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1.
考虑温度效应,运用改写的能自发破缺产生整体宇宙弦的标量场在有限温度下的拉氏密度,求解了整体宇宙弦核外的引力场方程,对零温理论中的结果作了修正,进而讨论弦核外引力场的性质。  相似文献   

2.
本文讨论了有限温度整体宇宙弦的引力场及其物质的吸积,以及在有限温度运动整体宇宙弦对吸积物质的影响其结果与零温整体宇宙弦的性质有区别。  相似文献   

3.
考虑静质量为零的中微子背景,探讨了背景场对整体宇宙弦核外引力场的影响,采用通常的静态柱对称度规,运用共动Cartan标架场方法求解弯曲时空中旋量场的Dirac方程进而求出旋量场的能动张量,将其能动张量与宇宙弦(核外)的能动张量叠加,求出了中微子场背景下整体宇宙弦为源的Einstein方程的线性近似解,其度规为通常的结果加上旋量场的贡献,即在通常对数排斥势的基础上获得了一项附加的对数引力势的修正,对  相似文献   

4.
在非线性二次引力理论中,探讨了整体宇宙弦的引力场,与爱因斯坦引力理论的结果相比较,其度规获得了一个相当于长程牛顿势的修正,表明在远处有一高阶的吸引力。并在此基础上讨论了运动的整体宇宙弦的吸积问题,弦尾部的吸积效应也作了相应的修正。  相似文献   

5.
用相对论平均场(RMF)理论系统地计算了A<40的原子核的基态性质,讨论了轻核的均方根半径,给出了原子核均方根半径对原子核平均结合能及同位旋的依赖关系.在理论计算与实验数据的基础上,提出了一组唯象公式,用于描述A<40的所有原子核的质子与中子均方根半径.该公式考虑了原子核的平均结合能,分离能及同位旋效应,不仅可以很好地符合稳定核的均方根半径,也能符合远离(稳定线的原子核的半径,包括有晕结构的核.  相似文献   

6.
本文研究了宇宙弦中超导电流的磁效应以及度规函数和超导电流之间的关系。研究表明:超导宇宙弦外部时空相当于一种磁化率为μ(r)的磁介质;当光线经过超导宇宙弦时,产生偏折。同时,在弱场近似下,也讨论了超导宇宙弦的引力场度规和当光线经过宇宙弦时所产生的偏折角。  相似文献   

7.
相对论是现代科学的重要基础,是物理学通向宇宙的桥梁.对爱因斯坦建立广义相对论的过程进行了分析,引力问题是自然界乃至整个宇宙世界的一个基本问题.引力场是一种矢量场,广义相对论对引力问题的描述是非常有效的.通过对引力场的分析,得到了引力场的高斯定理,讨论了引力场的环路定理.通过方程,求出了引力场中的势函数,探讨了引力场的基本性质.  相似文献   

8.
通过考虑引力子的自旋,重新给出了引力场的高斯定理.由高斯定理出发,得到了球对称引力场的引力势和引力势能的计算式.对于物质密度为E指数的情况,计算了球对称天体的引力势和引力势能.在特殊情况下,研究了球对称天体的质量和引力势能与天体半径的关系.  相似文献   

9.
为了明确地研究引力场和引力波的性质,提出了一种假设:电中性运动质量流、运动物体或变化的引力场可以激发一种场,这种场可以对在其中运动的物体施加力,这种场的变化可以激发引力场.之后提出了这种场与引力场的关系方程组,并且从这个方程组出发推导出波动方程,波中的三个矢量:引力场、这个新场和波传播方向矢量满足左手定则.此与电磁波中的电场矢量、磁场矢量和电磁波的传播方向满足右手定则形成明显的对照.  相似文献   

10.
通过2维和4维温度弦模型研究暗能量玻色子星的质量和物态参量,推导高亏格黎曼面上的玻色弦自由能,获得引力场方程和dilaton暗能量场方程的表达式,给出玻色子星的质量和物态参量的推导过程.另外,还分析和比较了不同时空中计算结果所具有的特点.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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