滕飞青年研究员,复旦大学,于2025年3月20日16:00在物质科研楼C座11层1124做题为“Generic spinning binaries from the scattering amplitude perspective”的报告,欢迎感兴趣者参加。

发布时间:2025-03-18浏览次数:214

Topic: Generic spinning binaries from the scattering amplitude perspective

Speaker: Prof. Fei Teng

Coordinates: PCFT C1124, 16:00, Thursday, March 20

 

Abstract: In conventional world-line formalism for spinning binaries in general relativity, one assumes that the dynamical degrees of freedom for spin are the completely captured by the rest frame canonical spin. A spin supplementary condition (SSC) is then necessary to remove redundancies. We study this problem from an amplitude-based field theory perspective. In higher spin field theories, it is notoriously difficult to impose transverse and traceless conditions when interactions are included. We take an alternative approach and keep the additional degrees of freedom. We see that for generic Wilson coefficients, we obtain a system with additional physical degrees of freedom that has physical effect starting at the quadrupole level. It will decouple when we choose special values for Wilson coefficients, and we land back on the dynamics of conventional spinning binaries. The situation is very similar to a symmetry breaking in the classical limit. We also construct a world-line Lagrangian and a classical effective Hamiltonian that completely match the physics mentioned above, which incorporates such additional dynamical degree of freedom. Such generic spinning objects are realized in a world-line formalism, in which the additional degrees of freedom can be removed through a world-line shift when Wilson coefficients take special values. Finally, we propose a few candidates for such generic spinning bodies.