Modern astronomical observations prove that dark matter and dark energy are the bedrocks of the modern theory of the Universe. These phenomena cannot be grounded in the known laws of physics, and they call for hypothetical new particles and fields predicted by extensions of the Standard Model of particle physics. In the context of cosmology, dark matter stems from the processes in the early Universe that create this new form of matter, which is then sufficiently stable to survive to the present day. In the context of particle theory, the stability of dark matter implies new conservation laws, resulting from new fundamental symmetries.

The simplest candidates for dark matter, such as neutral Weakly Interacting Massive Particles (WIMPs), have trouble explaining the results of direct and indirect experimental searches for dark matter particles as well as the astronomical observations of dark matter. This is why a wide variety of other solutions for the dark matter problem are being considered, and composite dark matter, made of dark atoms, is of special interest among them, challenging both experimental studies and theoretical research.

We invite investigators to contribute original research and review articles that seek to define the possible physical nature of composite dark matter and its constituents, to stimulate the experimental searches, and to suggest astrophysical tests for their effects. Potential topics include, but are not limited to:

• Particle models predicting new stable charged particles, new light bosons, and hidden photons related to new strict gauge U(1) symmetries
• Dark atoms bound by Coulomb forces and their interaction with matter
• Dark atoms bound by new light bosons
• Mixing of ordinary and hidden photons and millicharged particles
• Mirror and shadow matter in the Universe
• Dark atoms and their constituents and dark radiation in cosmology (their effects in Big Bang nucleosynthesis and large-scale structure formation, especially)
• Astrophysical effects of dark atoms and dark radiation
• Accelerator searches for constituents of dark atoms and dark radiation
• Nonaccelerator searches for dark atoms and dark radiation

Before submission authors should carefully read over the journal’s Author Guidelines, which are located at http://www.hindawi.com/journals/ahep/guidelines/. Prospective authors should submit an electronic copy of their complete manuscript through the journal Manuscript Tracking System at http://mts.hindawi.com/submit/journals/ahep/drad/ according to the following timetable: