Cosmology after Phantom Crossing by Horndeski Gravity
Eric V. Linder

TL;DR
This paper explores how shift symmetric Horndeski gravity models can explain the crossing of the dark energy equation of state over the phantom divide, emphasizing the impact on cosmic structure growth and lensing.
Contribution
It identifies three main pathways within shift symmetric Horndeski gravity that allow for phantom crossing, analyzing their implications for cosmic expansion and structure formation.
Findings
Multiple models can realize phantom crossing with distinct kinetic structures.
Implications for growth of large-scale structure and lensing are discussed.
The behavior of the equation of state after crossing is characterized.
Abstract
One possible way to explain the observed effective dark energy equation of state crossing (the phantom divide) is through modified gravity. A key point is to not view the expansion history in isolation but to take into account the other gravitational impacts on growth of large scale structure, lensing, etc. Within shift symmetric Horndeski gravity this implies three main paths for the late time cosmic expansion. All require unusual kinetic structure and we analyze their various implications for how should behave after phantom crossing.
Peer Reviews
No public reviews on file for this paper yet. If you reviewed it on a platform where reviews are public (OpenReview, ICLR, NeurIPS, ICML), you can paste yours below so the community can read it here.
Videos
No videos yet. Explain this paper in a talk, walkthrough, or lecture? Add one.
Taxonomy
TopicsCosmology and Gravitation Theories · Galaxies: Formation, Evolution, Phenomena · Dark Matter and Cosmic Phenomena
