198 citations · 3.3k across the 147 of their papers we have counts for
10 papers · 1 filter
Nontrivial spacetime topology, CPT violation, and photons
Frans R. Klinkhamer
A physical mechanism for CPT violation is reviewed, which relies on chiral fermions, gauge interactions, and nontrivial spacetime topology. The nontrivial topology can occur at the…
Spacetime foam and high-energy photons
F. R. Klinkhamer, C. Rupp
It is shown that high-energy astrophysics can provide information on the small-scale structure of spacetime.
More on a possible energy dependence of Theta_13 in vacuum neutrino oscillations
Frans R. Klinkhamer
Vacuum neutrino-oscillation probabilities from a simple three-flavor model with both mass-square differences and timelike Fermi-point splittings have been presented in a previous a…
Vacuum Cherenkov radiation and photon triple-splitting in a Lorentz-noninvariant extension of quantum electrodynamics
C. Kaufhold, F. R. Klinkhamer
We consider a CPT-noninvariant scalar model and a modified version of quantum electrodynamics with an additional photonic Chern-Simons-like term in the action. In both cases, the L…
Photon-propagation model with random background field: Length scales and Cherenkov limits
F. R. Klinkhamer, C. Rupp
We present improved experimental bounds on typical length scales of a photon-propagation model with a frozen (time-independent) random background field, which could result from ano…
Maxwell-Chern-Simons theory for curved spacetime backgrounds
E. Kant, F. R. Klinkhamer
We consider a modified version of four-dimensional electrodynamics, which has a photonic Chern-Simons-like term with spacelike background vector in the action. Light propagation in…
Merging gauge coupling constants without Grand Unification
F. R. Klinkhamer, G. E. Volovik
The merging of the running couplings constants of the weak, strong, and electromagnetic fields does not require the unification of these gauge fields at high energy. It can, in fac…
Possible energy-dependence of Theta_13 in neutrino oscillations
Frans R. Klinkhamer
A simple three-flavor neutrino-oscillation model is discussed which has both nonzero mass differences and timelike Fermi-point splittings, together with a combined bi-maximal and t…
Coexisting vacua and effective gravity
F. R. Klinkhamer, G. E. Volovik
Our Universe may be a domain separated by physical phase boundaries from other domain-Universes with different vacuum energy density and matter content. The coexistence of differen…
Lorentz and CPT violation: a simple neutrino-oscillation model
Frans R. Klinkhamer
We present a three-parameter model for three flavors of massless left-handed neutrinos with Fermi-point splitting and tri-maximal mixing angles. One of these parameters is the T-vi…