The deformation-stability fundamental length and deviations from c

A fundamental length (or time) is conjectured in many contexts. The “stability of physical theories principle” provides an unambiguous derivation of the stable structures that Nature might have chosen for its algebraic framework. 1/c1/c and ℏ are the deformation parameters that stabilize the Galilean and Poisson algebras. The stability principle applied to the Poincaré–Heisenberg algebra, yields two deformation parameters defining two length (or time) scales. One of the scales is probably related to Planckʼs length but the other might be much larger. This is used as working hypothesis to compute deviations from c in speed measurements of massless particles.

► Fundamental length as one of the deformation parameters of the Poincaré–Heisenberg algebra.
► Conjecture that one of the deformation parameters is much larger than Planckʼs length.
► Deviations from c in speed measurements of massless wave packets.