Sharp L2 estimates of the Schrodinger maximal function in higher dimensions

We show that, for n >= 3, limt(t -> 0) e(it Delta) f (x) = f (x) holds almost everywhere for all f is an element of H-s (R-n) provided that s > n/2(n+1). Due to a counterexample by Bourgain, up to the endpoint, this result is sharp and fully resolves a problem raised by Carleson. Our main theorem is a fractal L-2 restriction estimate, which also gives improved results on the size of the divergence set of the Schrodinger solutions, the Falconer distance set problem and the spherical average Fourier decay rates of fractal measures. The key ingredients of the proof include multilinear Kakeya estimates, decoupling and induction on scales.