Departmental Colloquium
Pawel Horodecki
Gdańsk University of Technology
Quantum correlations: from foundations to security against post-quantum eavesdropper
Abstract: Quantum mechanics allows quantum correlations – also called quantum entanglement – that are
stronger than all the correlations we know from our daily lives. Their enigma has already troubled
fathers of Quantum Mechanics. Einstein's ingenious skepticism about this theory gave rise to the
fundamental philosophical question - formalized mathematically by John Bell - about the objective
existence of properties of quantum particles before measurement.
We shall discuss the related Bell inequalities tests from the perspective of randomness and stress
that while quantum mechanical statistics look completely random, it may allow for a contribution of
determinism, if we look at them from the perspective of possible future physical theories. This rises
an interesting problem of certification of randomness and cryptographic security in hypothetical
situations where eavesdropper has a post-quantum power.
The two most natural post-quantum frameworks are the ones of no-signaling boxes and no-
signaling assamblages. We discuss quantum correlations from the perspectives of the two
frameworks. This includes on the one hand some no-go theorems and on the other hand some
positive results concerning randomness amplification and generation of secure bits.
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Please reach out to Shmuel Friedland if you want to join the speaker for lunch or dinner, or have a meeting during their visit.
Friday October 6, 2023 at 3:00 PM in 636 SEO