Advances in ultrashort-pulse technology have made it possible to generate electromagnetic pulses with duration as short as few hundred attoseconds. thus approaches the orbital period of a classical atomic electron. This advance holds the promise to map out electronic dynamics inside atoms in real time. It poses a considerable challenge to theory to identify observables and novel information that can be accessed and mapped out by attosecond pulses. We will discuss recent progress and open questions with the help of a few examples. Topics include time-resolved Fano resonances in atoms and quantum graphs, coherent excitation, time-resolved orbital motion in doubly-excited helium, and time-double slit interferences.

Work performed in collaboration with D. Arbo, I. Barna, A. Bärnthaler, M. Drescher, F. Krausz, E. Persson, S. Rotter, J. Wang, M. Wickenhauser