Church-Turing Thesis
The Church-Turing Thesis states that everything that is computable can be computed with a Turing machine, although it could take a long time (e.g., exponential time). 1
It is named after Alonzo Church and Alan Turing.
Quantum Computers would not be able to violate the Church-Turing Thesis, but there’s Evidence for Quantum Computers to violate Strong Church-Turning Thesis.