标题： tachyon场与流体耦合的改进动力学和引力坍缩 显示英文标题

标题： Improved dynamics and gravitational collapse of tachyon field coupled with a barotropic fluid

摘要： 我们考虑一个具有反平方势的快子场与流体耦合的球对称引力塌缩。 通过引入来自圈量子宇宙学的全纯性修正，我们在半经典描述中分析了塌缩的动力学。 使用动力系统方法，我们发现标准广义相对论设定给出的稳定固定点在当前情况下变为鞍点。 这提供了一种新的动力学，与经典模型中出现的黑洞和裸奇点解形成对比。 我们的结果表明，经典奇点可以通过量子引力效应避免，并被反弹所取代。 通过深入的数值研究，我们表明，根据流体参数$\gamma$，存在一类对应于流体或快子主导区域的解。 此外，对于情况$\gamma \sim 1$，我们发现快子和流体之间存在一种有趣的跟踪行为，导致类似尘埃的塌缩。 此外，我们表明，存在一个临界尺度，该尺度决定了当非奇点黑洞形成时，在相应的塌缩最终阶段何时会出现向外的能量通量。 显示英文摘要

摘要： We consider a spherically symmetric gravitational collapse of a tachyon field with an inverse square potential, which is coupled with a barotropic fluid. By employing an holonomy correction imported from loop quantum cosmology, we analyse the dynamics of the collapse within a semiclassical description. Using a dynamical system approach, we find that the stable fixed points given by the standard general relativistic setting turn into saddle points in the present context. This provides a new dynamics in contrast to the black hole and naked singularities solutions appearing in the classical model. Our results suggest that classical singularities can be avoided by quantum gravity effects and are replaced by a bounce. By a thorough numerical studies we show that, depending on the barotropic parameter $\gamma$, there exists a class of solutions corresponding to either a fluid or a tachyon dominated regimes. Furthermore, for the case $\gamma \sim 1$, we find an interesting tracking behaviour between the tachyon and the fluid leading to a dust-like collapse. In addition, we show that, there exists a threshold scale which determines when an outward energy flux emerges, as a non-singular black hole is forming, at the corresponding collapse final stages.