16 papers
Recovering What Breaks in a Trapped-Ion Quantum Simulation of a Lattice Gauge Theory
Hassan Ugail
A recent trapped-ion experiment realised a lattice gauge theory with the gauge field in the internal states of the ions and bosonic matter in their vibrations. We showed earlier th…
Predicting Noise in a Trapped-ion Quantum Simulation of a Lattice Gauge Theory
Hassan Ugail
A recent trapped-ion experiment realised a lattice gauge theory in which the internal states of the ions carry the gauge field and their vibrations carry bosonic matter. In that ex…
Smooth Curves from Curvature-Driven Subdivision
Hassan Ugail
We introduce and analyse an interpolatory subdivision scheme in which each inserted point is defined by a curvature-profile model rather than by an affine combination of its neighb…
Adaptive Interpolatory Curve Subdivision with Learned Local Angles
Hassan Ugail, Newton Howard
Curve subdivision is pivotal in computer graphics for generating smooth geometric objects from control polygons. Interpolatory subdivision is especially attractive because the refi…
A Heisenberg Lift Descriptor for Order Sensitive Online Handwriting Recognition
Hassan Ugail, Newton Howard
Online handwriting recognition systems typically represent pen trajectories through fixed-length Euclidean shape descriptors that capture the spatial outline of each stroke, but ar…
Proximity-Preserving Neural Subdivision
Hassan Ugail
Classical subdivision schemes are widely used because they are local, repeatable, and analytically tractable. A single stencil defines the entire refinement rule, and the behaviour…
Reliable Weyl Diagnostics for an Inhomogeneous Universe in Numerical Relativity
Hassan Ugail
The electric and magnetic parts of the Weyl tensor provide a geometric diagnostic for describing the local gravitational structure of an inhomogeneous universe, and they allow us t…
A Heisenberg Subdivision Scheme with Central Smoothness Loss
Hassan Ugail, Alfonso Carriazo
We introduce an interpolatory subdivision scheme for control polygons that take values in the three-dimensional Heisenberg group, the simplest noncommutative model geometry. The sc…
A Coherence Law for Trainability in Noisy Equivariant Quantum Neural Networks
Hassan Ugail, Newton Howard
Symmetry provides a quantum neural network structure, but on its own it does not keep the network trainable once noise is present. We ask which physical quantity decides whether th…
Geometric Phase-Space Structure in Cosmological Solutions of Einstein's Field Equations
Hassan Ugail
Einstein field equations allow cosmological dynamics to depart from the Friedmann-Lemaitre-Robertson-Walker (FLRW) idealisation in several physically different ways. Matter may bec…
Training Deep Visual Networks Beyond Loss and Accuracy Through a Dynamical Systems Approach
Hai La Quang, Hassan Ugail, Newton Howard +3
Deep visual recognition models are usually trained and evaluated using metrics such as loss and accuracy. While these measures show whether a model is improving, they reveal very l…
Biharmonic Subdivision on Riemannian Manifolds
Hassan Ugail, Newton Howard
This paper introduces a biharmonic interpolatory subdivision framework on Riemannian manifolds. In the Euclidean setting, the six-point Deslauriers-Dubuc stencil is characterised a…
A Neural Tension Operator for Curve Subdivision across Constant Curvature Geometries
Hassan Ugail, Newton Howard
Interpolatory subdivision schemes generate smooth curves from piecewise-linear control polygons by repeatedly inserting new vertices. Classical schemes rely on a single global tens…
Handcrafted Feature-Assisted One-Class Learning for Artist Authentication in Historical Drawings
Hassan Ugail, Jan Ritch-Frel, Irina Matuzava
Authentication and attribution of works on paper remain persistent challenges in cultural heritage, particularly when the available reference corpus is small and stylistic cues are…
Dynamical Systems Analysis Reveals Functional Regimes in Large Language Models
Hassan Ugail, Newton Howard
Large language models perform text generation through high-dimensional internal dynamics, yet the temporal organisation of these dynamics remains poorly understood. Most interpreta…
Quantifying the Dynamics of Consciousness using Hierarchical Integration, Organised Complexity and Metastability
Hassan Ugail, Newton Howard
Quantifying the neural signatures of consciousness remains a major challenge in neuroscience and AI. Although many theories link consciousness to rich, multiscale, and flexible neu…