Exponentiation break closures. For example with the integers, exponentiation of an integer (other than $0$) to a negative integer can be a rational number that is not equal to any integer. With the rational numbers exponentiation of a rational number(other than $0/1$) to a rational number is a root which is an algebraic number that is not necessarily a rational number.
Can exponentiation of an algebraic number (other than $0$) by a non rational algebraic number (example: $2^\sqrt{2}$) also result in a non-algebraic number?
Are the reals > $0$ closed under exponentiation? if Yes, what's the proof?