In addition to what everyone else has already said, consider this: the “Universe” is by definition everything that exists. There cannot “be” things which do not exist. Therefore the question cannot be answered because it presupposes something could exist which is not part of the universe.
No, it’s a logical answer. The definition of the word universe is “everything that exists”
Edit: this is really just another way of expressing that the hypothesis isn’t testable. If something could be measured which could validate or falsify the hypothesis, then that thing being measured would have to exist, and therefore has to be part of the universe.
In addition to what everyone else has already said, consider this: the “Universe” is by definition everything that exists. There cannot “be” things which do not exist. Therefore the question cannot be answered because it presupposes something could exist which is not part of the universe.
That’s a philosophical answer, not a scientific one.
No, it’s a logical answer. The definition of the word universe is “everything that exists”
Edit: this is really just another way of expressing that the hypothesis isn’t testable. If something could be measured which could validate or falsify the hypothesis, then that thing being measured would have to exist, and therefore has to be part of the universe.