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arXiv 1302.1644gr-qcastro-ph.HEhep-th
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闭弦快子与修正Chaobergin气体的相互作用及其稳定性

Interacting closed string tachyon with modified Chaplygin gas and its stability

Ali R. Amani, Celia Escamilla-Rivera, H. R. Faghani

摘要:

本文考虑了具有常激子场的闭弦快子模型,并将其与Chaubergin气体相互作用,计算了宇宙学参数。我们在$26$维上研究了该模型,它的$22$维与内部非平坦空间上的紧化有关,它的其它$4$维与FLRW度量有关.取内曲率为负常数,得到了闭弦快子势的四次方程。快子场和标度因子已经实现了作为时间演化和弯曲空间的几何形状的函数,其中标度因子的行为描述了宇宙的加速膨胀。接下来,我们通过引入声速因子来讨论我们模型的稳定性,在我们的情况下,声速因子必须是正函数。通过绘制声速随时间的演化曲线,研究了非平坦宇宙在早期、晚期和未来三个阶段的稳定性条件。结果,我们将看到,在这些情况下,在早期仍然是不稳定的,在晚期仍然是稳定点。

英文摘要:

In this paper, we have considered closed string tachyon model with a constant dilaton field and interacted it with Chaplygin gas for evaluating cosmology parameters. The model has been studied in $26$-dimensional that its $22$-dimensional is related to compactification on an internal non-flat space and its other $4$-dimensions is related to FLRW metric. By taking the internal curvature as a negative constant, we obtained the closed string tachyon potential as a quartic equation. The tachyon field and the scale factor have been achieved as functional of time evolution and geometry of curved space where the behaviour of the scale factor describes an accelerated expansion of the universe. Next, we discussed the stability of our model by introducing a sound speed factor, which one must be, in our case, a positive function. By drawing sound speed against time evolution we investigated stability conditions for non-flat universe in its three stages: early, late and future time. As a result we shall see that in these cases remains an instability at early time and a stability point at late time.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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