论文标题
牛顿动力学获得的扩展宇宙中星系的稳定性
The stability of galaxies in an expanding universe obtained by Newtonian dynamics
论文作者
论文摘要
在Einstein-De保姆宇宙中，通常确定了扩展宇宙中星系的动力学，或者通过修改牛顿动力学（MOND）中的重力长距离景点而进行。在这里，星系的时间演变是由经典分子动态模拟对具有纯重力力的系统的模拟来确定的。延伸以包含空间的哈勃膨胀，将一种用于重新组装重力组装的时间可逆算法，用于重新组装重力系统。该算法在数十亿个时间步长的情况下稳定，没有任何调整。该算法用于模拟银河系的简单模型，并使用宇宙的哈勃膨胀，并在对应于25 GYR的时间的时间进行模拟。旋转的星系会不时失去绑定的对象，但在模拟的末尾仍然稳定。模拟表明，对星系动力学的解释可能是宇宙在宇宙学时代很年轻。尽管银河系的模型在13-14 GYR上相当稳定，这与宇宙的宇宙学时间相对应，但哈勃膨胀将迟早释放出星系中的物体。但是模拟表明，这将首先发生在遥远的未来。
The dynamics of galaxies in an expanding universe is often determined for gravitational and dark matter in an Einstein-de Sitter universe, or alternatively by modifying the gravitational long-range attractions in the Newtonian dynamics (MOND). Here the time evolution of galaxies is determined by simulations of systems with pure gravitational forces by classical Molecular Dynamic simulations. A time reversible algorithm for formation and aging of gravitational systems by self-assembly of baryonic objects, recently derived (Eur. Phys. J. Plus 2022, 137:99), is extended to include the Hubble expansion of the space. The algorithm is stable for billions of time steps without any adjustments. The algorithm is used to simulate simple models of the Milky Way with the Hubble expansion of the universe, and the galaxies are simulated for times which corresponds to more than 25 Gyr. The rotating galaxies lose bound objects from time to time, but they are still stable at the end of the simulations. The simulations indicate that the explanation for the dynamics of galaxies may be that the universe is very young in cosmological times. Although the models of the Milky Way are rather stable at 13-14 Gyr, which corresponds to the cosmological time of the universe, the Hubble expansion will sooner or later release the objects in the galaxies. But the simulations indicate that this will first happen in a far away future.
