Calling this documentary is only partially true. More of it was speculation of diverse scientists about time travel - it's possibility, possible limitations and like.

Well, what is clear is that their knowledge is limited. And even way of thinking. That Indian (Asian) guy presented much better knowledge about time, and it is not new thing there.

Let's see little one area where time travel exists: books and movies - pardon, that's 2 areas - well not really separated - as we know there was book 'Time Machine' from H. G. Wells, and later was movie, actually 2 of them so far. And no one of those scientists mentioned something very interesting and by me important: Wells-es novel time machine was strictly that - travel only in time. What we can read and watch, and was created later has in most (like 99%) cases combined time and space travel. User needs to set not only destination time but location too. And that's not just time travel then.

I liked in Wells novel that it was pure time travel. Much smarter. And that resulted in interesting situations too.

Ah, and that talk about that wee see past when looking at far stars, galaxies. Not correct. We see the light, not them. And we see the light in moment when it arrives in our eyes. So, we don't see the past. We see presentation of past. If think better, same stays for close objects too - picoseconds instead billions of years, but it is time too. And when are at sci-fi : are those far galaxies real, or maybe just someone projects such image for us ? Hey, idea for movie :-)