A noted quantum Physicist Elizur advanced the theory that the collapse of a #quantumwavefunction creates time space.
Just two of interesting outcomes if the theorem cannot be falsified
a) There is no "future", it's nothingness
b) The question of "what's outside the known (spacetime) universe can be answered with "Nothing".
The Universe is bounded by nothing.
Significantly, the latest postulate that dark matter may not exist, and instead the observables may be due to uneven passage of time in denser parts (more quantum wave function collapses) may support Elizurs theory. The so called "lumpy" time.
(My interpretation)
Intuitively, I always thought (b) was the case, but it's nice to have your gut feel confirmed by a theorem.