Caldwell is a Royal Society University Research Fellow establishing the Molecular Quantum Matter Lab at UCL. Research directions: (1) Precision molecular spectroscopy for dark matter and fifth-force searches — measuring isotope shifts in molecular systems to test Standard Model predictions and probe new forces between neutrons and electrons; (2) Quantum control of molecules in external fields — laser cooling, Stark deceleration, and magneto-optical trapping of polar molecules; (3) Molecular beam spectroscopy with frequency comb referencing for ultra-high-precision lineshape measurements. The lab aims to build the most precise molecular spectrometer for BSM physics searches. Actively building the lab and seeking motivated students/postdocs.