Pointwise Debreu Lexicographic Powers

A linear ordering is Debreu (respectively, pointwise Debreu) if each of its suborderings can be mapped into it with an order-preserving function that is both injective (respectively, locally injective) and continuous (respectively, locally continuous) with respect to the order topology on both spaces. Each Debreu linear ordering is pointwise Debreu, but the converse does not hold. In the context of utility representations in mathematical economics, it has been proved that any lexicographic power with an uncountable exponent fails to be Debreu. We sharpen this result by analyzing lexicographic powers that are pointwise Debreu.