Resonant Configurations in Scalar Field Theories: Can (Some) Oscillons Live Forever?

We investigate the longevity of oscillons numerically, paying particular attention to radially-symmetric oscillons that have been conjectured to have an infinitely-long lifetime. In two spatial dimensions, oscillons have not been seen to decay. In three spatial dimensions, specific initial Gaussian configurations seem to lead to oscillons with spikes in lifetime that have been conjectured to be infinite. We study such ``resonant'' oscillons in two and three spatial dimensions, applying two tests to study their longevity: parametric resonance and virialization. Without offering a formal proof, our numerical results, within their precision, offer support for the conjecture that, in both dimensions, resonant oscillons may be infinitely long-lived.Comment: 15 pages, 14 figure. Version accepted for publication in Physical Review D. Two new figures, some comments added for clarificatio

Resonant configurations in scalar field theories: Can some oscillons live forever?

We investigate the longevity of oscillons numerically, paying particular attention to radially symmetric oscillons that have been conjectured to have an infinitely long lifetime. In two spatial dimensions, oscillons have not been seen to decay. In three spatial dimensions, specific initial Gaussian configurations seem to lead to oscillons with spikes in lifetime that have been conjectured to be infinite. We study such resonant oscillons in two and three spatial dimensions, applying two tests to study their longevity: Parametric resonance and virialization. Without offering a formal proof, our numerical results offer support for the conjecture that, in both dimensions, resonant oscillons may be infinitely long lived

Bonded discrete element simulations of sea ice with non-local failure: Applications to Nares Strait

The discrete element method (DEM) can provide detailed descriptions of sea ice dynamics that explicitly model floes and discontinuities in the ice, which can be challenging to represent accurately with current models. However, floe-scale stresses that inform lead formation in sea ice are difficult to calculate in current DEM implementations. In this paper, we use the ParticLS software library to develop a DEM that models the sea ice as a collection of discrete rigid particles that are initially bonded together using a cohesive beam model that approximates the response of an Euler-Bernoulli beam located between particle centroids. Ice fracture and lead formation are determined based on the value of a non-local Cauchy stress state around each particle and a Mohr-Coulomb fracture model. Therefore, large ice floes are modeled as continuous objects made up of many bonded particles that can interact with each other, deform, and fracture. We generate particle configurations by discretizing the ice in MODIS satellite imagery into polygonal floes that fill the observed ice shape and extent. The model is tested on ice advecting through an idealized channel and through Nares Strait. The results indicate that the bonded DEM model is capable of qualitatively capturing the dynamic sea ice patterns through constrictions such as ice bridges, arch kinematic features, and lead formation. In addition, we apply spatial and temporal scaling analyses to illustrate the model's ability to capture heterogeneity and intermittency in the simulated ice deformation

Kaluza's Law and Secondary Stress

Kaluza’s law is a proposed restriction in the metre of Beowulf against the resolution of light-heavy sequences: words like cyning ‘king’ can only resolve and count as the equivalent of a single heavy syllable under more restricted circumstances than can words such as wudu ‘wood’. There has been debate about how to define these ‘restricted circumstances’, with many investigators claiming that this limitation holds only under ‘secondary stress’(sometimes broadened to include subordinated stress in general). This article reviews the operation of Kaluza’s law in Beowulf, arguing that the correct conditioning is the position immediately following a heavy syllable. The level of stress carried by the (non-)resolving sequence is irrelevant. A phonological explanation for this restriction may be that the resolution ideally produces bimoraic (light-light) units; accordingly, resolution of light-heavy sequences, which is anomalous from a typological and phonological perspective, is only permitted in word-initial position, or in metrical equivalents