Differences between Fictional and Scientific Time Warps

[TheQuestionGuy14]

Hey. So I was curious what are the main differences between:

1) Fiction: Time Loops, like the one seen in Groundhog Day or Edge of Tomorrow

And

2) Scientific: Closed Timelike Curves: Which occur in certain solutions of General Relativity.

Note: Sorry, a lot of the time before I thought time loops from movies were CTCs, thus thought they were real, but someone told me they were different and I want to know the main differences.

 

[.Scott]

The first thing I would say is that CTCs are part of "Mathematical Physics", not "Observed Physics". So they haven't fully lost their "fictional" tag.
That said, there is also the problem that an object in such a loop would collide with itself. That's not a problem for a photon, but us baryon creatures might find the experience pretty crowded.

 

[TheQuestionGuy14]

The first thing I would say is that CTCs are part of "Mathematical Physics", not "Observed Physics". So they haven't fully lost their "fictional" tag.
That said, there is also the problem that an object in such a loop would collide with itself. That's not a problem for a photon, but us baryon creatures might find the experience pretty crowded.

Thanks, but my question is what is different from a time loop and a CTC. And what makes a time loop more fictional than a CTC?

 

[.Scott]

I am not familiar with "Edge of Tomorrow".

So let's take Ground Hog Day. In that case, the world starts out the same at 6am - except for Bill's memory. Bill is allowed to accumulate information over thousands of restarts with nothing else in the world ever changing. There is nothing about a CTC that would provide a mechanism for that.

For CTCs, not all CTCs are created (or imagined) equally. But we can imagine one for our purposes. First, we would need something pretty spectacular to create the right conditions. Perhaps some sort of variation on black holes. Then, as we reached the time/space location where we started, we would see ourselves. So, to make this survivable, let's say we are in a maneuverable spaceship. As we approach our past self, we would maneuver to avoid a collision - while at the same time seeing many other future occurrences of ourselves maneuver to avoid the crowd. After several "orbits" we would be well advised to break out of the loop - which we should be able to do with relatively simple maneuvers.

BUT as I said before, these CTCs may well be completely fictional. They violate some pretty strong rules - such as the prohibition against duplicating quantum states.

 

[TheQuestionGuy14]

I am not familiar with "Edge of Tomorrow".

So let's take Ground Hog Day. In that case, the world starts out the same at 6am - except for Bill's memory. Bill is allowed to accumulate information over thousands of restarts with nothing else in the world ever changing. There is nothing about a CTC that would provide a mechanism for that.

For CTCs, not all CTCs are created (or imagined) equally. But we can imagine one for our purposes. First, we would need something pretty spectacular to create the right conditions. Perhaps some sort of variation on black holes. Then, as we reached the time/space location where we started, we would see ourselves. So, to make this survivable, let's say we are in a maneuverable spaceship. As we approach our past self, we would maneuver to avoid a collision - while at the same time seeing many other future occurrences of ourselves maneuver to avoid the crowd. After several "orbits" we would be well advised to break out of the loop - which we should be able to do with relatively simple maneuvers.

BUT as I said before, these CTCs may well be completely fictional. They violate some pretty strong rules - such as the prohibition against duplicating quantum states.

So really Bill isn't in anything related to a CTC, just movie magic (as his mind magically isn't effected). Right?