Einstein-Bumblebee引力理论中的Kerr-Sen-like黑洞玻色子隧穿辐射

Lorentz-breaking理论不仅对弯曲时空背景有影响,而且对于在弯曲时空中的玻色子和费米子的动力学方程都有一定的修正.因此,我们需要在不同的黑洞时空中对玻色子和费米子的量子隧穿辐射进行适当的修正.从而得到经过Lorentz-breaking理论修正后的黑洞Hawking温度等物理量的新表达式及其物理意义.本文根据Einstein-Bumblebee引力理论中得到的Kerr-Sen-like (KSL)黑洞时空度规,在标量场作用量中引入aether-like场矢量修正项和弯曲时空中的d’Alembert算符并应用弯曲时空中的变分原理,研究了此时空度规中的Lorentz-breaking修正项及KSL时空中自旋为零的含有Lorentz-breaking修正项的玻色子动力学方程的新形式.通过正确选择与KSL时空度规相对应的aether-like场矢量,求解修正的玻色子动力学方程,得到了修正的量子隧穿率,并在此基础上研究了含有Lorentz-breaking修正项的此黑洞的Hawking温度和Bekenstein-Hawking熵.此外,还研究了Lorentz-breaking效应对玻...     

洛仑兹破缺标量场的霍金隧穿辐射

把洛仑兹破缺的标量场方程推广到弯曲时空中,并通过Aether-like项对标量场方程进行修正,该项所产生的效应也会影响到黑洞时空视界附近处的物理效应.接着,进一步在半经典近似下得到了修正的Hamilton-Jacobi方程,然后用这一修正的Hamilton-Jacobi方程研究了史瓦西黑洞的隧穿辐射特征,并讨论了洛仑兹破缺对黑洞霍金辐射和黑洞熵的影响.结果表明,u~α=δ_t~αu~t,δ_r~αu~r形式的Aether-like项的效应可能使黑洞温度增加,而黑洞熵降低.该工作可以帮助我们更深刻地理解弯曲时空中的洛仑兹破缺效应的物理性质.     

强激光等离子体中的自由电子波函数

借助激光等离子体的光学度规,严格求解了弯曲时空中的狄喇克方程,得到了强激光等离子体中的自由电子波函数。当激光场为零时,该波函数自然地过渡到相对论的自由电子波函数。简单地讨论了该波函数可能的应用。 关键词：     

类时曲线上矢量场的时空转动

详细讨论了弯曲时空中类时曲线上矢量场的转动，以弥补有关专著的不足。     

史瓦西时空中自由粒子的运动方程

直接求解史瓦西时空中自由粒子的测地线方程,得出粒子运动方程的一般常见形式.此方法与一般教材中根据史瓦西度规的静态球对称性以及四速归一条件得出的运动方程完全相同.此方法物理意义更清晰、明确,同时对理解弯曲时空中的测地线方程具有重要意义.     

广义不确定关系与黑洞附近的热力学量

利用广义不确定关系修正的态密度计算了一般球对称静态黑洞附近无质量共形不变标量场、中微子场、电磁场、无质量Rarita-Schwinger场和引力场的热力学量.结果表明，黑洞附近的热力学量不仅依赖于黑洞的特征，还依赖于粒子的自旋和最小距离的尺度. 关键词： 广义不确定关系 一般球对称静态黑洞 热力学量     

弯曲空间的SU(N)规范理论的磁单极子与双子解

(一) 自′t Hooft得到SU(2)规范场的经典磁单极子解以来,在弯曲空间中的SU(2)规范场的解也有了一系列的研究,结果表明静态中心球对称解的弯曲空间度规与U(1)场的Reissner-Nordstrom度规相同,只不过把e~2换成SU(2)的规范荷Q~2与其对偶荷(磁荷)g_(2)~2的平方和O~2+g_(2)~2.Yasskin较普遍地研究了Einstein-Yang-Mills场耦合方程的求解问题,提出它们可由弯曲空间电磁场的解来构成.但构成时引入的参量β~p的意义不明确.     

Dirac粒子的Hawking蒸发

在Kerr背景时空中求解Dirac方程是一个长期没有解决的问题。1976年Chandrasekhar成功地找到了Kerr背景时空中静止质量不为零的Dirac方程的退耦和分离变量的量子方程。本文在此基础上,在近似极端Kerr黑洞的事件视界附近找到了静止质量不为零的Dirac方程的解,并成功地导出了Hawking热谱公式,从而解决了Dirac粒子在Kerr黑洞的Hawking蒸发问题。 关键词：     

引力波背景下的电磁波

本文首先介绍了激光干涉引力波探测实验原理教学的时空图方法,紧接着对引力波背景下一种具有简单然而非平庸时空轮廓的电磁场的波动方程进行了化简并求出了其解析解,最后利用所得解对激光干涉引力波探测实验中测地光子近似的有效性进行了定量的评估和分析。我们的结果对激光干涉引力波探测原理和弯曲时空中麦克斯韦方程组及电磁波理论的教学有积极的探讨价值。     

新型三角芯抗弯曲大模场面积光子晶体光纤

提出了一种新型三角芯抗弯曲大模场面积光子晶体光纤.该结构采用单一尺寸的圆形空气孔, 降低了制作难度.在波长1.064 μm处, 在平直状态和弯曲半径为30 cm时, 模场面积分别为1386 μm²和1153 μm², 弯曲带来的模场面积减少量仅为16.85%. 当弯曲半径为30 cm时, 基模的损耗为0.087 dB/m, 二阶模的损耗大于1.5 dB/m, 大的损耗差有效保证了光纤单模运转.此外, 弯曲半径30 cm时, 弯曲方向角扩展至±180°, 光纤弯曲不再受弯曲方向的限制. 所设计的光纤结构具有大模场面积、小的模场面积减少量、 低的弯曲损耗以及低的弯曲方向敏感度等优势, 为小型化、集成化高功率激光传输及光纤激光器和放大器的研究奠定了基础. 关键词： 光子晶体光纤 大模场面积 抗弯曲 弯曲方向角     

Dirac equation in (1+1)-dimensional curved space-time

The Dirac equation in (1+1)-dimensional curved space-time is solved explicitly for the spatially flat Robertson-Walker space-time and the cigar metric considered by Witten.     

A review of super riemannian space-time using differential forms

We analyse the content of curved super space-time, which consists of points labelled by four ordinary space-time variables and a set of anti-commuting quantities. A definition of a curved manifold including such variables is given, and a coordinate free formalism reviewed using the super space-time extended version of modern differential geometric techniques. Such a formalism allows the incorporation of internal symmetries in a geometric fashion. Finally we analyse the extended version of Einstein's source-free equation on this manifold, particularly in the linear approximation.     

Proca fields interpretation of spin 1 equation in Robertson-Walker space-time

The general scheme for massive spin 1 equation in curved space-time is specialized to describe the Proca fields. The expressions of the Proca tensor fields are detailed in the Robertson-Walker space-time by means of the solutions of the spin 1 equation in a given tetrad and by the components of the tetrad itself. Asymptotic behaviours of the fields are discussed in the flat, closed and open space-time cases.Also GNFM, Italy     

Normal Modes for Massive Spin 1 Equation in Robertson–Walker Space-Time

The general scheme of the massive spin-1 equation in curved space-time with associated conserved current is considered. A properly covariant scalar product between solutions of the spin-1 equation is defined in a standard way by means of the conservation of the current. The scheme is specialized to the Robertson–Walker space-time where solutions of the spin-1 equation have been previously determined. There results, in case of flat Robertson–Walker space-time, the automatic ortho-normalization property of the solutions, that therefore represent a set of normal modes.     

Wave function of a free electron in a laser plasma via Riemannian geometry

The wave function of a free electron in a laser plasma described via Riemannian geometry is derived by solving the Dirac equation in the associated curved space-time. If the laser field vanishes, the wave function naturally reduces to the case in flat space-time.     

Curved graphene nanoribbons and tunneling current

The density of states and the electronic spectrum of long-wave electrons in a curved graphene nanoribbon is calculated on the basis of the Dirac equation in curved space-time. Using this density of states, we obtain the current-voltage characteristics of tunnel junctions of nanoribbons with metal and quantum dots. The dependence of the curved nanoribbon on the geometric parameters is found.     

Geometric fermions

We study the Kähler-Dirac equation which linearizes the laplacian on the space of antisymmetric tensor fields. In flat space-time it is equivalent to the Dirac equation with internal symmetry and on the lattice it reproduces Susskind fermions. The KD equation in curved space-time differs from the Dirac equation by coupling the gravitational field to the internal symmetry generators. This new way of treating fermionic degrees of freedom may lead to a solution of the generation puzzle but is in conflict with the equivalence principle and with Lorentz invariance on the Planck-mass scale.     

Electromagnetic interpretation of the massless spin-1 field equation in curved space-time

The source-free Maxwell equations associated to the massless spin-1 free field equation are considered in curved space-time. The gauge invariance of the theory is discussed by using as starting point the notion of the spinor potential. The structure of the electromagnetic field in the case of the Robertson-Walker space-time is discussed by using the solutions of the massless spin-1 equations previously determined. The flat-universe case of the standard cosmology is studied exactly and considered in some limiting physical situations.     

Equivalent Forms of Dirac Equations in Curved Space-times and Generalized de Broglie Relations

One may ask whether the relations between energy and frequency and between momentum and wave vector, introduced for matter waves by de Broglie, are rigorously valid in the presence of gravity. In this paper, we show this to be true for Dirac equations in a background of gravitational and electromagnetic fields. We first transform any Dirac equation into an equivalent canonical form, sometimes used in particular cases to solve Dirac equations in a curved space-time. This canonical form is needed to apply Whitham’s Lagrangian method. The latter method, unlike the Wentzel–Kramers–Brillouin method, places no restriction on the magnitude of Planck’s constant to obtain wave packets and furthermore preserves the symmetries of the Dirac Lagrangian. We show by using canonical Dirac fields in a curved space-time that the probability current has a Gordon decomposition into a convection current and a spin current and that the spin current vanishes in the Whitham approximation, which explains the negligible effect of spin on wave packet solutions, independent of the size of Planck’s constant. We further discuss the classical-quantum correspondence in a curved space-time based on both Lagrangian and Hamiltonian formulations of the Whitham equations. We show that the generalized de Broglie relations in a curved space-time are a direct consequence of Whitham’s Lagrangian method and not just a physical hypothesis as introduced by Einstein and de Broglie and by many quantum mechanics textbooks.