Physics Colloquium: Twins, Composites and Dark Relics

Abstract:

The LHC has found no evidence of physics beyond the Standard Model, and the hierarchy problem of the Higgs is so far unresolved. Standard solutions to the hierarchy problem, such as supersymmetry and "composite Higgs" models, require new "partner" particles to cancel the quadratically divergent loop contribution to the mass of the Higgs. These new particles have not been discovered at the LHC putting severe constraints on these models. In this colloquium I will describe the "neutral naturalness" approach via a first realization as a "composite twin Higgs model". The novelty in this approach is that the "partners" can be neutral under the electro-weak and the strong interactions and therefore cannot be discovered at the LHC. I will then explore different directions for probing this idea - direct collider searches, Higgs and electroweak physics, cosmological and astrophysical probes, while exploring previously unexplored theoretical possibilities in composite Higgs.

Event Organizer: Prof. Alexander Palevsky