OK!

According to theory, time-travel is possible.

BUT!!!!....Here's a tiresome cliche for those who postulate TT theory:
"Some future person goes back in time
and meets and kills his grandfather.
A conundrum"

How do you escape the conundrum?
I have four likely solutions:

(1) Time travel [physically] may not be possible because the human body may be fatally "stretched" by the distorted time-space fabric at the entrance to a TT worm-hole. [The evidence against physical TT is that no TT "tourists" from the future have ever been discovered now or in the past.]

(2) Time travel is only possible for photons, or other energy particle-waves
[wave-particles?] since TT wormholes
may be too-small in diameter to admit
a human being, or even a bullet or virus...Such photonic TT has an interesting potential: Can you record
events from the past, including every public, private and intimate thing you have done, good or bad, by photonic TT
transference????.....
Imagine a future holographic TV channel devoted to "live" past or future events.

(3) A hitherto unknown, non-living &
non-intelligent force, substance or
phenomena may serve as an insurmountable time-travel barrier.
[Speculation? Yes! But it would have been science-fiction speculation in the year 1894 if you claimed that there was a ray or beam of energy that could penetrate thick solid-matter...If you made the claim, two years later, it wouldn't have been speculation anymore,
since Roentgen rays were discovered in 1895.

(4) A known or unknown living and intelligent force or being [Who would have to be Omniscient, Omnipotent and Omnipresent] may permanently prohibit
and prevent physical "time travel" for the very reasons given by the conundrum
of the future TT visitor attempting
to murder his grandfather in the past.

Jacob

(2) Time travel is only