Thick Domain Walls Intersecting a Black Hole

We discuss the gravitationally interacting system of a thick domain wall and a black hole. We numerically solve the scalar field equation in the Schwarzschild spacetime and show that there exist scalar field configurations representing thick domain walls intersecting the black hole.Comment: 14 pages, 8 figure

CaCO₃ mineralization in polymer composites with cellulose nanocrystals providing a chiral nematic mesomorphic structure

CaCO₃ mineralization was carried out using cellulose nanocrystal (CNC)/polymer composites wherein a chiral nematic structure of CNC assembly was immobilized in advance via a polymerization process of the precursory aqueous CNC/vinyl monomer lyotropics (7–11 wt% CNC in feed). Two series of polymer composites were prepared: CNC/poly(2-hydroxyethyl methacrylate) (PHEMA) and CNC/poly(2-hydroxyethyl methacrylate-co-acrylic acid) (P(HEMA-co-AA), HEMA:AA = 95:5–70:30 in mol). The mineralization was allowed to proceed solely by soaking the composite films in a salt solution containing Ca²⁺ and HCO₃− under a low-basic condition (pH ≤ 9). Polymorphism of CaCO3 deposited inside the films was examined by X-ray diffractometry as a function of the soaking time (1–5 day) and also of the matrix composition. In the CNC/PHEMA series, the polymorphic form changed from amorphous calcium carbonate (ACC) (1-day soaking) to metastable crystalline vaterite (3-day soaking) and then to a mixture of vaterite and aragonite (5-day soaking). In the mineralization of the CNC/P(HEMA-co-AA) series, the formation of stable calcite was prominent besides minor appearance of vaterite. It was deduced that the mesofiller CNC and the AA unit in the vinyl polymer, both bearing an anionic group (-SO₃− or -COO−), contributed to capturing Ca²⁺ to facilitate the CaCO₃ deposition in the swollen film matrix. The pre-invested chiral nematic organization was kept in any of the mineralized films (dried); however, the helical pitch was appreciably reduced relative to that observed before the mineralization, attributable to the increase of ionic strength in the CNCs' surroundings accompanied by the wet process. Thermogravimetry showed that the mineralization definitely improved the thermal performance (heat/flame resistance) of the mesomorphic order-retaining CNC/polymer composites

Tense Shift in Chaucer’s Narrative Text: With Special Regard to the Synchronization of Subjectivity and Phenomena

In Chaucer’s narrative text events usually expressed in the past tense in modern English are more often than not expressed in the present tense. The speaker or subjectivity of cognition is flexible enough to depart from the speech time (absolute present time) to be close to the phenomena in the past, which tends to promote the present tense. Tense shift analysis in Chaucer has so far been limited to the historical present and tense agreement in indirect speech with little systematic investigation. Chaucer’s tense shift is similar to the tense shift from the past to the present in Japanese which is derivable from I-mode. The aim of this paper is to reconsider Chaucer’s tense shift based on this Japanese I-mode. We set up two research aims 1) to describe tense shift systematically; 2) to make clear factors to promote tense shift. We concluded that tense shift in Chaucer’s narrative text occurs through wide ranging units: one metrical line, one simple sentence, one compound sentence, one complex sentence (main clause + nominal clause, adjectival clause, or adverbial clause), and a stretch of discourse comprising dozens of sentences, and that this repeated shift is due to the synchronization between the subjectivity of cognition or the conceptualizer and the phenomena with added subfactors of orality and generic/gnomic implications. The interpretation of this remains to be further considered

Gravitational Radiation from Cylindrical Naked Singularity

We construct an approximate solution which describes the gravitational emission from a naked singularity formed by the gravitational collapse of a cylindrical thick shell composed of dust. The assumed situation is that the collapsing speed of the dust is very large. In this situation, the metric variables are obtained approximately by a kind of linear perturbation analysis in the background Morgan solution which describes the motion of cylindrical null dust. The most important problem in this study is what boundary conditions for metric and matter variables should be imposed at the naked singularity. We find a boundary condition that all the metric and matter variables are everywhere finite at least up to the first order approximation. This implies that the spacetime singularity formed by this high-speed dust collapse is very similar to that formed by the null dust and thus the gravitational emission from a naked singularity formed by the cylindrical dust collapse can be gentle.Comment: 20 pages, 1 figur

Relativistic Gravitational Collapse of a Cylindrical Shell of Dust

The gravitational collapse of a thick cylindrical shell of dust matter is investigated. It is found that a spacetime singularity forms on the symmetry axis and that it is necessarily naked, i.e., observable in principle. We propose a physically reasonable boundary condition at this naked singularity to construct the solution including its causal future. This boundary condition enables us to construct the unique continuation of spacetime beyond the naked singularity and ensures that the dust shell passes through the naked singularity. When the cylindrical shell leaves its symmetry axis away, the naked singularity disappears, and regularity is recovered. We construct numerical solutions with this feature. This result implies that the gravity produced by a thick cylindrical shell of dust is too weak to bind the shell even if it engenders the formation of a curvature singularity which is so strong as to satisfy the limiting focusing condition. For this reason, this naked singularity is very weak in the extended spacetime; the metric tensor is $C^{1-}$ even at the naked singularity, and the extended spacetime is complete for almost all geodesics. This feature is also seen for singular hypersurfaces. Such an extended spacetime can be regarded as phenomenological in the sense that it is valid if the relevant microphysics length scale is sufficiently small compared to the scale of interest.Comment: 32 pages, 6 figure

Textual Variations and Readings among the Manuscripts and Editions of The Canterbury Tales: With Special Reference to The Knight’s Tale

This is a revised version of the paper presented at the 20th congress of the New Chaucer Society at Queen Mary University of London on 12 July 2016. This research was supported by Grant-in-Aid for Scientific Research (C) (Grant Number 15K02304) from the Japan Society for the Promotion of Science