Combined data from gamma-ray telescopes and cosmic-ray detectors haveproduced some new surprising insights regarding intergalactic and galacticmagnetic fields, as well as extragalactic background light. We review somerecent advances, including a theory explaining the hard spectra of distantblazars and the measurements of intergalactic magnetic fields based on thespectra of distant sources. Furthermore, we discuss the possible contributionof transient galactic sources, such as past gamma-ray bursts and hypernovaexplosions in the Milky Way, to the observed flux of ultrahigh-energycosmic-rays nuclei. The need for a holistic treatment of gamma rays, cosmicrays, and magnetic fields is a unifying theme for these seemingly unrelatedphenomena.
展开▼
