Vasiliev equations facilitate globally defined formulations of higher-spin grav- ity in various correspondence spaces associated with different phases of the theory. In the four-dimensional case this induces a correspondence between a generally covariant for- mulation in spacetime with higher-derivative interactions to a formulation in terms of a deformed symplectic structure on a noncommutative doubled twistor space, whereby space- time boundary conditions correspond to sectors of an associative star-product algebra. In this paper, we look at observables given by integrals over twistor space defining composite zero-forms in spacetime that do not break any local symmetries and that are closed on shell. They are nonlocal observables that can be evaluated in single coordinate charts in spacetime and interpreted as building blocks for dual amplitudes. To regularize poten- tial divergencies arising in their curvature expansion from integration over twistor space, we propose a closed-contour prescription that respects associativity and hence higher-spin gauge symmetry. Applying this regularization scheme to twistor-space plane waves, we show that there exists a class of dual amplitudes given by supertraces. In particular, we examine next-to-leading corrections, and find cancellations that we interpret using trans- gression properties in twistor space.
Áreas temáticas de ASJC Scopus
- Física nuclear y de alta energía