Convex-roof entanglement measures of density matrices block diagonal in disjoint subspaces for the study of thermal states

Date: poniedziałek, 25 kwietnia, 2022
Time: 14:15
Host: Quantum Chaos and Quantum Information (Jagiellonian University)
Passcode: subspace
Speaker:  Katarzyna Roszak (Institute of Physics, Czech Academy of Sciences) Abstract We provide a proof that entanglement of any density matrix which block diagonal in subspaces which are disjoint in terms of the Hilbert space of one of the two potentially entangled subsystems can simply be calculated as the weighted average of entanglement present within […]

Quantum effects in biological systems

Date: piątek, 22 kwietnia, 2022
Time: 12:15
Host: IFTIA Seminar (room 361)
Passcode: 78pA05
Speaker: Kai Sheng Lee Abstract Quantum mechanics is at its hearts the study of nature at the fundamental level of atoms and subatomic particles. Made up of these same atoms and subatomic particles, biological systems are also expected to follow quantum mechanics to some extent. The most well-known example (and still debated) is in magnetoreception, […]

Genuine multipartite entanglement and nonlocality in pair-entangled network states

Date: środa, 20 kwietnia, 2022
Time: 15:15
Host: Quantum Information and Quantum Computing Working Group (CTP PAS)
Passcode: nisq
Speaker: Julio de Vicente (Universidad Carlos III de Madrid) Abstract The study of entanglement and nonlocality in multipartite quantum states plays a major role in quantum information theory and genuine multipartite entanglement (GME) and nonlocality (GMNL) signal some of its strongest forms for applications. However, their characterization for general (mixed) states is a highly nontrivial […]

Quantum reference frames: towards a quantum description of space and time

Date: środa, 13 kwietnia, 2022
Time: 12:30
Host: Center for Theoretical Physics Colloquium
Passcode: 134595
Speaker: Flaminia Giacomini Abstract In physics, observations are typically made with respect to a frame of reference. Although reference frames are usually not considered as degrees of freedom, in practical situations it is a physical system that constitutes a reference frame. Can a quantum system be considered as a reference frame and, if so, which […]

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

Date: piątek, 8 kwietnia, 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: poniedziałek, 11 kwietnia, 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: środa, 6 kwietnia, 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: środa, 6 kwietnia, 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: poniedziałek, 4 kwietnia, 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 […]