Radiated Angular Momentum and Dissipative Effects in Classical Scattering.

We present a new formula for the angular momentum J^{μν} carried away by gravitational radiation in classical scattering. This formula, combined with the known expression for the radiated linear momentum P^{μ}, completes the set of radiated Poincaré charges due to scattering. We parametrize P^{μ} and J^{μν} by nonperturbative form factors and derive exact relations using the Poincaré algebra. There is a contribution to J^{μν} due to static (zero-frequency) modes, which can be derived from Weinberg's soft theorem. Using tools from scattering amplitudes and effective field theory, we calculate the radiated J^{μν} due to the scattering of two spinless particles to third order in Newton's constant G, but to all orders in velocity. Our form-factor analysis elucidates a novel relation found by Bini, Damour, and Geralico between energy and angular momentum loss at O(G^{3}). Our new results have several nontrivial implications for binary scattering at O(G^{4}). We give a procedure to bootstrap an effective radiation reaction force from the loss of Poincaré charges due to scattering.