ELFT HÍRADÓ

[Dr.Pályi András <palyi.andras AT ttk.bme.hu>]

Dear Colleagues,

This is to advertise the following talk of Tamás Kriváchy on "Topologically 
Robust Quantum Network Nonlocality”.

Time: Jan 20, Monday, 14:15
Location: seminar room of the Department of Theoretical Physics, BME F 
building, stairway III, ground floor.

Tamás Kriváchy (ICFO Barcelona, https://krivachy.xyz/)
Topologically Robust Quantum Network Nonlocality
https://arxiv.org/abs/2406.09510

Abstract: "We discuss quantum network Bell nonlocality in a setting where the 
network structure is not fully known. More concretely, an honest user may 
trust their local network topology, but not the structure of the rest of the 
network, involving distant (and potentially dishonest) parties. We 
demonstrate that quantum network nonlocality can still be demonstrated in 
such a setting, hence exhibiting topological robustness. Specifically, we 
present quantum distributions obtained from a simple network that cannot be 
reproduced by classical models, even when the latter are based on more 
powerful networks. In particular, we show that in a large ring network, the 
knowledge of only a small part of the network structure (involving only 2 or 
3 neighbouring parties) is enough to guarantee nonlocality over the entire 
network. This shows that quantum network nonlocality can be extremely robust 
to changes in the network topology. Moreover, we demonstrate that 
applications of quantum nonlocality, such as the black-box certification of 
randomness and entanglement, are also possible in such a setting.”

Guests are welcome.

Best regards,
Andras Palyi