Selected Talks (Videos)
The videos below are embedded by YouTube and only load when you click the play button. Google’s privacy policy applies. In particular, Google collects personal data in the form of cookies and in other forms. You can avoid this by not clicking the play button.
QIQT 2023 (4th International Conference on Quantum Information and Quantum Technology, 9 May 2023): Testing quantum theory by generalizing noncontextuality
It is a fundamental prediction of quantum theory that states of physical systems are described by complex vectors or density operators on a Hilbert space. However, many experiments admit effective descriptions in terms of other state spaces, such as classical probability distributions or quantum systems with superselection rules. Which probabilistic theories could reasonably be found as effective descriptions of physical systems if nature is fundamentally quantum? To answer this, we employ a generalized version of noncontextuality: processes that are statistically indistinguishable in an effective theory should not require explanation by multiple distinguishable processes in a more fundamental theory. From this, we propose an experimental test of quantum theory by probing single physical systems without assuming access to a tomographically complete set of procedures, arguably avoiding a significant loophole of earlier approaches.
Algebra, Particles, and Quantum Theory seminar series, 23 May 2022:
Quantum theory and Jordan algebras from simple principles
Quantum theory is one of our most successful physical theories, but its standard textbook formulation is mysterious. For example, why are states described by complex vectors in a Hilbert space, and why do observables correspond to self-adjoint operators? In this talk, I describe how the Hilbert space formalism of quantum theory (and its Jordan-algebraic generalizations) can be reconstructed from simple physical or information-theoretic principles, without presupposing any of the usual mathematical machinery. This is conceptually similar to the derivation of the Lorentz transformations from the principles of relativity and the constancy of the speed of light. To this end, I introduce the framework of “generalized probabilistic theories” which generalizes both classical and quantum probability theory and which describes all possible consistent ways in which preparations and measurements can interact statistically in a laboratory. I give an explicit example of a set of principles that implies quantum theory, describe how the hunt for “higher-order interference” led to a scientific detective story, and show how these insights and techniques can shed surprising light on the relation between quantum theory and spacetime.
Online seminar at OIST (Okinawa Institute of Science and Technology), 6 Feb. 2023: Theory-independent randomness generation with spacetime symmetries
We characterize how the response of physical systems to spatial rotations constrains the probabilities of events that may be observed. From a foundational point of view, we show that the set of quantum correlations in our scenarios can be derived from rotational symmetry alone, without assuming quantum physics. This shows that important predictions of quantum theory can be derived from the structure of space, demonstrating that semi-device-independent scenarios can be utilized to shed light on the foundations of physics. From a practical perspective, these results allow us to introduce semi-device-independent protocols for the generation of secure random numbers based on the breaking of spatial symmetries. While experimental implementations will rely on quantum physics, the security analysis and the amount of extracted randomness is theory-independent and certified by the observed correlations only. That is, our protocols rely on a physically meaningful assumption: a bound on a theory-independent notion of spin. Slides
“Nonlocal talks” online seminar (University of Campinas, Brazil), 25 Feb. 2021:
Physical Idealism
According to our current conception of physics, any valid physical theory is supposed to describe the objective evolution of a unique external world. However, this condition is challenged by quantum theory, which suggests that physical systems should not always be understood as having objective properties which are simply revealed by measurement. Furthermore, as argued below, several other conceptual puzzles in the foundations of physics and related fields point to limitations of our current perspective and motivate the exploration of an alternative: to start with the first-person (the observer) rather than the third-person perspective (the world).
In this work, I propose a rigorous approach of this kind on the basis of algorithmic information theory. It is based on a single postulate: that universal induction determines the chances of what any observer sees next. The resulting theory dissolves puzzles like cosmology’s Boltzmann brain problem, makes concrete predictions for thought experiments like the computer simulation of agents, and suggests novel phenomena such as “probabilistic zombies” governed by observer-dependent probabilistic chances. Related paper in Quantum
Thermodynamics as a Resource Theory: Foundational and Philosophical Implications, Rotman Institute of Philosophy, 22 June 2018:
Operational interpretation of entropy and free energy without the thermodynamic limit
According to the resource-theoretic approach, thermodynamics at the nanoscale behaves quite differently from its familiar counterpart in the regime of the thermodynamic limit: for example, the standard formulation of the second law (non-increase of the Helmholtz free energy) is replaced by an infinite family of “second laws”. However, this result has been obtained under an auxiliary assumption that can be lifted in some circumstances. Namely, here I show that microscopic thermal machines can exploit a strategy that is unavailable in the thermodynamic limit: they can substantially increase their efficiency by correlating themselves with their working medium in clever ways. I show that this allows them to overcome the infinite family of “second laws”, and to extract (or invest) the Helmholtz free energy difference in arbitrary state transitions exactly and basically without any fluctuations.
This restores the standard formulation of the second law at the nanoscale, and gives the free energy an operational interpretation without averaging and for single instances of a quantum system. Paper in PRX
Essentia Foundation’s 2020 online work conference, 16 Nov. 2020:
From enigmas in physics to a structural version of idealism
See also the interview by the Essentia Foundation for some more information.
Related paper in Quantum.
Recent Talks
Boldface title = invited talk.
- 18 Oct. 2024, The Case for Quantum Probabilism Workshop, IQOQI Vienna: Thinking twice inside the box: is Wigner’s friend really about quantum theory? Slides
- 26 June 2024, Seminar talk at the University of Regensburg, Faculty of Mathematics (online): Exact characterization of entropy and free energy without thermodynamic limit or averaging. Video, slides.
- 16 June 2024, Philosophy of Thermodynamics Workshop, Rotman Institute of Philosophy, Canada: Exact characterization of entropy and free energy without thermodynamic limit or averaging. Slides
- 14 March 2024, Billroth-Gymnasium Wien: Rätsel der Quantenwelt: lokaler Realismus, Quantenverschlüsselung und unser Universum.
- 10 Nov. 2023, RQI Circuit Vienna: How spacetime constrains the structure of quantum theory. Video
- 11 Sept. 2023, Rethinking the Foundations of Physics, LMU Munich: Testing quantum theory by generalizing noncontextuality. Slides
- 3 Aug. 2023, The Quantum Reconstructions Program and Beyond, University of Graz: Quantum theory from simple principles, spacetime, and what it tells us about interpretations. Video
- 9 July 2023, Foundations 2023, Bristol: Testing quantum theory by generalizing noncontextuality. Slides
- 2 June 2023, Physics Meets Philosophy workshop, Vienna: Information-theoretic idealism. Slides
- 24 May 2023, Borg3-Gymnasium Wien: Quantenphysik und der Satz von Bell.
- 09 May 2023, 4th International Conference on Quantum Information and Quantum Technology (QIQT) 2023: Testing quantum theory by generalizing noncontextuality. Video
- April 2023, QISS (Quantum Information Structure of Spacetime) Spring School: It from qubit underground. Slides, notes
- 17 March 2023, QISS Virtual Seminar: How spacetime constrains the structure of quantum theory. Video, slides
- 6 Feb. 2023, Poster at QIP (Quantum Information Processing) ’23, Ghent: Testing quantum theory with generalized noncontextuality. Poster
- 6 Feb. 2023, Online seminar at OIST (Okinawa Institute of Science and Technology): Theory-independent randomness generation with spacetime symmetries. Video
- 1 Dec. 2022, Wigner’s Friends Theory Workshop, The Institute, San Francisco: Why we should study other observer puzzles together with Wigner’s friend.
- 17-18 Nov. 2022, Moderation of Essentia Foundation’s Online Conference 2022 “Quantum physics and the first-person perspective”.
- 9 Sept. 2022, DPG Meeting Regensburg, Hauptvortrag (“main lecture”): Testing quantum theory with generalized noncontextuality. Slides
- 23 May 2022, Algebra, Particles, and Quantum Theory seminar series: Quantum theory and Jordan algebras from simple principles. Video
Talks before 2022
- 2 Nov. 2021, Habilitation Colloquium, University of Vienna: Quantum theory from simple principles. Slides
- 15 Oct. 2021, Quantum Boundaries 2021 workshop, Nottingham, UK (online): Quantum theory from simple principles. Video
- 1 Sept. 2021, University of Ulm (online): Black boxes in space and time: semi-device-independent information processing via representation theory. Slides
- 11 June 2021, Atominstitut, TU Wien: Black boxes in space and time: semi-device-independent information processing via representation theory. Slides
- 1 June 2021, Banff International Research Station, Quantum Foundations, Gravity, and Causal Order (online): Quantum reference frame transformations as symmetries and the paradox of the third particle. Video
- 19 May 2021, USI Lugano (online): Computational irreducibility and notions of simulation for Turing machines. Slides
- 18 March 2021, APS March Meeting (online): Black boxes in spacetime: semi-device-independent information processing with spatiotemporal degrees of freedom.
- 25 Feb. 2021, “Nonlocal talks” seminar (online), University of Campinas, Brazil: Physical idealism. Video
- 15 Dec. 2020, Harvard Mini-Workshop on Probability and Undecidability (Harvard Foundations of Physics Series): From undecidability as undifferentiation to physics “without a world”. Video
- 8 Dec. 2020, Conference on Quantum Foundations, Technology and Applications (QFTA) 2020, Mohali, India (online): Black boxes in space and time: semi-device-independent information processing via representation theory.
- 26 Nov. 2020, Online NITheP Workshop on Quantum Thermodynamics: On the repeatable use of quantum resources in thermodynamics. Video
- 16 Nov. 2020, Essentia Foundation Work Conference, Eindhoven: From enigmas of physics to a structural version of idealism. Video
- 9 Nov. 2020, Vienna Center for Quantum Science and Technology (VCQ) Colloquium talk: Black boxes in space and time: from quantum reconstructions to protocols. Slides
- 5 Oct. 2020, The Computing Community Consortium (CCC) Reversible Classical Computing Workshop (online): Reversible computing and the resource-theoretic approach to thermodynamics. Slides
- 22 Sept. 2020, Vienna Center for Quantum Science and Technology (VCQ) PI Day: Quantum Information Theory in the Foundations of Physics.
- 21 July 2020, ArtScience Monthly, STATE Studio Berlin: How are physics and math usually advertised, and what is my own motivation instead? Slides
- 5 Feb. 2020, 713. WE Heraeus-Seminar “Quantum Thermodynamics for Young Scientists”, Bad Honnef: Thermodynamics as a resource theory: versions of the second law(s). Slides
- 3 Dec. 2019, Prize talk for Best Paper Award by ÖAW, Austrian Academy of Sciences Festive Hall: Der zweite Hauptsatz der Thermodynamik für einzelne Quantensysteme.
- 24 July 2019, Foundational Questions Institute (FQXi)’s 6th International Conference, Castelvecchio Pascoli, Italy: Mind before matter — why and how consider “idealist” worldviews? Video
- 3-10 July 2019, Les Houches School of Physics on “Quantum Information Machines”: Quantum Foundations and Probabilistic Theories. Lecture Notes
- 27 June 2019, Quantum ThermoDynamics Conference, Espoo, Finland: Thermodynamics as a resource theory: versions of the second law(s). Slides
- 21 June 2019, Solstice of Foundations summer school, ETH Zurich: From observers to physics via information theory.
- 17 June 2019, Scientific Advisory Board Meeting, IQOQI Vienna: From correlation machines to spacetime boxes: a tour of informational physics.
- 1 June 2019, MCMP (Munich Center for Mathematical Philosophy)-Western Ontario Workshop on Computation in Scientific Theory and Practice: An approach in which the “first person” is fundamental and the external world is emergent.
- 23 May 2019, IQOQI Vienna Theory Breakfast: The second law in nanoscale thermodynamics and no-broadcasting of reference frame information. Slides
- 29 March 2019, Physics-Philosophy Meeting, University of Vienna: Quantum theory as a principle theory: insights from information-theoretic reconstructions. Slides
- 13 March 2019, Subjectivist interpretations of quantum probabilities, École Normale Supérieure, Paris: QBism, beliefs, and the world: a reversal of perspective.
- 11 Dec. 2018, IQOQI Vienna Mini Workshop on the Foundations of Quantum Mechanics: Exact operational interpretation of entropy and free energy without the thermodynamic limit. Slides
- 10 Dec. 2018, Online Seminar “Mind-Matter Relation”: Law without law – from observer states to physics via algorithmic information theory. Video
- 19 Nov. 2018, IQOQI Vienna semester start lecture: Information in the foundations of (quantum) physics: an overview.
- 30 Sept. 2018, Workshop on Causation and Complexity in the Conscious Brain, Aegina, Greece: Could the first person perspective be a fundamental aspect of physics?
- 26 Sept. 2018, 2nd Workshop on Biological Mentality, Michigan State University, Ann Arbor, MI: From mental states to physics via algorithmic information theory.
- 20 Aug. 2018, Seminar talk at ETH Zürich, Renato Renner’s group: From observers to physics via algorithmic information theory. Slides
- 22 June 2018, Interdisciplinary workshop “Thermodynamics as a Resource Theory: Foundational and Philosophical Implications”, University of Western Ontario, Canada: Operational interpretation of entropy and free energy without the thermodynamic limit. Video
- 28 May 2018, Workshop “Interplay of Quantum Information, Foundations, and Gravity”, Vienna: Quantum theory and the structure of spacetime in the light of operationalism. Video
- 23 Mai 2018, Dirk Helbing’s “Salon am Schinkelplatz”, Berlin: Sind “Beobachter” fundamentaler als die Welt? Entwurf einer Theorie.
- 4 Mai 2018, Workshop “Scientific Theory Construction: Measurement and Empirical Constraints”, Université de Montréal: From observers to physics via algorithmic information theory.
- 12 April 2018, Algorithmic Information, Induction, and Observers in Physics, Perimeter Institute for Theoretical Physics: From observers to physics via algorithmic information theory. Video
- 3 April 2018, Observers in Quantum and Foil Theories, Perimeter Institute for Theoretical Physics: From observers to physics via algorithmic information theory. Video Part I, Video Part II
- 22 March 2018, IQOQI Vienna Theory Breakfast: Could the first-person perspective be fundamental and objective physics be emergent?
- 20 March 2018, Hauptvortrag at the DPG (German Physical Society) Meeting, Würzburg: Operational meaning of entropy and free energy without the thermodynamic limit. Slides
- 14 March 2018, Seminar at the University of California, Santa Cruz: Could the first-person perspective be fundamental and objective physics be emergent?
- 31 Jan. 2018, Seminar at the University of Cologne: Could the first-person perspective be fundamental and objective physics be emergent?
- 17 Jan. 2018, Selected contributed talk at QIP (Quantum Information Processing) 2018, Delft: Majorization, correlating catalysts, and the single-shot interpretation of entropic quantities. Slides
- 28 July 2017, Wolfson Quantum Foundations Bash, Oxford, UK: Quantum theory as a principle theory: insights from an information-theoretic reconstruction. Video
- 8 June 2017, Workshop on Participatory Realism, Stellenbosch, South Africa: Could the first-person perspective be fundamental and objective physics be emergent?
- 28 May 2017, New Directions in the Foundations of Physics, Tarquinia, Italy: Quantum Theory as a Principle Theory: Insights from an Information-Theoretic Reconstruction.
- 5 May 2017, Seminar talk jointly with Michael Cuffaro, University of Bristol, Department of Philosophy: A New Constructional System.
- 3 May 2017, Seminar talk jointly with Michael Cuffaro, Munich Center for Mathematical Philosophy: A New Constructional System.
- 7 April 2017, Applied Mathematics Colloquium, University of Western Ontario, Canada: A Hamiltonian for the zeros of the Riemann zeta function. Slides
- 7 Dec. 2016, Simons Institute Workshop on Compositionality, University of Berkeley, California: Composition and quantum theory: a conjecture, and how it could fail. Video
- 2 Dec. 2016, Seminar at École Normale Supérieure, Paris: From physical principles to quantum theory and beyond.
- 30 Sept. 2016, Condensed Matter Day at Perimeter Institute for Theoretical Physics: Eigenstate thermalization: towards a general theorem.
- 4 Aug. 2016, Formulating and Finding Higher-order Interference workshop, Perimeter Institute for Theoretical Physics: Does relativistic causality constrain interference phenomena? Video
- 28 July 2016, It From Qubit Summer School, Perimeter Institute for Theoretical Physics: Eigenstate thermalization hypothesis. Video
- 18 July 2016, Foundations 2016 at London School of Economics: An operational approach to spacetime symmetries: Lorentz transformations from quantum communication. Slides
- 14 July 2016, Birkhoff-von Neumann Prize Lecture, Biennial Meeting of the International Quantum Structures Association, Leicester, UK: Interference, spacetime, and the structure of quantum information. Slides
- 26 Nov. 2015, PI Day, Perimeter Institute for Theoretical Physics: The Page curve from less than the full quantum formalism. Slides
- 9 Nov. 2015, Workshop on Quantum Correlations, Contextuality and All That… Again, International Institute of Physics, Natal, Brazil: Consistency with thermodynamics and higher-order interference in reconstructions of quantum theory.
- 16 Oct. 2015, Second AGM Meeting on Geometric Quantum Dynamics, Brunel University London, UK: Spacetime and the state space geometry of quantum theory.
- 13 Oct. 2015, Selected contributed talk at the 3rd Conference on Quantum Thermodynamics, October 11-16 2015, Porquerolles Island, France: Stochastic independence as a resource in small-scale thermodynamics. Slides
- 7 Oct. 2015, Applied Mathematics Colloquium, University of Western Ontario, Canada: From physical principles to quantum theory and beyond.
- 24 Sept. 2015, Mathematics Colloquium, University of Western Ontario, Canada: Majorization, thermodynamics, and a characterization of Shannon entropy.
- 26 Aug. 2015, Workshop on Contextuality: Why and How?, Linköping University, Sweden: Consistent exclusivity and interference in probabilistic theories. Slides
- 14 Aug. 2015, Mini-Workshop on the Foundations of Thermodynamics and Statistical Mechanics, Rotman Institute of Philosophy, London, ON, Canada: A resource-theoretic approach to thermodynamics. Slides
- 13 May 2015, Information Theoretic Foundations for Physics conference, Perimeter Institute for Theoretical Physics, Canada: Quantum theory and spacetime: strange allies. Video
- 31 March 2015, Rethinking Foundations of Physics workshop, Dorfgastein: Physics from a first-person perspective: from induction to objective laws of nature.
- 8 Dec. 2014, Kolloquium der Theoretischen Physik, FAU Erlangen: From physical principles to quantum theory and beyond.
- 5 Nov. 2014, Colloquium of the Perimeter Institute for Theoretical Physics, Canada: Quantum theory and spacetime: a different perspective. Video
- 13 June 2014, Quantum Theory: from Problems to Advances conference, Växjö, Sweden: Quantum theory and spacetime: progress from principles. Slides
- 5 June 2014, Seminar at Heidelberg University, Germany: Thermalization and canonical typicality in translation-invariant quantum lattice systems. Slides
- 3 April 2014, Sydney Meeting on Quantum Foundations, Sydney, Australia: Interference and spacetime: what GPTs can teach us about physics. Slides
- 20 Jan. 2014, COST conference on Thermodynamics in the Quantum Regime, Postdam, Germany: Thermalization and canonical typicality in translation-invariant quantum lattice systems. Slides
- 9 Jan. 2014, 4th International Conference on the Physics of Information, FQXi, Vieques, Puerto Rico: Space-time and the quantum: uncovering hidden links with information theory. Video
- 2 Aug. 2013, Seminar at Max Planck Institute of Quantum Optics, Garching, Germany: Thermalization from entanglement in translation-invariant quantum systems.
- 31 July 2013, The 17th UK and European Meeting on the Foundations of Physics, Munich: Axiomatic reconstructions and generalizations of quantum theory. Slides
- 26 July 2013, LOOPS ’13 Conference at Perimeter Institute for Theoretical Physics, Canada: From information-theoretic axioms to quantum theory and beyond. Video (starting at 20:50 Min.)
- 24 May 2013, Condensed Matter Seminar, Perimeter Institute for Theoretical Physics, Canada: Gibbs state from entanglement in translation-invariant quantum systems.
- 21 March 2013, APS March Meeting, Baltimore, MD, USA: Three-dimensionality of space and the quantum bit: an information-theoretic approach. Slides Invited talk and Press Conference.
- 15 Jan. 2013, Seminar talk at the Department of Physics and Astronomy, Heidelberg University, Germany: Statistical physics and beyond: fundamental insights from quantum information theory.
- 23 Oct. 2012, Seminar talk at ETH Zurich: Undecidability in quantum measurements. Slides
- 23 Oct. 2012, Q+ Hangout Talk (online): Three-dimensionality of space and the quantum bit: an information-theoretic approach. Video
- 9 Oct. 2012, Seminar talk at the Max Planck Institute for Quantum Optics, Munich: A derivation of quantum theory from physical requirements. Slides
- 3 Oct. 2012, Seminar talk at the Institute for Quantum Optics and Quantum Information, Vienna: Three-dimensionality of space and the quantum bit: an information-theoretic approach. Slides
- 22. – 24. Sept. 2012, Poster at the Quantum Information meets Statistical Mechanics conference, University of Innsbruck, Austria: Canonical typicality for translation-invariant quantum many-body systems. Poster
- 5 July 2012, Seminar talk at the quantum gravity group meeting, Perimeter Institute for Theoretical Physics, Canada: Physics, information and inverse Solomonoff induction.
- 1 May 2012, Seminar talk at the Perimeter Institute for Theoretical Physics, Canada: An information-theoretic approach to space dimensionality and quantum theory. Slides, Video
- 5 April 2012, Quantum Foundations workshop, Barbados: Information-theoretic approach to space dimensionality and quantum theory.
- 15 March 2012, Seminar talk at the Institute for Quantum Computing (IQC), University of Waterloo: Concentration of measure and the mean energy ensemble. Slides
- 30 Jan. 2012, Seminar talk at the quantum foundations group meeting, Perimeter Institute for Theoretical Physics, Canada: Canonical typicality for translation-invariant quantum spin systems.
- 12 Dec. 2011, Poster at QIP (Quantum Information Processing) 2012, Université du Quebec à Montreal, Canada: Undecidability of Quantum Measurement Occurrence. Poster
- 7 Dec. 2011, Workshop on Quantum Foundations in the Light of Quantum Information Theory III, Montréal, Canada: Reversibility as an axiom for quantum theory and the search for its closest cousins. Slides
- 2 Dec. 2011, Seminar talk at the University of Toronto: Undecidability in quantum measurements. Slides
- 18 Oct. 2011, Quantum foundations seminar at the Perimeter Institute for Theoretical Physics, Canada: The power of reversible computation determines quantum mechanics’ self-duality.
- 26 Sept. 2011, Quantum information seminar at the Perimeter Institute for Theoretical Physics, Canada: Undecidability in the theory of quantum channels.
- 20 Sept. 2011, Discussion group on quantum information and string theory, Perimeter Institute for Theoretical Physics, Canada: Quantum Quenches, Thermalization & Concentration of Measure.
- 23 Aug. 2011, Seminar talk at the Max Planck Institute for Mathematics in the Sciences, Leipzig: From operational axioms to quantum theory – and beyond?
- 9 Aug. 2011, Quantum Information and Foundations of Thermodynamics Workshop, ETH Zurich, Switzerland: Typical entanglement, coin tossing, and a general-probabilistic decoupling theorem. Slides
- 9 May 2011, Conceptual Foundations and Foils for Quantum Information Processing, Perimeter Institute for Theoretical Physics, Canada: From operational axioms to quantum theory – and beyond? Video
- 22 March 2011, APS March Meeting, Dallas, Texas, USA: A derivation of quantum theory from physical requirements.
- 15 March 2011, Quantum foundations seminar talk at the Perimeter Institute for Theoretical Physics, Canada: From operational axioms to quantum theory – and beyond?
- 3 Feb. 2011, Seminar talk at the Department of Mathematics, University of Erlangen-Nuremberg, Germany: A derivation of quantum theory from operational axioms.
- 2 Feb. 2011, Special Colloquium talk at the Institute of Physics, University of Freiburg, Germany: Entanglement, Concentration of Measure, and the Foundations of Statistical Mechanics.
- 11 Jan 2011, Poster at QIP (Quantum Information Processing) 2011, Singapore: Concentration of measure for quantum states with a fixed expectation value. Poster
- 14 Dept. 2010, International Symposium on Quantum Thermodynamics: Energy and Information Flow at the Nano-Scale, University of Stuttgart, Germany: Concentration of measure and the mean energy ensemble. Slides
- 22 July 2010, Seminar talk at the Institute of Physics and Astronomy, University of Potsdam, jointly with Carlos Pineda: Random matrix theory and concentration of measure.
- 8 June 2010, Fundamentals of Physics and Information workshop, ETH Zurich, Switzerland: Properties of Measurements in Generalized Probabilistic Theories and Axioms for Quantum Theory.
- 11-14 May 2010, Poster at the Workshop of the A2 Quantum Information Consortium, Schloss Reisensburg, Günzburg, Germany: Concentration of measure and the mean energy ensemble. Poster
- 8 March 2010, DPG (German Physical Society) Spring Meeting 2010, Hannover, Germany: All reversible dynamics in maximally non-local theories are trivial. Slides
- 22 Jan. 2010, Selected contributed talk at the Quantum Information Processing (QIP) 2010 conference, Zurich, Switzerland: All reversible dynamics in maximally non-local theories are trivial. Slides, Video
- 21 Jan. 2010, Poster at the Quantum Information Processing (QIP) 2010 conference, Zurich, Switzerland: Concentration of measure and the mean energy ensemble. Poster
- 7 Dec. 2009, Seminar talk at the Perimeter Institute for Theoretical Physics, Canada: Concentration of measure and the mean energy ensemble. Video
- 2 Oct. 2009, Workshop of the A2 Quantum Information Consortium, Hannover, Germany: Concentration of measure for quantum states with fixed mean energy.
- 17 April 2009, Seminar talk at the Max Planck Institute for Mathematics in the Sciences, Leipzig: Concentration of measure, typical quantum states with fixed mean energy, and emergence of Gibbs states. Slides
- 27 March 2009, QQQ (Quantum Information, Quantum Optics, and Quantum Many-Body Theory) meeting, Berlin, Germany: Concentration of measure, typical quantum states with fixed mean energy, and emergence of Gibbs states.
- 7 Oct. 2008, Seminar talk at the Max Planck Institute for Mathematics in the Sciences, Leipzig: Effective Complexity. Slides
- 14 – 19 Sept. 2008, DMV (German Mathematical Society) Annual Conference, Erlangen, Germany: Convex Trace Functions on Quantum Channels and the Additivity Conjecture. Slides
- 16 July 2008, The 2008 World Congress in Computer Science, Computer Engineering, and Applied Computing (WORLDCOMP’08), Las Vegas, Nevada, USA: Quantum Bit Strings and Prefix-Free Subspaces. Slides
- 12 June 2008, Seminar talk at QCI Bristol, UK: Convex trace functions on quantum channels and the additivity conjecture.
- 1-5 Oct. 2007, Selected contributed talk at the 4th European Conference on Complex Systems (ECCS 2007), Dresden: On the Quantum Complexity of Classical Words. Slides
- 6 Jan. 2007, Joint Mathematics Meetings of the AMS and MAA, New Orleans, LA, USA AMS Session on Applications of Mathematics, II: Strongly Universal Quantum Turing Machines & Invariance of Kolmogorov Complexity. Slides
- Aug. 2006, Seminar talk at the Centre for Quantum Computation, Cambridge: Entropy and Quantum Kolmogorov Complexity: a Quantum Brudno’s Theorem.
- 15 March 2006, DPG (German Physical Society) Spring Meeting 2006, Frankfurt am Main, Germany: Entropy and Quantum Kolmogorov Complexity: a Quantum Brudno’s Theorem.
- 29 Aug. 2005, ERATO conference on Quantum Information Science 2005, Tokyo, Japan: Entropy and Algorithmic Complexity in Quantum Information Theory – a Quantum Brudno’s Theorem. Slides
- 18 Aug. 2003, Orthogonal Polynomials, Special Functions and Applications conference, Copenhagen, Denmark: Fractional Sums and Euler-like Identities. Slides
- 18 Oct. 2002, Invited seminar at the University of Tübingen.
- 29 July – 2 Aug. 1996, Junior Mathematical Congress 1996, Miskolc, Hungary.