Monte Carlo study of Schwinger model without the sign problem

Monte Carlo study of the Schwinger model (quantum electrodynamics in one spatial dimension) with a topological $\theta$ term is very difficult due to the sign problem in the conventional lattice formulation. In this paper, we point out that this problem can be circumvented by utilizing the lattice formulation of the bosonized Schwinger model, initially invented by Bender et al. in 1985. After conducting a detailed review of their lattice formulation, we explicitly validate its correctness through detailed comparisons with analytical and previous numerical results at $\theta = 0$. We also obtain the $\theta$ dependence of the chiral condensate and successfully reproduce the mass perturbation result for small fermion masses $m / g \lesssim 0.125$. As an application, we perform a precise calculation of the string tension and quantitatively reveal the confining properties in the Schwigner model at finite temperature and $\theta$ region for the first time. In particular, we find that the string tension is negative for noninteger probe charges around $\theta = \pi$ at low temperatures.Comment: 17 pages, 7 figures, to appear from JHE

Investigation of the relationship with infrasonic wave and auroral activity in the polar region

The Tenth Symposium on Polar Science/Ordinary sessions: [OS] Space and upper atmospheric sciences, Wed. 4 Dec. /Entrance Hall (1st floor) at National Institute of Polar Research (NIPR

Functional organisation of anterior thoracic stretch receptors in the deep-sea isopod Bathynomus doederleini: Behavioural, morphological and physiological studies

The relationship between segmental mobility and the organisation of thoracic stretch receptors was examined in the deep-sea isopod Bathynomus doederleini, which shows a developed adaptive behaviour during digging. The movements of segments during digging were analysed from video recordings, which showed that a large excursion occurred in the anterior thoracic segments. Dyefills of axons revealed four types of thoracic stretch receptor (TSR): an N-cell type (TSR-1), a differentiated Ncell type (TSR-2), a muscle receptor organ (MRO)-type with a long, single receptor muscle (TSR-3) and an MROtype with a short, single receptor muscle (TSR-4 to TSR-7). Physiologically, TSR-1 and TSR-2 are tonic-type stretch receptors. TSR-3 to TSR-7 show two kinds of stretchactivated responses, a tonic response and a phasico-tonic response in which responses are maintained as long as the stretch stimulus is delivered. Both TSR-2, with a long muscle strand, and TSR-3, with a single, long receptor muscle, have a wide dynamic range in their stretchactivated response. In addition, TSR-2 is controlled by an intersegmental inhibitory reflex from TSR-3. These results suggest that, although TSR-1 has no receptor muscle and TSR-2 has a less-differentiated receptor-like muscle, they are fully functional position detectors of segmental movements, as are the MRO-type receptors TSR-3 to TSR-7.</p

堆積物重力流ベッドフォームの形成条件

京都大学新制・課程博士博士(理学)甲第23017号理博第4694号新制||理||1673(附属図書館)京都大学大学院理学研究科地球惑星科学専攻(主査)准教授 成瀬 元, 准教授 堤 昭人, 教授 生形 貴男学位規則第4条第1項該当Doctor of ScienceKyoto UniversityDGA

モンテカルロ法によるシュウィンガー模型の有限温度有限シータ領域の解析

京都大学新制・課程博士博士(理学)甲第25105号理博第5012号京都大学大学院理学研究科物理学・宇宙物理学専攻(主査)准教授 菅沼 秀夫, 准教授 福間 將文, 教授 橋本 幸士学位規則第4条第1項該当Doctor of ScienceKyoto UniversityDFA