String cosmological model in the presence of a magnetic flux
Bijan Saha, Mihai Visinescu
研究了具有磁通量的Bianchi I型弦宇宙学模型。介绍了几个关于宇宙弦和磁流体参数化的合理假设，并给出了一些精确的解析解。
A Bianchi type I string cosmological model in the presence of a magnetic flux is investigated. A few plausible assumptions regarding the parametrization of the cosmic string and magneto-fluid are introduced and some exact analytical solutions are presented.
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Cosmological Solutions of Higher-Curvature String Effective Theories with Dilatons
我们研究了玻色弦和杂化弦以及II型超弦的低能量有效作用量中的高曲率项对理论宇宙学解的影响，直到曲率的四次修正。我们发现，宇宙学的解决方案存在于所有的字符串类型，但他们总是消失时，介子场包括在内，一个结论，可以避免，如果考虑到弦环效应。
Local cosmic strings in Brans-Dicke theory with a cosmological constant
Vilenkin的静态宇宙直弦唯象状态方程与Brans-Dicke理论不一致。我们将证明，在存在一个宇宙学常数的情况下，这个状态方程与Brans-Dicke理论是一致的。给出了描述具有宇宙学常数的宇宙弦内部的全非线性场方程的一般解。
Singularity-free cosmological solutions in string theories
如果时空维数大于10，并且考虑膜的构型，那么在树的水平上可以从弦作用量得到无奇性的宇宙学解。在这种情况下，介子场的行为也是有规律的。渐近辐射阶段达到指示平滑过渡到标准宇宙学模型。
A Class of Stationary Rotating String Cosmological Models
我们得到了一类单参数的定常旋转弦宇宙学模型，其中著名的G $\ddot o $ del Universe是一个特例.通过适当地选择自由参数函数，总是可以满足能量条件。模型的旋转取决于宇宙学常数，而这个常数是负的。
The present study deals with LRS Bianchi type I cosmological model representing massive string. The energy-momentum tensor for such string as formulated by Letelier (1983) is used to construct massive string cosmological models for which we assume that the shear scalar ($σ$) is proportional to the expansion scalar ($θ$). The study reveals that massive strings dominate the early Universe. The strings eventually disappear from the Universe for sufficiently large time, which is in agreement with the current astronomical observations. Some physical and geometrical behaviour of models are also disc…
Magnetized String Cosmological Model in Cylindrically Symmetric Inhomogeneous Universe with Variable Cosmological-Term $Λ$
研究了宇宙项$Λ$随时间变化的非均匀磁化弦宇宙学模型.为了获得确定性解，假设模型中的展开（$θ$）与剪切张量$σ^{i}_{j}$的本征值$σ^{1}_{1}$成比例。该模型的宇宙学常数值较小且为正值，这一结果得到了最近Ia超新星观测结果的支持。讨论了该模型在有无磁场作用下的物理和几何性质。
Cosmological constant influence on cosmic string spacetime
我们研究了在存在宇宙学常数的情况下，线性宇宙弦周围时空的线元。我们得到的度量，并认为它应该被丢弃，因为渐近的考虑。然后得到了该度量的一个依赖于时间的相容形式，并讨论了它的性质。
Homogeneous magnetic fields in fully anisotropic string cosmological backgrounds
本文给出了具有纯磁分量的均匀麦克斯韦场弦宇宙学有效作用量的新解。在空间独立的双光子和挠率背景为零的情况下，得到了精确解。在我们的例子中，四维度量是Bianchi III型和VI型$_{-1}$或Kantowski-Sachs。
A Bianchi type-I cosmological model in the presence of a magnetic flux along a cosmological string is considered. The first objective of this study is to investigate Einstein equations using a tractable assumption usually accepted in the literature. Quantum effects of the present cosmological model are examined in the framework of loop quantum cosmology. Finally we draw a parallel between the classical and quantum approaches.
The loop quantum cosmology of the Bianchi type II string cosmological model in the presence of a homogeneous magnetic field is studied. We present the effective equations which provide modifications to the classical equations of motion due to quantum effects. The numerical simulations confirm that the big bang singularity is resolved by quantum gravity effects.
We present a review of black holes and black string solutions available in the $d$-dimensional Einstein and Einstein-Maxwell model in the presence of a cosmological constant. Due to the cosmological constant, the equations do not admit explicit solutions for generic values of the parameters and numerical methods are necessary to construct the solutions. Several new features of the solutions are discussed, namely their stability and the occurrence of non-uniform black strings which depend non-trivially on the co-dimension. Black string solutions are further constructed for the Einstein-Gauss-Bo…
Bianchi type-I string cosmological model in the presence of a magnetic flux: exact and qualitative solutions
研究了在宇宙弦上存在磁通量的Bianchi I型宇宙模型。本研究的目的是使用文献中通常接受的一些易处理的假设来生成爱因斯坦方程的解。解析解的补充与数值和定性分析。在本模型的框架下，讨论了宇宙的演化和其他物理方面。
A New Class of String Cosmological Models in Cylindrically Symmetric Inhomogeneous Universe
研究了一类新的柱对称非均匀弦宇宙模型。为了得到确定性解，假设模型中的展开（$θ$）与剪切张量$σ^{i}_{j}$的本征值$σ^{1}_{1}$成比例。模型的物理和几何方面进行了讨论。
We report the effect of the cosmological constant and the internal energy density of a cosmic string on the deflection angle of light in the spacetime of a rotating cosmic string with internal structure. We first revisit the deflection angle by a rotating cosmic string and then provide a generalization using the geodesic equations and the Gauss-Bonnet Theorem. We show there is an agreement between the two methods when employing higher order terms of the linear mass density of the cosmic string. By modifying the integration domain for the global conical topology, we resolve the inconsistency be…
In this paper we have studied Kaluza-Klein string cosmological model within the framework of f(R; T) theory of gravity, where R is the Ricci scalar and T is the trace of the stress energy momentum tensor. We have obtained the solution of the corresponding field equations by using a time varying deceleration parameter. We also discussed various physical and dynamical properties of the model. The variation of different cosmological parameters are shown graphically for specific values of the parameters of the model.
Bianchi type V string cosmological models in general relativity are investigated. To get the exact solution of Einstein's field equations, we have taken some scale transformations followed by Camci $\it et ~ al$ (2001). It is shown that Einstein's field equations are solvable for any arbitrary cosmic scale function. Solution for particular form of cosmic scale functions are also obtained. Some physical and geometrical aspects of the models are discussed.
Bianchi Type III String Cosmological Models with Time Dependent Bulk Viscosity
研究了具有体粘滞流体的Bianchi III型弦宇宙学模型。为了得到宇宙的确定性模型，我们假定模型中的体粘滞系数（$ξ$）与膨胀系数（$θ$）成反比，膨胀系数（$θ$）与剪切系数（$σ$）成正比。这导致$B = \ell C^{n}$、$\ell$和$n$是常数。在存在和不存在体积粘度的模型的行为进行了讨论。模型的物理意义也进行了详细讨论。
In this paper, we find exact string cosmological solutions for FRW cosmology, by using Hojman symmetry approach. The string cosmology under consideration includes a scalar field $ψ(t)$ with the potential $W(ψ)$, and a totally antisymmetric field strength $H_{μνρ}$ which is specifically defined in terms of the scale factor $a(t)$. We show that for this string cosmology, Hojman conserved quantities exist using which new exact solutions for the scale factor and the scalar field are obtained for specific potentials $W(ψ)$ with some free parameters. The presence of these parameters, together with t…
In the present letter, we consider the DeBroglie-Bohm interpretation of quantum Friedmann-Robertson-Walker models in the presence of a negative cosmological constant and cosmic strings. We compute the Bohm's trajectories and quantum potentials for a quantity related to the scale factor. Then, we compare our results with the ones already in the literature, where the many worlds interpretation of the same models was used.
Instability of cosmological event horizons of non-static global cosmic strings
研究了Gregory [Phys.Rev.D54，4955（1996）]最近发现的一类非静态整体宇宙弦的宇宙学事件视界的稳定性。结果表明，它们是不稳定的测试粒子和物理扰动。特别是，零尘流体扰动的反作用将使它们变成时空奇点。当这些奇异超曲面接近时，测试粒子的畸变在几何上发散，由此产生的奇异性是强的。
Here, we have investigated the interaction of Bianchi type I anisotropic cloud string cosmological model universe with electromagnetic field in the context of general relativity. In this paper, the energy momentum tensor is assumed to be the sum of the rest energy density and string tension density with an electromagnetic field. To obtain exact solutions of Einstein field equations, we take average scale factor as an integrating function of time. Also, the dynamics and significance of various physical parameters of model are discussed.
Charged Hayward black hole with a cosmological constant and surrounded by quintessence and a cloud of strings
本文获得了一族扩展Hayward黑洞的精确解，描述了带宇宙常数、浸没于暗能量并伴有弦云的带电Hayward黑洞场景，并分析了Kretschmann标量随参数的变化及测地线与有效势。
Bianchi type V string cosmological models with bulk viscosity for massive string are investigated. The bulk viscosity is assumed to vary with time in such a manner that it is related to simple power function of the energy density. Using generation technique (Camci~et~al., 2001), it is shown that Einstein's field equations are solvable for any arbitrary cosmic scale function. Solution for particular form of cosmic scale functions are also obtained. It is found that solutions based on generation technique are relevant to the observational results. Some physical and geometrical aspect of the mode…
Some Bianchi Type III String Cosmological Models with Bulk Viscosity
我们研究了宇宙弦在Bianchi III时空中的可积性，在存在一个大的粘性流体通过应用一种新的技术。该模型的行为减少到一个单一的二阶非线性微分方程的解决方案。我们表明，这个方程承认一个无限的家庭的解决方案。一些物理后果，从这些结果进行了讨论。
Bianchi Type I Massive String Magnetized Barotropic Perfect Fluid Cosmological Model in General Relativity
利用Latelier和Stachel的方法研究了具有正压理想流体分布的磁场的Bianchi I型质量弦宇宙学模型。为了得到宇宙的确定性模型，假设宇宙中充满正压理想流体分布。磁场是由于沿x轴产生的具有无限电导率的电流。在存在和不存在磁场与其他物理方面的模型的行为进行了进一步讨论。
Charged-rotating black holes and black strings in higher dimensional Einstein-Maxwell theory with a positive cosmological constant
我们提出的论点，在$d=2N+1$维度的充电，旋转黑洞的存在，与$d\geq 5$与一个积极的宇宙学常数。这些解同时包含一个规则视界和一个球形拓扑的宇宙视界，并且具有$N$等大小的角动量。它们渐近地接近德西特时空背景。通过假设场与额外维$y$无关，研究了$d=2N+2$的对应方程，得到了黑弦解.这些解在事件视界是正则的。度量的渐近形式不是de Sitter形式，并且在有限真距离处表现出裸奇异性。
Non-abelian black strings and cosmological constant
研究了具有宇宙学常数$Λ$的五维Einstein-Yang-Mills模型的经典解.使用球对称假设并假设场不依赖于额外维度，我们将方程转换为一组微分方程，并进行数值求解。我们构造了新的正则类型（分别为）。黑洞）的解决方案，接近原点（分别。事件视界）类似于4维引力单极（分别为非阿贝尔黑洞），并研究它们的整体性质。
Cosmological String Backgrounds
1992年9月2日至20日在科孚岛“第四希腊基本粒子物理学学校”发表的演讲：回顾了宇宙时空背景中弦的传播。本文给出了一类特殊的宇宙学背景与精确共形场论的关系。特别强调的是宇宙时空的奇异性结构和弦背景的离散对偶对称性。
Cylindrically symmetric, static strings with a cosmological constant in Brans-Dicke theory
在Brans-Dicke理论框架下研究了具有宇宙学常数的静态柱对称真空解.其中一些承认洛伦兹增强沿对称轴不变性的解对应于具有宇宙学常数的局部、直宇宙弦。研究了这类溶液的一些物理性质。这些线对测试颗粒施加吸引力或排斥力。一个光滑的匹配也进行了最近推出的内部粗弦解决方案与宇宙学常数。
Cosmological String Solutions in 4 Dimensions from 5d Black Holes
通过把一个五维黑洞和黑洞--deSitter Einstein引力解降为四维，得到了低能有效弦论的宇宙学四维解.在四维有效弦作用量中，由于在五维Einstein-Hilbert作用量中出现了一个宇宙学常数，从而产生了一个特殊的介子势。我们的解决方案实施的宇宙学方案进行了讨论。
We have discussed a particular class of exact cosmological solutions of the 4-dimensional low energy string gravity in the string frame. In the vacuum without matter and the 2-form fields, the exact cosmological solutions always give monotonically shrinking universes if the dilaton field is not a constant. However, in the presence of the 2-form fields and/or the radiation-like fluid in the string frame, the exact cosmological solutions show a minimum size of the universe in the evolution, but with an initial cosmological curvature singularity in the string frame.
Effect of a positive cosmological constant on cosmic strings
我们研究了宇宙学常数为正的时空中的宇宙Nielsen-Olesen弦。对于圆柱对称时空中的自由宇宙弦，我们计算了宇宙学常数对角亏损和零测地线弯曲的贡献。对于Schwarzschild-de Sitter时空中的宇宙弦，我们使用围绕内视界和外视界的Kruskal补丁来证明细线可以穿透它们。
We present exact solutions of string cosmological models characterized by five dimensional metrics (with four-dimensional real Lie groups as isometry groups), space independent dilaton and vanishing torsion. As an example we consider VII 0 \oplus R model and show that it is equivalent to the (4 +1)-dimensional cosmological model coupled to perfect fluid with negative deceleration parameters (accelerating universe).
We propose a mechanism to have a smooth transition from a pre-Big Bang phase to a standard cosmological phase. Such transition is driven by gravitational production of heavy massive string states that backreact on the geometry to stop the growth of the curvature. Close to the string scale, particle creation can become effective because the string phase space compensate the exponential suppression of the particle production. Numerical solutions for the evolution of the Universe with this source are presented.
Exact solutions of the Einstein field equations with cosmic string and space varying cosmological constant, viz., $Λ= Λ(r)$, in the energy-momentum tensors are presented. Three cases have been studied: where variable cosmological constant (1) has power law dependence, (2) is proportional to the string fluid density, and (3) is purely a constant. Some cases of interesting physical consequences have been found out such that (i) variable cosmological constant can be represented by a power law of the type $Λ=3r^{-2}$, (ii) variable cosmological constant and cosmic string density are interdependent…
Cosmological Spinning Multi-`Black-Hole' Solution in String Theory
本文给出了具有正宇宙学常数的Einstein-Maxwell-Dilaton-Axion理论中的宇宙学自旋多黑洞解。这个解决方案是宇宙学的量子Israel-Wilson-Perjes解决方案，并描述了几个旋转的“黑洞”的碰撞。
Wilsonian renormalization group properties of a novel non-critical cosmological string configuration
我们证明了在[1]中发现的一个精确的非临界弦宇宙学位形，它是一个精确的Wilson重整化群方程的红外稳定不动点.
Quantum Corrections for a Cosmological String Solution
我们研究弦有效作用量的宇宙学解的量子修正。出发点是一个包含一个反对称张量场、一个介子和一个在标量场中具有奇点的模场的经典解。作为第一步，我们在奇点附近对标量场进行微扰，结果是奇点消失，一般情况下，非微扰量子修正在标量场中形成一个势。
Cosmological and Wormhole Solutions in Low-Energy Effective String Theory
导出并研究了低能有效弦场论的一类宇宙学解和虫洞解。我们考虑一般的四维弦有效作用量，其中紧化流形的模和电磁场存在。本文讨论了二维有效理论的宇宙学解。特别地，我们证明了二维理论具有标度因子对偶不变性。发现了描述婴儿宇宙成核的欧几里得四维瞬子，并给出了成核过程的概率幅。
On certain cosmological relics of the early string dynamics
对早期弦动力学的宇宙学遗迹的追踪可能会增强该理论，并为主要的宇宙学问题提供新的视角。这一点在首阶Bianchi型$VII_0$弦背景中示出，其中空间各向同性可以被称为这样的遗迹。一个精细得多的粒子，来自一个前引力波，可以从它在宇宙微波背景的小尺度结构上的印记中检索出来。尽管不存在传统的暴胀，但由于存在同样基本的混合动力学，因此不存在视界问题。因此，更一般的宇宙学混合问题的影响和某些新的观点进行了简要的讨论。
The Wheeler-De Witt equation of type IIB quantum string cosmology compactified with constant internal H-fluxes on a 6-torus, whose volume modulus is frozen, is solved under the WKB approximation. The spontaneous symmetry breaking of the S-duality group by H-fluxes is also examined.
A Positive Cosmological Constant in String Theory Through Ads/CFT Wormholes
有两个重要的物理系统违反了强能量条件：宇宙（就像我们自己的宇宙一样）具有正的宇宙学常数，以及虫洞。我们认为，一个积极的宇宙学常数可以调和与弦论考虑虫洞弦背景。这是认为在两个方向：首先，我们表明，膜世界与积极的宇宙学常数引起的散装奇性，最好的解决嵌入膜世界中的AdS/CFT虫洞;第二，对于最简单的一种虫洞在渐近AdS空间，我们表明，IR稳定的物质需要保持虫洞开放需要存在的膜世界。这样，紫外稳定性条件就禁止膜世界出现负的宇宙学常数。
Null string evolution in black hole and cosmological spacetimes
讨论了经典弦在某些黑洞和宇宙时空中的运动问题。特别地，考虑了张力弦的零弦极限（零张力）。本文给出了Reissner-Nordström黑洞背景下、Einstein静态宇宙和Einstein-Schwarzschild（Einstein静态宇宙中的一个黑洞）时空中的一些新的精确弦解.这些解决方案可以提供一些洞察弦（宇宙和基本）在弯曲背景中传播的一般性质。
Cosmological Constant in Low Energy $d = 4$ String Leads to Naked Singularity
在西格玛模型方法中，非临界弦的$β$函数方程包含一个类似树级宇宙学常数的项，$Λ$ .我们分析了这些方程在$d = 4$时空中的静态球对称解，并证明了弦的曲率标量是奇异的，如果$Λ\ne 0$。这个奇点是赤裸的。要求它在我们的宇宙中不存在，就在自然单位中施加了$| Λ| < 10^{- 120}$约束。{}从另一个角度来看，我们的分析意味着低能$d = 4$非临界弦导致裸奇点。
It has been claimed that the cosmological constant in AdS black holes such as the BTZ black hole plays the role of the thermodynamic variable of a pressure in the thermodynamic first law and the Smarr relation from the scaling law of the Christodoulou-Ruffini formula. However, the dual solution of the BTZ black hole is the black string which is asymptotically flat despite the presence of the cosmological constant, and so the explicit form of the pressure with the role of the cosmological constant is unclear in the black string since the pressure is subject to the choice of the energy-momentum …
Dynamics in Nonlocal Cosmological Models Derived from String Field Theory
本文讨论一类非定域宇宙模型。提出了一种求解非局部Friedmann方程的新方法，并给出了具有非局部算子的Friedmann方程的解。这些解决方案的宇宙学性质进行了讨论。特别是$p$ -adic宇宙学模型，我们在其中得到了非奇异的弹跳解;弦场论快子模型，我们在其中用$w=-1$得到了非定域Friedmann方程的大时间完全解。本文还讨论了从非定域宇宙学模型中获得实际宇宙学常数值的可能性。
We investigate string or branelike solutions for four-dimensional vacuum Einstein equations in the presence of cosmological constant. For the case of negative cosmological constant, the Banados-Teitelboim-Zanelli black string is the only warped stringlike solution. The general solutions for nonwarped branelike configurations are found and they are characterized by the Arnowitt-Deser-Misner mass density and two tensions. Interestingly, the sum of these tensions is equal to the minus of the mass density. Other than the well-known black string and soliton spacetimes, all the static solutions poss…
In this paper, we investigate the fermionic current densities induced by a magnetic flux running along the idealized cosmic string in a four-dimensional spacetime, admitting that the coordinate along the string's axis is compactified. In order to develop this investigation we construct the complete set of fermionic mode functions obeying a general quasiperiodicity condition along the compactified dimension. The vacuum expectation value of the azimuthal current density is decomposed into two parts. The first one corresponds to the uncompactified cosmic string geometry and the second one is the …
Vacuum Polarization by a Magnetic Flux in a Cosmic String Background
本文分析了宇宙弦背景中磁通量对无质量费米子场的真空极化效应。考虑了三种不同的磁场结构。在所有这些方法中，磁通量都被限制在有限半径的长圆柱管中。
The Rise and Fall of the Cosmic String Theory for Cosmological Perturbations
宇宙学波动的宇宙弦论是宇宙学健康科学进展的一个很好的例子。这是一个定义明确的物理模型，已经被宇宙学观测所检验，并被排除为原始波动的主要来源。直到大约15年前，关于宇宙学扰动的宇宙弦论，还是产生原始扰动的两个物理学候选理论之一。在过去十年中出现的宇宙学数据已经与理论的明确预测进行了比较，并排除了宇宙弦作为原始宇宙学扰动的主要来源。由于宇宙弦在包括超对称和基本弦论在内的许多微观物理理论中都被预言在暴胀后形成，它们的观测边界可能成为这些理论的严重限制。这是一个教学回顾的历史发展，宇宙弦论的主要预测和宇宙学观测强加给它的限制。最近的透镜事件，可以归因于较轻的宇宙弦进行了讨论。
The present study deals with locally rotationally symmetric (LRS) Bianchi type II cosmological models representing massive string. The energy-momentum tensor for such string as formulated by Letelier (1983) is used to construct massive string cosmological models for which we assume that the expansion ($θ$) in the models is proportional to the shear ($σ$). This condition leads to $A = B^{m}$, where A and B are the metric coefficients and m is constant. We have derived two types of models depending on different values of m i.e. for $m\neq \sqrt{2}$ and $m = \sqrt{2}$ respectively. For suitable c…
Cosmological Solutions in String Theories
我们在$D$维的弦论中得到了一大类在环形紧化低能极限下的宇宙学解。我们考虑的解决方案，其中一个$p$维子集的空间坐标，参数化一个平坦的空间，一个球体，或一个双曲面，描述的空间部分的物理观察到的宇宙。运动方程化为Liouville或$SL(N+1,R)$ Toda方程，它们是精确可解的。我们详细研究了其中的一些情况，发现在适当的条件下，它们可以描述四维膨胀宇宙。我们还讨论了如何在$D$维度的解决方案氧化回$D=10$弦论或$D=11$ M-理论的行为。
It was proved more than three decades ago, that the first order $α'$ correction of string effective theory could be written as the Gauss-Bonnet term, which is the quadratic term of Lovelock gravity. In cosmological background, with an appropriate field redefinition, we reorganize the infinite $α'$ corrections of string effective action into a finite term expression for any specific dimension. This finite term expression matches Lovelock gravity exactly and thus fix the couplings of Lovelock gravity by the coefficients of string effective action. This result thus provides a strong support to st…
Strings and Multi-Strings in Black Hole and Cosmological Spacetimes
本文介绍了在各种不同维度的黑洞和宇宙时空中经典弦和量子弦的最新结果。所考虑的弯曲背景包括$2+1$黑洞反德西特时空及其对偶、黑弦、具有或不具有宇宙学常数的普通$D\geq 4$黑洞、德西特和反德西特时空以及静态罗伯逊-沃克时空。在这些背景下得到弦的运动方程和约束的精确解，并描述了它们的物理性质（长度、能量、压力）。{ \it multi-string}解的存在性，描述了无穷多个弦，被证明是具有正或负宇宙学常数的时空的一般特征。此外，使用正则量子化程序，我们发现弦的质量谱在德西特和反德西特时空。与平坦闵可夫斯基时空中的弦谱相比，新的特征出现了，例如在德西特和反德西特时空中引力子以外的所有能级上的{ \it精细结构效应}，以及在反德西特时空中哈格多恩温度的{ \it不存在}。最后，我们考虑了空间曲率对Robertson-Walker时空中弦动力学的影响。
The Nature of Singularity in Bianchi I Cosmological String Gravity Model with Second Order Curvature Corrections
本文研究了通过Gauss-Bonnet项与引力耦合的量子M场理论中的Bianchi I宇宙模型。区分了两类M宇宙奇点。前者类似于M的爱因斯坦引力奇点，后者（在M经典广义相对论中没有出现）发生在M场方程组的主行列式为零时。本文讨论了后M宇宙学奇点与M是一根电子头发的黑洞内部奇点的类比。通过对运动方程的数值积分，找到了导致这两种宇宙学奇点的初始条件。
In this paper we show how the string landscape can be constrained using observational data. We illustrate this idea by focusing on Fibre Inflation which is a promising class of string inflationary models in type IIB flux compactifications. We determine the values of the microscopic flux-dependent parameters which yield the best fit to the most recent cosmological datasets.
Flux-Confinement in Dilatonic Cosmic Strings
我们研究了平坦时空中的介子电动力学，并给出了一组整体宇宙弦解，其中磁通量是受限的。这些解决方案继续存在一个足够小的量子质量，但停止这样做取决于磁通量的临界值以上。也存在畴壁和Dirac介子解。我们讨论了一种机制，即磁粒子可能已被限制在一个时代，在早期宇宙中，在此期间的介子是无质量的介子宇宙弦。
Global phase time and path integral for string cosmological models
从闭合玻色弦论的低能有效作用量出发，确定了均匀和各向同性宇宙学模型的全局相时。当哈密顿约束允许存在内禀时间时，量子跃迁振幅可通过规范系统通常的路径积分方法得到。
Black strings with negative cosmological constant: inclusion of electric charge and rotation
通过引入电磁场，我们推广了最近文献中讨论的具有负宇宙学常数的真空静态黑弦。这些更高维的构型不依赖于“紧致”额外维度，它们的边界拓扑是时间和$S^{d-3}\times S^1$或$H^{d-3}\times S^1$的乘积。旋转推广的偶数维黑弦配置被认为是。与静态中性情况不同，对于消失的事件视界半径，没有发现有规律的极限。我们探讨数值的一般性质，这样的解决方案，并使用一个counterterterm处方，我们计算其保守的费用，并讨论其热力学。我们发现，在AdS背景下，黑弦的热力学性质遵循相应的黑洞解的模式。
Strings from Flux Tube Solutions in Kaluza-Klein Theory
我们在Kaluza-Klein理论的框架下计算了引力通量管解的降维。第五维被简化为普朗克大小的区域。假设管的宽度也是普朗克尺寸，我们得到弦状物体，其物理场起源于初始5D度量。这些领域的动态是内在的。
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