Self-interacting and asymmetric dark matter – TheIntricateDark

Non-perturbative effects in quantum field theory.
Boltzmann equations describing the evolution of dark matter in the early universe.
Thermodynamics of the early universe.

Computed various radiative bound-state formation cross-sections.
Showed how indirect detection constraints strengthen when the formation and decay of unstable bound states is considered.
Placed strong constraints on symmetric self-interacting dark matter models.
Proposed asymmetric dark matter as a viable framework for self-interacting dark matter.
Showed that the Standard Model Higgs can mediate a long-range interaction between particles of few hundred GeV or heavier (Higgs enhancement).

The Higgs as mediator of long-range forces

Future prospect: Investigate further the long-range effect of the Higgs in a variety of dark matter models.

arXiv:1611.01394,
arXiv:1612.07295,
arXiv:1703.00478,
arXiv:1711.03552,
arXiv:1712.07489

Dark matter is paramount for understanding our universe. It is five times more abundant than ordinary matter, and it is responsible for creating the potential wells in which ordinary matter fell to form galaxies and stars. However, the fundamental nature of dark matter remains unknown. Discovering the particles it consists of and understanding their interactions would therefore also mean unravelling new fundamental laws of nature. The importance of dark matter for particle physics, cosmology and astrophysics has placed it in the forefront of the experimental and theoretical research in these fields.

Current observations suggest that the particle-physics dynamics of dark matter may be quite rich, and rather different from long-held expectations: The comparable amounts of dark and ordinary matter indicate that the dark matter density may be due to an excess of dark particles over dark antiparticles, an asymmetry, dynamically related to the ordinary matter-antimatter asymmetry. Moreover, the observed galactic structure can be explained better if dark matter possesses sizeable self-interactions rather than being collisionless.

In recent work, I explored the high-energy physics that could relate the dark and ordinary matter abundances, within the asymmetric dark matter scenario. I constructed detailed particle-physics models, and demonstrated that they provide a very suitable host for self-interacting dark matter. Furthermore, I showcased that the complicated cosmology which self-interacting dark matter typically implies, has important consequences for its phenomenology today.

The proposed project aims to fully develop this new paradigm of self-interacting asymmetric dark matter along two paths. First, I plan to compute in a comprehensive way the cosmologies of models of dark matter with long-range self-interactions. Second, using this as input, I aim to work out consistently the direct and indirect detection signatures of these theories. I expect the results to inform and guide experimental searches and numerical studies of dark matter.