arXiv subjects

I. A. Paulson

Publications and source records attributed to I. A. Paulson.

4 recordsLinked to original sources

arXiv2026

Probing For Non-Gravitational Galactic-Range Dark Matter Interactions

Dark matter remains a mystery in fundamental physics. The only evidence for dark matter's existence is from gravitational interactions. We operated a precision torsion balance experiment to search for non-gravitational, galactic-range interactions between ordinary matter in our lab and the Milky Way's dark matter. We find no evidence of such interaction and set upper bounds on its strength that are a fourfold improvement over previous limits. These results constrain a variety of dark matter theories and test the equivalence principle towards dark matter.

gr-qc↗

arXiv2026

An Improved Torsion Balance Test of the Equivalence Principle Towards the Sun

We search for violations of the Equivalence Principle towards the Sun using a rotating torsion balance apparatus. We set 95\%-confidence limits on violations with beryllium and aluminum test bodies of $η_{\odot, Be-Al} \leq 2.1 \times 10^{-13}$. These results are a factor of four improvement of previously reported results towards the Sun and a $\sim20\%$ improvement on previous torsion balance tests regardless of source.

gr-qc↗

arXiv2025

A Search for Ultra-Light Vector Dark Matter with a Rotating Torsion Balance

We search for ultra-light vector dark matter interacting with a rotating torsion balance with a baryon minus lepton number composition dipole. Our search spans candidate masses in the ultra-low mass range from 1.3~$\times10^{-22}$ to 1.9~$\times10^{-18}$ eV. We set limits on the coupling strength to baryon minus lepton number for each dark matter candidate reaching a peak sensitivity of $g_{B-L} \leq 9 \times 10^{-26}$.

hep-ex↗

arXiv2024

Test of the Equivalence Principle for Superconductors

We searched for violations of the weak equivalence principle using a cryogenic torsion balance with a pendulum comprised of superconducting niobium and copper. We constrain the Eötvös parameter with 95%-confidence to $η_{\text{Nb*-Cu}}~\leq~2.0\times10^{-9}$ and $η_{\text{CP-ee}}\leq9.2\times10^{-4}$ for superconducting niobium and Cooper pairs, respectively.

gr-qc↗