Abstract

Understanding the formation and growth of supermassive black holes (BHs) is subject to intense research. BHs of more than 1 billion solar masses already powered luminous quasars when the Universe was only 0.8 Gyr old, suggesting that they had to grow from seed BHs at z> 7 and grow very rapidly. The models proposed for the formation of BH seeds include the remnants of the first population of massive (Population III) stars, the direct collapse of primordial gas, or mergers in dense stellar clusters. Observationally, the detection of such high-redshift BHs constitutes a serious challenge.However, the leftovers of those seed BHs that did not grow into supermassive BHs can be found in the local Universe as intermediate-mass BHs of less than 1 million solar masses in e.g., dwarf galaxies, globular clusters, or ultraluminous X-ray sources, and can provide direct constraints on the seed BH formation models at z> 7. Intermediate-mass BHs also provide ample ground for studies of the low-mass end of the BH mass function, the behavior of the BH-galaxy scaling relations at low BH masses, the tidal disruption of stars, or the detection of gravitational waves.This workshop aims at assembling theorists and observers to review the current status of models and observations and discuss the prospects of up-coming observatories for detecting seed BHs and discriminating between competing theories. The format of the workshop allows ample time for presentations and for interactive work among the participants.