I want to know if the following proposition is correct or not?
For any integer k, there exists an problem P for which, the minimum possible time complexity of any solution algorithm is $\Omega(n^k)$
Please give me creditable sources such as journal papers, books, etc. about the solution of the above question.
UPDATE: By algorithm I mean standard algorithms as discussed in computational complexity. i.e. an algorithm that for any binary encoded input of size n which corresponds to a problem instance, outputs 0 or 1 (or true or false)