Reminds me of the Tralfamadorians from Slaughterhouse-Five. They are able to see in four dimensions so humans appear as fetuses at one end of the four-dimensional person and dying at the other end.

https://en.wikipedia.org/wiki/Tralfamadore#Slaughterhouse-Fi...

Interesting concept. I wonder if it's compared with spatial 3D space, then how large would the 4th dimension of time be if it were to fit the timeline of a human lifespan

A natural interpretation leads to time being very large and us moving very very fast through it.

It's convenient to model our movement through space-time as occurring at the speed of light. Thus, the faster we move in space, the slower we move in time all the while the length of our space-time velocity vector is invariably c. We can then imagine 1 second of time being interchangeable with 299,792,458m.

...which means that a Tralfamadorian would see an average human as a 6*10^17 meters long snake.

Greg Egan - A Clockwork Rocket (book 1 of the Orthogonal trilogoy, all three of which I recommend)

Aliens in the movie Arrival perceive time in circular fashion, basically live in future and past.

And the movie is based on Ted Chiang’s novella, "Story of Your Life"

Just saying, this is a pretty big spoiler.

Not sci-fi, but the block universe is central to Alan Moore's Jerusalem.

Surely reminds me of Harry Potter and the Prisoner of Azkaban, where Harry is saved by himself as he at some point in the future travels back in time to save himself.

Bill and Ted's Excellent Adventure, but yeah.

The Nolan film "Tenet" is based entirely around the idea of reversible causality.

The 'Dirac Beep' in this short novella (1973):

https://en.wikipedia.org/wiki/The_Quincunx_of_Time

Also, the concept of causality itself is a kind of underlying theme in Hannu Rajaniemi's "The Causal Angel" (2014) (3rd of a series).