Automatic continuity is equivalent to uniqueness of invariant means

Constraint Problems: Computability Is Equivalent to Continuity

In many practical situations, we would like to compute the set of all possible values that satisfy given constraints. It is known that even for computable (constructive) constraints, computing such set is not always algorithmically possible. One reason for this algorithmic impossibility is that sometimes, the dependence of the desired set on the parameters of the problem is not continuous, whil...

Automatic Continuity of Higher Derivations on JB*-Algebras

Generic Uniqueness and Continuity of Rationalizable Strategies

For a finite set of actions and a rich set of fundamentals, consider the rationalizable actions on a universal type space, endowed with the usual product topology. (1) Generically, there exists a unique rationalizable action profile. (2) Every model can be approximately embedded in a dominance-solvable model. (3) A rationalizable strategy is continuous at a finite type if and only if there is a...

Automatic continuity of almost multiplicative maps between Frechet algebras

For Fr$acute{mathbf{text{e}}}$chet algebras $(A, (p_n))$ and $(B, (q_n))$, a linear map $T:Arightarrow B$ is textit{almost multiplicative} with respect to $(p_n)$ and $(q_n)$, if there exists $varepsilongeq 0$ such that $q_n(Tab - Ta Tb)leq varepsilon p_n(a) p_n(b),$ for all $n in mathbb{N}$, $a, b in A$, and it is called textit{weakly almost multiplicative} with respect to $(p_n)$ and $(q_n)$...

Automatic continuity of surjective $n$-homomorphisms on Banach algebras

In this paper, we show that every surjective $n$-homomorphism ($n$-anti-homomorphism) from a Banach algebra $A$ into a semisimple Banach algebra $B$ is continuous.