September 2024 - ITP-quantumseminare

Monday's QIT seminar at 16:00 in E41.1.
by Ladina Hausmann 26 Sep '24

26 Sep '24

Hi all, Next week Antoine Coquet will talk about “Ruling out N-partite quantum causal networks as a complete theory of Nature”, see below for the abstract. The talk will take place on Monday at 16:00 in HIT E41.1. Best, Ladina *** Title: Ruling out N-partite quantum causal networks as a complete theory of Nature Abstract: A fundamental pursuit of physics is to understand correlations between events, or, in other words, causal relationships. Causal networks are a useful conceptual tool to study such causal structures. In this talk, we will: i) Give a brief introduction to the different types of correlations in Nature and to causal networks. ii) Introduce the class of proof techniques called "proofs by inflation" alongside a novel instance of such proofs which was developed in the course of the present work. iii) Use the above to prove that Nature’s correlations cannot be captured by quantum causal networks of N-partite quantum resources even when allowing for unlimited access to shared classical randomness.

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No QIT seminar this week
by Ladina Hausmann 20 Sep '24

20 Sep '24

Hi all, there is no QIT seminar planned for next week. Best, Ladina

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QIT seminar next week, new time for the semester
by Ladina Hausmann 13 Sep '24

13 Sep '24

Hi all, there is no QIT seminar planned for next week. We changed the seminar timeslot because the new semester will start next week. This semester it is Mondays at 16:00. Best, Ladina

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QIT seminars this week
by Ladina Hausmann 09 Sep '24

09 Sep '24

Hi all, this week we will have two seminars: - On Tuesday at 14:00 in HCI F2 Viktoria Kabel will talk about “Quantum Reference Frames & Subregions in Spacetime” - On Friday at 14:00 in HIT J52 Jakob Miller will talk about “Improving the performance of two-source randomness extractors against quantum side-information” see below for the abstracts. Best, Ladina *** Title: Quantum Reference Frames & Subregions in Spacetime Abstract: In this talk, I will dive into the connection between quantum reference frames and the study of subregions in general relativity. The first part of the talk will motivate the concept of edge modes - additional degrees of freedom that arise at the boundary of subregions in gauge theory and gravity - and provide a gentle introduction to the mathematical tools used to study them. In the second part of the talk, these ideas will be applied to subregions in linearised general relativity. Here, edge modes arise naturally at the boundary of spacetime subregions and can be interpreted as reference frames for the diffeomorphism group. When quantising the theory, we must account for these degrees of freedom, which gives rise to quantum reference frames at the boundary of spacetime. *** Title: Improving the performance of two-source randomness extractors against quantum side-information Abstract: In most (quantum) cryptographic protocols perfect randomness is an essential resource that is typically taken for granted, although the existence of real-world sources of perfect randomness is questionable. Fortunately, randomness extractors can bridge the gap between theory and implementation. Illustrated by the above application, in this talk we introduce two-source extractors against quantum/classical side-information. In particular, we discuss side-information in the product and Markov model. We derive a new XOR lemma that allows for significant improvements of the achievable output length of the extractors first introduced by Dodis et al. and that promises further improvements for a wide range of two-source extractors.

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No seminar this week
by Ladina Hausmann 03 Sep '24

03 Sep '24

Hi all, there is no QIT seminar planned for this week. Best, Ladina

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