| Speaker: | Derek Inman (RIKEN iTHEMS) |
|---|---|
| Title: | Dark matter clustering in the radiation era due to attractive fifth forces |
| Date (JST): | Mon, Dec 15, 2025, 13:30 - 15:00 |
| Place: | Seminar Room B |
| Abstract: |
Standard cold dark matter typically collapses into nonlinear halos well into the matter era. While somewhat earlier halo formation can be achieved with enhanced primordial fluctuations, significant linear growth in the radiation era does not occur under gravity. Using Yukawa forces as an example, I will show how a dark sector with an attractive, long-range fifth force can enable exponential growth during this early period. I will then show examples of N-body simulations evolved with Newtonian and Yukawa forces, the latter of which can have fractional behavior, and compare the nonlinear density fields. Lastly, I will discuss possible fates for these collapsed objects as well as potential observational signatures. |
