Dark Stars: The first phase of stellar evolution in the universe may be powered by Dark matter heating rather than by nuclear fusion. WIMPs, which can be their own antiparticles, collect inside the stars and annihilate to produce a heat source that can power the star. A new stellar phase results, Dark Stars, powered by dark matter annihilation as long as there is dark matter fuel, for millions to billions of years.
Open Questions: Many outstanding questions remain: In the scenario where the Dark Star captures more and more matter, how big does it get? How can we observe dark stars: signatures include direct observation (is this possible with JWST?), neutrinos from the annihilation (contribution to the background), elemental abundances. What is the effect of dark Stars on reionization? Dark Stars in any case give rise to very large Population III stars, 1000 solar masses or larger: can these stars produce seeds for the large black holes seen in galaxies today, as quasars at high redshift. Can they power gamma ray bursts at high redshift? What is the detailed stellar evolution of the Dark Star? What if axions are the dark matter?