Just watched Donnie Darko and this part of the Philosophy of Time Travel caught my attention, in Stargate SG1 the portals they use are water based and in Donnie Darko it is said that water and metal are the key elements of time travel, the movie also shows these liquid spears that essentially show a person's path, like the path nodes of an NPC from a videogame.

Is the universe deterministic and everyone has their own path node? And how do these water portals work?
https://www.youtube.com/watch?v=BuMINFFMg0U
https://www.youtube.com/watch?v=fLfPH-Hu44A