Massless spinning particle and null-string on AdS _d : projective-space approach

Abstract

Massless spinning particle and tensionless string models on AdS d background in the projective-space realization are proposed as constrained Hamiltonian systems. Various forms of particle and string Lagrangians are derived and classical mechanics is studied including the Lax-type representation of the equations of motion. After that transition to the quantum theory is discussed. Analysis of potential anomalies in the tensionless string model necessitates introduction of ghosts and BRST charge. It is shown that quantum BRST charge is nilpotent for any d if coordinate-momentum ordering for the phase-space bosonic variables, Weyl ordering for the fermions and cb (γβ) ordering for ghosts is chosen, while conformal reparametrizations and space-time dilatations turn out to be anomalous for the ordering in terms of positive and negative Fourier modes of the phase-space variables and ghosts.

Supertwistor formulation for massless superparticle in AdS5 × S5 superspace

“…extending the ambitwistor string model [71]. Depending on the quantization prescription and the choice of the vacuum [72], [73] we expect it to provide the world-sheet CFT interpretation for the scattering amplitudes in D = 5 N = 8 gauged supergravity or to produce D = 10 N = 2B higher-spin massless supermultiplets compactified on AdS 5 × S 5 . Generalization to the tensile string model is also feasible and should give an interesting reformulation of the P SU(2, 2|4)/(SO(1, 4) × SO(5)) supercoset action [37], [38].…”

Cubic interaction vertices for continuous-spin fields and arbitrary spin massive fields

“…In the frameworks of world-line particle and twistor-like approaches, higher-spin fields are considered, e.g., in refs. [60] and [61][62][63][64]. Interesting approach for analysing interacting conformal higher-spin fields in curved background is discussed in ref.…”

Spinning particle interacting with electromagnetic and antisymmetric gauge fields in anti-de Sitter space

“…In the absence of the interaction it coincides with odd constraint introduced in [46]. Observe that the minimality principle fixes the homogeneity degree of A m (x): (x • ∂)A(x) = −A(x).…”

“…In Ref. [46] there was proposed massless spinning particle model in Ad S d realized as the projective space parametrized by the homogeneous coordinates. Three first-class constraints of the model (one odd and two even) span minimal world-line supersymmetry algebra extended by the gauged space-time dilatations.…”