Shedding light on the small-scale crisis with CMB spectral distortions

  title={Shedding light on the small-scale crisis with CMB spectral distortions},
  author={Tomohiro Nakama and Jens Chluba and Marc Kamionkowski},
  journal={Physical Review D},
The small-scale crisis, discrepancies between observations and N-body simulations, may imply suppressed matter fluctuations on subgalactic distance scales. Such a suppression could be caused by some early-universe mechanism (e.g., broken scale invariance during inflation), leading to a modification of the primordial power spectrum at the onset of the radiation-domination era. Alternatively, it may be due to nontrivial dark-matter properties (e.g., new dark-matter interactions or warm dark… Expand

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