could be utilized to create computer structures as well as programs that could effect the past hundreds of times more effectively than a human observer.
Humans observing reality could then use a superobserver computer program as well as mechanism if they wanted to observe a thing to a preferred effect. Visualize a laser based packet switched network that could use a a superobserver (like the DCQE) to hyperefficientize the send path of the packets because it could retrocausally find the most efficient pathway.