"Understanding the Small-Scale Universe: Bridging Galaxy Formation and Cosmology"
MPE High-Energy Clusters & Cosmology Group Seminar
- Datum: 12.11.2025
- Uhrzeit: 11:00 - 12:00
- Vortragende(r): Leah Bigwood (University of Cambridge)
- Raum: HEG Meeting Room (1.3.27)
Abstract:
Uncertain modelling of baryonic feedback, how energy from active galactic nuclei and supernovae redistributes gas within and beyond halos, poses a major obstacle to testing the cosmological model with large-scale structure (LSS) probes that extend into the non-linear regime. Indeed, it represents the dominant source of uncertainty limiting the cosmological precision of weak lensing (WL). I will share work confronting this challenge: demonstrating that astrophysical models calibrated by gas probes can recover this loss of power, and providing evidence that the impact of baryonic feedback on the matter distribution is stronger than assumed in cosmological hydrodynamical simulations. Whether such strong feedback is physically plausible, and how a consensus model can be achieved to fully exploit the cosmological precision of upcoming LSS surveys, remain open questions. I will discuss a path forward: to use new, publicly available multi-wavelength survey data to transform our understanding of feedback processes and, in tandem, to develop a data-driven baryonic feedback model to fully realize the potential of next-generation weak lensing cosmology.
Uncertain modelling of baryonic feedback, how energy from active galactic nuclei and supernovae redistributes gas within and beyond halos, poses a major obstacle to testing the cosmological model with large-scale structure (LSS) probes that extend into the non-linear regime. Indeed, it represents the dominant source of uncertainty limiting the cosmological precision of weak lensing (WL). I will share work confronting this challenge: demonstrating that astrophysical models calibrated by gas probes can recover this loss of power, and providing evidence that the impact of baryonic feedback on the matter distribution is stronger than assumed in cosmological hydrodynamical simulations. Whether such strong feedback is physically plausible, and how a consensus model can be achieved to fully exploit the cosmological precision of upcoming LSS surveys, remain open questions. I will discuss a path forward: to use new, publicly available multi-wavelength survey data to transform our understanding of feedback processes and, in tandem, to develop a data-driven baryonic feedback model to fully realize the potential of next-generation weak lensing cosmology.