bilby
Fair dinkum thinkum
- Joined
- Mar 6, 2007
- Messages
- 39,580
- Gender
- He/Him
- Basic Beliefs
- Strong Atheist
The future is not observable from the reference frame of those for whom it is the future. But it is observable from other frames of reference, for which it is the past.In any event, the future is not observable. Maybe it is most correct to say that the future has never been observed from any present.
Observers in different reference frames need not agree on the order in which observed events occurred; There is no universally agreed "now", and "future" or "past" are defined by reference to "now".
There is only a "present" if all those using the term share a reference frame.
No human has ever travelled at relativistic velocities, so all humans agree on a "present" (to a precision so high as to render the disagreement undetectable*). But that doesn't make simultaneity universal, any more than "nature abhors a vacuum" was true before any human had been to space.
https://en.wikipedia.org/wiki/Relativity_of_simultaneity
* The Apollo astronauts have experienced the most relativistic time dilatation of any human, at around 3 to 4 microseconds, which is three or four orders of magnitude below the threshold of human perception at around 10 milliseconds.