A singleton universe doesn’t allow for multiple versions of a single moment to coexist. A closed timelike curve does, and potentially an infinite number of variations all as long as they are continuous in the same curve. It’s also different from a proper many worlds theory with quantum variations. The relationship between causes and effects are mapped differently. Thus it’s its own thing.
That’s a variation of a singleton universe timeline.
A singleton universe doesn’t allow for multiple versions of a single moment to coexist. A closed timelike curve does, and potentially an infinite number of variations all as long as they are continuous in the same curve. It’s also different from a proper many worlds theory with quantum variations. The relationship between causes and effects are mapped differently. Thus it’s its own thing.