3 problems

In the complex Blum–Shub–Smale model, consider the 20 Questions decision problem: given a complex input and an integer bound, decide whether the input is a nonnegative integer at m…

Let $C$ be an oracle set, let $\mathbb{R}^\infty$ denote the set of all finite real tuples, and let $\kappa$ be an infinite cardinal with $\kappa<2^\omega$. For sets…

Let $\mathbb{H}$ be the halting problem for BSS computation on $\mathbb{R}$, and let a countable set mean a subset of $\mathbb{R}^\infty$ of cardinality at most $\omega$. For sets…