arXiv subjects

Marc-Thierry Jaekel

Publications and source records attributed to Marc-Thierry Jaekel.

58 records · Page 4Linked to original sources

arXiv1995

Acceleration of Quantum Fields

We analyze the transformation of quantum fields under conformal coordinate transformations from inertial to accelerated frames, in the simple case of scalar massless fields in a two-dimensional spacetime, through the transformation of particle number and its spectral density. Particle number is found to be invariant under conformal coordinate transformations to uniformly accelerated frames, which extends the property already known for vacuum. Transformation of spectral density of particle number exhibits a redistribution of particles in the frequency spectrum. This redistribution is determined by derivatives of phase operators with respect to frequency, that is by time and position operators defined in such a manner that the redistribution of particles appears as a Doppler shift which depends on position in spacetime, in conformity with Einstein equivalence principle.

quant-ph↗

arXiv1995

Mechanical Effects of Radiation Pressure Quantum Fluctuations

As revealed by space-time probing, mechanics and field theory come out as complementary descriptions for motions in space-time. In particular, quantum fields exert a radiation pressure on scatterers which results in mechanical effects that persist in vacuum. They include mean forces due to quantum field fluctuations, like Casimir forces, but also fluctuations of these forces and additional forces linked to motion. As in classical electron theory, a moving scatterer is submitted to a radiation reaction force which modifies its motional response to an applied force. We briefly survey the mechanical effects of quantum field fluctuations and discuss the consequences for stability of motion in vacuum and for position fluctuations.

quant-ph↗

arXiv1995

Quantum Fluctuations and Inertia

Vacuum field fluctuations exert a radiation pressure which induces mechanical effects on scatterers. The question naturally arises whether the energy of vacuum fluctuations gives rise to inertia and gravitation in agreement with the general principles of mechanics. As a new approach to this question, we discuss the mechanical effects of quantum field fluctuations on two mirrors building a Fabry-Perot cavity. We first put into evidence that the energy related to Casimir forces is an energy stored on field fluctuations as a result of scattering time delays. We then discuss the forces felt by the mirrors when they move within vacuum field fluctuations, and show that energy stored on vacuum fluctuations contributes to inertia in conformity with the law of inertia of energy. As a further consequence, inertial masses exhibit quantum fluctuations with characteristic spectra in vacuum.

quant-ph↗

arXiv1995

Quantum Limits in Space-Time Measurements

Quantum fluctuations impose fundamental limits on measurement and space-time probing. Although using optimised probe fields can allow to push sensitivity in a position measurement beyond the "standard quantum limit", quantum fluctuations of the probe field still result in limitations which are determined by irreducible dissipation mechanisms. Fluctuation-dissipation relations in vacuum characterise the mechanical effects of radiation pressure vacuum fluctuations, which lead to an ultimate quantum noise for positions. For macroscopic reflectors, the quantum noise on positions is dominated by gravitational vacuum fluctuations, and takes a universal form deduced from quantum fluctuations of space-time curvatures in vacuum. These can be considered as ultimate space-time fluctuations, fixing ultimate quantum limits in space-time measurements.

quant-ph↗