In this paper we study the following class of fractional relativistic Schr\"odinger equations: \begin{equation*} \left\{ \begin{array}{ll} (-\Delta+m^{2})^{s}u + V(\varepsilon x) u= f(u) &\mbox{ in } \mathbb{R}^{N}, \\ u\in H^{s}(\mathbb{R}^{N}), \quad u>0 \end{array} \right. \end{equation*} where $\varepsilon>0$ is a small parameter, $s\in (0, 1)$, $m>0$, $N> 2s$, $(-\Delta+m^{2})^{s}$ operato...

In this paper, we are concerned with the following critical fractional Choquard equation$ (-\Delta)^{s}u + V(x)u = (\mathcal{K}_{\mu}*|u|^{2^{*}_{\mu,s}})|u|^{2^{*}_{\mu,s}-2}u, \ u \in D^{s,2}(\mathbb{R}^{N}), $where $ s\in (0,1) $, N\geq 3 \max\{N-4s, 0\}<\mu<N 2^{*}_{\mu,s} \frac{2N-\mu}{N-2s} V(x) is a potential function, and \mathcal{K}_{\mu} Riesz potential. first part of combining ...