Massive spinning bosons on the celestial sphere

Conformally soft gluons are conserved currents of the Celestial Conformal Field Theory (CCFT) and generate a Kac-Moody algebra. We study celestial amplitudes of Yang-Mills theory, which are Mellin transforms of gluon amplitudes and take the double soft limit of a pair of gluons. In this manner we construct the Sugawara energy-momentum tensor of the CCFT. We verify that conformally soft gauge bosons are Virasoro primaries of the CCFT under the Sugawara energy-momentum tensor. The Sugawara tensor though does not generate the correct conformal transformations for hard states. In Einstein-Yang- Mills theory, we consider an alternative construction of the energy-momentum tensor, similar to the double copy construction which relates gauge theory amplitudes with gravity ones. This energy momentum tensor has the correct properties to generate conformal transformations for both soft and hard states. We extend this construction to supertranslations.

Section: Introductionsupporting

confidence: 73%

On Sugawara construction on celestial sphere

Fan

Fotopoulos

Stieberger

et al. 2020

“…where m and s here are mass and spin characteristic numbers of the particle produced in the interaction of particles i and j. It is easy to check that this readily holds true for the interaction of two spinning massless particles producing a spinning massive particle that was discussed in [36].…”

Section: Casimir Operators and Characteristic Numbersmentioning

confidence: 82%

“…Double copy construction of celestial amplitudes was outlined in [43]. In [35,36] the authors of the current work tabulated the explicit constraints on celestial amplitudes implied by Poincaré symmetry (based on conformal Ward identities and momentum conservation), making use of the representation of Lorentz generators and massless [21], as well as newly established massive momentum generators on the celestial sphere.…”

Section: Jhep11(2020)149mentioning

confidence: 99%

“…Amplitudes are mapped to the celestial sphere by the Pasterski-Shao-Strominger (PSS) prescription [11,12] with extension to massive spinning external legs in [36]…”

Section: Kinematic Definitions and Amplitude Map To The Celestial Spherementioning

confidence: 99%

“…The map to the celestial sphere for Minkowski space scattering amplitudes with external particles of various masses and (bosonic) spins has been worked out in [11,12,36], and the map was performed for particular amplitude examples in [11, 13-15, 17, 18, 26, 28, 29, 42]. A somewhat different variation of this map was considered in [16,19,20].…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Relativistic partial waves for celestial amplitudes

Law

Zlotnikov

2020

Self Cite

The formalism of relativistic partial wave expansion is developed for four-point celestial amplitudes of massless external particles. In particular, relativistic partial waves are found as eigenfunctions to the product representation of celestial Poincaré Casimir operators with appropriate eigenvalues. The requirement of hermiticity of Casimir operators is used to fix the corresponding integral inner product, and orthogonality of the obtained relativistic partial waves is verified explicitly. The completeness relation, as well as the relativistic partial wave expansion follow. Example celestial amplitudes of scalars, gluons, gravitons and open superstring gluons are expanded on the basis of relativistic partial waves for demonstration. A connection with the formulation of relativistic partial waves in the bulk of Minkowski space is made in appendices.

Asymptotic dynamics on the worldline for spinning particles

Bonocore

2021

There has been a renewed interest in the description of dressed asymptotic states à la Faddeev-Kulish. In this regard, a worldline representation for asymptotic states dressed by radiation at subleading power in the soft expansion, known as the Generalized Wilson Line (GWL) in the literature, has been available for some time, and it recently found applications in the derivation of factorization theorems for scattering processes of phenomenological relevance. In this paper we revisit the derivation of the GWL in the light of the well-known supersymmetric wordline formalism for the relativistic spinning particle. In particular, we discuss the importance of wordline supersymmetry to understand the contribution of the soft background field to the asymptotic dynamics. We also provide a derivation of the GWL for the gluon case, which was not previously available in the literature, thus extending the exponentiation of next-to-soft gauge boson corrections to Yang-Mills theory. Finally, we comment about possible applications in the current research about asymptotic states in scattering amplitudes for gauge and gravity theories and their classical limit.