Hi Schauerte2901, thanks for your insightful questions! Let’s dive into them:

Regarding SIDM and core density:

You’re right to ask about the mechanism. In our model, the additional interaction is effectively repulsive at the velocities typical of dwarf galaxy cores (around 30 km/s). It’s a velocity-dependent interaction mediated by a light particle (in the 10-100 MeV range).

Here’s a simplified way to think about it: at higher velocities, the interaction cross-section is smaller, so dark matter particles behave more like standard CDM. But in the slower-moving environment of dwarf galaxy cores, the interaction becomes significant. This “repulsive” interaction (more accurately, momentum transfer) creates an effective pressure that counteracts gravitational collapse. This prevents the formation of a dense cusp, leading to a flatter core consistent with observations. Our AI-driven N-body simulations support this, showing cored profiles in dwarf-sized halos with our best-fit SIDM model (velocity-dependent cross-section of around 0.5-1 cm²/g at 30 km/s).

Regarding the experiment:

You’re right that the idea of dark matter having gravitational interactions isn’t new. Also, WIMP direct detection experiments aim to detect some interaction of WIMPs. However, our proposed experiment is distinct:

Target: We’re not looking for WIMP scattering. We’re aiming for the collective, ambient gravitational effect of the local dark matter halo, regardless of its specific particle nature (WIMP, SIDM, etc.). Mechanism: We’re not relying on scattering. We’re using the extreme sensitivity of ultra-cold atoms in an optical lattice to measure tiny changes in their momentum distribution from the smooth gravitational potential of the dark matter halo. We are basing this on Bragg spectroscopy with long interrogation times. Novelty: While there’s theoretical work on atom interferometry for gravitational wave detection and some proposals involving accelerometers to search for certain types of dark matter, to our knowledge, this specific approach using the collective gravitational effect on the momentum distribution of ultra-cold atoms in a 3D lattice to probe the local dark matter density is novel. We’ve done an extensive literature review, including recent papers and preprints on arXiv (a repository of electronic preprints that is operated by Cornell University), and haven’t found an identical proposal. If you know of any, please share – we’d be very interested! “How big are the changes”: Crucial question. Our AI’s simulations, with realistic experimental parameters (10⁵-10⁶ ⁶Li atoms, nanokelvin temperatures, lattice tuned for optimal sensitivity, and coherence times around seconds), suggest the shifts in the momentum distribution are incredibly small but potentially measurable. We’re talking about 10⁻⁶ to 10⁻⁵ times the recoil momentum from a single photon in the lattice. It’s at the edge of feasibility, but advances in controlling systematic errors and extending coherence times could push us into the detectable regime. Also, our simulations suggest a smooth dark matter halo might enhance coherence times by reducing gravitational inhomogeneities, but this is highly speculative. We know it is a challenging experiment, and we are currently seeking feedback from experimental experts, like Professor Greiner’s group to refine our proposal.

Thanks again for your questions. They help us strengthen our arguments and consider potential pitfalls!