 When "F" is formally "p"-adic but that there does not exist any proper "algebraic" formally "p"-adic extension of "F", then "F" is said to be "p"-adically closed.For example, the field of "p"-adic numbers is "p"-adically closed, and so is the algebraic closure of the rationals inside it (the field of "p"-adic algebraic numbers).If "F" is "p"-adically closed, then