Yong Sheng Yap is a PhD student at the University of Cambridge. He will visit the Argelander Institute of Astronomy as a guest scientist, and give the following talk on Tuesday, October 20 2026 at 14:00.
Title: Protected Pathways to Primordial Physics
Speaker: Yong Sheng Yap, University of Cambridge
Location: Room 0.02, MPIfR (Auf dem Hügel 69, 53121 Bonn)
Abstract: Primordial non-Gaussianity (PNG) offers a unique window into the physics of the early Universe. For the past few decades, observations of the Cosmic Microwave Background (CMB) have provided the most stringent constraints on PNGs. Looking ahead, future constraints from large-scale structure (LSS) would become increasingly competent as we continue to deplete the measurable modes in the CMB. However, extracting PNG signatures from LSS observables become challenging due to effects of gravitational nonlinearities. One way forward is to identify protected observables: features of primordial physics that cannot by mimicked by conventional late-time processes. In this talk, I will discuss two new examples of such observables, one of which is a scale-dependent bias that is only present in galaxy samples selected upon their internal properties and vanishes in a complete sample. Second of which incorporates density-density-momentum bispectra into the ensemble of statistics that are sensitive to parity violation, allowing parity-violation to be constrained using only 3-point statistics. Together, these results open new avenues for constraining PNGs with upcoming surveys.
For the Zoom meeting link, please contact the Dynaverse Office.
Photo Credit: TNG Simulations
