Talk abstract details

Primordial black holes as dark matter
A. S. Majumdar


We present a scenario in which primordial black holes in higher dimensional theories can survive up to present times as components of dark matter in the universe. We explicitly consider two different cosmological models, viz., a braneworld model, and a generalized Jordan-Brans-Dicke model, to show that accretion of radiation is an effective process in the early universe, which dominates over the black hole evaporation rate. Thus these primordial black holes can be long-lived and impact various cosmological epochs through their density and evaporation products. We further suggest a possible mechanism for their observational signature through strong gravitational lensing.
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2. Interacting black holes on the brane: the seeding of binaries, A. S. Majumdar, A. Mehta and J. M. Luck, Phys. Lett B607,219(2005).
3. Braneworld black holes in cosmology and astrophysics, A. S. Majumdar and N. Mukherjee, --- {invited review article}, Int. J. Mod. Phys. D14, 1095 (2005).
4. Particle motion and gravitational lensing in the metric of a dilaton black hole in a de Sitter universe, N. Mukherjee, A. S. Majumdar, Gen. Relativ. Grav. 39, 583 (2007).
5. Evolution of primordial black holes in Jordan-Brans-Dicke cosmology, A. S. Majumdar, D. Gangopadhyay and L. P. Singh, Mon. Not. Roy. Astron. Soc. 385, 1467 (2008).