a time machine is impossible because if it was EVER possible even 1 thousand years from now, we would have time travelers visiting constantly.
What has happened, has happened and nothing can change that.
What has happened, has happened and nothing can change that.
How would we ever know? Once something was changed, everything would be changed. All memories would be changed as well...
Some things are beyond human comprehension.
Einstein’s Theory of Relativity does not preclude the development of a Time Machine.
A Time Machine may be possible, but it would be impractical.
The Universe is not static: everything in it is in constant motion.
Even if you were to create a ‘Time Machine’ it would kill you if you ever used it.
Even if you travelled to just one second in the past or future, you would find yourself in inter-galactic space with no air to breathe and no way to get back................
My take is slightly different. If time travel is possible then an infinite number of copies of the universe must exist. If i can travel back one year, then why not ten. If i can travel back ten and you can travel back 3 and Joe can travel back 100....well this is only possible if every state of the universe is saved forever. Well, maybe God is capable of saving every state of the universe, but time travel only is possible if an infinite set of universal states are stored and active.