Wednesday Colloquium



19.02.2020

"Quantum communication in space"

Piotr Kolenderski (Uniwersytet Mikołaja Kopernika, Toruń)

Quantum communication offers a selection of methods for absolutely secure exchange of information. There are two particular links which are used in practice: fibers and free space. The latter implemented using satellites is more challenging, but offers substantially longer ranges. During my talk I will present two projects running in our lab at Nicolaus Copernicus University, which are related to satellite based quantum communication. The first one aims in building a ground station for a satellite receiver link. The second one is a joint effort with Syderal Polska, where the goal is to build a satellite-grade polarization entanglement controller.


26.02.2020

"Echoes from the sky: X-ray reverberation around BHs"

Barbara de Marco (CAMK, Warsaw)

What is the geometry of the accretion flow around accreting black holes (BH), and how does it evolve with the accretion state of the source? Time delays associated with the reprocessed signal from gas orbiting the BH allow us to map the innermost regions of accreting-BH systems. This technique, called X-ray reverberation, is shedding some light on these outstanding questions. I will be discussing the state-of-the-art in this field.