We deal with the theoretical and experimental quantum optics. We utilize ultra-cold atoms (BECs), hot atoms and atoms within a solid lattice. Half of our work is on fundamental quantum physics and half on quantum technology. We were the first to put a single clock in two places simultaneously and are now preparing to put a very large object (on the quantum scale) in a spatial superposition. סn the technology front we deal with atomic clocks, magnetic sensors, acceleration sensors and building blocks for quantum computers. Our work is conducted וn English and we have worldwide collaborations.