Let's say we have three broad possibilities: time is point-like or doesn't exist, time is linear, time is a branching tree where a different universe exists for

Let's say we have three broad possibilities: time is point-like or doesn't exist, time is linear, time is a branching tree where a different universe exists for every possible outcome (this is a bastardization of the Copenhagen theorem, but is discussed). Closed time-like curves is implied if time is linear in the way most people think of it (B happens after A). If time is a point-like construct, or if time is emergent from observation, or if time is a branching tree, then the problem of closed time-like curves goes away. For example, physicist Carlo Rovelli's theories are based on the concepts that "time itself disappears at the most fundamental level", and "that time is merely a function of our “blurred” human perception".[1] There are also several ways of time being linear, if that's the case, that are different than current approached. For example, Nicholas Gisin [2] applied intuitionist mathematics and showed that time might be linear but also have an inherent fluidity similar to quantum mechanics. The above is just the start of a conversation. There's also contractible vs non-contractible closed time-like curves [3], and the Novikov self-consistency principle [4]. The main point is that 'always' in physics is rarely accurate, over sufficient time lengths. The secondary point is that when we start adjusting the metrics of an observer, we start changing what we define as travel (if I stand still and the space around me is deformed such that my observed location is now 10m away, have I travelled?). The tertiary point is that we are still actively theorizing and experimenting about time, with many ongoing competing theories - we just don't know enough yet to say that FTL travel is or is not possible (look at Novikov's experiments proving Bell theorem 'spooky action at a distance'). [1] https://www.theguardian.com/books/2018/apr/14/carlo-rovelli-exploding-commonsense-notions-order-of-time-interview https://www.theguardian.com/books/2018/apr/14/carlo-rovelli-... [2] https://en.wikipedia.org/wiki/Nicolas_Gisin https://en.wikipedia.org/wiki/Nicolas_Gisin [3] https://en.wikipedia.org/wiki/Closed_timelike_curve#Contractible_versus_noncontractible https://en.wikipedia.org/wiki/Closed_timelike_curve#Contract... [4] https://en.wikipedia.org/wiki/Novikov_self-consistency_principle https://en.wikipedia.org/wiki/Novikov_self-consistency_princ...