Cosmological direct detection of dark energy: non-linear structure formation signatures of dark energy scattering with visible matter

Understand

We consider the recently proposed possibility that dark energy (DE) and baryons may scatter through a pure momentum exchange process, leaving the background evolution unaffected.

• Earlier work has shown that, even for barn-scale cross-sections, the imprints of this scattering process on linear cosmological observables is too tiny to be observed.
• We therefore turn our attention to non-linear scales, and for the first time investigate the signatures of DE-baryon scattering on the non-linear formation of cosmic structures, by running a suite of large N-body simulations.
• The observables we extract include the non-linear matter power spectrum, halo mass function, and density and baryon fraction profiles of halos.