Past Quantum Lunches

10 Mar. 2021, 12:00-13:00

ON-LINE QLunch: Roger Colbeck

Speaker: Roger Colbeck from the University of York

3 Mar. 2021, 12:00-13:00

ON-LINE QLunch: Asbjørn Bækgaard Lauritsen

Speaker: Asbjørn Bækgaard Lauritsen, IST Austria

24 Feb. 2021, 12:00-13:00

ON-LINE QLunch: Christoph Hirche

Speaker: Christoph Hirche from QMATH

27 Jan. 2021, 12:00-13:00

ON-LINE QLunch: Johannes Meyer

Speaker: Johannes Meyer, Freie Universität Berlin

13 Jan. 2021, 12:00-13:00

ON-LINE QLunch: Ian Jauslin

Speaker: Ian Jauslin from Princeton University

16 Dec. 2020, 12:00-13:00

ON-LINE QLunch: Fault-tolerant coding for quantum communication

Speaker: Alexander Müller-Hermes from Université de Lyon I

18 Nov. 2020, 12:00-13:00

ON-LINE QLunch: Daniel Stilck and Christoph Hirche

Speakers: Daniel Stilck and Christoph Hirche from QMATH

4 Nov. 2020, 12:00-13:00

ON-LINE QLunch: Morten Kjaergaard

Speaker: Morten Kjaergaard from NBI

28 Oct. 2020, 12:00-13:00

ON-LINE QLunch: Alvin Moon

Speaker: Alvin Moon from QMATH

11 Sept. 2020, 13:00-14:00

QLunch:Bergfinnur Durhuus

Speaker: Bergfinnur Durhuus from QMATH

31 Aug. 2020, 15:00-16:00

QMATH Seminar: Jens Hoppe

Speaker: Jens Hoppe

26 Aug. 2020, 12:00-13:00

QLunch: Sigurd Storgaard

Speaker: Sigurd Storgaard

17 June 2020, 12:00-13:00

ON-LINE QLunch: Thor Gabelgaard Nielsen

Speaker: Thor Gabelgaard Nielsen

3 June 2020, 12:00-13:00

ON-LINE QLunch: Tommaso Guaita

Speaker: Tommaso Guaita, The Max Planck Institute of Quantum Optics

6 May 2020, 12:00-13:00

ON-LINE QLunch: Péter Vrana

Speaker: Péter Vrana, Budapest University of Technology and Economics

29 Apr. 2020, 12:00-13:00

ON-LINE QLunch: Niels Benedikter

Speaker: Niels Benedikter

22 Apr. 2020, 12:00-13:00

ON-LINE QLunch: Torben Krüger

Speaker: Torben Krüger

15 Apr. 2020, 12:00-13:00

ON-LINE QLunch: Jan Philip Solovej

Speaker: Jan Philip Solovej

8 Apr. 2020, 12:00-13:00

CANCELLED ON-LINE QLunch: Jørgen Rasmussen

Speaker: Jørgen Rasmussen, University of Queensland

1 Apr. 2020, 12:00-13:00

ON-LINE QLunch: Andreas Bluhm

Speaker: Andreas Bluhm

25 Mar. 2020, 12:00-13:00

ON-LINE Lunch: Jitendra Prakash

Speaker: Jitendra Prakash

11 Mar. 2020, 12:00-13:00

QLunch: MIP* = RE (video)

Speaker: Henry Yuen

12 Feb. 2020, 12:00-13:00

QLunch with Cambyse Rouzé

Approximate tensorization of the relative entropy for noncommuting conditional expectations

5 Feb. 2020, 12:00-13:00

QLunch with Yinan Li

Title: The Haemers Bound of Graphs and Noncommutative Graphs, and Quantum Shannon Capacities

22 Jan. 2020, 12:00-13:00

QLunch: Quantum Photonics for AI and AI for Quantum Photonics

Speaker: Jacques Carolan from NBI

8 Jan. 2020, 12:00-13:00

QLunch: Tensor network representations from the geometry of entangled states

Speaker: Matthias Christandl from QMATH

18 Dec. 2019, 12:00-13:00

QLunch: Distributed quantum sensing in a CV network

Speaker: Johannes Borregaard from QMATH

20 Nov. 2019, 12:00-13:00

QLunch: The effect of noise in boson sampling

Speaker: Raúl Garcia-Patron, Université Libre de Bruxelles 

6 Nov. 2019, 12:00-13:00

QLunch:Varieties of sum of powers, Stiefel manifolds and their degrees

Speaker: Fulvio Gesmundo from QMATH

9 Oct. 2019, 12:00-13:00

QLunch: Dyonic zero-energy modes

Speaker: Michele Burrello from NBI

2 Oct. 2019, 12:00-13:00

QLunch: Quantum correlations under restricted transfer of information

Speaker: Jonatan Bohr Brask from DTU

21 Aug. 2019, 12:00-13:00

QLunch: A polynomial-time algorithm for ground states of spin trees

Speaker: Nilin Abrahamsen from MIT

3 July 2019, 12:00-13:00

QLunch: Exact correlation functions of the principal chiral model

Speaker: Peter Orland, Baruch College, CUNY.

29 May 2019, 12:00-13:00

QLunch: Hamiltonian Learning on Superconducting Qubits Using Bayesian Inference

Speaker: Natalie Pearson from ETH Zürich/NBI

24 Apr. 2019, 12:00-13:00

QLunch: A Quantum Kac Model

Speaker: Michael Loss, Georgia Institute of Technology

3 Apr. 2019, 12:00-13:00

QLunch: Faces of the Stabiliser Polytope and Robustness Measures

Speaker: Arne Heimendahl, Universität zu Köln

23 Jan. 2019, 12:00-13:00

QLunch: Summoning Quantum Information

Speaker: Ignacio Amores Sesar, University of Copenhagen

9 Jan. 2019, 12:00-13:00

QLunch: An index theorem for quantum charge transport

Speaker: Alex Bols from KU Leuven

21 Nov. 2018, 12:00-13:00

QLunch: The structure of 3-dimensional causal triangulations

Speaker: Thordur Jonsson, University of Iceland

24 Oct. 2018, 12:00-13:00

QLunch: Formulas of Szegő type for the periodic Schrödinger operator

Speaker: Bernhard Pfirsch from University College London 

5 Sept. 2018, 12:00-13:00

QLunch: Constructing local frustration free Lindbladians with given MPDOs as stable space

Speaker: Dmytro Bondarenko from University of Hannover

30 May 2018, 12:00-13:00

QLunch: Quasi-factorization of the quantum relative entropy

Speaker: Angela Capel from Universidad Autónoma de Madrid

17 May 2018, 15:15-16:00

GAMP/QMATH Seminar: Tsirelson's problems and the entanglement breaking rank

Speaker: Jitendra Prakash from University of Waterloo

4 Apr. 2018, 12:00-13:00

QLunch: Schur-Weyl duality and entanglement

Speaker: Robin Reuvers from University of Cambridge

21 Mar. 2018, 13:00-14:00

QLunch: Oddities of Quantum colorings

Speaker: Laura Mančinska from QMATH

28 Feb. 2018, 12:00-13:00

QLunch: Connes' embedding problem and quantum XOR games

Speaker: Samuel Harris, University of Waterloo

14 Feb. 2018, 12:00-13:00

QLunch: Quantum computing with Fibonacci anyons

Speaker: Claire Levaillant from University of California

7 Feb. 2018, 12:00-13:00

QLunch: Hardy-Lieb-Thirring Inequalities for Fractional Pauli Operators

Speaker: Gonzalo Bley from Aarhus University

31 Jan. 2018, 12:00-13:00

QLunch: A Note on Arbitrary Group Quantum-Secure PRPs

Speaker: Hector Bjoljahn Hougaard

11 Jan. 2018, 15:15-16:15

GAMP/QMATH Lecture: Semidefinite Optimization for Quantum Information Processing

Speaker: Xin Wang from University of Technology Sydney

6 Dec. 2017, 12:00-13:00

QLunch: Markovianizing cost of tripartite quantum states

Speaker: Eyuri Wakakuwa, University of Tokyo, Japan

22 Nov. 2017, 12:00-13:00

QLunch: Communication games reveal preparation contextuality

Speaker: Armin Tavakoli from University of Geneva

15 Nov. 2017, 12:00-13:00

QLunch: Unforgeable quantum encryption

Speaker: Christian Majenz from Qusoft

1 Nov. 2017, 12:00-13:00

QLunch: On the interplay between algebraic geometry and complexity theory

Speaker: Fulvio Gesmundo from QMATH

25 Oct. 2017, 12:00-13:00

QLunch: Geometry of the quantum set of correlations

Speaker: Jed Kaniewski from QMATH

27 Sept. 2017, 12:00-13:00

Quantum Lunch: The Lee-Huang-Yang Formula for Dilute Bose Gases

Speaker: Birger Brietzke from QMATH

6 Sept. 2017, 12:00-13:00

QLunch: The Entropy Power Inequality with quantum memory

Speaker: Giacomo De Palma from QMATH

22 Aug. 2017, 15:00-16:00

QMATH Lecture: Lieb-Thirring inequality and gradient correction

Speaker: Phan Thanh Nam from LMU München

16 Aug. 2017, 12:00-13:00

QLunch: The excitation spectrum of Bose gases interacting through singular potentials

Speaker: Chiara Boccato from Universität Zürich

22 June 2017, 14:00-15:00

QMATH Lecture: Logical paradoxes in deterministic quantum state injection

Speaker: Nadish de Silva, University College, London

21 June 2017, 12:00-13:00

Quantum Lunch: Peierls-Bogolyubov's inequality for deformed exponentials

Speaker: Frank Hansen from Tohoku University, Japan

20 June 2017, 14:00-15:00

QMATH/GAMP Lecture: Contextuality and Noncommuative Geometry in Quantum Mechanics

Speaker: Nadish de Silva, University College London 

14 June 2017, 12:00-13:00

Quantum Lunch: General Error Correction for MERA Codes

Speaker: Francesco Battistel

19 Apr. 2017, 12:00-13:00

QLunch: Quantum framework from simple physical principles for single systems

Speaker: Howard Barnum, University of Copenhagen and University of New Mexico 

18 Apr. 2017, 13:00-14:00

QMATH Lecture: Asymptotic entanglement concentration of W states

Speaker: Alonso Botero, University of South Carolina, Columbia

5 Apr. 2017, 12:00-13:00

QLunch: Astronomical telescopes with quantum memories

Speaker: Johannes Borregaard from QMATH

15 Mar. 2017, 12:00-13:00

Quantum Lunch: Local boundary states imply gap for the parent Hamiltonian of PEPS

Speaker: Michael Kastoryano from Quantop

1 Mar. 2017, 12:00-13:00

Quantum Lunch: Quantum simulations with noisy quantum computers

Kristan Temme from IBM

15 Feb. 2017, 12:00-13:00

Quantum Lunch: A Reformulation of the Dirac-Frenkel Principle and the Bogoliubov-de-Gennes equations

Speakers: Niels Benedikter and Jérémy Sok from QMATH

8 Feb. 2017, 12:00-13:00

QMATH/GAMP Lecture: Entropy accumulation

Speaker: Frédéric Dupuis from Masaryk University

3 Feb. 2017, 13:00-14:00

QMATH Lecture: On the dynamics of multi-component condensates: mixtures and spinors

Speaker: Alessandro Olgiati from SISSA Trieste

1 Feb. 2017, 12:00-13:00

Joint SYM and QMATH Lecture: Tsirelson's problem

Speaker: David Perez Garcia from Universidad Complutense de Madrid

25 Jan. 2017, 12:00-13:00

Quantum Lunch: The PPT^2 conjecture in dimension 3

Speaker: Alexander Müller-Hermes from QMATH

18 Jan. 2017, 12:00-13:00

Quantum Lunch: Feynman-Kac formulas for the ultra-violet renormalized Nelson model

Speaker: Oliver Matte

11 Jan. 2017, 12:00-13:00

Quantum Lunch: To what extent can information propagation decouple from energy propagation?

Speaker: Robert Jonsson, Chalmers Universitet Göteborg

4 Jan. 2017, 12:00-13:00

Quantum Lunch: Fun with diagram algebras

Speaker: Jørgen Rasmussen from University of Queensland

21 Dec. 2016, 12:00-13:00

Quantum Lunch: Quantum information on Jordan algebras

Speaker: Peter Harremoës

14 Dec. 2016, 12:00-13:00

Quantum Lunch: Self-testing of quantum states: how to identify which state Alice and Bob share by letting them play a (nonlocal) game

Speaker: Tim Coopmans from University of Amsterdam

23 Nov. 2016, 12:00-13:00

Quantum Lunch: Semi-device-independent quantum randomness generation

Speaker Jonatan Bohr Brask from University of Geneva

2 Nov. 2016, 12:00-13:00

Quantum Lunch: Nonabelian braiding by topological solitons

Speaker: Nuno M. Romão from University of Augsburg

19 Oct. 2016, 12:00-13:00

Quantum Lunch: Information-theoretic non-malleability and authentication

Speaker: Christian Majenz from QMATH

12 Oct. 2016, 12:00-13:00

Quantum Lunch: Picking holes and cutting corners to achieve Clifford gates with the surface code

Speaker: Benjamin James Brown from Quantop

21 Sept. 2016, 12:00-13:00

Quantum Lunch: Random tensor networks and multipartite entanglement

Speaker: Michael Walter

14 Sept. 2016, 12:00-13:00

Quantum Lunch: The martingale method meets the detectability lemma

Speaker: Angelo Lucia.

7 Sept. 2016, 12:00-13:00

Quantum Lunch: Schrödinger Operators in Some Curvature Problems

Speaker Niels Martin Møller

31 Aug. 2016, 12:00-13:00

Quantum Lunch: Disentangling entangled quantum states

Speaker: Sania Jevtic

24 Aug. 2016, 12:00-13:00

Quantum Lunch: Autonomous feedback for superconducting qubits

Speaker: Christian Kraglund Andersen from University of Aarhus

22 June 2016, 12:00-13:00

Quantum Lunch: Quantum entropy derived from first principles

Speaker: Frank Hansen, IEHE Tohoku University.

11 May 2016, 14:00-15:00

After Quantum Lunch: Entropy power inequalities for qudits

Speaker: Māris Ozols, University of Cambridge.

4 May 2016, 12:00-13:00

Quantum Lunch: Quantum gate learning in engineered qubit networks: Toffoli gate with always-on interactions

Speaker: Leonardo Banchi, UCL.

30 Mar. 2016, 12:00-13:00

Quantum Lunch: Key Distillation

Speaker: Roberto Ferrara.

23 Mar. 2016, 12:00-13:00

Quantum Lunch: Dirac operators with magnetic link

Speaker: Jeremy Sok.

2 Mar. 2016, 12:00-13:00

Quantum Lunch: Tradeoff bounds for local error correction

Speaker: Michael Kastoryano, NBIA.

24 Feb. 2016, 12:00-13:00

Quantum Lunch: Pattern formation in biological systems & Electroweak baryogenesis in 2HDMs

Speaker: Nils Hermansson Truedsson, Dep. of Astronomy and Theoretical Physics, Lund University.

10 Feb. 2016, 12:00-13:00

Quantum Lunch: Trace inequalities for arbitrary many matrices via pinching

Speaker: Mario Berta, Caltech.

13 Jan. 2016, 12:00-13:00

Quantum Lunch: A Pfaffian formula for monomer-dimer partition functions

Speaker: Ian Jauslin.

6 Jan. 2016, 12:00-13:00

Quantum Lunch: Determinism and causality. Which aspects are shared between classical physics and quantum physics?

Speaker: Peter Harremoes

16 Dec. 2015, 12:00-13:00

Quantum Lunch

Speaker: Chris Perry

Title: TBA

9 Dec. 2015, 12:00-13:00

Quantum Lunch: Variational Expressions for Quantum Relative Entropies

Speaker: Marco Tomamichel  (Joint work with Mario Berta and Omar Fawzi.)

Abstract: Distance measures between quantum states like the trace distance and the fidelity can naturally be defined by optimizing a classical distance measure over all measurement statistics that can be obtained from the respective quantum states. In contrast, Petz showed that...

2 Dec. 2015, 12:00-13:00

Quantum Lunch

Speaker: Magnus Goffeng

Title: K-theory and topological insulators

Abstract: This will be an introductory seminar aimed at showing some basic facts in index theory and K-theory in the context of topological insulators.

25 Nov. 2015, 12:00-13:00

Quantum Lunch

Speaker: n.n.

Title: TBA

18 Nov. 2015, 12:00-13:00

Quantum Lunch

Speaker: Courtney Brell

Title: Error-correction in non-abelian anyon models

Abstract:

Scalable anyonic topological quantum computation requires the error-correction of non-abelian anyon systems. In contrast to abelian topological codes ...

11 Nov. 2015, 12:00-13:00

Quantum Lunch

Speaker: Ulrich Linden, University of Stuttgart

Title: On the Fermi Polaron in Two Dimensions

Abstract: We investigate the quantum system of a Fermi gas interacting
attractively with a single impurity by contact interaction in a
two-dimensional box. The contact interaction is implemented by a
limiting procedure ...

4 Nov. 2015, 12:00-13:00

Quantum Lunch: Extensions of the entanglement entropy for symmetry protected topological order

Title: Extensions of the entanglement entropy for symmetry protected topological order

Speaker: Shunji Matsuura

28 Oct. 2015, 12:00-13:00

Quantum Lunch: Interaction Effects in Spin-Wave Theory

Title: Interaction Effects in Spin-Wave Theory

Speaker: Niels Benedikter

21 Oct. 2015, 12:00-13:00

Quantum Lunch: Random permutations and the mean-field Heisenberg model

Title: Random permutations and the mean-field Heisenberg model

Speaker: Jakob Björnberg

14 Oct. 2015, 12:00-13:00

Quantum Lunch: Renormalising entanglement distillation

Speaker: Earl Campbell

Title: Renormalising entanglement distillation

7 Oct. 2015, 12:00-13:00

Quantum Lunch: Entanglement Measures

Title: Entanglement Measures

Speaker: Roberto Ferrara

30 Sept. 2015, 12:00-13:00

Quantum Lunch: Accurate atomic radii from Thomas-Fermi Theory

Title: Accurate atomic radii from Thomas-Fermi Theory

Speaker: Jan Philip Solovej

23 Sept. 2015, 12:00-13:00

Quantum Lunch: Bogoliubov correction to the mean-field dynamics of interacting bosons

Title: Bogoliubov correction to the mean-field dynamics of interacting bosons

Speaker: Marcin Napiórkowski

16 Sept. 2015, 12:00-13:00

Quantum Lunch: Quantum Circuits for Isometries

Title: Quantum Circuits for Isometries

Speaker: Raban Iten

Abstract: Every quantum operation can be decomposed into a sequence of single-qubit and Controlled-Not (C-NOT) gates. In many experimental architectures, single-qubit gates are relatively ‘cheap’ to perform compared to C-NOTs (for instance, being less susceptible to noise), and hence it is desirable to minimize the number of C-NOT gates required to implement a circuit. I will consider the task of constructing an arbitrary isometry from m qubits to n qubits, while trying to minimize the number of C-NOT gates required.  I will show a lower bound and then give an explicit gate decomposition that gets within a factor of about two of this bound. Through Stinespring’s theorem this points to a C-NOT-efficient way to perform an arbitrary quantum operation.

9 Sept. 2015, 12:00-13:00

Quantum Lunch

Speaker: Douglas Lundholm

Title: Anyons in the average-field approximation

2 Sept. 2015, 12:00-13:00

Quantum Lunch: Non-binding of strongly coupled many-polarons in dimensions two and three

Title: Non-binding of strongly coupled many-polarons in dimensions two and three

Speaker: Anton Samojlow

19 Aug. 2015, 12:00-13:00

Quantum Lunch: Estimates for the lowest eigenvalue of magnetic Laplacians.

Title: Estimates for the lowest eigenvalue of magnetic Laplacians.

Speaker: Fabian Portmann

1 July 2015, 12:00-13:00

Quantum Lunch: Localization from superselection rules in translation invariant systems

Speaker: Isaac Kim

Abstract: We study a translation invariant spin model in a three-dimensional regular lattice, called the cubic code model, in the presence of arbitrary extensive perturbations. Below a critical perturbation strength, we show that most states with finite energy are localized; the overwhelming majority of such states have energy concentrated around a finite number of defects, and remain so for a time that is near-exponential in the distance between the defects. This phenomenon is due to an emergent superselection rule and does not require any disorder. This is joint a joint work with Jeongwan haah.(1505.01480)

24 June 2015, 12:00-13:00

Quantum Lunch: Bogoliubov theory at positive temperature

Speaker: Robin Reuvers

Abstract: I will discuss Bogoliubov theory in the translation invariant case of a Bose gas. The theory arises by restriction to translation invariant quasi-free states. I will introduce the positive temperature pressure functional and the corresponding ground state energy functional...

17 June 2015, 12:00-13:00

Quantum Lunch: Quantum-information processing with solid-state single-photon sources

Speaker: Peter Lohdal (NBI)

10 June 2015, 12:00-13:00

Quantum Lunch: The fractional Laplacian on bounded domains

Speaker: Gerd Grubb

3 June 2015, 12:00-13:00

Quantum Lunch: Learning and testing of mixed state spectra

Speaker: John Wright

20 May 2015, 12:00-13:00

Quantum Lunch: Defining work from operational principles

Speaker: Henrik Wilming

13 May 2015, 12:00-13:00

Quantum Lunch: An adaptive attack on Wiesner's quantum money

Speaker: Daniel Nagaj (Slovak Academy of Sciences)

Abstract:

6 May 2015, 12:00-13:00

Quantum Lunch: an introduction to Hypercontractivity and Log-Sobolev inequalities, and their applications in Mathematical Physics and Quantum Information

Speaker: Michael Kastoryano

29 Apr. 2015, 12:00-13:00

Quantum Lunch: Factorizable completely positive maps and Quantum Information Theory

Speaker: Magdalena Musat

Title: Factorizable completely positive maps and Quantum Information Theory

22 Apr. 2015, 12:00-13:00

Quantum Lunch: Energy Levels of Dipoles in Graphene

Title: Energy Levels of Dipoles in Graphene

Speaker: Simone Rademacher

15 Apr. 2015, 12:00-13:00

Quantum Lunch

Speaker: TBA

Title: TBA

8 Apr. 2015, 12:00-13:00

Quantum Lunch

Speaker: Min-Hsiu Hsieh

25 Mar. 2015, 12:00-13:00

Quantum Lunch: Two results in topology, motivated by quantum computation

Title: Two results in topology, motivated by quantum computation

Speaker: Gorjan Alagic

18 Mar. 2015, 12:00-13:00

Quantum Lunch

Speaker: Olga Bershtein

Title: TBA

11 Mar. 2015, 12:00-13:00

Quantum Lunch: Heralded quantum gate with integrated error detection

Speaker: Johannes Borregaard

4 Mar. 2015, 12:00-13:00

Quantum Lunch: Error distributions on large entangled states with non-Markovian dynamics

Speaker: Dara McCutcheon

25 Feb. 2015, 12:00-13:00

Quantum Lunch: A flea on Schrödinger's cat

Speaker: Robin Reuvers

18 Feb. 2015, 12:00-13:00

Quantum Lunch: Cryptography

Speaker: Gorjan Alagic

11 Feb. 2015, 12:00-13:00

Quantum Lunch: Ground state entanglement constrains low energy excitations

Speaker: Benjamin Brown

4 Feb. 2015, 12:00-13:00

Quantum Lunch

Title: Dynamical Mean-Field Theory of Fermionic Systems

Speaker: Niels Benedikter

28 Jan. 2015, 12:00-13:00

Quantum Lunch

Title: Capacities for quantum memories

Speaker: Alexander Mueller-Hermes

Abstract: Quantum memories can be regarded as quantum channels that transmit information through time without moving it through space. Aiming at a reliable storage of information we may thus not only encode at the beginning and decode at the end, but also intervene during the transmission - a possibility not captured by the ordinary capacities....

21 Jan. 2015, 12:00-13:00

Quantum Lunch

Title: A mean-field approximation of QED

Speaker: Jeremy Sok

14 Jan. 2015, 12:00-13:00

Quantum Lunch: Finding large gaps between tensor rank and border rank via algebras

Speaker: Jeroen Zuiddam

Abstract: In quantum information theory, it is well-known that the GHZ-state 000+111 cannot be (SLOCC-)transformed into the W-state 000+101+011, but the W-state can be approximated with states from the GHZ-orbit. The W-state is thus an example of a tensor of tensor rank 3 that can be approximated by tensors of tensor rank 2....