I was discussing with a student the other day about the possibilities of time travel. They contended that it was possible to time travel since any time traveler would clearly hide their abilities in order to not affect/obscure/ruin the present. The argument is valid; it maintains the belief that changing the present from the future affects the past in the future and the future future; however, what's the harm in at least informing someone, anyone, about the possibilities of time travel?
Is it absolute that time travel does not exist because we, the collective public, don't know about it yet? Why can't it be possible that the knowledge has been bequeathed to someone, somewhere? Isn't it also possible that the future has been impacted from people coming from the future and affecting the past (our present or near-future)? Could there be some collection of laws that dictate time travel--the who, what, where, when and why? Is it something reserved and protected after some type of catastrophe or malfunction? Or it is reserved only for some cataclysmic event which must be reserved or prevented, e.g. asteroid, alien invasion, etc.?
As we continued our conversation, I began thinking more about Professor Stephen Hawking, famed physicist who has compacted his entire body of work on time travel into a single sentence which resonates with much more: "Where are all the time travelers?"
After a brief Google search I found this little ditty: an article about Hawking hosting a party for time travelers in which he only announced the party the evening after. Mind blown.
Spoiler: no one attended. At least, he claims no one attended.