Wikidata is great for asking weird questions like "Who is the most famous child of a librari... more Wikidata is great for asking weird questions like "Who is the most famous child of a librarian?" (the answer will surprise you). But what use are all the external identifiers that make up 90% of the database? I'll show you how to use them to navigate the web.<br> Say you're on a webpage about a particular thing ("entity"). Click on the browser extension Entity Explosion to get information about that entity (from the URL alone!), and an explosion of links to other sites about that same entity. The data provided is sourced live from Wikidata - the Rosetta Stone of the internet - and can be retrieved in any language. <br> We'll browse around some topics of your choice, to see how powerful you can be with a pinch of Wikidata added to your browser.
Novel crystal structures in binary atomic mixtures arise when the attractive well is wide enough ... more Novel crystal structures in binary atomic mixtures arise when the attractive well is wide enough to allow double occupancy by small particles. The resulting crystals consist of ordered packings of self assembled linear structures comprised of a cylindrical tube of large particles enclosing a close packed core of small particles that corresponds to a stacking of overlapping icosahedra. We show that the stability of these structures depends on two essential features of the spherically symmetric pairwise interactions: (i) a radius ratio between 0.414 and 0.588, and (ii) a width w of the attractive well in the interaction between unlike particles that satisfies w > σSS where σSS is the diameter of the small particle.
A key property of glass forming alloys, the anomalously small volume difference with respect to t... more A key property of glass forming alloys, the anomalously small volume difference with respect to the crystal, is shown to arise as a direct consequence of the soft repulsive potentials between metals. This feature of the inter-atomic potential is demonstrated to be responsible for a significant component of the glass forming ability of alloys due to the decrease in the enthalpy of fusion and the associated depression of the freezing point.
Simulation studies of the atomic shear stress in the local potential energy minima (inherent stru... more Simulation studies of the atomic shear stress in the local potential energy minima (inherent structures) are reported for binary liquid mixtures in 2D and 3D. These inherent structure stresses are fundamental to slow stress relaxation and high viscosity in supercooled liquids. We find that the atomic shear stress in the inherent structures (IS's) of both liquids at rest exhibits slowly decaying anisotropic correlations. We show that the stress correlations contribute significantly to the variance of the total shear stress of the IS configurations and consider the origins of the anisotropy and spatial extent of the stress correlations.
Proceedings of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences, 2004
We study the effects of oversized solute atoms on the diffusion of clusters of self-interstitial ... more We study the effects of oversized solute atoms on the diffusion of clusters of self-interstitial atoms produced in metals by high-energy irradiation. We use kinetic Monte Carlo (KMC) simulations in model body-centred cubic iron, and include elastic interactions between the defects. We show that elastic repulsion between solute atoms and the clusters can confine the latter to one-dimensional segments. The
Evidence of a special chiral nematic phase is provided using numerical simulation and Onsager the... more Evidence of a special chiral nematic phase is provided using numerical simulation and Onsager theory for systems of hard helical particles. This phase appears at the high density end of the nematic phase, when helices are well aligned, and is characterized by the C2 symmetry axes of the helices spiraling around the nematic director with periodicity equal to the particle pitch. This coupling between translational and rotational degrees of freedom allows a more efficient packing and hence an increase of translational entropy. Suitable order parameters and correlation functions are introduced to identify this screw-like phase, whose main features are then studied as a function of radius and pitch of the helical particles. Our study highlights the physical mechanism underlying a similar ordering observed in colloidal helical flagella [E. Barry, Z. Hensel, Z. Dogic, M. Shribak, and R. Oldenbourg, Phys. Rev. Lett. 96, 018305 (2006)] and raises the question of whether it could be observed ...
Wikidata is great for asking weird questions like "Who is the most famous child of a librari... more Wikidata is great for asking weird questions like "Who is the most famous child of a librarian?" (the answer will surprise you). But what use are all the external identifiers that make up 90% of the database? I'll show you how to use them to navigate the web.<br> Say you're on a webpage about a particular thing ("entity"). Click on the browser extension Entity Explosion to get information about that entity (from the URL alone!), and an explosion of links to other sites about that same entity. The data provided is sourced live from Wikidata - the Rosetta Stone of the internet - and can be retrieved in any language. <br> We'll browse around some topics of your choice, to see how powerful you can be with a pinch of Wikidata added to your browser.
Novel crystal structures in binary atomic mixtures arise when the attractive well is wide enough ... more Novel crystal structures in binary atomic mixtures arise when the attractive well is wide enough to allow double occupancy by small particles. The resulting crystals consist of ordered packings of self assembled linear structures comprised of a cylindrical tube of large particles enclosing a close packed core of small particles that corresponds to a stacking of overlapping icosahedra. We show that the stability of these structures depends on two essential features of the spherically symmetric pairwise interactions: (i) a radius ratio between 0.414 and 0.588, and (ii) a width w of the attractive well in the interaction between unlike particles that satisfies w > σSS where σSS is the diameter of the small particle.
A key property of glass forming alloys, the anomalously small volume difference with respect to t... more A key property of glass forming alloys, the anomalously small volume difference with respect to the crystal, is shown to arise as a direct consequence of the soft repulsive potentials between metals. This feature of the inter-atomic potential is demonstrated to be responsible for a significant component of the glass forming ability of alloys due to the decrease in the enthalpy of fusion and the associated depression of the freezing point.
Simulation studies of the atomic shear stress in the local potential energy minima (inherent stru... more Simulation studies of the atomic shear stress in the local potential energy minima (inherent structures) are reported for binary liquid mixtures in 2D and 3D. These inherent structure stresses are fundamental to slow stress relaxation and high viscosity in supercooled liquids. We find that the atomic shear stress in the inherent structures (IS's) of both liquids at rest exhibits slowly decaying anisotropic correlations. We show that the stress correlations contribute significantly to the variance of the total shear stress of the IS configurations and consider the origins of the anisotropy and spatial extent of the stress correlations.
Proceedings of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences, 2004
We study the effects of oversized solute atoms on the diffusion of clusters of self-interstitial ... more We study the effects of oversized solute atoms on the diffusion of clusters of self-interstitial atoms produced in metals by high-energy irradiation. We use kinetic Monte Carlo (KMC) simulations in model body-centred cubic iron, and include elastic interactions between the defects. We show that elastic repulsion between solute atoms and the clusters can confine the latter to one-dimensional segments. The
Evidence of a special chiral nematic phase is provided using numerical simulation and Onsager the... more Evidence of a special chiral nematic phase is provided using numerical simulation and Onsager theory for systems of hard helical particles. This phase appears at the high density end of the nematic phase, when helices are well aligned, and is characterized by the C2 symmetry axes of the helices spiraling around the nematic director with periodicity equal to the particle pitch. This coupling between translational and rotational degrees of freedom allows a more efficient packing and hence an increase of translational entropy. Suitable order parameters and correlation functions are introduced to identify this screw-like phase, whose main features are then studied as a function of radius and pitch of the helical particles. Our study highlights the physical mechanism underlying a similar ordering observed in colloidal helical flagella [E. Barry, Z. Hensel, Z. Dogic, M. Shribak, and R. Oldenbourg, Phys. Rev. Lett. 96, 018305 (2006)] and raises the question of whether it could be observed ...
Uploads
Papers by Toby Hudson