Twistorial Foundation for the Classical Double Copy

Radiation and the classical double copy for color charges

We construct perturbative classical solutions of the Yang-Mills equations coupled to dynamical point particles carrying color charge. By applying a set of color to kinematics replacement rules first introduced by Bern, Carrasco and Johansson, these are shown to generate solutions of d-dimensional dilaton gravity, which we also explicitly construct. Agreement between the gravity result and the g...

Static spherically symmetric Kerr-Schild metrics and implications for the classical double copy

We discuss the physical interpretation of stress-energy tensors that source static spherically symmetric Kerr-Schild metrics. We find that the sources of such metrics with no curvature singularities or horizons do not simultaneously satisfy the weak and strong energy conditions. Sensible stress-energy tensors usually satisfy both of them. Under most circumstances, these sources are not perfect ...

On the mathematical foundation of classical thermodynamics

Double Schubert Polynomials for the Classical Groups

For each infinite series of the classical Lie groups of type B, C or D, we introduce a family of polynomials parametrized by the elements of the corresponding Weyl group of infinite rank. These polynomials represent the Schubert classes in the equivariant cohomology of the appropriate flag variety. They satisfy a stability property, and are a natural extension of the (single) Schubert polynomia...

Reflective Oracles: A Foundation for Classical Game Theory

Classical game theory treats players as special—a description of a game contains a full, explicit enumeration of all players—even though in the real world, “players” are no more fundamentally special than rocks or clouds. It isn’t trivial to find a decision-theoretic foundation for game theory in which an agent’s coplayers are a non-distinguished part of the agent’s environment. Attempts to mod...