Cosmology with Type Ia SN after the Nobel prize: level-up or game-over?

by Prof. Ariel Goobar (Fysikum, University of Stockholm)

Tuesday 5 Jun 2012, 13:15 → 14:15 Europe/Stockholm

FA32

The discovery of the accelerated expansion using Type Ia supernovae completely changed our understanding of what the Universe is made of. We now know that dark energy, the least theoretically understood energy form, is the dominant component. All attempts to find observational deviations from Einstein's cosmological constant have been fruitless -so far. Given the current constraints, future efforts to study the nature of dark energy will be limited by systematic uncertainties. Distance measurements with Type Ia SNe remain a very competitive cosmological probe, provided we can address some of the outstanding astrophysical concerns: extinction by dust and brightness evolution. I plan to discuss ongoing efforts at OKC to break the degeneracy between some of the potential sources of dimming/reddening of SNe Ia: interstellar dust, circumstellar dust and intrinsic color variations. Furthermore, I will present ideas on how to exploit gravitational lensing of supernovae by galaxy clusters to do high S/N spectroscopic studies of z~1.5 in the near-IR, an exciting path to explore a potential change in SNIa properties with cosmic time.