Astrophys. J. doi:10.1086/592037 (2008)

If the remnants of the first stars were to be found, they should be in small galaxy groups — relatively common structures. Calculations by Michele Trenti, now of the University of Colorado at Boulder, and his colleagues also suggest that the earliest, brightest quasars evolved to become part of galactic groups of medium brightness.

This is at odds with current theory, which puts remnants of the first stars — born when the Universe was just 65 million years old — in the largest observable clusters in the present-day Universe. Similarly, current theory places the remnants of the brightest quasars from about 1 billion years after the Big Bang in the largest clusters.