Originally Posted by gideongallery

both of you are missing the point in 4 dimensional space time there is no alternative timeline
there is only one time line.

Under that situation traveling forward in time (how we do) results in cause always preceeding effect.
Reverse the direction of time (time traveling into the past) effect always preceeds cause.

There is no two ways about it.

The only way you can get an alternative reality is by creating a perpendicular dimension vtime= 5th dimension)

watch this video to understand 10d existance.

the point is Predestination paradox is the opposite solution (vs alternative timelines) to the grandfather paradox.

You can't have both, and since the movie clearly had a predestination paradox you can't have alternative timelines.

Temporal mechanics 101, which unfortunately the writer of the second movie did not understand, hense the biggest fuckup in franchise history.