As far as I understand a Universal Quantum Simulator can simulate any quantum system and thus anything that exists in the universe. Also, a quantum computer can implement such a quantum simulator. Further, from what I've read, a quantum computer does not have the ability to compute something that is not computable by a classical Turing Machine, although it can perform certain computations much more efficiently.
However, I recently saw this: Classical problem becomes undecidable in a quantum setting. The actual paper: Quantum measurement occurrence is undecidable
I don't understand this, unfortunately, so I wanted to ask, does this mean that physics is not computable by a classical computer (Turing Machine)? What about by a quantum computer? Or is this article saying something different altogether?