Canadian Quantum Research Center

Abstract The Unruh effect, a cornerstone of quantum field theory, predicts that an accelerating observer perceives a thermal bath of particles in a vacuum, bridging quantum mechanics and relativity. This study presents the first successful simulation of the Unruh effect on real quantum hardware, conducted at the Centre of Excellence for Technology, Quantum, and AI Canada (CETQAC). Using a two-qubit quantum circuit executed on IBM’s su perconducting qubits via Qiskit Runtime Services, we encoded the effect’s key features: quantum superposition, Bogoliubov transformations, and thermodynamic signatures. Re sults demonstrate a strong concentration in the |11⟩ basis state, with metrics such as pu rity (0.5), entropy (1.0), entanglement entropy (1.0), fidelity (0.46), and expectation value (Z =0.0) aligning with theoretical predictions. Visualizations, including statevector plots and Q-sphere representations, confirm the simulation’s success. This work advances quan tum thermodynamics and relativistic quantum physics, establishing Canada as a leader in quantum computing applications.

Since the discovery of controlled rotation in soap films under electric fields in 2009, the rotation of suspended liquid films has drawn attention across disciplines. While prior studies identified surface charge as a primary driver—particularly in polar liquids and liquid crystals—our work introduces a new influencing factor: the permittivity of the supporting frame. We show that the frame-to-film permittivity ratio governs the transition between slip and no-slip rotational modes. Using both Particle-Image Velocimetry (PIV) and visual inspection, we characterize these modes. Although PIV offers precise measurements, we demonstrate that the two rotational states can be visually distinguished through their color patterns. Films in no-slip rotation exhibit vivid, colored spiral fringe patterns, while slip modes display steady central patterns. These spiral fringes result from white light interference between the incident wave and the portion transmitted through the film and reflected back from the second surface. When the film’s thickness is below the temporal coherence length of white light, and its geometry resembles a hybrid lens–spiral-phase element, concentric fringes transform into dynamic, colored spirals. We propose that in the no-slip mode, the rotating film behaves as a lens-like spiral-phase object. The observed spiral pattern thus serves as both a qualitative signature and a physical indicator of the no-slip regime. This finding provides an accessible optical method for identifying rotational modes and offers new insights into the interplay between electromechanical forces, geometry, and optical behavior in thin liquid films.

In this paper, we base our analysis on the assumption that the existence of a photon sphere is an intrinsic characteristic of any ultra-compact gravitational structure with spherical symmetry. Utilizing the concept of a topological photon sphere, we categorize the behaviors of various gravitational models based on the structure of their photon spheres. This innovative approach enables us to define boundaries for black hole parameters, subsequently enabling us to classify the model as either a black hole or naked singularity. We demonstrate that the presence of this interplay between the gravitational structure and the existence of a photon sphere is a unique advantage that can be utilized from both perspectives. Our observations indicate that a gravitational model typically exhibits the behavior of a horizonless structure (or naked singularity) when a minimum effective potential (a stable photon sphere) appears within the studied spacetime region. Additionally, in this study, we investigate the effect of this structure on the behavior of the photon sphere by selecting models that are affected by Perfect Fluid Dark Matter (PFDM). Finally, by analyzing a model with multiple event horizons, we show that the proposed method remains applicable even in such scenarios.

The Theory of Everything seeks to unify all fundamental forces of nature, including quantum gravity, into a single theoretical framework. This theory would be defined internally using a set of axioms, and this paper proposes a set of axioms for any such theory. Furthermore, for such a theory, all scientific truth would be defined internally as consequences derivable from the rules of such a theory. This paper then examines the implications of Tarski's undefinability theorem on scientific truths derived from such axioms. We demonstrate that Tarski's theorem imposes limitations on any such formal system . However, we also argue that the Lucas-Penrose argument suggests that non-algorithmic understanding can transcend these formal limitations.

We attempt to construct a (two-dimensional) statistical mechanics description of the scenario in which the experiment in [T. Westphal et al., Nature 591, 225 (2021)] was made. It includes two masses that, simultaneously, (1) interact classically via the Newton gravitation and (2) harmonically vibrate. Within the strictures of Gibbs canonical ensemble at the temperature T, our treatment is exact.