Complete asymptotic expansion of the spectral function of   multidimensional almost-periodic Schrodinger operators
  We prove the complete asymptotic expansion of the spectral function (the integral kernel of the spectral projection) of a Schrodinger operator $H=-\Delta+b$ acting in $R^d$ when the potential $b$ is real and either smooth periodic, or generic quasi-periodic (finite linear combination of exponentials), or belongs to a wide class of almost-periodic functions. 
Leonid Parnovski, Roman Shterenberg
math-ph math.AP math.MP