February 6, 2025, Thursday, 10.00
Short Paper: J. Finkelstein: Definition of decoherence link
Longer Paper: C. Riedel, W. Zurek, M. Zwolak: Objective past of a quantum universe: Redundant records of consistent histories link
By Tibor Rakovszky
February 13, 2025, Thursday, 8.30
Paper: C. Riedel, W. Zurek, M. Zwolak: Objective past of a quantum universe: Redundant records of consistent histories link
Short comment: L. Diósi: Anomalies of Weakened Decoherence Criteria for Quantum Histories link
By Tibor Rakovszky
February 20, 2025, Thursday, 8.30
Paper: P. Strasberg, J. Schindler: First Principles Numerical Demonstration of Emergent Decoherent Histories link
By Daniel Varjas
February 27, 2025, Thursday, 8.30
Paper: P. Strasberg, J. Schindler: First Principles Numerical Demonstration of Emergent Decoherent Histories link
By Daniel Varjas
March 6, 2025, Thursday, 8.30
Paper: part of K. Hornberger: Introduction to decoherence theory link
Notes: Pointer states link
By Győző Egri
Paper: P. Strasberg, J. Schindler: Shearing Off the Tree: Emerging Branch Structure and Born’s Rule in an Equilibrated Multiverse link
By János Asbóth
March 13, 2025, Thursday, 8.30
Paper: N. Loizeau, F. Morone and D. Sels: Unveiling Order from Chaos by approximate 2-localization of random matrices link
By István Csépányi
March 20, 2025, Thursday, 8.30
Paper: N. Loizeau, F. Morone and D. Sels: Quantum mereology and subsystems from the spectrum link
By Márton Kormos
March 27, 2025, Thursday, 8.30
Paper: J. Wang, P. Strasberg: Decoherence of Histories: Chaotic Versus Integrable Systems link
By Solomon Brhanu Samuel
April 3, 2025, Thursday, 8.30
Title: Decoherent histories and a quantitative understanding of the many worlds interpretation
Abstract: This talk overviews and advertises the decoherent histories framework as a useful tool to make sense of a unitarily evolving Universe. In particular, observers can find records about past events if and only if the associated quantum histories are decoherent. I then review three recent quantitative insights about decoherent histories. First, I show that decoherence arises exponentially fast as a function of system size for slow and coarse observables. Second, this result only holds for chaotic systems, whereas integrable systems show a very different scaling. Third, I give preliminary insights into the structure of decoherence that arises for very long histories.
Discussion of papers link, link and link
By Philipp Strasberg (online)
April 10, 2025, Thursday, 8.30
Paper: L. Vaidman: Role of potentials in the Aharonov-Bohm effect link
Notes: Aharonov-Bohm link
By Győző Egri
April 17, 2025, Thursday, 8.30
Paper: P. Pearle, A. Rizzi: Quantized vector potential and alternative views of the magnetic Aharonov-Bohm phase shift link
Original idea: L. Vaidman: Role of potentials in the Aharonov-Bohm effect link
Notes: Aharonov-Bohm link
By Győző Egri
April 24, 2025, Thursday, 8.30
Paper: I. Duque, P. Strasberg: Toy Model Challenging Prevailing Definitions of Classicality link
By János Asbóth
May 15, 2025, Thursday, 8.30
Title: Locality and subsystems from the spectrum
Abstract: The minimal ingredients to describe a quantum system are a Hamiltonian, an initial state, and a preferred tensor product structure that encodes a decomposition into subsystems. I will discuss a top-down approach in which the decomposition into subsystems emerge from the spectrum of the whole system. This approach has been referred to as quantum mereology. In practice, it is interesting to understand whether a given Hamiltonian is compatible with some given tensor product structure. Addressing this question allows us to suggest a possible mechanism for the emergence of locality and subsystems from quantum mechanics itself.
Discussion of papers link and link
By Nicolas Loizeau (online)
May 22, 2025, Thursday, 8.30
Paper: Adil et al: A Search for Classical Subsystems in Quantum Worlds link
By Máté Lencsés
May 29, 2025, Thursday, 8.30
Title: Time evolution of subsystems, initial system-environment correlations
Paper: part of Breuer-Petruccione: The theory of open quantum systems, chapter 9 link
Notes: Time evolution of subsystems link
By Győző Egri