"When will we invent a time machine? When will we invent the ability to see backwards in time or vice versa?" This "technology" already exists. If you look light years into the distance, let's say into space - you're seeing the past - literally, because light needs time to travel. So if you could somehow bring your consciousness into a state where it can view things from cosmic distances, unrestricted by time - you can predict both the future and the past, with great accuracy. Now, if you're smart enough, or quick-witted enough - you will figure out what this state is. Everything is already invented, all one needs to naturalize cosmic technology for themselves is a reframing of the mind. Time travel is nothing more than self-possession by your future self. If I said even 15% of what I know - I'd break the rule of choice. Have faith and trudge on, your pain matters too. Scientists think they can travel in time to the past, but when you do - it's not the past anymore. It's the alternate present.