Quantum Localisation Observables and Accelerated Frames

We define quantum observables associated with Einstein localisation in space-time. These observables are built on Poincare' and dilatation generators. Their commutators are given by spin observables defined from the same symmetry generators. Their shifts under transformations to uniformly accelerated frames are evaluated through algebraic computations in conformal algebra. Spin number is found to vary under such transformations with a variation involving further observables introduced as irreducible quadrupole momenta. Quadrupole observables may be dealt with as non commutative polarisations which allow one to define step operators increasing or decreasing the spin number by unity.Comment: 14 page

Inertia of Casimir energy

Moving mirrors are submitted to reaction forces by vacuum fields. The motional force is known to vanish for a single mirror uniformly accelerating in vacuum. We show that inertial forces (proportional to accelerations) arise in the presence of a second scatterer, exhibiting properties expected for a relative inertia: the mass corrections depend upon the distance between the mirrors, and each mirror experiences a force proportional to the acceleration of the other one. When the two mirrors move with the same acceleration, the mass correction obtained for the cavity represents the contribution to inertia of Casimir energy. Accounting for the fact that the cavity moves as a stressed rigid body, it turns out that this contribution fits Einstein's law of inertia of energy.Comment: 10 page

Quantum algebraic representation of localization and motion of a Dirac electron

Quantum algebraic observables representing localization in space-time of a Dirac electron are defined. Inertial motion of the electron is represented in the quantum algebra with electron mass acting as the generator of motion. Since transformations to uniformly accelerated frames are naturally included in this conformally invariant description, the quantum algebra is also able to deal with uniformly accelerated motion.Comment: 10 pages, Frontier Tests of QED and Physics of the Vacuum, Trieste, 5-11/10/200

Motional Casimir force

We study the situation where two point like mirrors are placed in the vacuum state of a scalar field in a two-dimensional spacetime. Describing the scattering upon the mirrors by transmittivity and reflectivity functions obeying unitarity, causality and high frequency transparency conditions, we compute the fluctuations of the Casimir forces exerted upon the two motionless mirrors. We use the linear response theory to derive the motional forces exerted upon one mirror when it moves or when the other one moves. We show that these forces may be resonantly enhanced at the frequencies corresponding to the cavity modes. We interpret them as the mechanical consequence of generation of squeezed fields.Comment: 14 page