We present a discontinuous Galerkin-finite difference hybrid scheme that allows high-order shock capturing with the discontinuous Galerkin method for general relativistic magnetohydrodynamics in dynamical spacetimes. We present several optimizations and stability improvements to our algorithm that allow the hybrid method to successfully simulate single, rotating, and binary neutron stars. The hybrid method achieves the efficiency of discontinuous Galerkin methods throughout almost the entire spacetime during the inspiral phase, while being able to robustly capture shocks and resolve the stellar surfaces. We also use Cauchy-characteristic evolution to compute the first gravitational waveforms at future null infinity from binary neutron star mergers. The simulations presented here are the first successful binary neutron star inspiral and merger simulations using discontinuous Galerkin methods.

中文翻译：

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使用间断 Galerkin-finite difference 混合方法的双中子星合并


我们提出了一种间断的 Galerkin-finite difference hybrid scheme，该方案允许使用间断 Galerkin 方法对动力学时空中的广义相对论磁流体动力学进行高阶冲击捕获。我们提出了对算法的几项优化和稳定性改进，使混合方法能够成功模拟单中子星、旋转中子星和双中子星。在螺旋阶段，混合方法几乎在整个时空中实现了间断伽辽金方法的效率，同时能够稳健地捕捉激波并分辨恒星表面。我们还使用柯西特征演化来计算双中子星合并在未来零无穷大处的第一个引力波形。这里介绍的模拟是第一个使用间断 Galerkin 方法成功的双中子星螺旋和合并模拟。