The Doctorate student will 1. complete the identification of the modifications of Maxwell's laws in the GMT framework already started by the collaboration (e.g., the Ampère law for Cluster and MMS satellite data). 2. complete the identification of the variation in frequency Δf/f per metre in the GMT framework, due to the energy exchange between the photon and the background electromagnetic field (e.g., laboratory or space interferometry experiments as LISA). 3. for non-linear theories, outside SME, analyse the existence of an effective mass. 4. find solutions of the de Broglie-Proca wave equation (Klein-Gordon type) with a singular source term, describing a frequency shift even in the absence of a background field. 5. study non-linear interactions (photon splitting, merging, photon-photon) with massive photons. The candidate will have completed or be about to complete a Master degree or equivalent in theoretical physics, including quantum field theory, classical and quantum electrodynamics, general and special relativity, ideally with knowledge of astrophysics and cosmology and a strong foundation in mathematical physics. Even if the thesis topic is theoretical, particular attention will be paid to the proposition of measurements in experiments and observations. Previous work related to the subject will be considered favourably. Alternatively, a detailed research proposal should be submitted.
Astrophysical observations are mainly based on electromagnetic signals, read with Maxwell's theory, linear and without photonic mass, possibly approximating a larger theory, such as Newtonian gravity for general relativity. We examine Generalised Maxwellian Theories (GMT) that induce A) modifications of Maxwell's laws B) birefringence for which the refractive index depends on light polarisation and propagation direction C) a shift of the emission frequency of magnetars D) light dispersion for which the group velocity differs from c by a factor proportional to the inverse of the square of the frequency, impacting pulsar signals, Fast Radio Bursts (FRBs), multi- messenger astronomy and graviton mass estimates E) a frequency shift in the vacuum, due to the energy exchange between photon and background fields, causing the reinterpretation of the universe expansion and of dark energy. GMT are either massive (de Broglie-Proca, Bopp, Podolski, Stueckelberg and others) or non-linear (Born-Infeld, von Heisenberg-Euler and others). In modern particle physics, the Standard Model (SM), which respects Lorentz- Poincaré symmetry, does not explain the oscillations and masses of neutrinos, the matter-antimatter unbalance and the dark universe. For the SM, the photon is the only free massless particle. Theories extending the SM based on symmetry breaking (SME theories) lead to an effective, gauge invariant, but anisotropic photon mass.Additional comments
The selection will be based on the candidate's dossier (CV, Master's grades, publications, research proposal, letters of recommendation) and a vidéo audition to be held in November-December 2022. The start date of the contract, currently set at 1 February 2023, may be modified depending on the successful candidate.Web site for additional job details
https: // emploi.cnrs.fr/Offres/Doctorant/UMR7328-ISALAN-026/Default.aspxRequired Research Experiences
Astronomy › Astrophysics
Astronomy › Cosmology
Astronomy: Master Degree or equivalent
FRENCH: BasicContact Information