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Addendum: Ultrahighenergy cosmicray bounds on nonbirefringent modifiedMaxwell theory
Physical review D: Particles and fields (Impact Factor: 4.86). 07/2008; 77(11). DOI: 10.1103/PHYSREVD.77.117901
Source: arXiv
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Frans R. Klinkhamer, Sep 10, 2013 Available from: Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

 "We have found that the main results of previous studies [12], which assumed structureless particles for these two processes, are robust and that the twosided bound (2.9) remains unchanged when the internal structure of the particles is incorporated. The multimessenger astrophysics program studying highenergy phenomena with ultrahighenergy cosmic rays [33] [34] [35], cosmic gamma rays [36], and cosmic neutrinos [37] has developed the field of astroparticle physics and now serves as a powerful tool to test fundamental physics symmetries. "
Article: Partonmodel calculation of a nonstandard decay process in isotropic modified Maxwell theory
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ABSTRACT: We have performed calculations in the partonmodel approximation of two nonstandard decay processes in isotropic modified Maxwell theory coupled to standard Dirac theory, with a single Lorentzviolating parameter $\kappa$ in the photonic sector. Previous calculations of these processes (vacuum Cherenkov radiation and photon decay) were performed for pointlike particles and a twosided bound on $\kappa$ at the $10^{15}$ level was obtained from data on ultrahighenergy cosmic rays and cosmic gamma rays. The partonmodel results change the decay rates by about an order of magnitude but give essentially the same bound on $\kappa$ because of the large experimental errors in the energy determination of the cosmic primaries.Physical Review D 04/2015; 92(2). DOI:10.1103/PhysRevD.92.025007 · 4.86 Impact Factor 
 "3 As emphasized in Ref. [25] and reiterated in Refs. [8] [9], these bounds require as only input the mere existence, at the top of the Earth's atmosphere, of charged cosmicray primaries with travel lengths of a meter or more. Hence, these bounds are independent of the distance to the (astronomical) source. "
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ABSTRACT: Present and future ultrahighenergycosmicray facilities (e.g., the South and North components of the Pierre Auger Observatory) and TeVgammaray telescope arrays (e.g., HESS and CTA) have the potential to set stringent bounds on the nine Lorentzviolating parameters of nonbirefringent modified Maxwell theory minimally coupled to standard Dirac theory. A concrete example is given how to obtain, in the coming decennia, twosided bounds on the eight anisotropic parameters at the 10^{20} level and an upper (lower) bound on the single isotropic parameter at the +10^{20} (10^{16}) level. Comparison is made with existing and potential direct bounds from laboratory experiments. Comment: 14 pages, v4: further clarifications addedPhysical review D: Particles and fields 08/2010; 82(10). DOI:10.1103/PHYSREVD.82.105024 · 4.86 Impact Factor 
 "Modified Maxwell theory is an Abelian U(1) gauge theory with a Lagrange density that consists of the standard Maxwell term and an additional Lorentzviolating bilinear term [4] [5] [6] [7]. The vierbein formalism is particularly wellsuited for describing Lorentzviolating theories in curved spacetime, since it allows to distinguish between local Lorentz and general coordinate transformations [8] and to set the torsion identically to zero. 2 part of the action : "
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ABSTRACT: A Lorentznoninvariant modification of quantum electrodynamics (QED) is considered, which has photons described by the nonbirefringent sector of modified Maxwell theory and electrons described by the standard Dirac theory. These photons and electrons are taken to propagate and interact in a Schwarzschild spacetime background. For appropriate Lorentzviolating parameters, the photons have an effective horizon lying outside the Schwarzschild horizon. A particular type of Compton scattering event, taking place between these two horizons (in the photonic ergoregion) and ultimately decreasing the mass of the black hole, is found to have a nonzero probability. These events perhaps allow for a violation of the generalized second law of thermodynamics in the Lorentznoninvariant theory considered.Physics Letters B 09/2009; 682(3682):316321. DOI:10.1016/j.physletb.2009.11.020 · 6.02 Impact Factor