Gravitating tensor monopole in a Lorentz-violating field theory

We present a solution of the coupled Einstein and rank-two antisymmetric tensor field equations where Lorentz symmetry is spontaneously broken, and we discuss its observational signatures. Especially, the deflection angles have important qualitative differences between tensor and scalar monopoles. If a monopole were to be detected, it would be discriminated whether or not to correspond to a tensor one. This phenomenon might open up new direction in the search of Lorentz violation with future astrophysical observations.Comment: 5 pages, 4 figure

Interaction Between Supernova Remnant G22.7-0.2 And The Ambient Molecular Clouds

We have carried out 12CO (J=1-0 and 2-1), 13CO (J=1-0), and C18O (J=1-0) observations in the direction of the supernova remnant (SNR) G22.7-0.2. A filamentary molecular gas structure, which is likely part of a larger molecular complex with VLSR~75-79 km/s, is detected and is found to surround the southern boundary of the remnant. In particular, the high-velocity wing (77-110 km/s) in the 12CO (J=1-0 and J=2-1) emission shows convincing evidence of the interaction between SNR G22.7-0.2 and the 75-79 km/s molecular clouds (MCs). Spectra with redshifted profiles, a signature of shocked molecular gas, are seen in the southeastern boundary of the remnant. The association between the remnant and the 77 km/s MCs places the remnant at the near distance of 4.0-4.8 kpc, which agrees with a location on the Scutum-Crux arm. We suggest that SNR G22.7-0.2, SNR W41, and HII region G022.760-0.485 are at the same distance and are associated with GMC G23.0-0.4.Comment: 9 pages, 9 figures, 3 tables, accepted for publication in Ap

Corpus in Foreign Language Teaching and Research

Corpus-based language research has been long prospered since the middle of last century. Corpus is therefore frequently used in foreign language (mostly English) teaching and research due to the fundamental principles of modern Corpus Linguistics along with the colorful resources of word-banks and the corresponding tools, especially in western countries. In China, the related literature found its way from introducing the foreign researches to our own practice into this field. As a conclusion, corpus and Corpus Linguistics can be closely connected with and widely applied in foreign language teaching and research with a predictable bright future. Keywords: corpus, Corpus Linguistics, foreign language teaching and research Résumé Le moyen de recherches sur le corpus a connu un développement rapide depuis le milieu du siècle précédent et a atteint la maturité aujourd’hui. En raison de l’importance de la linguistique de corpus et de la méthode de recherches sur le corppus, et étant donné ses ressources riches ainsi que les facilités apportées par les outils de recherche, le corpus est appliquée amplement dans les recherches linguistiques notamment dans celles de l’anglais. A l’étranger, l’étude de la linguistique de corpus a débuté tôt et a donné beaucoup de fruits ; le travail du milieu des langues étrangères chinois dans ce domaine a commencé par la présentation du corpus étranger et sa situation d’étude, et puis procède à des applications pratiques. En somme, il existe des relations étroites et diverses entre le corpus et les recherches de l’enseignement-apprentissage des langues étrangères, et les recherches de l’enseignement-apprentissage des langues étrangères basant sur le corpus présente une bonne perspective. Mots-clés: corpus, linguistique de corpus, recherches de l’enseignement-apprentissage des langues étrangères 摘 要 語料庫研究方法自上個世紀中葉以來迅速發展，到今天已空前繁榮。由於語料庫語言學和語料庫研究方法的重要性，又由於豐富的語料庫資源及檢索工具提供了實踐的可能和便利，語料庫被廣泛應用於語言研究特別是英語教學研究中。國外語料庫語言學研究起步早，成果多；我國外語界在這方面的工作主要是從介紹國外語料庫及其研究現狀開始，然後進行一些應用實踐。總之，語料庫與外語教學研究有著緊密的、多層面的關係，基於語料庫的外語教學研究大有可為、前景廣闊。關鍵詞：語料庫；語料庫語言學；外語教學研

Alternative mechanism of avoiding the big rip or little rip for a scalar phantom field

Depending on the choice of its potential, the scalar phantom field $\phi$ (the equation of state parameter $w<-1$) leads to various catastrophic fates of the universe including big rip, little rip and other future singularity. For example, big rip results from the evolution of the phantom field with an exponential potential and little rip stems from a quadratic potential in general relativity (GR). By choosing the same potential as in GR, we suggest a new mechanism to avoid these unexpected fates (big and little rip) in the inverse-\textit{R} gravity. As a pedagogical illustration, we give an exact solution where phantom field leads to a power-law evolution of the scale factor in an exponential type potential. We also find the sufficient condition for a universe in which the equation of state parameter crosses $w=-1$ divide. The phantom field with different potentials, including quadratic, cubic, quantic, exponential and logarithmic potentials are studied via numerical calculation in the inverse-\textit{R} gravity with $R^{2}$ correction. The singularity is avoidable under all these potentials. Hence, we conclude that the avoidance of big or little rip is hardly dependent on special potential.Comment: 9 pages,6 figure