Related papers: TeV-photon paradox and space with SU(2) fuzziness
Supersymmetry is one of the best motivated possibilities for new physics at the TeV scale. However, both concrete string constructions and phenomenological considerations suggest the possibility that the physics at the TeV scale could be…
There are observations indicating a possible anomalous transparency of intergalactic space (filled with infrared background light) for extragalactic gamma-rays of very high energy (> 100 GeV). The anomaly is usually associated with effects…
The mysterious very high energy gamma-ray source, TeV J2032+4130, is coincident with the powerful Cygnus OB2 stellar association, though a physical association between the two remains uncertain. It is possible that the detected very high…
Axion-like particles (ALPs) can oscillate to photons and vice versa in electromagnetic fields. The photon-ALP oscillation provides an attractive solution to the apparent transparency of the Universe to TeV photons. The allowed parameter…
We consider the general expressions for the time delay of photons of different energies in the framework of multi-dimensional cosmological models. In models with compactified extra-dimensions (Kaluza-Klein type models), the main source of…
A Lorentz-noninvariant modification of the kinematic dispersion law was proposed in [hep-th/0211237], claimed to be derivable from from q-deformed noncommutative theory, and argued to evade ultrahigh energy threshold anomalies…
The hypothesis that AGN jets might be the sources of the ultra-high energy cosmic rays has originally motivated the venture of TeV gamma ray astronomy. Surprisingly, after the discovery of TeV emission from blazars the attention has shifted…
We analyze observational constraints from TeV astrophysics on Lorentz violating nonlinear dispersion for photons and electrons without assuming any a priori equality between the photon and electron parameters. The constraints arise from…
We explore how the thermal ground states of two mixing and pure SU(2) Yang-Mills theories, SU(2)$_{\tiny\mbox{CMB}}$ of scale $\Lambda_{\tiny\mbox{CMB}}\sim 10^{-4}\,$eV and SU(2)$_{e}$ of scale $\Lambda_{e}\sim 5\times 10^5\,$eV, associate…
The physical reasons in favour of a two dimensional topological model of quantum electrodynamics are discussed. It is shown that in accord with this model there is a new uncertainty relation for photon which is compatible with QED.
The observation of the time delay between the soft emission and the high-energy radiation from cosmological gamma ray bursts can be used as an important observational test of multi-dimensional physical theories. The main source of the time…
We investigate the landscape of constraints on MeV-GeV scale, hidden U(1) forces with nonzero axial-vector couplings to Standard Model fermions. While the purely vector-coupled dark photon, which may arise from kinetic mixing, is a…
We survey operators that can lead to a keV photon line from dark matter decay or annihilation. We are motivated in part by recent claims of an unexplained 3.5 keV line in galaxy clusters and in Andromeda, but our results could apply to any…
Photons may convert into axion like particles and back in the magnetic field of various astrophysical objects, including active galaxies, clusters of galaxies, intergalactic space and the Milky Way. This is a potential explanation for the…
We explore the possibility that dark matter is a pair of vector-like fermionic $\mathrm{SU}(2)_{\rm L}$ doublets and propose a novel mechanism of dark matter production that proceeds through the confinement of the weak sector of the…
We develop a model for a possible origin of hard very high energy spectra from a distant blazar. In the model, both the primary photons produced in the source and secondary photons produced outside the source contribute to the observed high…
At TeV energies, the gamma-ray horizon of the universe is limited to redshifts z<<1, and, therefore, any observation of TeV radiation from a source located beyond z=1 would call for a revision of the standard paradigm. While robust…
Starlight in the Universe impedes the passage of high energy (e.g. TeV) gamma rays due to positron-electron pair production. The history of this stellar radiation field depends upon observations of star formation rate which themselves can…
The thermal relic abundance of Dark Matter motivates the existence of new electroweak scale particles, independent of naturalness considerations. However, most unnatural Dark Matter models do not ensure the presence of new particles charged…
We propose a theory in which the Standard Model gauge symmetry is extended by a new $SU(2)_\ell$ group acting nontrivially on the lepton sector which is spontaneously broken at the TeV scale. Under this $SU(2)_\ell$ the ordinary leptons…