-
Dr Joshua Foo (Kyushu University)25/05/2026, 09:20Invited Talk
Optical clocks based on atoms and ions probe relativistic effects with unprecedented sensitivity. They resolve time dilation due to atom motion or different positions in the gravitational potential through frequency shifts. However, all measurements of time dilation so far can be explained effectively as the result of dynamics with respect to a classical proper time parameter. Here we show...
Go to contribution page -
Mr Achintya Sajeendran (University of Queensland)25/05/2026, 10:00
The time-energy uncertainty relation is often invoked as a heuristic explanation for virtual particles in interacting quantum field theory. However, this interpretation breaks down upon closer scrutiny for several reasons. Although concrete derivations and interpretations of time-energy uncertainty bounds in quantum mechanics have been established, most famously by Mandelstam and Tamm in 1945,...
Go to contribution page -
Mr Akhil Deswal (Indian Institute of Science Education & Research (IISER))25/05/2026, 11:00
Time in quantum theory is operational, it is inferred from physical processes used as clocks and from temporal correlations registered by quantum systems. The Unruh effect is a striking manifestation of this idea, uniform acceleration changes the detector's notion of time and yields a thermal response in vacuum, linking time and motion. We developed time-resolved approach to detect Unruh...
Go to contribution page -
Ms Amrapali Sen (International Centre for Theory of Quantum Technologies)25/05/2026, 11:20
Quantum theory is widely regarded as fundamentally indeterministic, yet classical frameworks can also exhibit indeterminism once infinite information is abandoned. At the same time, relativity is usually taken to forbid superluminal signalling, yet Lorentz symmetry formally admits superluminal transformations (SpTs). Dragan and Ekert have argued that SpTs entail indeterminism analogous to the...
Go to contribution page -
Prof. Alex Matzkin (LPTM (CNRS and CY Cergy Paris Univ.))25/05/2026, 11:40
Many recent experimental works involving quantum tunneling claim their observations are consistent with superluminal or instantaneous barrier traversal times. However, we have recently proved [1] that microcausality prevents superluminal dynamics in the presence of tunneling in a QFT framework in which a potential barrier is represented by a background field. In this talk I will discuss how...
Go to contribution page -
Prof. Jan Klaers (University of Twente)25/05/2026, 14:00Invited Talk
Although quantum tunnelling has been studied since the inception of quantum mechanics, some aspects remain controversial, particularly the duration of tunnelling events. In a recent experiment [1], we investigate the quantum-mechanical motion of particles in a system of two coupled waveguide potentials, where population transfer between the waveguides acts as a clock, enabling the measurement...
Go to contribution page -
Mr Apostolos Giovanakis (ETH Zurich)25/05/2026, 15:20Poster
A central question in the study of quantum information theory in the presence of symmetries concerns which properties of a system can be inferred by observers without access to the laboratory frame. We show how using a quantum system as a reference frame allows one to evade symmetry constraints, focusing on systems that can serve as quantum clocks. However, realistic quantum clocks cannot...
Go to contribution page -
Ms Bruna Sahdo (IQOQI-Vienna)25/05/2026, 15:20Poster
The tensor product rule for composing subsystems is central to information-theoretic formulations of Quantum Theory. Adopting a relational view, we describe the adding and removing of subsystems in a quantum reference frame (QRF) for finite discrete translations following E. Castro-Ruiz, O. Oreshkov (2025). We show that textbook compositional rules only hold in a QRF perspective if the...
Go to contribution page -
Mr Elia Sciama Bandel (University of Bristol)25/05/2026, 15:20Poster
Quantum clocks, such as atomic clocks, are known to have advantages over classical ones. Autonomous quantum clocks are a relatively new addition to this realm. What makes them particularly interesting is the little external control they need. My research is focused on a minimal thermal clock model previously proposed. This consists of two qubits operating between macroscopic heat baths,...
Go to contribution page -
Ms María Rosa Preciado-Rivas (University of Waterloo)25/05/2026, 15:20Poster
Contextuality, a key resource for quantum advantage, describes systems in which the outcome of a measurement is not independent of other compatible measurements, in contrast to classical hidden-variable descriptions. We investigate the harvesting of contextuality from the vacuum of a quantum field using Unruh-DeWitt detectors. We show that localized interactions with the field can endow...
Go to contribution page -
Ms Nina Mazurewicz (University of Warsaw)25/05/2026, 15:20Poster
The nature of time and its genuine passage are central problems at the interface of physics and philosophy. Inspired by Nicolas Gisin’s argument that free will is essential for rational reasoning and therefore implies the reality of temporal passage, this study examines how the structure of time may be understood in universes admitting Closed Timelike Curves (CTCs), and what implications such...
Go to contribution page -
Dr Tom Rivlin (TU Wien)25/05/2026, 15:20Poster
The Wigner’s Friend thought experiment, where two observers disagree about experimental outcomes due to different models of measurements, has long been used to frame questions in quantum foundations. It has also recently seen a resurgence as a way to produce novel nonclassical effects such as the Local Friendliness Inequalities (LFIs). But few works have approached these topics using the...
Go to contribution page -
Mrs Marina Pisaturo (Universität Bremen)25/05/2026, 15:20Poster
The interplay between quantum theory and gravity is still an open problem. Here, we investigate the dynamics of gravitationally induced entanglement in a single photonic state delocalized in a three-arms interferometer, each hosting quantum memories, in Earth's gravitational field. The output statistics can be related to entanglement measures, enabling the study of the dynamics of correlations...
Go to contribution page -
Prof. Lorenzo Maccone (Università di Pavia, INFN Pavia)25/05/2026, 15:20Poster
We detail how the Dirac equation can be expressed in the fully covariant relativistic quantum mechanics framework of the Geometric Event based quantum mechanics (GEB).
Go to contribution page -
Mr Eleftherios Stamatelopoulos (University of Patras)25/05/2026, 15:20Poster
Understanding how quantum systems interact gravitationally remains an important open problem at the interface of quantum theory and general relativity. While a complete theory of quantum gravity is still lacking, valuable insight can be gained by studying quantum matter coupled to gravity in the weak field regime. In this work we investigate the gravitational interaction of quantum systems...
Go to contribution page -
Ms Magdalini Zonnios (Trinity College Dublin)25/05/2026, 15:20Poster
How much memory does a quantum device need to tell two multi-time processes apart? We study process discrimination in a realistic regime where the probing device is reusable, time-homogeneous, and limited to finite coherent memory. While the strategy norm captures the ultimate power of arbitrary adaptive testers, it generally presumes step-dependent control and unbounded quantum memory. We...
Go to contribution page -
Mr Nicolás Medina Sánchez (University of Vienna)25/05/2026, 15:20Poster
In generally covariant theories, physical configurations are defined modulo diffeomorphisms, and the induced equivalence relation is highly singular. In particular, recent results show that complete sets of observables need not be Borel-definable, and their existence may fail within standard measurable frameworks. This obstructs any direct parametrisation of spacetime geometry in terms of...
Go to contribution page -
Dr Michael Suleymanov (Bar-Ilan University)25/05/2026, 15:20Poster
Existing approaches to relativistic quantum reference frames typically begin by assuming Lorentz or Poincaré symmetry and then constructing quantum frame transformations compatible with that structure. Here we propose an alternative route based on a minimal physical postulate: the existence of a perspective-invariant maximal velocity. Working within a timeless, constraint-based formulation in...
Go to contribution page -
Ms Rashi Kaimal (University of Tübingen)25/05/2026, 15:20Poster
We are concerned with the justification of the statement, commonly (explicitly or implicitly) used in quantum scattering theory, that for a free non-relativistic quantum particle with initial wave function $\Psi_0(\mathbf{x})$, surrounded by detectors along a sphere of large radius $R$, the probability distribution of the detection time and place has asymptotic density (i.e., scattering cross...
Go to contribution page -
Mr Patryk Michalski (University of Warsaw)25/05/2026, 15:20Poster
The two-state vector formalism is a time-symmetrised approach to quantum theory. Although its predictions can be derived from the principles of standard quantum mechanics, recent developments in constructing a covariant quantum field theory of particles with negative squared mass suggest that it may constitute a preferred interpretation. In our work, we identify an overlooked aspect of the...
Go to contribution page -
Mr Paolo Luppi (University of Milan)25/05/2026, 15:20Poster
Understanding what makes a quantum process genuinely nonclassical in time is a central question in the foundations of quantum theory. We investigate this question in continuous-time quantum walks by comparing two operational notions of quantumness: a single-time measure based on the quantum–classical dynamical distance, and a multi-time quantifier based on violations of Kolmogorov consistency...
Go to contribution page -
Dr Rick Perche (Stockholm University)25/05/2026, 15:20Poster
Vacuum fluctuations in quantum field theory impose fundamental limitations on our ability to measure time in short scales. To investigate the impact of universal quantum field theory effects on observer-dependent time measurements, we introduce a clock model based on the vacuum decay probability of a finite-sized quantum system. Using this model, we study a microscopic twin paradox scenario...
Go to contribution page -
Dr Vilasini Venkatesh (University of Grenoble Alpes)26/05/2026, 09:00Invited Talk
-
Dr Shashaank Khanna (LIS, CNRS, Aix-Marseille University)26/05/2026, 09:40Talk
Bell’s eponymous theorem implies that Quantum Mechanics is incompatible with local causality. This leads to tension between Relativity and Quantum Theory because certain quantum correla- tions cannot be explained locally. Non-classicality of such quantum correlations is often realized to arise because of their non-local nature. Making use of the framework of classical causality and causal...
Go to contribution page -
Dr Matt Wilson (CentraleSupelec, University of Paris-Saclay)26/05/2026, 10:00Talk
The framework of higher-order quantum operations (process matrices/supermaps) on finite-dimensional systems is primarily motivated by providing an information-theoretic abstraction of a spacetime environment. In doing so, it provides a way to extract operational causal structure from quantum circuit configurations, and a way to formalise quantum (indefinite) causal structures, which have been...
Go to contribution page -
Mr Stanislav Filatov (University of Latvia)26/05/2026, 11:00Talk
This talk investigates an interpretation of the quantum switch by projecting its spatial paths into a superpositional basis. By redefining traditional operations as delocalized superpositional processes, we explore whether indefinite causal order can be recast as a definite sequential evolution through superposed identities. We specifically consider configurations where a particle might...
Go to contribution page -
Ms Hannah Seabrook (University of Bristol)26/05/2026, 11:20Talk
Device-independent (DI) tests draw conclusions about nature solely from observed correlations, without trusting the devices used. Originating in Bell's work on nonlocality, this paradigm has become central to foundational studies of quantum theory and practical applications (e.g., cryptography). More recently, DI tests of indefinite causal order (ICO) have extended this approach to more exotic...
Go to contribution page -
Mr Matthias Salzger (International Centre for Theory of Quantum Technologies, University of Gdańsk)26/05/2026, 11:40Talk
In quantum causality and quantum information, there is a vast landscape of abstract quantum protocols that permit cyclic or non-acyclic causal structures between quantum operations. This includes widely studied frameworks for indefinite causal order and higher-order quantum processes, such as process matrices. However, a longstanding open question has been which is the largest class of such...
Go to contribution page -
Prof. Eddy Chen (University of California San Diego)26/05/2026, 14:00Invited Talk
According to density matrix realism, the quantum state of the universe is objective but could be fundamentally mixed. I develop this framework and motivate it using considerations about the arrows of time. I then present a new class of results—observation typicality—which establish fundamental limits on our ability to infer or distinguish universal quantum states from observations. I explore...
Go to contribution page -
Mr Joppe Widstam (Max Planck Institute for the Physics of Complex Systems)26/05/2026, 15:20Talk
Using Bayes' theorem and the quantum formalism, one can infer unobserved variables from observed variables in a quantum experiment [1]. Quantum mechanics specifies the physical relations among these variables. These relations can be expressed as a joint probability distribution which can then be factorized into a causal model. Based on [2-3] we propose a simple causal model in which the...
Go to contribution page -
Dr Kyrylo Simonov (University of Vienna)26/05/2026, 15:40Talk
Bidirectional devices are devices for which the roles of the input and output ports can be exchanged. Mathematically, these devices are described by bistochastic quantum channels, namely completely positive linear maps that are both trace-preserving and identity-preserving. Recently, it has been shown that bidirectional quantum devices can, in principle, be used in ways that are incompatible...
Go to contribution page -
Prof. Leon Loveridge (University of South-Eastern Norway)27/05/2026, 09:00Invited Talk
The famous Pauli theorem rules out the possibility of time observables being represented by self-adjoint operators in physically realistic theories. Nevertheless, often time-translation covariant POVMs do exist. When used as quantum reference frames, such `non-ideality' is sometimes viewed as an inconvenience. In this talk, I will argue that in some settings it is an important feature - for...
Go to contribution page -
Mr Samuel Fedida (University of Cambridge)27/05/2026, 09:40
We develop foundations for a relational approach to quantum field theory based on the operational quantum reference frames framework considered in a relativistic setting. Unlike other efforts in combining QFT with QRFs, we use the latter to provide novel mathematical and conceptual foundations for the former. We focus on scalar fields in Minkowski spacetime and discuss the emergence of...
Go to contribution page -
Mr Davide Mattei (University of Rome, Tor Vergata)27/05/2026, 10:00
We study the limitations for defining spatial and temporal intervals when the only available reference frame is a single composite quantum system, whose internal degrees of freedom serve as a temporal reference — a clock — and whose centre-of-mass degrees of freedom act as a spatial reference — a rod. By combining quantum speed limits with the mass–energy equivalence of special relativity, we...
Go to contribution page -
Dr Veronika Baumann (IQOQI Vienna)27/05/2026, 11:00
In relational quantum dynamics, evolution emerges via the correlations between some system of interest and a clock system, which plays the role of a temporal reference frame. Their combined state satisfies a Wheeler-de Witt-like constraint equation, and therefore does not evolve, leading to a „block universe“ picture. I will talk about temporal localization and causal relations, when comparing...
Go to contribution page -
Dr Ismael Lucas de Paiva (Universidade Federal de Pernambuco)27/05/2026, 11:20
In quantum theory, conservation laws are typically formulated at a statistical level, holding only on average across measurement outcomes. Recent work has shown that this limitation can be overcome in certain scenarios: by explicitly including the quantum reference frame associated with a system’s preparation, exact conservation can be recovered at the level of individual measurement outcomes....
Go to contribution page -
Ms Niyusha Hosseini (TU Wien)27/05/2026, 11:40Talk
The time-of-arrival problem asks for a probability distribution for when a quantum particle reaches a specified location. It has been the subject of decades of debate, exemplifying the lack of a self-adjoint time observable in quantum theory. In the Page–Wootters framework, time is a relational quantity, emerging from correlations between a system and a clock induced by a global Hamiltonian...
Go to contribution page -
Mr Florian Meier (Technische Universität Wien)27/05/2026, 14:00Talk
Creating precise timing devices at ultra-short time scales is not just an important technological challenge, but confronts us with foundational questions about timekeeping's ultimate precision limits. Research on clocks has either focused on long-term stability using an oscillator stabilized by a level transition, limiting precision at short timescales, or on making individual stochastic ticks...
Go to contribution page -
Dr Miguel Navascués (IQOQI Vienna)27/05/2026, 14:20Talk
Picture an experimental scenario where a closed quantum system, evolving through a time-independent Hamiltonian, is subject to a demolition measurement at a chosen time. The Hamiltonian, the measured observables, the initial state of the physical system and even its Hilbert space dimension are unknown; we nonetheless assume a promise or constraint on the energy distribution of the state. In...
Go to contribution page -
Mr Carlo Cepollaro (University of Vienna / IQOQI Vienna)27/05/2026, 14:40Talk
In this paper we address and propose a solution to the problem of the definition of work in quantum mechanics. We define a work operator for driven quantum systems by recasting the problem in an automatized picture, where the driving of the system is replaced by a time-independent interaction with a battery. In this energy-conserving setting, the work operator is recovered as the energy that...
Go to contribution page -
Dr Lucy James (University of Bonn)28/05/2026, 09:00Invited Talk
This talk raises several issues with standard explanations of time asymmetry, which assume a universally applicable statistical mechanical version of the second law of thermodynamics with a past hypothesis. The theme of criticism concerns the conceptual shifts which take place as thermodynamic entropy is reduced and the resulting definition (I focus on Boltzmann's) migrates between contexts....
Go to contribution page -
Mrs Julia Osęka-Lenart (Astronomical Observatory, Jagiellonian University)28/05/2026, 10:20Talk
The Schrödinger–Newton equation aims at describing the dynamics of massive quantum systems subject to the gravitational self-interaction. As a deterministic nonlinear quantum wave equation, it is generally believed to conflict with the relativistic no-signalling principle. Here I challenge this viewpoint and show that it is of a key importance to study the quantitative and operational...
Go to contribution page -
Prof. Martin Bojowald (The Pennsylvania State University)28/05/2026, 10:40Talk
A quantum object is extended by virtue of uncertainty. When subjected to gravity, different parts of its wave function experience distinct local relativistic effects, leading to tidal and interference phenomena absent in the classical limit. These effects can be incorporated into a geometric extension of classical spacetime. For states that are quantum correlated in at least two directions, a...
Go to contribution page
Choose timezone
Your profile timezone: