“…In the context of non homogeneous materials (such that electrorheological fluids and smart fluids), the use of Lebesgue and Sobolev spaces L p and W s,p seems to be inadequate, which leads to the study of variable exponent Lebesgue and Sobolev spaces L p(x) and W s,p(x,• ) . Moreover, the study of problems which involves the fractional p(x, • )-Laplacian and the corresponding nonlocal elliptic equations constitutes a promising domain of research in which many mathematicians had contributed (see for example [1,7,11,12,14,21]). Furthermore, this type of problems arise in many physical phenomena such as conservation laws, ultra-materials and water waves, optimization, population dynamics, soft thin films, mathematical finance, phases transitions, stratified materials, anomalous diffusion, crystal dislocation, semipermeable membranes, flames propagation, ultra-relativistic limits of quantum mechanics, we refer the reader to [9,24] for details.…”