We interpret, in the realm of relativistic quantum field theory, the tangential operator given by Coleman, Mandula [CM67] (see also [MPS16]) as an appropriate coordinate operator. The investigation shows that the operator generates a Snyder-like noncommutative spacetime with a minimal length that is given by the mass. By using this operator to define a noncommutative spacetime, we obtain a Poincaré invariant noncommutative spacetime and in addition solve the soccer-ball problem. Moreover, from recent progress in deformation theory we extract the idea how to obtain, in a physical and mathematical well-defined manner, an emerging noncommutative spacetime. This is done by a strict deformation quantization known as Rieffel deformation (or warped convolutions). The result is a noncommutative spacetime combining a Snyder and a Moyal-Weyl type of noncommutativity that in addition behaves covariant under transformations of the whole Poincaré group.
Discussion 16Conventions 0.1. We use d = n + 1, for n ∈ N and the Greek letters are split into µ, ν = 0, . . . , n. Moreover, we use Latin letters for the spatial components which run from 1, . . . , n and we choose the following convention for the Minkowski scalar product of d-dimensional vectors, a · b = a 0 b 0 + a k b k = a 0 b 0 − a · b. Furthermore, we use the common symbol S (R n,d ) for the Schwartz-space and H for a Hilbert space. * amuch@matmor.unam.mx † vergara@nucleares.unam.mx 2