Multiparticle states in braided lightlike $\kappa$-Minkowski noncommutative QFT

In this study, we construct a 1+1-dimensional, relativistic, free, complex scalar Quantum Field Theory on a noncommutative spacetime characterized by Lie algebra-type commutators, namely, the lightlike version of $\kappa$-Minkowski. The associated $\kappa$-Poincar\'e quantum group of isometries is quasitriangular, and its quantum R matrix facilitates the definition of a braided algebra of N points that retains Poincar\'e invariance. Leveraging our recent findings, we can now represent the generators of the deformed oscillator algebra as nonlinear redefinitions of undeformed oscillators, which are nonlocal in momentum space. In this representation, the momentum, boost, and charge conjugation operators remain undeformed. The deformation is confined to the creation and annihilation operators. However, this deformation only manifests at the multiparticle level, as the one particle (and antiparticle) states are identical to the undeformed ones. We successfully introduce a covariant, involutive deformed flip operator using the R matrix. The corresponding deformed (anti-)symmetrization operators are covariant and idempotent. We conclude by noticing that P and T are not symmetries of the theory, although PT (and hence CPT) is.