## "Is axion dark matter described by a classical scalar field?"Elisa Todarello
, University of Florida
[Host: Peter Arnold]
ABSTRACT:
Axion dark matter has the unique property of having extremely high quantum occupancy. This may lead to think that axion dark matter can be described in terms of a classical field. The usual equations for the linear growth of density perturbations in the cold dark matter fluid can be obtained from the classical description of a self-gravitating scalar field in the non-relativistic regime, with differences appearing only on scales smaller than a critical length. However, axion dark matter is expected to thermalize through gravitational self-interactions and to form a Bose-Einstein condensate. I will argue that the classical field approximation is in general not valid for thermalizing quantum fields, even in the large occupancy regime, and discuss the different evolution of a homogeneous condensate in classical and quantum field theory. |
High Energy Physics SeminarWednesday, October 4, 2017 3:30 PM Physics Building, Room 204 Note special room. |

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