Speaker
Prof.
Daniel Grin
(Haverford College)
Description
Ultra-light axions arise generically in string compactifications and furnish an attractive possibility for dark matter and dark energy in the universe. I'll review the cosmological implications of ultra-light axions, covering phenomenology ranging from CMB power spectra to galaxy weak-lensing observations. After summarizing current constraints, I'll discuss the exciting axionic sensitivity of future surveys and experiments like the Large Synoptic Survey Telescope and CMB-SIV. I'll close by discussing a variety of open theoretical problems, ranging from an accurate treatment of the axion sound speed to a proper treatment of nonlinear collapse and structure formation in ultra-light axion scenarios.
Primary author
Prof.
Daniel Grin
(Haverford College)
