Speaker
Alex Kim
(Lawrence Berkeley National Laboratory)
Description
Precise measurement of the Hubble constant depends on anchoring the cosmic distance ladder with direct stellar measurements. I propose a precision intensity interferometry program to measure red-clump star angular sizes, providing a new observational foundation for distance-ladder calibration. I also present pathways to detect spacetime foam—a quantum-gravity prediction—through high-precision astrophysics: via spectroscopic signatures in temporal coherence from GRBs and the CMB (first-order coherence), and through imaging observations revealing Siegert relation violations (HBT). Together, these proposed observational programs probe both cosmic expansion and the fundamental structure of spacetime.
Primary author
Alex Kim
(Lawrence Berkeley National Laboratory)
