Multicomponent relativistic fluids have been studied for decades. However, simulating the dynamics of the particles and fluids in such a mixture has been a challenge due to the fact that such simulations are computationally expensive in three spatial dimensions. Here, we report on the development and application of a multidimensional relativistic Monte Carlo code to explore the thermalization process in a relativistic multicomponent environment in a computationally inexpensive way. As an illustration we simulate the fully relativistic three-dimensional Brownian-motion-like solution to the thermalization of a high-mass particle (proton) in a bath of relativistic low-mass particles (electrons). We follow the thermalization and ultimate equilibrium distribution of the Brownian-like particle as can happen in the cosmic plasma during big-bang nucleosynthesis. We also simulate the thermalization of energetic particles injected into the plasma as can occur, for example, by the decay of massive unstable particles during the big bang.

中文翻译：

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多组分相对论热模拟

多组分相对论流体已经研究了数十年。然而，由于这样的模拟在三个空间维度上计算上昂贵的事实，因此在这种混合物中模拟颗粒和流体的动力学一直是一个挑战。在这里，我们报告多维相对论的蒙特卡洛代码的开发和应用，以相对便宜的方式探索相对论多分量环境中的热化过程。作为说明，我们模拟了相对论的三维布朗运动样解，以解决相对论的低质量粒子（电子）浴中高质量粒子（质子）的热化问题。我们遵循大爆炸核合成过程中宇宙等离子体中可能发生的布朗样粒子的热化和最终平衡分布。我们还模拟了注入等离子体中的高能粒子的热化过程，例如在大爆炸期间大量不稳定颗粒的衰变会发生这种情况。