Consider the family of Besov spaces $ B_{p,q}^{s}(\mathbb{R})$ with $ 0<p,q \leq \infty$ and $ s \in \mathbb{R}$ . Is there a natural way to define spaces of generalized functions $ f(t,x) \in \mathcal{S}'(\mathbb{R}^2)$ such that, for any test function $ \varphi \in \mathcal{S}(\mathbb{R})$ , we have $ $ \langle f(t,\cdot), \varphi(t) \rangle \in B_{p_1,q_1}^{s_1}(\mathbb{R})Read more