Gravitational absorption lines

  title={Gravitational absorption lines},
  author={Andrea Palessandro and M. Sloth},
  journal={Physical Review D},
We consider the gravitational analogue of Lyman-alpha absorption lines in astronomical spectroscopy. If Einstein gravity with minimally coupled matter is valid up to the Planck scale, quantum bound states absorb gravitons of a specific frequency with Planckian cross section, $\sigma_{\text{abs}} \approx l_p^2$. Consequently, one can show that gravitational absorption by bound states is inefficient in ordinary gravity. If observed, gravitational absorption lines would therefore constitute a… Expand

Figures from this paper

Paper Mentions