Wednesday Colloquium


"R Aquarii: direct insights into complex binary interactions with ALMA"

Joanna Mikołajewska (NCAC, Warsaw)

R Aqr is one of the closest symbiotic binaries composed of a white dwarf and Mira-type AGB star orbiting each other with ~44 yr period. It is one of the best studied symbiotic systems with the two binary components independently resolved by VLT and ALMA imaging. The binary is surrounded by very complex bipolar nebula with a spectacular jet outflow. I will review the properties of this system and present our first results on ALMA imaging of the molecular CO lines and the continuum distributions. In particupar, we have for the first time directly imaged the strong gravitational effects of the white dwarf secondary on the circumstellar wind leaving the AGB primary as well as the stream of material flowing from the Mira to the accretion disk around the white dwarf.


"Emergent de Sitter epoch of the quantum Cosmos"

Tomasz Pawłowski (Center for Theoretical Physics, Warsaw)

By using the regularization techniques of Loop Quantum Gravity we reexamine the quantum nature of the Big Bang in the framework of Loop Quantum Cosmology. The studies of the dynamics of a simple isotropic quantum Universe lead to a qualitative modification to the 'traditional' LQC bounce paradigm. Quantum gravity effects still lead to a quantum bounce connecting deterministically large classical Universes. However, the evolution features a large epoch of de Sitter Universe, with emergent cosmological constant of Planckian order, smoothly transiting into a flat expanding Universe.


"What was the last Noble Prizein physics given for?"

Czesław Radzewicz (Physics Department, Warsaw University)