Pseudo-differential operators have emerged as pivotal tools in modern analysis, generalising classical differential operators to encapsulate non-local behaviour via their symbol calculus. Their ...

The study of global solvability and hypoellipticity of differential operators on manifolds has attained increasing prominence over recent decades. At its core, global solvability investigates the ...

The paper deals with the computation of functions of fractional powers of differential operators. The spectral properties of these operators naturally suggest the use of rational approximations. In ...