Degradation of the resource state in the deterministic port-based teleportation scheme

Date: Friday, April 8, 2022
Time: 12:15
Host: IFTIA Seminar (room 361)
Passcode: 78pA05
Speaker: Piotr Kopszak Abstract Port-based teleportation (PBT) is a quantum teleportation protocol, in which the parties exploit joint measurements performed on $N$ shared $d$-dimensional maximally entangled pairs (the resource) and the state to be teleported, with the addition of the one-way classical communication. The lack of correction in the last step is an essential feature […]

Physics and Metaphysics of Wigner’s Friends

Date: Monday, April 11, 2022
Time: 14:15
Host: Quantum Chaos and Quantum Information (Jagiellonian University)
Passcode: subspace
Speaker:  Marcin Markiewicz ( University of Gdańsk ) Abstract Recently there appeared many works on modified Wigner's Friend paradoxes, which suggest that quantum theory cannot consistently describe the scenario with many observers. In this presentation I will show an alternative approach to this problem, which indicates that the paradoxes are in fact apparent, and the […]

Quantum Complexity of Experiments

Date: Wednesday, April 6, 2022
Time: 16:00
Host: Team-Net Quantum Computing Colloquium
Passcode: teamnet
Speaker: Jordan Cotler (Harvard University) Abstract We introduce a theoretical framework to study experimental physics using quantum complexity theory. This allows us to address: what is the computational complexity of an experiment? For several 'model' experiments, we prove that there is an exponential savings in resources if the experimentalist can entangle apparatuses with experimental samples. […]

Quantum thermodynamics of coronal heating

Date: Wednesday, April 6, 2022
Time: 14:15
Host: ICTQT Seminar (room 45)
Speaker: Alejandro Jenkins (ICTQT) Abstract The question of how heat is persistently transported from the Sun's photosphere (at about 6,000 K) to the much hotter corona (at about 10^6 K) is one of the great open puzzles in astrophysics. Using the quantum Markovian master equation, we show that convection in the stellar photosphere generates plasma […]

Heat release to and entropy production in the electromagnetic and the (linear) gravitational vacua

Date: Monday, April 4, 2022
Time: 12:00
Host: ICTQT Seminar (room 45)
Speaker: Erik Aurell (KTH Royal Institute of Technology, Stockholm) Abstract A well-studied model in open quantum system theory is a system interacting with a thermal bath of harmonic oscillators at finite temperature. This provides a quantum mechanical model of a classical resistive element in a circuit, and includes as famous examples the Caldeira-Leggett theory of […]

Operational Quantum Average-Case Distance

Date: Monday, March 28, 2022
Time: 14:15
Host: Quantum Chaos and Quantum Information (Jagiellonian University)
Passcode: subspace
Speaker: Filip Maciejewski (CFT PAN Warszawa) Abstract We introduce operational distance measures between quantum states, measurements, and channels based on their average-case distinguishability. To this end, we analyze the average Total Variation Distance (TVD) between statistics of quantum protocols in which quantum objects are intertwined with random circuits and subsequently measured in a computational basis. […]

Examples of standing gravitational waves in general relativity

Date: Friday, March 25, 2022
Time: 11:00
Host: ICTQT room 42
Speaker: Sebastian Szybka  (Jagiellonian University) Abstract Standing waves are a quite common phenomenon in physics.They are well understood in linear theories. In Einstein's gravity, which is a nonlinear theory, the lack of superposition principle complicates studies. I will present exact solutions to Einstein equations that correspond to standing gravitational waves. They provide useful toy-models that […]

Physics and Metaphysics of Wigner’s Friends

Date: Friday, March 25, 2022
Time: 12:15
Host: IFTIA Seminar
Passcode: yf5Ze2
Speaker: Marcin Markiewicz  (ICTQT) Abstract Recently there appeared many works on modified Wigner's Friend paradoxes, which suggest that quantum theory cannot consistently describe the scenario with many observers. In this presentation I will show an alternative approach to this problem, which indicates that the paradoxes are in fact apparent, and the source of confusion is […]